WRC 107_Local Stresses in Spherical and Cylindrical Shells due to External Loadings_2002 _部分1
WRCMS
y
-MC VL
xA
-MT
z
C
DP
A D
B
B
Fx force
P RADIALLY INWARD
Fy force
VL FROM B -> A
Fz force -VC FROM C - > D
Mx moment -MT TORSIONAL
My moment -MC CIRCUMFERNETIAL
Mz moment -ML LONGITUDINAL
Torsional
Moment MT
Lots of charts to look up
Then fill in tables
Then Use, Mohr Circle
Байду номын сангаас
Max Shear Stress
σ 2
(σx, τ)
2θ σ 1
σy τ
τ σx θ
(σ1 + σ2)/2
Stress Intensity σ1 - σ2
5. Radial Nozzle in the shell center.
WRC Parameters for this example:
1. d/D: 0.167 2. L/D: 1.67 3. D/T: 96 4. d/T: 16 5. d/t: 24
( < 0.3 ) ( > 1.5 ) ( <= 600) ( >= 5 ) ( > 20 )
– Self-limiting – stress can reduce after local yielding.
– Higher allowable (approx 3*Savg)
WRC Bulletin 537 及其 勘误表
To: All WRC Subscribers and purchasers of WC 537 From: WRC Publication Staff Date: Friday, August 19, 2011 Subject: WRC Bulletin 537 Errata The following errata have been reported.Page Section/Table/Figure DescriptionDate Corrected 6August 1965 ForewordCorrect range for beta from 0.375 to 0.55/31/201116 3.4 Page number for nondimensional curves for spherical shells shouldbe page 43 5/31/201125 4.4.1 Page number for nondimensional curves for cylindrical shells shouldbe page 91 5/31/201139 Table 5Table 5 – for computation of Nø/(P/Rm) currently states 3C or 4C,should only State 3C – Note Figure 3C is properly labeled. 6/1/2011 39 Table 5Table 5 – for computation of Nx/(P/Rm) currently states 3C or 4C,should only State 4C – Note Figure 4C is properly labeled 6/1/2011 51 Curve Fit Table forSP-1 Incorrect column name in last column currently shows My shouldshow Ny7/5/2011 54,55 Figure SP-3 and Curve Fit TableIncorrect range for right side axis for NiT(RmT)1/2/Mcosq6/21/201174,75 Figure SM-3 and Curve Fit Table Curve fit for data was adjusted to prevent negative values for Y withinvalid range for X 7/22/201186 Figure SM-9 Adjusted the placement of the labels for Nx and My for easier reading 7/22/201189 Curve Fit Table forSM-10 Equation shown is not the equation used to calculate the curve fit6/21/2011101 Figure 4A and CurveFit TableMissing figure and table2/28/2011118 Figure 3B Title is incorrect should be longituidinal moment not circumferential 5/31/2011120 Figure 4B Title is incorrect should be longituidinal moment not circumferential 5/31/2011128, 129Figure 1C-1 Original and Curve Fit Table Incorrect range for Y4/4/2011130, 131 Figure 1C-1 Extrapolated and Curve Fit Table Incorrect range for Y 4/4/2011 184Figure B-2Incorrect values for x axis8/19/2011If you have any further questions,please send an email to subscribers@ . If any additional errata items are reported, this file will be updated. Please check/wrc/BULLETIN%20537_Errata_pages.pdf for any updates.The Welding Research Council, Inc.WRC 537Local Stresses in Spherical and Cylindrical Shells Due To External Loading5FOREWORDTo WRC Bulletin 107, March 1979 Update of August 1965 Original VersionWelding Research Council Bulletin No. 107 has been one of the most widely used bulletins ever published by WRC. The original bulletin was published in August 1965. Since that time, a revised printing was issued in December 1968; a second revised printing was issued in July 1970; a third revised printing was released in April 1972; and a June 1977 reprint of the third revised printing was issued. As sometimes happens with publications of this type, some errors were detected and then corrected in subsequent revised printings.In this March 1979 Revision of Bulletin 107, there are some additional revisions and clarifications. The formulations for calculation of the combined stress intensity, S, in Tables 2, 3, and 5 have been clarified. Changes in labels in Figures 1C-1, 2C-1, 3C , and 4C have