暖通毕业设计外文翻译---地源热泵系统的模拟与设计

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毕业设计外文文献地源热泵和空气 - 水热泵

毕业设计外文文献地源热泵和空气 - 水热泵
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devices that draw heat from the ground (with horizontal ground heat exchangers) and heat the building are called ground source heat pumps GSHP, Figure 1; devices that draw heat from the external air and heat the building using a water heating system are called air-to-water heat pumps A&WHP, Figure 2. Comparing the efficiency of GSHP and A&WHP in cold climate areas it is necessary to pay attention to the following aspects: A&WHP should be operated at temperatures of ambient air below −20˚C or even down to −30˚C and using additional heat sources (electrical heaters) might be necessary [1]; soil temperatures in the depth of the horizontal ground heat collector decrease to the freezing point (0˚C) in winter and the soil around the collector pipes might be frozen [2]; a rather low floor heating water temperature regime (35/30˚C) should be used in order to achieve the best possible COP value of heat pumps [2].

外文翻译---气候条件对地源热泵系统性能的影响

外文翻译---气候条件对地源热泵系统性能的影响

外文翻译---气候条件对地源热泵系统性能的影响在中国的建筑中,加热和冷却消耗了大量的能源。

为了满足这些需求,锅炉和空调是最常用的设备。

但是,热泵作为一种可以利用建筑周围可再生能源的设备,在许多应用中也得到了广泛使用。

本文将讨论气候条件对地源热泵系统性能的影响。

2.地源热泵系统的工作原理地源热泵系统是一种利用地下土壤或水体中的热能来加热或冷却建筑物的系统。

该系统通过地下水管或地下热交换器将热能传输到建筑物内部。

地源热泵系统的工作原理与空气源热泵系统相似,但地源热泵系统更加稳定,因为土壤温度的波动比空气温度的波动更小。

3.气候条件对地源热泵系统性能的影响气候条件对地源热泵系统的性能有很大的影响。

如果地源热泵系统只从土壤中吸取热量,那么在两个月后,地源热泵附近的土壤温度将会降至20摄氏度以下。

如果向土壤排入相同的热量三个月,土壤温度将会超过37摄氏度,这将不再适合于空调系统。

因此,在设计地源热泵系统时,需要考虑到热量的平衡,以确保土地资源的可持续利用。

4.解决热不平衡的措施在一些热不平衡的工程实例设计中,可以考虑一些措施来解决这个问题。

例如,可以通过增加地下热交换器的长度或者增加热交换器的数量来增加地源热泵系统的热量输出。

此外,还可以采用其他的辅助加热或冷却设备来平衡热量的不足或过剩。

5.结论综上所述,气候条件对地源热泵系统的性能有很大的影响。

为了实现地源热泵系统的可持续利用,需要平衡向土地排入的热量与从土地吸取的热量。

在设计中,需要考虑到热量的平衡,以确保系统的稳定性和可靠性。

能源消费量中,家庭取暖和降温的比例是相等的。

在中国,煤是主要的初级能源,但煤是不可再生的。

地源热泵是一种有效的供暖和降温方式,因为它们利用建筑物周围的可再生热源。

地源热泵系统比空气源热泵系统更具优势,主要表现在几个方面:(a)消耗更少的能量,(b)在极低温度下不需要额外的加热,(c)使用较少的制冷剂,(d)设计简单,维护费用较少,(e)不需要检查风化的部位。

暖通毕业设计外文翻译---地源热泵系统的模拟与设计

暖通毕业设计外文翻译---地源热泵系统的模拟与设计

参考文献<<地源热泵系统的模拟与设计>>摘要:总结了近年来地源热泵系统的模拟和设计方面的研究和进展。

首先给出了地源热泵系统各部件建模方面的进展,包括竖直埋管地热换热器、单井循环系统以及在地源热泵混合系统中采用的几种辅助散热装置。

其次,讨论现场测定深层岩土热物性的技术。

第三,介绍竖直埋管地热换热器的设计方法。

最后,给出在设计地源热泵系统中采用系统模拟的几个应用实例。

关键词:热泵;地热换热器;热物性;混合系统;模型;设计;模拟1.简介从热力学的观点来看,在空调系统中利用地源热作为热源或者冷源是吸引人的。

这是因为,从全年来看,其温度比环境干球或湿球温度更接近于室内(所需要)的温度。

基于这个原因,地源热泵系统较之空气源热泵系统在高效率上更具有潜力。

在实际情况中,源热泵系统由于没有设备暴露在外部的环境中,花在维修方面的费用是比较低的(Cane, et al. 1998).虽然已经有一些地源热泵系统技术在斯堪的那维亚半岛得到发展,但是其商业上的开发利用却是在美国做得最好。

这是主要是因为在美国已经存在着一个很大的住宅空调系统市场。

其系统由于有着较低的能耗和低运行费用已经证明吸引了很多业主。

在美国很多地区用电峰值取决于空调用电量。

对于这个原因使得一些电力设备公司对这个系统很感兴趣,他们希望通过使用这样的系统来减少对电力的需求。

一些小型商业机构和公共部门已经研究出这种技术的应用。

地源热泵系统由于其较低的运行费用而吸引一些学校主管,并有越来越多的学校使用。

在美国关于地源热泵技术实际应用的一些实例研究细节已经交给GHPC。

在论文接下来的部分中我们首先会给出地源热泵系统各部件建模方面的进展,包括竖直埋管地热换热器、水源热泵、单井循环系统以及在地源热泵混合系统中采用的几种辅助散热装置。

由于要设计地下换热器首先就要了解地热的属性,这篇论文的第二部分简要介绍了确定深层岩土热物性的模型,这种方法是由对测试孔温度反应的现场测试法引申而来的。

浅析地暖供热系统设计中英文对照

浅析地暖供热系统设计中英文对照

浅析地暖供热系统设计中英文对照Analysis of floor heating system design in Chinese and English.能源问题和环境问题是我国建设和谐社会的必须要面对的两大难题。

为此我们对建筑节能的技术的研究,不仅可以促进能源资源节约和合理利用,缓解我国能源供应与经济社会发展的矛盾,而且对于加快发展循环经济,实现经济社会的可持续发展,起着举足轻重的作用。

因此,我们越来越多的采用舒适、节能和运行成本较低的地暖供热系统,克服了诸如耗能大、舒适性差、难于分户计算、占用房间使用面积等问题。

一、地暖的特点The problem of energy and environment are two major problems in China's construction of a harmonious society must face. We therefore on building energy conservation technology research, not only can promote energy conservation and reasonable utilization of resources, ease the contradiction between energy supply and the development of economic society in China, but also for accelerating the development of recycling economy, achieve sustainable economic and social development, play a decisive role. Therefore, floor heating system and comfortable, energy-saving and low operation cost by us more and more, such as the energy to overcome the large, poor comfort, difficult to calculate household, occupation of the using area of the room etc.. One, warm (1)舒适度高、卫生保健。

暖通空调专业-毕业设计外文翻译

暖通空调专业-毕业设计外文翻译

Refrigeration System Performance using Liquid-Suction Heat ExchangersS. A. Klein, D. T. Reindl, and K. BroWnellCollege of EngineeringUniversity of Wisconsin - MadisonAbstractHeat transfer devices are provided in many refrigeration systems to exchange energy betWeen the cool gaseous refrigerant leaving the evaporator and Warm liquid refrigerant exiting the condenser. These liquid-suction or suction-line heat exchangers can, in some cases, yield improved system performance While in other cases they degrade system performance. Although previous researchers have investigated performance of liquid-suction heat exchangers, this study can be distinguished from the previous studies in three Ways. First, this paper identifies a neW dimensionless group to correlate performance impacts attributable to liquid-suction heat exchangers. Second, the paper extends previous analyses to include neW refrigerants. Third, the analysis includes the impact of pressure drops through the liquid-suction heat exchanger on system performance. It is shoWn that reliance on simplified analysis techniques can lead to inaccurate conclusions regarding the impact of liquid-suction heat exchangers on refrigeration system performance. From detailed analyses, it can be concluded that liquid-suction heat exchangers that have a minimal pressure loss on the loW pressure side are useful for systems using R507A, R134a, R12, R404A, R290, R407C, R600, and R410A. The liquid-suction heat exchanger is detrimental to system performance in systems using R22, R32, and R717.IntroductionLiquid-suction heat exchangers are commonly installed in refrigeration systems With the intent of ensuring proper system operation and increasing system performance.Specifically, ASHRAE(1998) states that liquid-suction heat exchangers are effective in:1) increasing the system performance2) subcooling liquid refrigerant to prevent flash gas formation at inlets to expansion devices3) fully evaporating any residual liquid that may remain in the liquid-suction prior to reaching the compressor(s)Figure 1 illustrates a simple direct-expansion vapor compression refrigeration system utilizing a liquid-suction heat exchanger. In this configuration, high temperature liquid leaving the heat rejection device (an evaporative condenser in this case) is subcooled prior to being throttled to the evaporator pressure by an expansion device such as a thermostatic expansion valve. The sink for subcoolingthe liquid is loW temperature refrigerant vapor leaving the evaporator. Thus, the liquid-suction heat exchanger is an indirect liquid-to-vapor heat transfer device. The vapor-side of the heat exchanger (betWeen the evaporator outlet and the compressor suction) is often configured to serve as an accumulator thereby further minimizing the risk of liquid refrigerant carrying-over to the compressor suction. In cases Where the evaporator alloWs liquid carry-over, the accumulator portion of the heat exchanger Will trap and, over time, vaporize the liquid carryover by absorbing heat during the process of subcooling high-side liquid.BackgroundStoecker and Walukas (1981) focused on the influence of liquid-suction heat exchangers in both single temperature evaporator and dual temperature evaporator systems utilizing refrigerant mixtures. Their analysis indicated that liquid-suction heat exchangers yielded greater performance improvements When nonazeotropic mixtures Were used compared With systems utilizing single component refrigerants or azeoptropic mixtures. McLinden (1990) used the principle of corresponding states to evaluate the anticipated effects of neW refrigerants. He shoWed that the performance of a system using a liquid-suction heat exchanger increases as the ideal gas specific heat (related to the molecular complexity of the refrigerant) increases. Domanski and Didion (1993) evaluated the performance of nine alternatives to R22 including the impact of liquid-suction heat exchangers. Domanski et al. (1994) later extended the analysis by evaluating the influence of liquid-suction heat exchangers installed in vapor compression refrigeration systems considering 29 different refrigerants in a theoretical analysis. Bivens et al. (1994) evaluated a proposed mixture to substitute for R22 in air conditioners and heat pumps. Their analysis indicated a 6-7% improvement for the alternative refrigerant system When system modifications included a liquid-suction heat exchanger and counterfloW system heat exchangers (evaporator and condenser). Bittle et al. (1995a) conducted an experimental evaluation of a liquid-suction heat exchanger applied in a domestic refrigerator using R152a. The authors compared the system performance With that of a traditional R12-based system. Bittle et al. (1995b) also compared the ASHRAE method for predicting capillary tube performance (including the effects of liquid-suction heat exchangers) With experimental data. Predicted capillary tube mass floW rates Were Within 10% of predicted values and subcooling levels Were Within 1.7 C (3F) of actual measurements.This paper analyzes the liquid-suction heat exchanger to quantify its impact on system capacity and performance (expressed in terms of a system coefficient of performance, COP). The influence of liquid-suction heat exchanger size over a range of operating conditions (evaporating and condensing) is illustrated and quantified using a number of alternative refrigerants. Refrigerants included in the present analysis are R507A, R404A, R600, R290,R134a, R407C, R410A, R12, R22, R32, and R717. This paper extends the results presented in previous studies in that it considers neW refrigerants, it specifically considers the effects of the pressure drops,and it presents general relations for estimating the effect of liquid-suction heat exchangers for any refrigerant.Heat Exchanger EffectivenessThe ability of a liquid-suction heat exchanger to transfer energy from the Warm liquid to the cool vapor at steady-state conditions is dependent on the size and configuration of the heat transfer device. The liquid-suction heat exchanger performance, expressed in terms of an effectiveness, is a parameter in the analysis. The effectiveness of the liquid-suction heat exchanger is defined in equation (1):Where the numeric subscripted temperature (T) values correspond to locations depicted in Figure 1. The effectiveness is the ratio of the actual to maximum possible heat transfer rates. It is related to the surface area of the heat exchanger. A zero surface area represents a system Without a liquid-suction heat exchanger Whereas a system having an infinite heat exchanger area corresponds to an effectiveness of unity.The liquid-suction heat exchanger effects the performance of a refrigeration system by in fluencing both the high and loW pressure sides of a system. Figure 2 shoWs the key state points for a vapor compression cycle utilizing an idealized liquid-suction heat exchanger on a pressure-enthalpy diagram. The enthalpy of the refrigerant leaving the condenser (state 3) is decreased prior to entering the expansion device (state 4) by rejecting energy to the vapor refrigerant leaving the evaporator (state 1) prior to entering the compressor (state 2). Pressure losses are not shoWn. The cooling of the condensate that occurs on the high pressure side serves to increase the refrigeration capacity and reduce the likelihood of liquid refrigerant flashing prior to reaching the expansion device. On the loW pressure side, the liquid-suction heat exchanger increases the temperature of the vapor entering the compressor and reduces the refrigerant pressure, both of Which increase the specific volume of the refr igerant and thereby decrease the mass floW rate and capacity. A major benefit of the liquid-suction heat exchanger is that it reduces the possibility of liquid carry-over from the evaporator Which could harm the compressor. Liquid carryover can be readily caused by a number of factors that may include Wide fluctuations in evaporator load and poorly maintained expansiondevices (especially problematic for thermostatic expansion valves used in ammonia service).(翻译)冷却系统利用流体吸热交换器克来因教授,布兰顿教授, , 布朗教授威斯康辛州的大学–麦迪逊摘录加热装置在许多冷却系统中被用到,用以制冷时遗留在蒸发器中的冷却气体和离开冷凝器发热流体之间的能量的热交换.这些流体吸收或吸收热交换器,在一些情形中,他们降低了系统性能, 然而系统的某些地方却得到了改善. 虽然以前研究员已经调查了流体吸热交换器的性能, 但是这项研究可能从早先研究的三种方式被加以区别. 首先,这份研究开辟了一个无限的崭新的与流体吸热交换器有关联的群体.其次,这份研究拓宽了早先的分析包括新型制冷剂。

