高温气冷堆多头螺旋管式蒸汽发生器的设计与计算

摘要

摘要

蒸汽发生器是高温气冷反应堆的主要设备之一。高温反应堆产生的热量被氦气冷却剂吸收，在蒸汽发生器中传递给二次回路。氦气自上而下流过发生器，水在外力作用下进入发生器并产生水蒸汽自下而上流过传热面管束。

蒸汽发生器的传热面由多头螺旋管组成。螺旋管束有很多优点：它可以充分利用换热器的空间；没有急剧的弯曲，不会增加气或水侧的压力损耗，同时也简化了工艺，减少了焊点；对受热膨胀有很好的适应性；有很高的传热系数。

在很多工业领域中，螺旋管式热交换器都得到广泛的应用，它可适用于单相流体、蒸汽以及可压缩流体的流动。螺旋管束可用于化学反应器、储藏罐和一些核反应发生器。在大规模的能源动力系统中，它还可用作太阳能集电器的接受器。

多头螺旋管式换热器在换热面结构设计、传热和压降计算方面报道的文献较少。本文从实际工程设计出发，对多头螺旋管式换热器的设计进行了研究，提出了多头螺旋管束受热面结构的设计方法，推荐了螺旋管内外的传热系数和压降的计算关系式。根据所提出设计方法和螺旋管内外的传热系数和压降的计算关系式对260MW蒸汽发生器进行了设计计算。

关键词热交换器，传热，压降，螺旋管

东北电力学院学士学位论文

ABSTRACT

The steam generator is one of the important equipments in the high-temperature gas-cooled reactor. The heat generated in the high-temperature reactor and absorbed by the helium coolant is transferred the secondary circuit in steam generator. The helium flows downward through the steam generator. The water is forced into the steam generator and the resuting water/steam flow is directed upwards through the heating surface bundles.

The heating surface of the steam generator is composed of several helically wound tubes(helicoils).There are a number of obvious advantages in banks of helical tubes: they permit a very good utilization of the expensive casing volume; they do not require sharp tube bends，which increase the pressure loss on the steam/water side and which also may impose manufacturing problems or may require additional welds; and finally， they exhibit high heat transfer coefficients.

Many industries use helically and spirally coiled heat exchanger tubes for single-phase， evaporating， and condensing flows. Coils are used in chemical reactors， storage tanks， and on some nuclear stream generators. In a new application， a coiled tube has been proposed for the receiver of a concentrating-type solar collector in a large-scale power generation system.

Referenses on design of heated surface structure、calculation of heat transfer and pressure drop for heat exchanger with multi-start helical coiled tubes are less. Design method of the heat exchanger with multi-start helical coiled tubes is researched to meet of engineering practice. The structure design of multi-start helical tubes bundle is present. The correlations to caculate heat transfer coefficient and pressure drop for the inside and out side of helical coild tubes are commended.

Key Word:heat exchanger，heat transfer，pressure drop，helical coiled tubes

目录

目录

摘要 (Ⅰ)

Abstrct (Ⅱ)

第一章绪论 (1)

1.1课题的研究背景及意义 (1)

1.2换热器的发展和现状 (3)

1.2.1换热器概述 (3)

1.2.2换热器研究工作进展 (4)

1.3本课题要完成的工作 (5)

第二章多头螺旋管式蒸汽发生器的设计方法 (6)

2.1设计原则及基本工作原理 (6)

2.2 换热面结构的设计方法 (7)

2.3 设计计算步骤 (11)

第三章关于设计的推荐公式 (12)

3.1总传热系数 (12)

3.2 管外（壳侧）放热系数h o (13)

3.3.1 无变时的放热系数 (16)

3.3.2有相变时的放热系数 (16)

3.4.1摩擦阻力压降计算 (18)

3.4.2局部阻力压降计算 (19)

3.4.3重位压降计算 (20)

3.4.4加速压降计算 (20)

3.5管外侧压力损失 (22)

3.6多值性的校验 (22)

3.7管间脉动的校验 (23)

3.8节流圈的选取 (26)

第四章260MW高温气冷堆蒸汽发生器的设计 (27)

4.1设计参数 (27)

4.2结构设 (27)

4.3 260MW高温气冷堆蒸汽发生器设计计算书 (28)