been made and the calculated stresses for Model "R" in Table A-3 and Model "C-l" in Table A-4 have been revised accordingly. The background for the change in labels is given in a footnote on p. 66.Present plans call for a review and possible extension of curves to parameters which will cover the majority of openings in nuclear containment vessels and large storage tanks. Plans are to extend /R T from 300 to 600 and to extend /d D range from 0.003 to 0.10 for the new /R T range, review available test data to establish limits of applicability, and develop some guidance for pad reinforcements.Long range plans are to review shell theory in general, and Bijlaard's method in particular. The goal is to extend the /R T up to 1200 for a /d D up to 0.1. This will include large deflection theory and other nonlinear effects. In addition, available computer programs will be studied in hope of developing one which will be an appropriate supplement to Bijlaard's method. Finally, a review will be made of limit loads related to large /R T and small /d D .J.R, Farr, Chairman PVRC Design DivisionThe Welding Research Council, Inc.WRC 5376Local Stresses in Spherical and Cylindrical Shells Due To External LoadingFOREWORDTo WRC Bulletin 107, August 1965 Original VersionSeveral years ago, the Pressure Vessel Research Committee sponsored an analytical and experimental research program aimed at providing methods of determining the stresses in pressure vessel nozzle connections subjected to various forms of external loading. The analytical portion of this work was accomplished by Prof. P. P. Bijlaard of Cornell University, and was reported in References 1 to 8 inclusive. Development of the theoretical solutions involved a number of simplifying assumptions, including the use of shallow shell theory for spherical vessels and flexible loading surfaces for cylindrical vessels. These circumstances limited the potential usefulness of the results to /i i d D , ratios of perhaps 0.33 in the case of spherical shells and 0.25 in the case of cylindrical shells. Since no data were available for the larger diameter ratios, Prof. Bijlaard later supplied data, at the urging of the design engineers, for the values of 0.375β= and0.50 (/i i d D , ratios approaching 0.60) for cylindrical shells, as listed on page 12 of Reference 10.In so doing, Prof. Bijlaard included a specific warning concerning the possible limitations of these data, as follows: "The values for these large loading surfaces were computed on request of several companies. It should be remembered, however, that they actually apply to flexible loading surfaces and, for radial load, to the center of the loading surface. It should be understood that using these values for the edge of the attachment, as was recommended for small loading surfaces, may be unconservative.''Following completion of the theoretical work, experimental work was undertaken in an effort to verify the theory, the results of which were published in References 17 and 18. Whereas this work seemingly provided reasonable verification of the theory, it was limited to relatively small /i i d D ratios-0.10 in the case of spherical shells and 0.126 in the case of cylindrical shells. Since virtually no data, either analytical or experimental, were available covering the larger diameter ratios, the Bureau of Ships sponsored a limited investigation of this problem in spheres, aimed at a particular design problem, and the Pressure Vessel Research Committee undertook a somewhat similar investigation in cylinders. Results of this work have recently become available emphasizing the limitations in Bijlaard 's data on cylindrical shells, particularly as it applies to thin shells over the "extended range " (page 12 of