暖通毕业设计外文翻译

暖通毕业设计外文翻译

Thermal comfort in the future - Excellence and expectationP. Ole Fanger and Jørn ToftumInternational Centre for Indoor Environment and EnergyTechnical University of DenmarkAbstractThis paper predicts some trends foreseen in the new century as regards the indoor environment and thermal comfort. One trend discussed is the search for excellence, upgrading present standards that aim merely at an “acceptable” condition with a substantial number of dissatisfied. An important element in this connection is individual thermal control. A second trend is to acknowledge that elevated air temperature and humidity have a strong negative impact on perceived air quality and ventilation requirements. Future thermal comfort and IAQ standards should include these relationships as a basis for design. The PMV model has been validated in the field in buildings with HVAC systems that were situated in cold, temperate and warm climates and were studied during both summer and winter. In non-air-conditioned buildings in warm climates occupants may sense the warmth as being less severe than the PMV predicts, due to low expectations. An extension of the PMV model that includes an expectancy factor is proposed for use in non-air-conditioned buildings in warm climates. The extended PMV model agrees well with field studies inon-air-conditioned buildings of three continents.Keywords: PMV, Thermal sensation, Individual control, Air quality, AdaptationA Search for ExcellencePresent thermal comfort standards (CEN ISO 7730, ASHRAE 55) acknowledge that there are considerable individual differences between people’s thermal sensation and their discomfort caused by local effects, i.e. by air movement. In a collective indoor climate, the standards prescribe a compromise that allows for a significant number of people feeling too warm or too cool. They also allow for air velocities that will be felt as a draught by a substantial percentage of the occupants.In the future this will in many cases be considered as insufficient. There will be a demand for systems that allow all persons in a space to feel comfortable. The obvious wayto achieve this is to move from the collective climate to the individually controlled local climate. In offices, individual thermal control of each workplace will be common. The system should allow for individual control of the general thermal sensation without causing any draught or other local discomfort. We know the range of operative temperatures required in a workplace to satisfy nearly everybody (Wyon 1996; Fanger 1970) and we know the sensitivity to draught from a wide range of studies. A search for excellence involves providing all persons in a space with the means to feel thermally comfortable without compromise.Thermal Comfort and IAQPresent standards treat thermal comfort and indoor air quality separately, indicating that they are independent of each other. Recent research documents that this is not true (Fang et al. 1999; Toftum et al. 1998). The air temperature and humidity combined in the enthalpy have a strong impact on perceived air quality, and perceived air quality determines the required ventilation in ventilation standards. Research has shown that dry and cool air is perceived as being fresh and pleasant while the same composition of air at an elevated temperature and humidity is perceived as stale and stuffy. During inhalation it is the convective and evaporative cooling of the mucous membrane in the nose that is essential for the fresh and pleasant sensation. Warm and humid air is perceived as being stale and stuffy due to the lack of nasal cooling. This may be interpreted as a local warm discomfort in the nasal cavity. The PMV model is the basis for existing thermal comfort standards. It is quite flexible and allows for the determination of a wide range of air temperatures and humidities that result in thermal neutrality for the body as a whole. But the inhaled air would be perceived as being very different within this wide range of air temperatures and humidities. An example: light clothing and an elevated air velocity or cooled ceiling, an air temperature of 28ºC and a relative humidity of 60% may givePMV=0, but the air quality would be perceived as stale and stuffy. A simultaneous request for high perceived air quality would require an air temperature of 20-22oC and a modest air humidity. Moderate air temperature and humidity decrease also SBS symptoms (Krogstad et al. 1991, Andersson et al. 1975) and the ventilation requirement, thus saving energy during the heating season. And even with air-conditioning it may be beneficial and save energy during the cooling season.PMV model and the adaptive modelThe PMV model is based on extensive American and European experiments involving over a thousand subjects exposed to well-controlled environments (Fanger 1970). The studies showed that the thermal sensation is closely related to the thermal load on the effector mechanisms of the human thermoregulatory system. The PMV model predicts the thermal sensation as a function of activity, clothing and the four classical thermal environmental parameters. The advantage of this is that it is a flexible tool that includes all the major variables influencing thermal sensation. It quantifies the absolute and relative impact of these six factors and can therefore be used in indoor environments with widely differing HVAC systems as well as for different activities and different clothing habits. The PMV model has been validated in climate chamber studies in Asia (de Dear et al. 1991; Tanabe et al. 1987) as well as in the field, most recently in ASHRAE’s worldwide research in buildings with HVAC systems that were situated in cold, temperate and warm climates and were studied during both summer and winter (Cena et al. 1998; Donini et al. 1996; de Dear et al. 1993a; Schiller et al. 1988). The PMV is developed for steady-state conditions but it has been shown to apply with good approximation at the relatively slow fluctuations of the environmental parameters typically occurring indoors. Immediately after an upward step-wise change of temperature, the PMV model predicts well the thermal sensation, while it takes around 20 min at temperature down-steps (de Dear et al. 1993b).Field studies in warm climates in buildings without air-conditioning have shown, however, that the PMV model predicts a warmer thermal sensation than the occupants actually feel (Brager and de Dear 1998). For such non-air-conditioned buildings an adaptive model has been proposed (de Dear and Brager 1998). This model is a regression equation that relates the neutral temperature indoors to the monthly average temperature outdoors. The only variable is thus the average outdoor temperature, which at its highest may have an indirect impact on the human heat balance. An obvious weakness of the adaptive model is that it does not include human clothing or activity or the four classical thermal parameters that have a well-known impact on the human heat balance and therefore on the thermal sensation. Although the adaptive model predicts the thermal sensation quite well for non-air-conditioned buildings of the 1900’s located in warm parts of the world, the question remains as to how well it would suit buildings of new types in the future where the occupants have a different clothing behaviour and a different activity pattern.Why then does the PMV model seem to overestimate the sensation of warmth in nonair-conditioned buildings in warm climates? There is general agreement thatphysiological acclimatization does not play a role. One suggested explanation is that openable windows in naturally ventilated buildings should provide a higher level of personal control than in air-conditioned buildings. We do not believe that this is true in warm climates. Although an openable window sometimes may provide some control of air temperature and air movement, this applies only to the persons who work close to a window. What happens to persons in the office who work far away from the window? And in warm climates, the normal strategy in naturally ventilated buildings is to cool the building during the night and then close the windows some time during the morning when the outdoor temperature exceeds the indoor temperature. Another obstacle is of course traffic noise, which makes open windows in many areas impossible. We believe that in warm climates air-conditioning with proper thermostatic control in each space provides a better perceived control than openable windows.Another factor suggested as an explanation to the difference is the expectations of the occupants. We think this is the right factor to explain why the PMV overestimates the thermal sensation of occupants in non-air-conditioned buildings in warm climates. These occupants are typically people who have been living in warm environments indoors and outdoors, maybe even through generations. They may believe that it is their “destiny” to live in environments where they feel warmer than neutral. If given a chance they may not on average prefer an environment that is different from that chosen by people who are used to air-conditioned buildings. But it is likely that they would judge a given warm environment as less severe and less unacceptable than would people who are used toair-conditioning. This may be expressed by an expectancy factor, e, to be multiplied with PMV to reach the mean thermal sensation vote of the occupants of the actualnon-air-conditioned building in a warm climate. The factor e may vary between 1 and 0.5. It is 1 for air-conditioned buildings. For non-air-conditioned buildings, the expectancy factor is assumed to depend on the duration of the warm weather over the year and whether such buildings can be compared with many others in the region that are air-conditioned. If the weather is warm all year or most of the year and there are no or few otherair-conditioned buildings, e may be 0.5, while it may be 0.7 if there are many other buildings with air-conditioning. For non-air-conditioned buildings in regions where the weather is warm only during the summer and no or few buildings have air-conditioning, the expectancy factor may be 0.7 