Reference 10).Incident to the use of Bijlaard's data for design purposes, it has become apparent that design engineers sometimes have difficulty in interpreting or properly applying this work. As a result of such experience, PVRC has felt it desirable that all of Bijlaard's work be summarized in convenient, "cook-book" form to facilitate its use by design engineers. However, before this document could be issued, the above mentioned limitations became apparent, presenting an unfortunate dilemma, viz., the test data indicate that the calculated data are partially inadequate, but the exact nature and magnitude of the error is not known, nor is any better analytical treatment of the problem available (for cylinders).Under these circumstances, it was decided that the best course was to proceed with issuing the "cook-book," extending Bijlaard's curves as best we can on the basis of available test data. This decision was based on the premise that all of the proposed changes would be toward the conservative (or "safe") side and that design engineers would continue to use Bijlaard 's extended range data unless some alternative were offered. The following paper is therefore presented in the hope that it will facilitate the use of Bijlaard's work by design engineers. Every effort has been made to point out any known limitations in the work and to explain the exact nature of the changes which have been made to Bijlaard's original curves and data; however, users are warned that the resulting work is not necessarily adequate for all cases. It is the hope of the Subcommittee that additional theoretical work can be undertaken to provide more adequate data on various phases of this problem.F. S.G. Williams, ChairmanPVRC Subcommittee on Reinforced Openings and External LoadingsThe Welding Research Council, Inc.WRC 537Local Stresses in Spherical and Cylindrical Shells Due To External Loading153.3.2 Stresses Resulting From Overturning Moment,M3.3.2.1Radial Stresses (x σ)a) STEP 1. Using the applicable values of *,,U and ρϒ, read off the dimensionless membrane force()/xN M from the applicable curve which will be found in one of the following figures:Figure SR-3 or SM-1 to SM-10, inclusive.b) STEP 2. By the same procedure used in STEP 1 above, read off the value of dimensionless bendingmoment ()/M M from the applicable curve. This value will be found in the same figureused in STEP 1.c) STEP 3. Using the applicable values of ,,m M R and T , calculate the radial membrane stress()/x N Tby:x N T ⎞=⎝(12) d) STEP 4. By a procedure similar to that used in STEP 3, calculate the radial bending stress()26xMT, thus:26x M T ⎞=⎝ (13) e) STEP 5. Combine the radial membrane and bending stresses by use of the general stress equation(paragraph 2) together with the proper choice of sign (see Table 1); i.e.,26x x x nb N MK K T Tσ=± (14) 3.3.2.2Tangential Stress (y σ)Follow the five steps outlined in 3.3.2.1, using the same figure to obtain ()/y N Mand()/MM used to obtain ()/x N T P and ()/x M P .It follows that:yN T ⎛⎞=⎝⎠(15) 26yM T ⎛⎞=⎝⎠ (16) 26y yy nbN M K K T Tσ=± (17)The Welding Research Council, Inc.WRC 53716Local Stresses in Spherical and Cylindrical Shells Due To External Loading3.3.3Stresses Resulting From Torsional Moment, T MIn the case of a round attachment (such as a pipe), torsional moment is assumed to induce pure shear stresses, so that shear stress ()τ in the shell at the attachment-to-shell juncture is given by:202Tyx xy M r Tττπ==(18) If only shear stresses are being considered, it is to be noted that the equivalent stress intensity is twice the above calculated shear stress.In the case of rectangular attachments, torsional moment produces a complex stress field in the shell. Acceptable methods of analyzing this situation are not available at this time. If the designer has reason for concern, the problem should be resolved by testing in accordance with established code procedures. 3.3.4 Stresses Resulting From Shear Load, V Bijlaard has proposed 14 that shear force()V can be assumed transmitted to the shell entirely bymembrane shear force. Therefore, stresses in the shell at the attachment-to-shell juncture can be approximated as follows:3.3.4.1 Round Attachment0sin xy V(refer to Figure 1)r T τθπ=(19)3.3.4.2 Square Attachment1(90270)4xy V at and c Tτθ==°° (20)3.3.5 Stresses Resulting From Arbitrary LoadingIn the general case, all applied loads and moments must be resolved (at the attachment-shell interface) in the three principal directions; i.e., they must be resolved into components 1212,,,,,T P V V M M and M . If one then proceeds in the manner previously outlined, membrane, bending and shear stresses can be evaluated at eight distinct points in the shell at its juncture with the attachment. These eight points are shown in the sign convention chart, Table 1.The numerous stress components can be readily accounted for, if a scheme similar to that shown in Table 2 and 3 is adopted. In using this scheme, it is to be noted that the Maximum Shear Theory has been used to determine equivalent stress intensities. Also, it is to be noted that evaluation of stresses resulting from internal pressure has been omitted.Test work conducted by PVRC has shown that stresses attenuate rapidly at points removed from the attachment-to-shell juncture, the maximum stress frequently being located at the juncture.* However, in the general case of arbitrary loading, one has no assurance that the absolute maximum stress intensity in the shell will be located at one of the eight points considered in the above discussion.3.4 List Of Nondimensional Curves For Spherical ShellsThe nondimensional curves for solid and hollow attachments in spherical shells is shown on page 43 .*Under certain conditions stresses may be higher in the nozzle wall than they are in the vessel wall. This possibility is most likely if the nozzle opening in not reinforced or if the reinforcement is placed on the vessel wall and not on the nozzle.The Welding Research Council, Inc.WRC 537Local Stresses in Spherical and Cylindrical Shells Due To External Loading254.3.5.2 Rectangular Attachment14cx V c Tφτ=(50) 24Lx V c Tφτ=(51) 4.3.6 Stresses Resulting From Arbitrary LoadingIn the general case, all applied loads and moments must be resolved (at the attachment-to-shell interface) in the three principal directions; i.e., they must be resolved into components ,,,,,c L c L T P V V M M and M . If one then proceeds in the manner previously outlined (e.g., paragraph 4.3.1.1), membrane, bending and shear stresses can be evaluated at eight points in the shell at its juncture with the attachment. These eight points are shown in the sign convention chart, Table 4.4.4 Nondimensional Curves For Cylindrical ShellsThe nondimensional curves which follow constitute, in general, a replot of Bijlaard's data to a semilog scale in order that certain portions of the curves can be read with greater facility. Those portions of the curves which are taken directly from Bijlaard's work are shown as solid curves; those portions of the curves which have been modified on the basis of recent experimental data, as discussed in Appendix A, are shown as dotted curves.In the case of longitudinal moment loading and axial loading (thrust), two sets of curves are shown for the bending components of stress-one set applying to the longitudinal axis, and the other applying to an area of maximum stress off the axes of symmetry (longitudinal moment), or to the transverse axis (thrust). In the latter