to 0.8, while it may be 0.8 to 0.9 where there are many air-conditioned buildings. In regions with only brief periods of warm weather during the summer, the expectancy factor may be 0.9 to 1. Table 1 proposes a first rough estimationof ranges for the expectancy factor corresponding to high, moderate and low degrees of expectation.A second factor that contributes erroneously to the difference between the PMV and actual thermal sensation votes in non-air-conditioned buildings is the estimated activity. In many field studies in offices, the metabolic rate is estimated on the basis of a questionnaire identifying the percentage of time the person was sedentary, standing, or walking. This mechanistic approach does not acknowledge the fact that people, when feeling warm, unconsciously tend to slow down their activity. They adapt to the warm environment by decreasing their metabolic rate. The lower pace in warm environments should be acknowledged by inserting a reduced metabolic rate when calculating the PMV.To examine these hypotheses further, data were downloaded from the database of thermal comfort field experiments (de Dear 1998). Only quality class II data obtained in non-air-conditioned buildings during the summer period in warm climates were used in the analysis. Data from four cities (Bangkok, Brisbane, Athens, and Singapore) were included, representing a total of more than 3200 sets of observations (Busch 1992, de Dear 1985, Baker 1995, de Dear et al. 1991). The data from these four cities with warm climates were also used for the development of the adaptive model (de Dear and Brager 1998).For each set of observations, recorded metabolic rates were reduced by 6.7% for every scale unit of PMV above neutral, i.e. a PMV of 1.5 corresponded to a reduction in the metabolic rate of 10%. Next, the PMV was recalculated with reduced metabolic rates using ASHRAE’s thermal comfort tool (Fountain and Huizenga 1997). The resulting PMV values were then adjusted for expectation by multiplication with expectancy factors estimated to be 0.9 for Brisbane, 0.7 for Athens and Singapore and 0.6 for Bangkok. As an average for each building included in the field studies, Figure 1 and Table 2 compare the observed thermal sensation with predictions using the new extended PMV model for warm climates.Figure 1. Thermal sensation in non-air-conditioned buildings in warm climates.Comparison of observed mean thermal sensation with predictions made using the new extension of the PMV model for non-air-conditioned buildings in warm climates. The linesare based on linear regression analysis weighted according to the number of responsesTable 2. Non-air-conditioned buildings in warm climates.Comparison of observed thermal sensation votes and predictions made using the newextension of the PMV model.The new extension of the PMV model for non-air-conditioned buildings in warmclimates predicts the actual votes well. The extension combines the best of the PMV andthe adaptive model. It acknowledges the importance of expectations already accounted forby the adaptive model, while maintaining the PMV model’s classical thermal parametersthat have direct impact on the human heat balance. It should also be noted that the newPMV extension predicts a higher upper temperature limit when the expectancy factor islow. People with low expectations are ready to accept a warmer indoor environment. Thisagrees well with the observations behind the adaptive model.Further analysis would be useful to refine the extension of the PMV model, and additional studies in non-air-conditioned buildings in warm climates in different parts of the world would be useful to further clarify expectation and acceptability among occupants. It would also be useful to study the impact of warm office environments on work pace and metabolic rate.ConclusionsThe PMV model has been validated in the field in buildings with HVAC systems, situated in cold, temperate and warm climates and studied during both summer and winter. In non-air-conditioned buildings in warm climates, occupants may perceive the warmth as being less severe than the PMV predicts, due to low expectations.An extension of the PMV model that includes an expectancy factor is proposed for use in non-air-conditioned buildings in warm climates.The extended PMV model agrees well with field studies in non-air-conditioned buildings in warm climates of three continents.A future search for excellence will demand that all persons in a space be thermally comfortable. This requires individual thermal control.Thermal comfort and air quality in a building should be considered simultaneously. A high perceived air quality requires moderate air temperature and humidity. AcknowledgementFinancial support for this study from the Danish Technical research Council is gratefully acknowledged.ReferencesAndersson, L.O., Frisk, P., Löfstedt, B., Wyon, D.P., (1975), Human responses to dry, humidified and intermittently humidified air in large office buildings. Swedish Building Research Document Series, D11/75.ASHRAE 55-1992: Thermal environmental conditions for human occupancy. American Society of Heating, Refrigerating and Air-conditioning Engineers, Inc.Baker, N. and Standeven, M. (1995), A Behavioural Approach to Thermal Comfort Assessment in Naturally Ventilated Buildings. Proceedings from CIBSE National Conference, pp 76-84.Brager G.S., de Dear R.J. (1998), Thermal adaptation in the built environment: a literature review. Energy and Buildings, 27, pp 83-96.Busch J.F. (1992), A tale of two populations: thermal comfort in air-conditioned and naturally ventilated offices in Thailand. Energy and Buildings, vol. 18, pp 235-249.CEN ISO 7730-1994: Moderate thermal environments - Determination of the PMV and PPD indices and specification of the conditions for thermal comfort. International Organization for Standardization, Geneva.Cena, K.M. (1998), Field study of occupant comfort and office thermal environments in a hot-arid climate. (Eds. Cena, K. and de Dear, R.). Final report, ASHRAE 921-RP, ASHRAE Inc., Atlanta.de Dear, R., Fountain, M., Popovic, S., Watkins, S., Brager, G., Arens, E., Benton, C., (1993a), A field study of occupant comfort and office thermal environments in a hot humid climate. Final report, ASHRAE 702 RP, ASHRAE Inc., Atlanta.de Dear, R., Ring, J.W., Fanger, P.O. (1993b), Thermal sensations resulting from sudden ambient temperature changes. Indoor Air, 3, pp 181-192.de Dear, R. J., Leow, K. G. and Foo, S.C. (1991), Thermal comfort in the humid tropics: Field experiments in air-conditioned and naturally ventilated buildings in Singapore. International Journal of Biometeorology, vol. 34, pp 259-265.de Dear, R.J. (1998), A global database of thermal comfort field experiments. ASHRAE Transactions, 104(1b), pp 1141-1152.de Dear, R.J. and Auliciems, A. (1985), Validation of the Predicted Mean Vote model of thermal comfort in six Australian field studies. ASHRAE Transactions, 91(2), pp 452- 468. de Dear, R.J., Brager G.S. (1998), Developing an adaptive model of thermal comfort and preference. ASHRAE Transactions, 104(1a), pp 145-167.de Dear, R.J., Leow, K.G., and Ameen, A. (1991), Thermal comfort in the humid tropics - Part I: Climate chamber experiments on temperature preferences in Singapore. ASHRAE Transactions 97(1), pp 874-879.Donini, G., Molina, J., Martello, C., Ho Ching Lai, D., Ho Lai, K., Yu Chang, C., La Flamme, M., Nguyen, V.H., Haghihat, F. (1996), Field study of occupant comfort and office thermal environments in a cold climate. Final report, ASHRAE 821 RP, ASHRAE Inc., Atlanta.Fang, L., Clausen, G., Fanger, P.O. (1999), Impact of temperature and humidity on chemical and sensory emissions from building materials. Indoor Air, 9, pp 193-201. Fanger, P.O. (1970), Thermal comfort. Danish Technical Press, Copenhagen, Denmark. Fouintain, M.E. and Huizenga, C. (1997), A thermal sensation prediction tool for use by the profession. ASHRAE Transactions, 103(2), pp 130-136.Humphreys, M.A. (1978), Outdoor temperatures and comfort indoors. Building Research and Practice, 6(2), pp 92-105.Krogstad, A.L., Swanbeck, G., Barregård, L., et al. (1991), Besvär vid kontorsarbete med olika temperaturer i arbetslokalen - en prospektiv undersökning (A prospective study of indoor climate problems at different temperatures in offices), Volvo Truck Corp., Göteborg, Sweden.Schiller, G.E., Arens, E., Bauman, F., Benton, C., Fountain, M., Doherty, T. (1988) A field study of thermal environments and comfort in office buildings. Final report, ASHRAE 462 RP, ASHRAE Inc., Atlanta.Tanabe, S., Kimura, K., Hara, T. (1987), Thermal comfort requirements during the summer season in Japan. ASHRAE Transactions, 93(1), pp 564-577.Toftum, J., Jørgensen, A.S., Fanger, P.O. (1998), Upper limits for air humidity for preventing warm respiratory discomfort. Energy and Buildings, 28(3), pp 15-23.Wyon, D.P. (1996) Individual microclimate control: required range, probable benefits and current feasibility. Proceedings of Indoor Air ’96, vol. 1, pp 1067-1072未来的热舒适性——优越性和期望值P. Ole Fanger 和Jørn Toftum国际中心室内环境与能源丹麦科技大学摘要本文预期一些可在新世纪所预见的关于热舒适的室内环境的趋势。

地源热泵设计

地源热泵设计

地源热泵设计1. 引言地源热泵(Ground Source Heat Pump,GSHP)是一种利用地热能源的环保供热、供冷系统。

与传统的取暖设备相比,地源热泵系统能够有效地提供高效能的制热和制冷,同时降低能源消耗和环境污染。

本文将讨论地源热泵系统的设计原理、主要组成部分和关键参数。

2. 设计原理地源热泵系统利用地下的恒定温度来实现供热和供冷。

它通过地下的地热能源,将热能转移到室内供暖或室外排热。

地源热泵系统包括地源换热器、热泵机组和室内盘管。

2.1 地源换热器地源换热器是地源热泵系统的关键组成部分之一。

它通常是埋在地下的一系列管道,用于吸收地下的热能或向地下释放热能。

地源换热器可以采用水平回填式或垂直回填式布置,具体选用哪种形式取决于地下空间的限制和地质条件。

2.2 热泵机组热泵机组是地源热泵系统的核心部分。

它由压缩机、膨胀阀、换热器和控制系统等组成。

其工作原理是通过压缩机将地下的低温热能提升到适宜的温度,然后通过换热器将热能传递给室内的盘管,使室内得到制热或制冷。

2.3 室内盘管室内盘管是地源热泵系统的末端设备。

它负责将热泵机组传递过来的热能释放到室内空气中,实现供热或供冷效果。

室内盘管可以是风管式或地暖式,具体选用哪种形式取决于室内空间的布局和需要。

3. 设计参数设计地源热泵系统时,需要考虑一系列的参数,以确保系统的正常运行和高效能输出。

3.1 地源温度地源温度是地源热泵系统设计的首要参数。

地下的温度随季节变化比较缓慢,通常在8℃至15℃之间。

设计时应根据实际地下温度数据进行分析和计算,以确定最佳的设计参数。

3.2 热泵机组容量热泵机组的容量需要根据室内需求进行合理计算。

一般来说,热泵机组的制热和制冷容量应根据室内的热负荷计算得出,以确保系统能够满足室内的舒适需求。

3.3 地源换热器的长度和管径地源换热器的长度和管径直接影响系统的换热效果。

根据地下的地质条件和热泵机组的容量,可以通过热传导计算确定地源换热器的最佳长度和管径。

(完整)暖通空调专业外文翻译

(完整)暖通空调专业外文翻译

英文文献Air Conditioning SystemsAir conditioning has rapidly grown over the past 50 years, from a luxury to a standard system included in most residential and commercial buildings。