case, a portion of the original curves has been deleted in order to emphasize that the curves should not be used beyond the limits indicated. This was done because the available data indicated that the "outer limits" of the curves were appreciably unconservative, with no feasible manner to "correct" them (as explained in Appendix A).In the case of longitudinal moment , the exact location, of the maximum stress cannot be defined with certainty, but Figure A-14 will provide an estimate of its location (considering that the location of maximum stress under internal pressure and longitudinal moment was essentially the same on IIT model "C-1," as shown on Figures A-2 and A-3). It should also be noted that, to the best of our knowledge, the curves for "maximum stresses off the axes of symmetry" (Figures 1B-1 and 2B-1) would apply only to the case of a round, flexible nozzle connection; it is conceivable that a similar effect might apply to a rigid square or rectangular attachment, for which the shell at the outer edges of the attachment might take a greater part of the load than that portion of the shell adjacent to the longitudinal centerline. However, we know of no direct evidence to support such an assumption.4.4.1 List Of Nondimensional Curves For Cylindrical ShellsThe list of nondimensional curves for cylindrical shells is shown on page 91.4.5 Limits On ApplicationWhere relatively large attachments are considered, or when situations are encountered that deviate considerably from the idealized cases presented herein, the designer should refer to paragraph A.3 in Appendix A and to the original references to ascertain the limitations of applicability for the procedure used. However, there are a few generalizations that can safely be made regarding vessel and attachment geometry.The Welding Research Council, Inc.WRC 53726Local Stresses in Spherical and Cylindrical Shells Due To External Loading4.5.1 External Radial LoadStresses are affected very little by the ratio of shell length to shell radius ()/m l R . Therefore, no restriction is made on the point of load application except in very extreme cases. The curves included in this report are for an /m l R ratio of 8, which is sufficient for most practical applications. On the basis of data presented in Bibliographical Reference 2, results based on an /m l R ratio of 8 will be slightly conservative for lesser values of /m l R ratio and unconservative for greater values of /m l R ratio. However, the error involved does not exceed approximately 10% of all /m l R values greater than 3, which should be sufficiently accurate for most calculations. Since for lesser values of /m l R , the results are conservative, no restriction will ordinarily be necessary on /m l R ratio or the point of load application. For extreme cases or for "off center" loading, one may make corrections by use of the curves presented on page 8 of Bibliographical Reference 2, if desired.Results are not considered applicable in cases where the length of the cylinder ()l is less than its radius()m R . This applies either to the case of an open ended cylinder or closed ended cylinder where thestiffness is appreciably modified from the case considered.4.5.2 External MomentResults are applicable in the case of longitudinally off center attachments (a more usual case) provided that the attachment is located at least half the shell radius ()0.5m R from the end of the cylinder.4.5.3 Attachment StressesThe foregoing procedure provides one with a tool to find stresses in the shell, but not in the attachment. Under certain conditions, stresses may be higher in the attachment than they are in the vessel. For example, in the case of a nozzle, it is likely that the stresses will be higher in the nozzle