In 1970, 36%of residences in the U。

S。

were either fully air conditioned or utilized a room air conditioner for cooling (Blue, et al。

, 1979)。

By 1997, this number had more than doubled to 77%, and that year also marked the first time that over half (50.9%) of residences in the U。

S。

had central air conditioners (Census Bureau, 1999)。

An estimated 83% of all newhomes constructed in 1998 had central air conditioners (Census Bureau, 1999)。

Air conditioning has also grown rapidly in commercial buildings。

From 1970 to 1995, the percentage of commercial buildings with air conditioning increased from 54 to 73% (Jackson and Johnson, 1978, and DOE, 1998).Air conditioning in buildings is usually accomplished with the use of mechanical or heat-activated equipment. In most applications, the air conditioner must provide both cooling and dehumidification to maintain comfort in the building。

地源热泵系统模型与仿真

地源热泵系统模型与仿真

地源热泵系统模型与仿真地源热泵系统模型与仿真地源热泵(Ground Source Heat Pump,GSHP)是一种高效而环保的供热和供冷系统。

它利用地下的稳定温度来调节室内温度,并能通过回收废热实现节能。

为了实现地源热泵系统的设计和优化,研究人员开发了各种模型和仿真工具。

本文将介绍地源热泵系统的基本原理,探讨其模型和仿真方法,并分析其在实际应用中的意义。

地源热泵系统由地下换热器、热泵机组、热交换器和用户终端组成。

地下换热器通过埋设在地下的地源热井,利用地下恒定的温度来提供稳定的热源。

地下换热器的设计涉及地下水流率、管道布局等因素,可以利用模型预测和优化其性能。

热泵机组利用压缩机和制冷剂循环来实现热量的转移,从而提供供热或供冷能力。

热交换器用于在供热和供冷模式之间切换,以满足用户需求。

用户终端通过热交换器将热量传送到室内或室外,实现热量的传递或抽取。

为了实现对地源热泵系统的建模和仿真,可以采用物理模型和数学模型。

物理模型是基于地源热泵系统的实际工作原理,通过建立能量平衡方程和热传导方程来描述热量的传输和转移过程。

物理模型可以更加准确地预测地源热泵系统的性能,但也需要大量的参数和实验数据来支持。

数学模型是通过研究地源热泵系统的规律和特征来建立的,通常采用代数方程或微分方程来描述热量的流动和转换。

数学模型可以通过简化和抽象地源热泵系统的复杂性来实现计算和优化,但也可能忽略一些实际工作中的细节。

地源热泵系统的仿真是指利用计算机软件或模拟工具来模拟和分析地源热泵系统的运行和性能。

仿真可以通过改变参数和运行条件来预测系统的响应和性能,从而指导系统设计和运行。

在仿真过程中,可以使用物理模型或数学模型来描述地源热泵系统,并结合实际工作条件和数据进行计算。

仿真工具可以帮助工程师和设计师快速评估不同设计和优化方案的效果,从而减少实际试验和调整的成本和时间。

地源热泵系统的模型和仿真对于其设计和优化具有重要意义。

首先,模型和仿真可以帮助理解和分析地源热泵系统的工作原理和性能。

关于地源热泵技术的毕业论文开题报告

关于地源热泵技术的毕业论文开题报告

一、选题的依据及意义:1 •依据:进入90年代后,我国的居住环境和工业生产环境都已广泛地应用热水供应装置,热水供应装置已成为现代学校居住必备。

90年代中期,由于大中城市电力供应紧张,供电部门开始重视需求管理及削峰填谷,热泵供热技术提到了议事日程。

近年来,由于能源结构的变化,促进了地源热泵供热机组的快速发展。

随着生产和科技的不断发展,人类对地源热泵供热技术也进行了一系列的改进,同时也在积极研究环保、节能的地源热泵供热产品和技术,现在利用成熟的电子技术来进行综合的控制,并和太阳能结合更注意能源的综合利用、节能、保护环境及趋向自然的舒适环境必然是今后发展的主题。

2. 意义:地源热泵技术,是利用地下的土壤、地表水、地下水温相对稳定的特性,,通过消耗电能,在冬天把低位热源中的热量转移到需要供热或加温的地方,在夏天还可以将室内的余热转移到低位热源中,达到降温或制冷的目的。

地源热泵不需要人工的冷热源,可以取代锅炉或市政管网等传统的供暖方式和中央空调系统。

冬季它代替锅炉从土壤、地下水或者地表水中取热,向建筑物供暖;夏季它可以代替普通空调向土壤、地下水或者地表水放热给建筑物制冷。

同时,它还可供应生活用水,可谓一举三得,是一种有效地利用能源的方式。

通常根据热泵的热源(heat source)和热汇(heat sink)(冷源)的不同,主要分成三类:空气源热泵系统(air-source heat pump) ashp水源热泵系统(water- source heat pump) wshp地源热泵系统(gro und- source heat pump)gshp平时还有人把热泵系统按照一次和二次介质的不同,分别叫做:空气---水热泵系统水---空气热泵系统水---水热泵系统空气---空气热泵系统这些都是把热源、热汇以及空调系统的传递介质也包括进来分类形成的。

为了和国际标准接轨,我们还是应该依照国际惯例来命名。

在1997年由美国的ashrae (美国采暖、制冷与空调工程师学会)统一了标准术语,无论是wshp、gshp都叫做gshp--地源热泵系统。

太阳能-地源热泵的热源性能大学毕业论文英文文献翻译及原文

太阳能-地源热泵的热源性能大学毕业论文英文文献翻译及原文

毕业设计(论文)外文文献翻译文献、资料中文题目:太阳能-地源热泵的热源性能文献、资料英文题目:文献、资料来源:文献、资料发表(出版)日期:院(部):专业:班级:姓名:学号:指导教师:翻译日期: 2017.02.14外文文献翻译(译成中文1000字左右):【主要阅读文献不少于5篇,译文后附注文献信息,包括:作者、书名(或论文题目)、出版社(或刊物名称)、出版时间(或刊号)、页码。

提供所译外文资料附件(印刷类含封面、封底、目录、翻译部分的复印件等,网站类的请附网址及原文】太阳能-地源热泵的热源性能Y. Bi1,2, L. Chen1* and C. Wu3本论文研究了中国天津冬季里的太阳能-地源热泵的太阳能与地源性能。