wall than they are in the vessel wall if the nozzle opening is unreinforced or if the reinforcement is placed on the vessel wall and not on the nozzle.5 ACKNOWLEDGMENTThe authors wish to acknowledge the significant contributions made by J. B. Mahoney of Applied Technology Associates Inc. and M. G. Dhawan of the Bureau of Ships during the preparation of this paper. In addition, the comments received during the review of this document by the members of the PVRC Subcommittee on Reinforced Openings and External Loadings are deeply appreciated.6 REFERENCES1. Bijlaard, P. P., "Stresses from local Loadings in Cylindrical Pressure Vessels," Trans. A.S.M.E., 77,805-816 (1955).2. Bijlaard, P. P., "Stresses from Radial Loads in Cylindrical Pressure Vessels," Welding Jnl., 33 (12),Research Supplement, 615-s to 623-s (1954).3. Bijlaard, P. P., "Stresses from Radial Loads and External Moments in Cylindrical Pressure Vessel,"Ibid., 34 (12). Research Supplement, 608-s to 617-s (1955).4. Bijlaard, P. P., "Computation of the Stresses from Local Loads in Spherical Pressure Vessels orPressure Vessel Heads," Welding Research Council Bulletin No. 34, (March 1957).5. Bijlaard, P. P., "Local Stresses in Spherical Shells from Radial or Moment Loadings," Welding Jnl., 36(5), Research Supplement, 240-s to 243-s (1957).6. Bijlaard, P. P., "Stresses in a Spherical Vessel from Radial Loads Acting on a Pipe," Welding ResearchCouncil Bulletin No. 49, 1-30 (April 1959).7. Bijlaard, P. P., "Stresses in a Spherical Vessel from External Moments Acting on a Pipe," Ibid., No. 49,31-62 (April 1959).The Welding Research Council, Inc.Table 5 Continued – Computation Sheet for Local Stresses in Cylindrical ShellsWRC 537Local Stresses in Spherical and Cylindrical Shells Due To External Loading 39The Welding Research Council, Inc.WRC 53740Local Stresses in Spherical and Cylindrical Shells Due To External LoadingTable 6 – Radial Load PTable 7 – Circumferential Moment c M12/ββγc K for θ c K for M φc xK for M c C for N φ c x C for N0.2515 1.09 1.31 1.84 0.31 0.4950 1.04 1.24 1.62 0.21 0.46 100 0.97 1.16 1.45 0.15 0.44 300 0.92 1.02 1.17 0.09 0.46 0.515 1.00 1.09 1.36 0.64 0.7550 0.98 1.08 1.31 0.57 0.75 100 0.94 1.04 1.26 0.51 0.76 300 0.95 0.99 1.13 0.39 0.77 215 (1.00) (1.20) (0.97) (1.7) (1.3)100 1.19 1.10 0.95 1.43 1.12 300 --- (1.00) (0.90) (1.3) (1.00) 415 (1.00) (1.47) (1.08) (1.75) (1.31)100 1.49 1.38 1.06 1.49 0.81 300 --- (1.27) (0.98) (1.36) (0.74)Note: The values in parenthesis determined by an approximate solution.C u r v e F i t C o e f f i c i e n t s f o r F i g u r e S P -1The Welding Research Council Inc.F i g u r e S P - 2 S t r e s s e s i n S p h e r i c a l S h e l l D u e t o a R a d i a l L o a d P o n N o z z l e C o n n e c t i o n0.01N xN yx (M A X )y (MA X )The Welding Research Council Inc.C u r v e F i t C o e f f i c i e n t s f o r F i g u r e S P -2The Welding Research Council Inc.F i g u r e S P -3 – S t r e s s e s i n S p h e r i c a l S h e l l D u e t o a R a d i a l L o a d P o n N o z z l e C o n n e c t i o nThe Welding Research Council Inc.C u r v e F i t C o e f f i c i e n t s f o r F i g u r e S P -3The Welding Research Council Inc.F i g u r e S P -4 – S t r e s s e s i n S p h e r i c a l S h e l l D u e t o a R a d i a l L o a d P o n N o z z l e C o n n e c t i o n0.01N xN yM x(M A X )The Welding Research Council Inc.C u r v e F i t C o e f f i c i e n t s f o r F i g u r e S M -2The Welding Research Council Inc.F i g u r eS M-3 – S t r e s s e s i n S p h e r i c a l S h e l l D u e t o O v e r t u r n i n g M o m e n tM o n a N o z z l e C o n n e c t i o nThe Welding Research Council Inc.r R TC u r v e F i t C o e f f i c i e n t s f o r F i g u r e S M -3The Welding Research Council Inc.F i g u r eS M-4 – S t r e s s e s i n S p h e r i c a l S h e l l D u e t o O v e r t u r n i n g M o m e n tM o n a N o z z l e C o n n e c t i o n0.010.10.1N xM yN y (M A X )M x (MA X )The Welding Research Council Inc.C u r v e F i t C o e f f i c i e n t s f o r F i g u r e S M -8The Welding Research Council Inc.F i g u r eS M-9 – S t r e s s e s i n S p h e r i c a l S h e l l D u e t o O v e r t u r n i n g M o m e n tM o n a N o z z l e C o n n e c t i o nThe Welding Research Council Inc.r R TC u r v e F i t C o e f f i c i e n t s f o r F i g u r e S M -10The Welding Research Council Inc.The Welding Research Council, Inc.THIS PAGE INTENTIONALLY LEFT BLANKC u r v e F i t C o e f f i c i e n t s f o r F i g u r e 3A – E x t r a p o l a t e dThe Welding Research Council Inc.F i g u r e 4A – M o m e n t()2/cmN MR φβ D u e t o a n E x t e r n a l C i r c u m f e r e n t i a l M o m e n t c M on a C i r c u l a r C y l i n d e r – O r i g i n a lThe Welding Research Council Inc.βC u r v e F i t C o e f f i c i e n t s f o r F i g u r e 4A – O r i g i n a lThe Welding Research Council Inc.i g u r e 1B – M o m e n t()/L m M M R φβ D u e t o a n E x t e r n a l L o n g i t u d i n a l M o m e n t LMo n a C i r c u l a r C y l i n d e r (S t r e s s o n t h e L o n g i t u d i n a l P l a n e o fS y m m e t r y ) – O r i g i n a lβThe Welding Research Council Inc.C u r v e F i t C o e f f i c i e n t s f o r F i g u r e 2B -1 – E x t r a p o l a t e dThe Welding Research Council Inc.F i g u r e 3B – M e m b r a n e F o r c e()2/LmN MR φβ D u e t o a n E x t e r n a l L o n g i t u d i n a l M o m en t LMo n a C i r c u l a r C y l i n d e r – O r i g i n a lβThe Welding Research Council Inc.C u r v e F i t C o e f f i c i e n t s f o r F i g u r e 1C – E x t r a p o l a t e dWRC Bulletin 537Local Stresses in Spherical and Cylindrical Shells Due To External Loading127The Welding Research Council Inc.F i g u r e 1C -1 – B e n d i n g M o m e n tx M PD u e t o a nE x t e r n a l R a d i a l L o a d P o n a C i r c u l a r C y l i n d e r (L o n g i t u d i n a l A x i s ) – O r i g i n a l WRC Bulletin 537128Local Stresses in Spherical and Cylindrical Shells Due To External LoadingThe Welding Research Council Inc.C u r v e F i t C o e f f i c i e n t s f o r F i g u r e 1C -1 – O r i g i n a lWRC Bulletin 537Local Stresses in Spherical and Cylindrical Shells Due To External Loading129The Welding Research Council Inc.F i g u r e 1C -1 – B e n d i n g M o m e n tx M PD u e t o a nE x t e r n a l R a d i a l L o a d P o n a C i r c u l a r C y l i n d e r (L o n g i t u d i n a l A x i s ) – E x t r a p o l a t e d 0.10.5WRC Bulletin 537130Local Stresses in Spherical and Cylindrical Shells Due To External LoadingThe Welding Research Council Inc.C u r v e F i t C o e f f i c i e n t s f o r F i g u r e 1C -1 – E x t r a p o l a t e dWRC Bulletin 537Local Stresses in Spherical and Cylindrical Shells Due To External Loading131The Welding Research Council Inc.F i g u r e 2C – B e n d i n g M o m e n tx M PD u e t o a nE x t e r n a l R a d i a l L o a d P o n a C i r c u l ar C y l i n d e r (T r a n s v e r s e A x i s ) – O r i g i n a l WRC Bulletin 537132Local Stresses in Spherical and Cylindrical Shells Due To External LoadingThe Welding Research Council Inc.The Welding Research Council, Inc.WRC 537Local Stresses in Spherical and Cylindrical Shells Due To External Loading183B.6 FiguresFigure B-1 – Stepped BarThe Welding Research Council, Inc.WRC 537184Local Stresses in Spherical and Cylindrical Shells Due To External Loading00.050.100.150.200.250.300.35Scale BScale A0.51.01.52.02.53.03.5S t r e s s C o n c e n t r a t i o n F a c t o r , KRatio of Fillet Radius to Shellor Nozzle Thickness (r/T, 2r/d n , or 2r/h)5.04.03.02.01.51.0Figure B-2 – Stress Concentration Factors for D d >>。