结果被用于设计和分析的太阳能集热器和地面热交换器。

太阳能-地源热泵在这个地区的使用可行性是成立的。

关键词:太阳能,地源热泵,可行性。

介绍地源热泵(GSHP)利用地下相对稳定的温度作为热源或水槽提供热源或调节空气。

GSHP 系统寻求利用常规空气-空气热泵系统的两方面可用的功能。

首先,地下环境温度缓慢地变化,归结于其高的热质量,导致了相对稳定的源或者散热器的温度而不受较大的极限。

其次,被地面吸收的太阳能在整个冬季可以热源。

自从地源热泵的观念在二十世纪四十年代被发展,大量的理论和实验工作都完成了,实验研究审查了具体的地源热泵系统和现场数据。

理论研究已经集中于用数值方法模拟地下盘管换热器以及研究参数对系统性能的影响。

太阳能-地源热泵(SGSHP)采用太阳能集热器和大地作为热源开始发展于1982年。

热泵实验系统用垂直双螺旋线圈(VSDC)地下换热器(GHX)为太阳能-地源热泵(SGSHP)利用低品位能源,这种方法已经被作者们所创造。

(图1)蒸汽压缩热泵的加热负荷和性能系数(COP)取决于蒸发温度和热源温度。

SGSHP采用太阳能集热器和大地作为热源,因此,其应用主要是依靠太阳能和土壤源性能。

在本论文中,中国天津的气象数据被用来分析SGSHP在该区域的应用可行性。

地源热泵系统中英文对照外文翻译文献

地源热泵系统中英文对照外文翻译文献

中英文对照外文翻译(文档含英文原文和中文翻译)原文:Source heat pump system simulation and design abstract Summarized the recent years source heat pump system simulation and the design aspect research and the progress.First has given the source heat pump system various parts modelling aspect progress, including the vertical pipe installation geothermy heat interchanger, the single well circulatory system as well as several kind of assistance heat dissipating arrangement which uses in the place source heat pump mix system.Next, discusses the scene determination in-depth ground hot natural technology.Third, introduction vertical pipe installation geothermy heat interchanger design method.Finally, gives in the design source heat pump system uses the system simulation several application example. Key word:Heat pump; Geothermy heat interchanger; Hot nature; Mix system; Model; Design; Simulation1.synopses looked from thermodynamics viewpoint that, uses the source hotwork in the air-conditioning system for the heat source or the heat sink is appealing.This is because, looked from the whole year, its temperature ratio environment dry bulb or the wet-bulb temperature approach (needs) in the room the temperature.Based on this reason, the source heat pump system has the potential compared with the air source heat pump system in the high efficiency.In actual situation, source heat pump system because does not have the equipment to expose in exterior environment, the flower in the service aspect expense is quite low (Cane, et al. 19982.Although already had some source heat pump system technology to obtain thedevelopment in the Scandinavian peninsula, but in its commercial development use was actually does well in US.This is mainly is because already has a very big housing air-conditioning system market in US.Because its system has the low energy consumption and the low operating cost already proved has attracted very many es electricity the peak value in American very many areas to be decided by the air conditioning electricity consumption. Enables some power equipment company regarding this reason to be interested very much to this system, they hoped through uses such system to reduce for the electric power demand.Some small business organization and the public department's already studied this kind of technology the application.The source heat pump system attracts some school manager as a result of it low operating cost, and has the more and more many school use.Already gave GHPC in US about the place source heat pump technology practical application some example research detail.3.Meets down in the paper in the part we first can give the source heat pumpsystem various parts modelling aspect progress, including the vertical pipe installation geothermy heat interchanger, the water source heat pump, the single well circulatory system as well as several kind of assistance heat dissipating arrangement which uses in the place source heat pump mix system.Because must design the underground heat interchanger first to have to understand the geothermy the attribute, this paper second part introducedbriefly the determination in-depth ground hot natural model, this method is by to measured the test hole temperature responded the scene test method expands comes.In the paper third part, will be able to introduce will design the vertical pipe installation geothermy heat interchanger with the software the method.Finally, gives in the design source heat pump system uses the system simulation several application example, including mixes the GSHP system and the frostproof GSHP system design.4.The 2.GSHP system model constitutes the GSHP system generally iscomposed by the water source heat pump and the underground heat interchanger, regarding mixes the GSHP system, but also includes several kind of assistance heat dissipating arrangement.These simulation equipment is covered in undeshuts the circulation underground heat interchanger to shut the circulation double barrel systems to be possible to use the horizontal pipe installation or the vertical pipe installation.Vertical pipe installation system as a result of it high heat transfer efficiency by people many uses.This kind of type closed cycle heat interchanger sets at into the diameter by a root is 75mm~150mm the drill hole U tube is composed.These drill holes after set at into the U tube with the earth backfill which drills or, more universal, the entire kondow pads with the thin mud.Is in the milk usually is avoids the ground water the pollution moreover causing the heat transfer pipeline with to contact completely reaches the greatly good heat transfer effect.Is commonly used the diameter is the 22mm~33mmhigh density polyethylene manages (HDPE) in the system pipe installation.Punch depth generally between 30m~120m.Two kind of simulation complexity are very interesting.First, the survey underground heat interchanger user's smallest input design method is may take in the unit time.Next, its can forecast in for several hours (or short time curve) because the building load continuously change has what influence to the underground heat interchanger the simulation pattern also is also is may take.This theory permission and uses electricity the demand forecast to the system energy consumption.Because both method take has been presented by Eskilson(1987)development model as the foundation in this paper, the Eskison method could first discuss, then will be to by Yavuzturk and the Spitler development simulation pattern description. (1999)2.1.1 Eskison research techniquesEskison (1987) aims at the pair hole the ambient temperature distribution definite question solution uses the means which the logic analysis and the mathematical analysis unify.Regarding the initial condition and in the boundary condition constant even soil the pair hole related value establishment radial direction - axial coordinates, the use transient state finite difference equation carries on the two-dimensional value computation individually.The pipe wall and the mud and so on the individual drill hole essential factor calorific capacity is likely is neglected.The single drill hole temperature field through overlaps obtains the entire drill hole scope.The entire drill hole scope temperature response is transformed to a group of non-linear temperature feedback factor, was called makes the G- function.This G- function possibly causes the place pair opening wall temperature change situation computation which the specific heat input causes correspondingly with some time in into.As soon as passes through the drill hole scope the feedback to indicate to the steps and ladders quantity of heat feedback with the G- function that, any random temperature feedback function can because of let above a series of step function the temperature feedback/output decision, moreover superimposes to each gradient function feedback.This process expressed regarding four month-long temperature feedbacks by the graphical representation method in Figure 1.2.1.2 simulation model here said the simulation model majority of details already introduced by Yavuzturk and Spitler.In this paper will be able to give its brief description.This model essential target is the application in the construction energy analysis, this model can forecast the system energy consumption take each hour as the unit.This model nationality will consummate by the Eskilson theory develops is discussed in here.The Master G- function increased the forecast frequency to an hour several times.Eskilson uses for to determine the G- function the data model not to besuitable for the short time curve survey, uses another kind of data model to survey a place pair hole short time internal heat feedback/output pulse the temperature response.Regarding the short time in hot pulse, inside and outside the radial direction position pair hole hot shift affects the axial position hot shift is much bigger than.From this, has produced one kind of two-dimensional radial direction constant volume model.The details see also Yavuzturk, et al. (1999).2.2 vertical circular hole well vertical circular hole well uses in directly carrying on the heat change with the ground.One kind used for to study the vertical circular hole well performance the data model already to research and develop, it was composed by two parts: Pair hole constitution node model, in nearby ground water flowing and ground heat transfer constant volume model.This kind of model utilization including the heat transfer which causes to the ground water flowing is clear about processing (Rees, et al.2003).This kind of model may inspect vertical circular Kong Jing the performance in the use influence and the vital significance.Its performance is most has in following several parameters sensitively: Current capacity, pair hole length, ground heat conductivity and hydraulic pressure conductivity.2.3 water source heat pump Jin and Spitler(2002a) has invented one kind of parameter estimate water source heat pump model.This kind of model carries on the thermodynamic analysis to the freezing circulation, the specific heat exchange model is simpler, simultaneously is more precise than the freezing circulation compressor model.In the second paper (Jin, et al.2002b), carries on the expansion to this model, including maneuver type air compressor sub-model and use antifreeze step.In the manufacture manufacturer table of contents data narrated in model each kind of parameter which the multivariable optimization algorithm estimates.Jin(2002) in detail narrated the parameter which the multivariable optimization algorithm and pares the equation - being suitable type model which before then produces, the water source heat pump model is more precise.Jin(2002) also introduced one kind of similar water source heat pump model.In 2.4 mixed style GSHP system thermal compensation source heat pump system the pair hole cost is the system cost important part, but it mainly is decided by thelocal geology condition.This kind of equipment mainly uses in refrigerating in the building.Is bad in this kind of ground thermal conductivity, drill hole condition crude place, water source heat pump system cost quite expensive.For all this, we may adopt the primary cost with to be able the effect compromise means, reduces the pair hole scope, installs the assistance heat dissipating arrangement in the heat pump water pipe.Such system is called the mixed source heat pump system.In the mix system water pipe has each kind of different type heat dissipating arrangement, for instance the cooling tower, brings the heat interchanger shallow pool, the hydraulic pressure heating surface or is called the bridge level.Chiasson(2002a) has invented the shallow pool model, its principle is: Because shuts the circulation heat interchanger, needs to install the counter-flow heat transfer installment in the water level surface mounting natural heat transfer installment foundation.Chiasson(2000b) simultaneously also invented one kind to be suitable in the hydraulic pressure heating surface or is called the bridge level the finite difference model.This kind of model even can imitate the snow melting process.The above these model use experimental assistance heat dissipating arrangement, obtains the approval in Oklahoma State University.1.soil quantity of heat characteristic scene determination survey in-depthground heat conductivity regarding the place source heat pump system very important.The pair hole width length mainly is decided by in-depth ground hot nature.The determination in-depth ground heat conductivity traditional method is first definite around the pair hole the ground type.After the determination, may determine its heat conductivity through "Double barrel Heat pump System design Handbook" about the ground type material (EPRI1989).According to the report, in the ground information heat conductivity has a more widespread value, therefore could find one kind of more precise surveying to decide the ground heat conductivity method to be better. The in-depth ground heat conductivity cannot the immediate determinant, only be able to infer through the tepid transformation measuring method, but also must use some geothermy transmission pattern, for instance linear water source law (Ingersoll and Plass1948; Mogensen1983) orcylindrical water source law (Carslaw and Jaeger1947).Interesting is they alsohas the opposite use - - to determine its hot nature by the ground performance,but is not determines its performance by the ground hot nature.Although thelinear water source law and the cylindrical water source law may in turnutilize in the reckoning ground heat conductivity, but still needed to makesome simple hypotheses, because its influence result was not easy toes the pair hole particular data model, to place pair holegeometry and thermal fluid, pipeline.The mud as well as the ground hotnature carries on the detailed description, may reduce the element of certaintywhich the simple hypothesis creates.Thus, can have a more precise estimate tothe geothermy conductivityThe ground temperature responded the analysis step has two basic types: Analytic method (Witte, et al.2002) and parameter estimate law (Austin1998; Austin et al.2000; Shonder and Beck1999).Witte et al(2002) uses the linear water source law and the indefinite analytic method carries on the scene test to the ground heat conductivity.The Austinet al(2000) parameter estimate law is surveys one with the vertical drill hole transient state two-dimensional data constant volume pattern known to change the time the heat flux input ground temperature response.The Nelder Mead simplex operation principle is used for to excavate the ground and the mud heat conductivity most valueable use, that is the temperature which surveys the experiment responded and the estimate temperature between responded the interpolation reduces the threshold. The survey ground heat conductivity test installation is by Eklof, Gehlin(1996) and Austin(1998) invents independently.Figure 5 is Austin et the al. (2000) invention test system schematic drawing.The test installation places in the trailer which may drive.The pair hole installment 50 hour experimental proofs by one is satisfied.Short experimental time suits the human regard extremely, moreover is possibly the subject which the future will study.译文:地源热泵系统的模拟与设计摘要:总结了近年来地源热泵系统的模拟和设计方面的研究和进展。

外文翻译

外文翻译

毕业设计(论文)译文题目名称:闭环地源热泵系统学院名称:班级:学号:学生姓名:指导教师:2014年03 月闭环地源热泵系统闭环地源热泵系统相对于常规暖通空调系统有更多地有点。

例如,在制冷季节,他们可以收集积累在地上的可再生地面热量或复原建筑热量。

此外,由于其在制热和制冷具有较高的性能系数(COP)而被美国能源部和美国环境保护局在最节能、环保的制热和制冷系统中注意到。

最后,在大多数地区发现的混合发电结构中他们比传统暖通空调系统排放更少的温室气体。

正在被考虑的闭环土壤源热泵系类型在图1中被展现出来。

这个闭环系统代表着最流行的配置之一。

传热流体被泵输送到一系列垂直钻孔,其中热量收集(放出)则相应流体的温度会增加(减少)。

钻孔深度是依赖于项目的,但通常是在50米-150米的范围。

如截面图中所示,钻孔通常充满了灌浆来促进流体和土地的传热和保护国家规定需要保护的地下水蓄水层。

流体然后返回到建筑,在流体回路中热泵收集(放出)热量,从而减少(增加)的流体温度。

在任何给定的时间,一些热泵可能运行供热模式,而其他的可能在冷却模式。

因此,它是可能使能量通过流体循环从建筑的一个部分转移到另一个。

最后,在某些情况下,它有利于设计所谓的混合动力系统,辅助冷却,减少地面热交换器的长度。

尽管有环境优势,一些设计工程师仍不愿指定这些系统。

主要存在两个原因,首先,这些系统的资本和维护成本通常被认为是高于传统系统。

在现实中,安装系统的成本数据1,2,3不完全支持这一论断。

此外,在一些成本控制选项中,如混合动力系统,可以减少地面热交换器的长度(和成本)。

第二个原因,这是本文的重点,就是有些设计师不完全了解在峰值条件,并在很长一段时间在钻孔和在地下发生的相对复杂的现象。

热泵的性能数据地下换热器的设计是对热泵性能审查的重要数据。

热泵的性能系数(COP)和热泵的能力取决于几个参数,如流体的流速和温度。

COP定义为有用能量(无论是在冷却或加热)的功率输入到单元的比率(用于运行压缩机和风扇)。

地源热泵系统设计与应用实例

地源热泵系统设计与应用实例

地源热泵系统设计与应用实例地源热泵(Ground Source Heat Pump,简称GSHP)是一种利用地下土壤或地下水体的地热资源进行热能交换的热泵系统。

它通过地下热交换器吸收或释放热量,实现供暖、制冷和热水供应等功能。

本文将介绍地源热泵系统的设计原理,并结合实际案例来探讨其应用。

一、地源热泵系统设计原理地源热泵系统的设计包括地热资源评估、热泵机组选型、热源井设计、热交换器布置和管路设计等环节。

以下是地源热泵系统设计的一般流程:1. 地热资源评估在选择地源热泵系统时,需要先评估地下土壤或地下水体的温度、含水量等参数,以确定热源的可利用性。

通常来说,地下温度较稳定,适合作为地热资源。

2. 热泵机组选型根据建筑的供暖、制冷和热水需求,选择合适的热泵机组。

不同的机组类型、规格和能力会直接影响地源热泵系统的性能和效果。

3. 热源井设计热源井是地源热泵系统的核心组成部分,它通过垂直或水平的方式与地下热源进行热交换。

井深、井径以及井间距等参数需要根据具体情况进行合理设计。

4. 热交换器布置根据建筑的供热或供冷需求,将热泵机组与热源井之间的热交换器布置在合适的位置,以确保热量的高效传递和利用。

5. 管路设计地源热泵系统中的管路设计也需要充分考虑,包括管径、管材、管道布局等因素。

好的管路设计可以提高系统的热能输送效率。

二、地源热泵系统应用实例以下是一个典型的地源热泵系统应用实例,以某高层办公楼为例:1. 项目背景该办公楼位于城市中心,是一座多层高层建筑。

由于市区供暖系统的限制,传统的锅炉供暖方式存在一定的问题,因此选择地源热泵系统进行供暖和制冷。

2. 地热资源评估通过勘测和分析,确定地下水体的平均温度为15℃,且含水量丰富,具备较好的地热资源。

3. 热泵机组选型根据建筑的需求和设计条件,选择了一台功率为100KW的地源热泵机组,具备供暖和制冷双重功能。

4. 热源井设计根据地下水体的水位和季节变化情况,设计了一口深度为60米的垂直热源井,井径为0.5米。

暖通空调专业 毕业设计外文翻译3

暖通空调专业 毕业设计外文翻译3

外文翻译(1)Refrigeration System Performance using Liquid-Suction Heat ExchangersS. A. Klein, D. T. Reindl, and K. BroWnellCollege of EngineeringUniversity of Wisconsin - MadisonAbstractHeat transfer devices are provided in many refrigeration systems to e xchange energy betWeen the cool gaseous refrigerant leaving the evaporator and Warm liquid refrigerant exiting the condenser. These liquid-suction or suction-line heat exchangers can, in some cases, yield improved system performance While in other cases they degrade system performance. Although previous researchers have investigated performance of liquid-suction heat exchangers, this study can be distinguished from the previous studies in three Ways. First, this paper identifies a neW dimensionless group to correlate performance impacts attributable to liquid-suction heat exchangers. Second, the paper extends previous analyses to include neW refrigerants. Third, the analysis includes the impact of pressure drops through the liquid-suction heat exchanger on system performance. It is shoWn that reliance on simplified analysis techniques can lead to inaccurate conclusions regarding the impact of liquid-suction heat exchangers on refrigeration system performance. From detailed analyses, it can be concluded that liquid-suction heat exchangers that have a minimal pressure loss on the loW pressure side are useful for systems using R507A, R134a, R12, R404A, R290, R407C, R600, and R410A. The liquid-suction heat exchanger is detrimental to system performance in systems using R22, R32, and R717.IntroductionLiquid-suction heat exchangers are commonly installed in refrigeration systems With the intent of ensuring proper system operation and increasing system performance.Specifically, ASHRAE(1998) states that liquid-suction heat exchangers are effective in:1) increasing the system performance2) subcooling liquid refrigerant to prevent flash gas formation at inlets to expansion devices3) fully evaporating any residual liquid that may remain in the liquid-suction prior to reaching the compressor(s)Figure 1 illustrates a simple direct-expansion vapor compression refrigeration system utilizing a liquid-suction heat exchanger. In this configuration, high temperature liquid leaving the heat rejection device (an evaporative con denser in this case) is subcooled prior to being throttled to the evaporator pressure by an expansion device such as a thermostatic expansion valve. The sink for subcoolingthe liquid is loW temperature refrigerant vapor leaving the evaporator. Thus, the liquid-suction heat exchanger is an indirect liquid-to-vapor heat transfer device. The vapor-side of the heat exchanger (betWeen the evaporator outlet and the compressor suction) is often configured to serve as an accumulator thereby further minimizing the risk of liquid refrigerant carrying-over to the compressor suction. In cases Where the evaporator alloWs liquid carry-over, the accumulator portion of the heat exchanger Will trap and, over time, vaporize the liquid carryover by absorbing heat during the process of subcooling high-side liquid.BackgroundStoecker and Walukas (1981) focused on the influence of liquid-suction heat exchangers in both single temperature evaporator and dual temperature evaporator systems utilizing refrigerant mixtures. Their analysis indicated that liquid-suction heat exchangers yielded greater performance improvements When nonazeotropic mixtures Were used compared With systems utilizing single component refrigerants or azeoptropic mixtures. McLinden (1990) used the principle of corresponding states to evaluate the anticipated effects of neW refrigerants. He shoWed that the performance of a system using a liquid-suction heat exchanger increases as the ideal gas specific heat (related to the molecular complexity of the refrigerant) increases. Domanski and Didion (1993) evaluated the performance of nine alternatives to R22 including the impact of liquid-suction heat exchangers. Domanski et al. (1994) later extended the analysis by evaluating the influence of liquid-suction heat exchangers installed in vapor compression refrigeration systems considering 29 different refrigerants in a theoretical analysis. Bivens et al. (1994) evaluated a proposed mixture to substitute for R22 in air conditioners and heat pumps. Their analysis indicated a 6-7% improvement for the alternative refrigerant system When system modifications included a liquid-suction heat exchanger and counterfloW system heat exchangers (evaporator and condenser). Bittle et al. (1995a) conducted an experimental evaluation of a liquid-suction heat exchanger applied in a domestic refrigerator using R152a. The authors compared the system performance With that of a traditional R12-based system. Bittle et al. (1995b) also compared the ASHRAE method for predicting capillary tube performance (including the effects of liquid-suction heat exchangers) With experimental data. Predicted capillary tube mass floW rates Were Within 10% of predicted values and subcooling levels Were Within 1.7 C (3F) of actual measurements.This paper analyzes the liquid-suction heat exchanger to quantify its impact on system capacity and performance (expressed in terms of a system coefficient of performance, COP). The influence of liquid-suction heat exchanger size over a range of operating conditions (evaporating and condensing) is illustrated and quantified using a number of alternative refrigerants. Refrigerants included in the present analysis are R507A, R404A, R600, R290,R134a, R407C, R410A, R12, R22, R32, and R717. This paper extends the results presented in previous studies in that it considers neW refrigerants, it specifically considers the effects of the pressure drops,and it presents general relations for estimating the effect of liquid-suction heat exchangers for any refrigerant.Heat Exchanger EffectivenessThe ability of a liquid-suction heat exchanger to transfer energy from the Warm liquid to the cool vapor at steady-state conditions is dependent on the size and configuration of the heat transfer device. The liquid-suction heat exchanger performance, expressed in terms of an effectiveness, is a parameter in the analysis. The effectiveness of the liquid-suction heat exchanger is defined in equation (1):Where the numeric subscripted temperature (T) values correspond to locations depicted in Figure 1. The effectiveness is the ratio of the actual to maximum possible heat transfer rates. It is related to the surface area of the heat exchanger. A zero surface area represents a system Without a liquid-suction heat exchanger Whereas a system having an infinite heat exchanger area corresponds to an effectiveness of unity.The liquid-suction heat exchanger effects the performance of a refrigeration system by in fluencing both the high and loW pressure sides of a system. Figure 2 shoWs the key state points for a vapor compression cycle utilizing an idealized liquid-suction heat exchanger on a pressure-enthalpy diagram. The enthalpy of the refrigerant leaving the condenser (state 3) is decreased prior to entering the expansion device (state 4) by rejecting energy to the vapor refrigerant leaving the evaporator (state 1) prior to entering the compressor (state 2). Pressure losses are not shoWn. The cooling of the condensate that occurs on the high pressure side serves to increase the refrigeration capacity and reduce the likelihood of liquid refrigerant flashing prior to reaching the expansion device. On the loW pressure side, the liquid-suction heat exchanger increases the temperature of the vapor entering the compressor and reduces the refrigerant pressure, both of Which increase the specific volume of the refr igerant and thereby decrease the mass floW rate and capacity. A major benefit of the liquid-suction heat exchanger is that it reduces the possibility of liquid carry-over from the evaporator Which could harm the compressor. Liquid carryover can be readily caused by a number of factors that may include Wide fluctuations in evaporator load and poorly maintained expansiondevices (especially problematic for thermostatic expansion valves used in ammonia service).(翻译)冷却系统利用流体吸热交换器克来因教授,布兰顿教授, , 布朗教授威斯康辛州的大学–麦迪逊摘录加热装置在许多冷却系统中被用到,用以制冷时遗留在蒸发器中的冷却气体和离开冷凝器发热流体之间的能量的热交换.这些流体吸收或吸收热交换器,在一些情形中,他们降低了系统性能, 然而系统的某些地方却得到了改善. 虽然以前研究员已经调查了流体吸热交换器的性能, 但是这项研究可能从早先研究的三种方式被加以区别. 首先,这份研究开辟了一个无限的崭新的与流体吸热交换器有关联的群体.其次,这份研究拓宽了早先的分析包括新型制冷剂。

暖通空调 地源热泵中英文论文

暖通空调 地源热泵中英文论文

中文关于暖通空调系统的节能问题随着经济的迅速发展,能源和环境问题日益尖锐。

在特别炎热的夏天,我们都切身地体会到了电力的紧张。

可以预见,这种状况在今后还会出现,并且会日趋严重。

1、暖通空调领域节能的重要性和可行性随着社会的发展,建筑能耗在总能耗中所占的比例越来越大,在发达国家已达到40%,据统计在湖南省也达到27.8%。

在城市远高于这个比例。

而在建筑能耗里,用于暖通空调的能耗又占建筑能耗的30%-50%,且在逐年上升。

随着人均建筑面积的不断增大,暖通空调系统的广泛应用,用于暖通空调系统的能耗将进一步增大。

这势必会使能源供求矛盾的进一步激化。

另一方面,现有的暖通空调系统所使用的能源基本上是高品位的不可再生能源,其中电能占了绝对比例。

对这些能源的大量使用,使得地球资源日益匮乏,同时也带来严重的环境问题,如在我国的一些地区酸雨、飘尘问题呈日益严重之势,对生态环境和可持续发展带来了很大影响。

以湖南长沙地区为例,2003年夏季电力系统最大负荷大约为160万千瓦,据有关部门推算,其中空调系统的负荷就占了约60万千瓦。

在最热的夏天,如果对暖通空调系统采取节能措施,不仅可以大大缓解电力紧张状况,同时对于降低不可再生能源的消耗、保护生态环境、维持可持续发展、振兴湖南经济等都有着重要的意义。

根据暖通空调行业的研究成果,现有空调系统的能耗是惊人的,如果采用节能技术,现有空调系统节能20%-50%完全可能。

显然,如果对长沙地区的空调系统和建筑系统采用节能措施,那么即使遇到今夏那样的炎热天气,长沙也不会超过现有电力系统峰值而停电了。

2、暖通空调领域节能的途径与方法科学技术的不断进步,使暖通空调领域新的技术不断出现,我们可以通过多种方法实现暖通空调系统的节能。

2.1、精心设计暖通空调系统,使其在高效经济的状况下运行暖通空调系统特别是中央空调系统是一个庞大复杂的系统,系统设计的优劣直接影响到系统的使用性能。

例如系统往往都是按最大负荷设计的,而实际运行基本上是在部分负荷下运行,如果系统各部分的设计不能满足部分负荷运行的要求,那系统的能耗是很大的。

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<<地源热泵系统的模拟与设计>>摘要:总结了近年来地源热泵系统的模拟和设计方面的研究和进展。

首先给出了地源热泵系统各部件建模方面的进展,包括竖直埋管地热换热器、单井循环系统以及在地源热泵混合系统中采用的几种辅助散热装置。

其次,讨论现场测定深层岩土热物性的技术。

第三,介绍竖直埋管地热换热器的设计方法。

最后,给出在设计地源热泵系统中采用系统模拟的几个应用实例。

关键词:热泵;地热换热器;热物性;混合系统;模型;设计;模拟1.简介从热力学的观点来看,在空调系统中利用地源热作为热源或者冷源是吸引人的。

这是因为,从全年来看,其温度比环境干球或湿球温度更接近于室内(所需要)的温度。

基于这个原因,地源热泵系统较之空气源热泵系统在高效率上更具有潜力。

在实际情况中,源热泵系统由于没有设备暴露在外部的环境中,花在维修方面的费用是比较低的(Cane, et al. 1998).虽然已经有一些地源热泵系统技术在斯堪的那维亚半岛得到发展,但是其商业上的开发利用却是在美国做得最好。

这是主要是因为在美国已经存在着一个很大的住宅空调系统市场。

其系统由于有着较低的能耗和低运行费用已经证明吸引了很多业主。

在美国很多地区用电峰值取决于空调用电量。

对于这个原因使得一些电力设备公司对这个系统很感兴趣,他们希望通过使用这样的系统来减少对电力的需求。

一些小型商业机构和公共部门已经研究出这种技术的应用。

地源热泵系统由于其较低的运行费用而吸引一些学校主管,并有越来越多的学校使用。

在美国关于地源热泵技术实际应用的一些实例研究细节已经交给GHPC。

在论文接下来的部分中我们首先会给出地源热泵系统各部件建模方面的进展,包括竖直埋管地热换热器、水源热泵、单井循环系统以及在地源热泵混合系统中采用的几种辅助散热装置。

由于要设计地下换热器首先就要了解地热的属性,这篇论文的第二部分简要介绍了确定深层岩土热物性的模型,这种方法是由对测试孔温度反应的现场测试法引申而来的。

在论文的第三部分,将会介绍一下用软件来设计竖直埋管地热换热器的方法。

最后,给出在设计地源热泵系统中采用系统模拟的几个应用实例,其中包括混合 GSHP 系统和防冻GSHP系统的设计。

2.GSHP系统模型构成GSHP 系统一般由水源热泵和地下换热器组成,对于混合GSHP 系统,还包括几种辅助散热装置。

这些模拟的设备在下面被覆盖。

2.1闭循环地下换热器闭循环双管系统可采用水平埋管或垂直埋管。

垂直埋管系统由于其较高的换热效率而被人们较多的采用。

这种类型的闭式循环换热器由一根根置入直径为75MM~150MM 钻孔的U 型管组成。

这些钻孔在置入U 型管后用钻出来的土回填或者,更普遍,整个孔都用薄泥浆填塞。

灌浆通常是避免地下水的污染而且使换热管道与完全接触以达大良好的换热效果。

常用于系统埋管的是直径为22MM~33MM 的高密度聚乙烯管 (HDPE)。

打孔深度一般在30M~120M 之间。

两种模拟的复杂性很有意思。

首先,测量地下换热器在单位时间内用户的最小输入的设计方法是可取的。

其次,其能预测数小时内(或较短的时距)由于建筑物负荷的连续变化对地下换热器造成何影响的模拟模式也是也是可取的。

这一理论允许对系统能量消耗和用电需求预测。

因为两者的方法以被 Eskilson(1987) 发展的模型为基础在这论文中呈现了, Eskison 的方法将会首先被讨论,接着是对被 Yavuzturk 和 Spitler 发展的模拟模式的描述.(1999)2.1.1 Eskison 的研究方法Eskison (1987)针对地耦孔周围温度分布的确定问题的解决办法是采用逻辑分析和数学解析相结合的办法。

对于初始条件和边界条件恒定的均匀土壤中的单个地耦孔的相关数值建立径向-轴向坐标,使用瞬态有限差分方程进行二维数值计算。

像管壁和泥浆等个别钻孔要素的热容量是被忽略的。

单个钻孔的温度场通过重叠来获得整个钻孔范围。

整个钻孔范围的温度回应被转换到一组非线性的温度反馈因数,被称做G-函数。

这个G-函数使得与某一时间内的特定热量输入相应引起的地耦孔壁的温度变化情况的计算成为可能。

一经钻孔范围的反馈对阶梯热量的反馈用G-函数来表示, 任何的任意热反馈函数能被藉由在一系列的阶梯函数之上让热反馈/输出决定, 而且叠加对每个梯度函数的反馈。

这一过程对于四个月的热反馈以图示的方法在图 1中表示。

基本的热脉冲(从零到1Q )是指历经整个过程4个月后的热量峰值,其值'1Q=1Q 。

次级脉冲'2Q =2Q -1Q ,为3个月期间后的峰值。

同理,'3Q =3Q -2Q 为两个月期末峰值,最后,'4Q =4Q -3Q 指一个月后的热量峰值。

因此,任何时间地耦孔壁的温度都能够由这四个阶梯函数计算确定。

从数学角度来看,在第n th 时期的末期,受位置因素影响的地耦孔壁的温度如下:∑=----+=n i b s i n i i ground borehole Hr t t t g k Q Q T T 111),(2)(π 其中:t =时间(s))9/(2a H t s ==时间范围H =孔井深度(m)k =岩土导热系数(W/(m.k))borehole T =孔井平均温度(℃)ground T =岩土稳态温度(℃)Q=阶梯热反馈脉冲(W/m)b r = 孔径(m)i =时间梯度结束指数2.1.2仿真模型这里所说的仿真模型的大部分细节已经由Yavuzturk 和 Spitler 所介绍。

在本文中将会给出其简要的描述。

这个模型的主要目标是应用在建筑能量分析上,这模型能够以每小时为单位来预测系统能量消耗。

此模型籍由Eskilson 理论完善而发展将在这里被讨论。

Master 的G-函数把预测频率增加至一小时数次。

Eskilson 用来测定G-函数的数据模型不适用于短时距测量,采用另一种数据模型来测算一个地耦孔短时间内热反馈/输出脉冲的温度反应。

对于短时间内的热脉冲来说,径向位置地耦孔内外的热转移比轴向位置的热转移影响大得多。

由此,产生了一种二维径向定容模型。

详情参见Yavuzturk,et al.(1999).2.2垂直圆形孔井垂直圆形孔井用于直接与岩土进行热交换。

一种用来研究垂直圆形孔井性能的数据模型已经研发了,它由两部分组成:地耦孔构成的节点模型,附近地下水流动和岩土中热传递定容模型。

这种模型的运用包括对地下水流动导致的热传递的明确处理(Rees,et al.2003) 。

这种模型可以考察垂直圆形孔井的性能在使用中的影响和重要意义。

其性能在以下几个参量中是最具敏感的:流量,地耦孔长度,岩土热传导率和水压传导率。

2.3水源热泵Jin和Spitler(2002a)发明了一种参量估算水源热泵模型。

这种模型对冷冻循环进行热力学分析,比热交换模型更简单,同时比冷冻循环压缩机模型更为精确。

在第二篇论文(Jin,et al.2002b)中,对这一模型进行扩展,包括回旋式空气压缩机的子模型和使用防冻剂的步骤。

制造厂商的目录数据中叙述了多变量优化算法估算出的模型中的各种参量。

Jin(2002)详细叙述了多变量优化算法和估算出的参量。

比起在此之前生产的方程-适宜类型模型,水源热泵模型更为精确。

Jin(2002)还介绍了一种类似的水源热泵模型。

2.4混合式GSHP系统的热量补偿地源热泵系统中地耦孔的成本是系统成本的重要部分,但它主要取决于当地地质状况。

这种装置主要用于制冷建筑物中。

在这种岩土的导热性差,钻孔条件简陋的地方,水源热泵系统的成本的比较昂贵。

尽管如此,我们可以采取初次成本与能效折中的办法,缩小耦孔范围,在热泵水管内安装辅助散热装置。

这样的系统称为混合型地源热泵系统。

混合系统的水管中有各种不同类型的散热装置,比如冷却塔,带换热器的浅水池,液压加热面或者叫桥层。

Chiasson(2002a)发明了浅水池模型,其原理是:由于闭循环换热器,需要在水层表面安装天然热传递装置的基础上安装对流换热装置。

Chiasson(2000b)同时还发明了一种适用于液压加热面或者叫桥层的有限差分模型。

这种模型甚至能够模仿积雪融化过程。

以上这些模型使用试验性的辅助散热装置,在俄克拉荷马州大学得到认可。

3.土壤热量特性的现场测定测量深层岩土的热传导性对于地源热泵系统来说至关重要。

地耦孔的宽度长度主要取决于深层岩土的热物性。

测定深层岩土的热传导性的传统方法是首先确定地耦孔周围岩土的类型。

确定后,可以通过《双管热泵系统设计手册》中关于岩土类型的资料来测定其热传导性(EPRI1989)。

据报道,岩土信息中的热传导性有更广泛的价值,因此能找到一种更精确地测定岩土热传导性的方法就更好了。

深层岩土的热传导性不能直接测定,只能通过温热变换测定法来推断,还需利用一些地热传递模式,比如线形水源法(Ingersoll and Plass1948;Mogensen1983)或者柱形水源法(Carslaw and Jaeger1947)。

有趣的是它们还有相反的用途——由岩土的性能来测定其热物性,而不是由岩土的热物性来测定其性能。

虽然线形水源法和柱形水源法可以反过来运用于测算岩土热传导性,但是仍然需要做一些简单假设,因为其影响结果是不易测定的。

采用地耦孔详细数据模型,对地耦孔几何学和热流体,管道。

泥浆以及岩土的热物性进行详细描述,可以减少简单假设造成的不确定因素。

这样,对地热传导性就会有一个更精确的估算。

岩土温度反应的分析步骤有两中基本类型:分析法(Witte,et al.2002)和参量估算法(Austin1998;Austin et al.2000;Shonder and Beck1999)。

Witte et al(2002)用线形水源法和不确定分析法对岩土热传导性进行现场测试。

Austinet al(2000)的参量估算法是用垂直钻孔的瞬态二维数据定容模式来测算一个已知的变时间的热流量输入的岩土温度反应。

Nelder Mead 的单工运算法则被用来发掘岩土和泥浆热传导性的最有价值的用途,那就是把实验测量的温度反应和估算的温度反应之间的差值减小到最低限度。

测量岩土热传导性的实验装置是由Eklof,Gehlin(1996)和Austin(1998)自主发明的。

图5是Austin et al.(2000)发明的测试系统的示意图。

实验装置放在一个可以拖动的拖车里。

地耦孔安装被一个长达50 小时的试验证明是满意的。

一个较短的试验时间是非常合人心意的, 而且可能是将来研究的主题。

外文翻译:<<Source heat pump system simulation and design abstract>> Summarized the recent years source heat pump system simulation and the design aspect research and the progress.First has given the source heat pump system various parts modelling aspect progress, including the vertical pipe installation geothermy heat interchanger, the single well circulatory system as well as several kind of assistance heat dissipating arrangement which uses in the place source heat pump mix system.Next, discusses the scene determination in-depth ground hot natural technology.Third, introduction vertical pipe installation geothermy heat interchanger design method.Finally, gives in the design source heat pump system uses the system simulation several application example. Key word:Heat pump; Geothermy heat interchanger; Hot nature; Mix system; Model; Design; Simulation1.synopses looked from thermodynamics viewpoint that, uses the source hotwork in the air-conditioning system for the heat source or the heat sink is appealing.This is because, looked from the whole year, its temperature ratio environment dry bulb or the wet-bulb temperature approach (needs) in the room the temperature.Based on this reason, the source heat pump system has the potential compared with the air source heat pump system in the high efficiency.In actual situation, source heat pump system because does not have the equipment to expose in exterior environment, the flower in the service aspect expense is quite low (Cane, et al. 19982.Although already had some source heat pump system technology to obtain thedevelopment in the Scandinavian peninsula, but in its commercial development use was actually does well in US.This is mainly is because already has a very big housing air-conditioning system market in US.Because its system has the low energy consumption and the low operating cost already proved has attracted very many es electricity the peak value in American very many areas to be decided by the air conditioning electricity consumption. Enables some power equipment company regarding this reason to be interested very much to this system, they hoped through uses suchsystem to reduce for the electric power demand.Some small business organization and the public department's already studied this kind of technology the application.The source heat pump system attracts some school manager as a result of it low operating cost, and has the more and more many school use.Already gave GHPC in US about the place source heat pump technology practical application some example research detail.3.Meets down in the paper in the part we first can give the source heat pumpsystem various parts modelling aspect progress, including the vertical pipe installation geothermy heat interchanger, the water source heat pump, the single well circulatory system as well as several kind of assistance heat dissipating arrangement which uses in the place source heat pump mix system.Because must design the underground heat interchanger first to have to understand the geothermy the attribute, this paper second part introduced briefly the determination in-depth ground hot natural model, this method is by to measured the test hole temperature responded the scene test method expands comes.In the paper third part, will be able to introduce will design the vertical pipe installation geothermy heat interchanger with the software the method.Finally, gives in the design source heat pump system uses the system simulation several application example, including mixes the GSHP system and the frostproof GSHP system design.4.The 2.GSHP system model constitutes the GSHP system generally iscomposed by the water source heat pump and the underground heat interchanger, regarding mixes the GSHP system, but also includes several kind of assistance heat dissipating arrangement.These simulation equipment is covered in undeshuts the circulation underground heat interchanger to shut the circulation double barrel systems to be possible to use the horizontal pipe installation or the vertical pipe installation.Vertical pipe installation system as a result of it high heat transfer efficiency by people many uses.This kind of type closed cycle heat interchanger sets at into the diameter by a root is 75mm~150mm the drill hole Utube is composed.These drill holes after set at into the U tube with the earth backfill which drills or, more universal, the entire kondow pads with the thin mud.Is in the milk usually is avoids the ground water the pollution moreover causing the heat transfer pipeline with to contact completely reaches the greatly good heat transfer effect.Is commonly used the diameter is the 22mm~33mmhigh density polyethylene manages (HDPE) in the system pipe installation.Punch depth generally between 30m~120m.Two kind of simulation complexity are very interesting.First, the survey underground heat interchanger user's smallest input design method is may take in the unit time.Next, its can forecast in for several hours (or short time curve) because the building load continuously change has what influence to the underground heat interchanger the simulation pattern also is also is may take.This theory permission and uses electricity the demand forecast to the system energy consumption.Because both method take has been presented by Eskilson(1987) development model as the foundation in this paper, the Eskison method could first discuss, then will be to by Yavuzturk and the Spitler development simulation pattern description. (1999)2.1.1 Eskison research techniquesEskison (1987) aims at the pair hole the ambient temperature distribution definite question solution uses the means which the logic analysis and the mathematical analysis unify.Regarding the initial condition and in the boundary condition constant even soil the pair hole related value establishment radial direction - axial coordinates, the use transient state finite difference equation carries on the two-dimensional value computation individually.The pipe wall and the mud and so on the individual drill hole essential factor calorific capacity is likely is neglected.The single drill hole temperature field through overlaps obtains the entire drill hole scope.The entire drill hole scope temperature response is transformed to a group of non-linear temperature feedback factor, was called makes the G- function.This G- function possibly causes the place pair opening wall temperature change situation computation which the specific heat input causes correspondingly with some timein into.As soon as passes through the drill hole scope the feedback to indicate to the steps and ladders quantity of heat feedback with the G- function that, any random temperature feedback function can because of let above a series of step function the temperature feedback/output decision, moreover superimposes to each gradient function feedback.This process expressed regarding four month-long temperature feedbacks by the graphical representation method in Figure 1.2.1.2 simulation model here said the simulation model majority of details already introduced by Yavuzturk and Spitler.In this paper will be able to give its brief description.This model essential target is the application in the construction energy analysis, this model can forecast the system energy consumption take each hour as the unit.This model nationality will consummate by the Eskilson theory develops is discussed in here.The Master G- function increased the forecast frequency to an hour several times.Eskilson uses for to determine the G- function the data model not to be suitable for the short time curve survey, uses another kind of data model to survey a place pair hole short time internal heat feedback/output pulse the temperature response.Regarding the short time in hot pulse, inside and outside the radial direction position pair hole hot shift affects the axial position hot shift is much bigger than.From this, has produced one kind of two-dimensional radial direction constant volume model.The details see also Yavuzturk, et al. (1999).2.2 vertical circular hole well vertical circular hole well uses in directly carrying on the heat change with the ground.One kind used for to study the vertical circular hole well performance the data model already to research and develop, it was composed by two parts: Pair hole constitution node model, in nearby ground water flowing and ground heat transfer constant volume model.This kind of model utilization including the heat transfer which causes to the ground water flowing is clear about processing (Rees, et al.2003).This kind of model may inspect vertical circular Kong Jing the performance in the use influence and the vital significance.Its performance is most has in following several parameters sensitively: Current capacity, pair hole length, ground heat conductivity and hydraulic pressure conductivity.2.3 water source heat pump Jin and Spitler(2002a) has invented one kind of parameter estimate water source heat pump model.This kind of model carries on the thermodynamic analysis to the freezing circulation, the specific heat exchange model is simpler, simultaneously is more precise than the freezing circulation compressor model.In the second paper (Jin, et al.2002b), carries on the expansion to this model, including maneuver type air compressor sub-model and use antifreeze step.In the manufacture manufacturer table of contents data narrated in model each kind of parameter which the multivariable optimization algorithm estimates.Jin(2002) in detail narrated the parameter which the multivariable optimization algorithm and pares the equation - being suitable type model which before then produces, the water source heat pump model is more precise.Jin(2002) also introduced one kind of similar water source heat pump model.In 2.4 mixed style GSHP system thermal compensation source heat pump system the pair hole cost is the system cost important part, but it mainly is decided by the local geology condition.This kind of equipment mainly uses in refrigerating in the building.Is bad in this kind of ground thermal conductivity, drill hole condition crude place, water source heat pump system cost quite expensive.For all this, we may adopt the primary cost with to be able the effect compromise means, reduces the pair hole scope, installs the assistance heat dissipating arrangement in the heat pump water pipe.Such system is called the mixed source heat pump system.In the mix system water pipe has each kind of different type heat dissipating arrangement, for instance the cooling tower, brings the heat interchanger shallow pool, the hydraulic pressure heating surface or is called the bridge level.Chiasson(2002a) has invented the shallow pool model, its principle is: Because shuts the circulation heat interchanger, needs to install the counter-flow heat transfer installment in the water level surface mounting natural heat transfer installment foundation.Chiasson(2000b) simultaneously also invented one kind to be suitable in the hydraulic pressure heating surface or is called the bridge level the finite difference model.This kind of model even can imitate the snow melting process.The above these model use experimental assistance heat dissipating arrangement, obtains the approval in Oklahoma State University.1.soil quantity of heat characteristic scene determination survey in-depthground heat conductivity regarding the place source heat pump system veryimportant.The pair hole width length mainly is decided by in-depth ground hot nature.The determination in-depth ground heat conductivity traditionalmethod is first definite around the pair hole the ground type.After thedetermination, may determine its heat conductivity through "Double barrelHeat pump System design Handbook" about the ground type material(EPRI1989).According to the report, in the ground information heatconductivity has a more widespread value, therefore could find one kind ofmore precise surveying to decide the ground heat conductivity method to bebetter. The in-depth ground heat conductivity cannot the immediatedeterminant, only be able to infer through the tepid transformation measuringmethod, but also must use some geothermy transmission pattern, for instancelinear water source law (Ingersoll and Plass1948; Mogensen1983) orcylindrical water source law (Carslaw and Jaeger1947).Interesting is they alsohas the opposite use - - to determine its hot nature by the ground performance,but is not determines its performance by the ground hot nature.Although the linear water source law and the cylindrical water source law may in turnutilize in the reckoning ground heat conductivity, but still needed to makesome simple hypotheses, because its influence result was not easy toes the pair hole particular data model, to place pair holegeometry and thermal fluid, pipeline.The mud as well as the ground hotnature carries on the detailed description, may reduce the element of certaintywhich the simple hypothesis creates.Thus, can have a more precise estimate to the geothermy conductivityThe ground temperature responded the analysis step has two basic types: Analytic method (Witte, et al.2002) and parameter estimate law (Austin1998; Austin et al.2000; Shonder and Beck1999).Witte et al(2002) uses the linear water source law and the indefinite analytic method carries on the scene test to the ground heat conductivity.The Austinet al(2000) parameter estimate law is surveys one with the vertical drill hole transient state two-dimensional data constant volume pattern knownto change the time the heat flux input ground temperature response.The Nelder Mead simplex operation principle is used for to excavate the ground and the mud heat conductivity most valueable use, that is the temperature which surveys the experiment responded and the estimate temperature between responded the interpolation reduces the threshold. The survey ground heat conductivity test installation is by Eklof, Gehlin(1996) and Austin(1998) invents independently.Figure 5 is Austin et the al. (2000) invention test system schematic drawing.The test installation places in the trailer which may drive.The pair hole installment 50 hour experimental proofs by one is satisfied.Short experimental time suits the human regard extremely, moreover is possibly the subject which the future will study.。

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