改进蝴蝶算法优化支持向量机的土壤含水量预测模型
改进蝴蝶算法优化支持向量机的土壤含水量预测模型
王仲英;刘秋菊
【期刊名称】《计算机工程与设计》
【年(卷),期】2023(44)2
【摘要】针对传统土壤含水量预测方法精度低、效率差的不足,提出改进蝴蝶算法优化支持向量机的土壤含水量预测算法。
引入Levy飞行改进蝴蝶优化算法的位置更新方式,结合高频短步长跳跃搜索和低频长步长行走策略,同步实现局部精细搜索和远程区域勘探,提升寻优能力;设计基于高斯变异和混沌Logistic映射的个体扰动机制,提升种群多样性。
利用改进蝴蝶优化算法LGBOA优化SVM模型,构建土壤含水量预测模型。
选取某地土壤气象数据为样本进行实验分析,验证LGBOA-SVM 模型可以提高土壤含水量预测精度和效率。
【总页数】10页(P612-621)
【作者】王仲英;刘秋菊
【作者单位】河南省智慧农业远程环境监测控制工程技术研究中心应用技术研究院;郑州工程技术学院信息工程学院
【正文语种】中文
【中图分类】TP183
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应用地球化学元素丰度数据手册-原版
应用地球化学元素丰度数据手册迟清华鄢明才编著地质出版社·北京·1内容提要本书汇编了国内外不同研究者提出的火成岩、沉积岩、变质岩、土壤、水系沉积物、泛滥平原沉积物、浅海沉积物和大陆地壳的化学组成与元素丰度，同时列出了勘查地球化学和环境地球化学研究中常用的中国主要地球化学标准物质的标准值，所提供内容均为地球化学工作者所必须了解的各种重要地质介质的地球化学基础数据。
本书供从事地球化学、岩石学、勘查地球化学、生态环境与农业地球化学、地质样品分析测试、矿产勘查、基础地质等领域的研究者阅读，也可供地球科学其它领域的研究者使用。
图书在版编目（CIP）数据应用地球化学元素丰度数据手册/迟清华，鄢明才编著. －北京：地质出版社，2007.12ISBN 978－7－116－05536－0Ⅰ. 应… Ⅱ. ①迟…②鄢…Ⅲ. 地球化学丰度－化学元素－数据－手册Ⅳ. P595－62中国版本图书馆CIP数据核字（2007）第185917号责任编辑：王永奉陈军中责任校对：李玫出版发行：地质出版社社址邮编：北京市海淀区学院路31号，100083电话：（010）82324508（邮购部）网址：电子邮箱：zbs@传真：（010）82310759印刷：北京地大彩印厂开本：889mm×1194mm 1/16印张：10.25字数：260千字印数：1－3000册版次：2007年12月北京第1版•第1次印刷定价：28.00元书号：ISBN 978－7－116－05536－0（如对本书有建议或意见，敬请致电本社；如本社有印装问题，本社负责调换）2关于应用地球化学元素丰度数据手册（代序）地球化学元素丰度数据，即地壳五个圈内多种元素在各种介质、各种尺度内含量的统计数据。
它是应用地球化学研究解决资源与环境问题上重要的资料。
将这些数据资料汇编在一起将使研究人员节省不少查找文献的劳动与时间。
这本小册子就是按照这样的想法编汇的。
壳体局部应力校核方法
（４）吊耳下部Ｂ点处壳体内、外表面所受的周
向应力：
曰点内表面：Ｏｒ娲＝Ｎ十／８—６Ｍ十／８２
（１３）
Ｂ点外表面：盯幽，＝Ｎ十／８＋６Ｍ十／８２
（１４）
（５）吊耳下部Ｂ点处壳体内、外ｘ／６２
（１５）
Ｂ点外表面：％。，＝暇／８＋６ＭＪ８２
（１６）
（６）吊耳下部Ｂ点处壳体中面所受的周向、轴
４）因ｏｒ。是由外载荷引起的局部薄膜应力，许 用值取１．５［ｏｒ］。。综上所述：
ｏｒ。＜３［盯］ｓ，盯ｉ＜１．５［ｏｒ］ｓ，盯ｋ＜１．５［／９＂］ｓ（２０） 只要式（２０）满足，吊耳处壳体局部应力合格。
３结语 综上所述，通过对轴式吊耳在就位这种危险
工况下吊耳、壳体受力状态的分析，总结出轴式吊 耳强度校核及吊点处壳体局部应力的计算方法。
轴式吊耳受力分析见图２。应对管轴的危险 截面、焊缝截面进行弯曲、拉伸及剪切应力校核。
轴式吊耳与设备或衬板的连接处，常焊有加强筋 板，为简化计算并偏于安全，计算时不予计人。
万方数据
图２直立状态时轴式吊耳受力分析 １．１．１校核轴式吊耳危险截面应力
管轴与衬板连接端面为危险截面。
收稿日期：２００９～０４—２４。 作者简介：王贵丁，男，福建泉州市人，２００２年毕业于 北京化工大学化工设备与机械专业，获工学学士学 位，工程师，从事石油化工设备的设计工作。联系电 话：０１０—８４８７８５１７
根据Ｒ。∞、ｙ及肘。，可算得Ｍｉ、Ⅳｆ（ｉ＝ｘ，咖）。 根据标准ＨＧ２０５８２－－１９９８表２６—４可以求得 图４所示各个位置的应力。其中Ａ。、Ｂ。、ＧＵ、Ｄ。分 别为点Ａ、曰、ｃ、Ｄ处壳体外表面；ＡＬ、ＢＬ、ｃＬ、Ｄ。分 别为点Ａ、曰、Ｇ、Ｄ处壳体内表面；Ａｍ、Ｂｍ、ｃｍ、Ｄ。分 别为点Ａ、Ｂ、ｃ、Ｄ处壳体中面；根据表２６—４可 知：点Ａ、日处壳体不存在由Ｋ引起的剪切应力； 点Ｃ、Ｄ处壳体不存在由Ｍ。＋引起的周向和轴向应 力。同时，点Ａ与点曰处壳体周向和轴向应力大 小相等，方向相反；点ｃ与点Ｄ处壳体剪切应力大 小相等，方向相反；因此只需校核点Ｂ、点Ｄ处壳 体应力即可。
Effect of low temperature thermo-mechanical treatment on microstructure and mechanical properties
J. Cent. South Univ. Technol. (2010) 17: 443−448DOI: 10.1007/s11771−010−0504−6Effect of low temperature thermo-mechanical treatment onmicrostructures and mechanical properties of TC4 alloySUN Li-ping(孙利平)1, LIN Gao-yong(林高用)1,2, LIU Jian(刘健)1, ZENG Ju-hua(曾菊花)11. School of Materials Science and Engineering, Central South University, Changsha 410083, China;2. Key Laboratory of Nonferrous Metal Materials Science and Engineering, Ministry of Education,Central South University, Changsha 410083, China© Central South University Press and Springer-Verlag Berlin Heidelberg 2010Abstract: The effects of low temperature thermo-mechanical treatment (LTTMT) on microstructures and mechanical properties of Ti-6Al-4V (TC4) alloy were studied by optical microscopy (OM), tensile test, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The experimental results confirm that the strength of TC4 alloy can be improved obviously by LTTMT processing, which combines strain strengthening with aging strengthening. The effect of LTTMT on the alloy depends on the microstructure of the refined and dispersed α+β phase on the basis of high dislocation density by pre-deformation below recrystallization temperature. The tensile strength decreases with the increase of pre-deformation reduction. The optimal processing parameters of LTTMT for TC4 alloy are as follows: solution treatment at 900 ℃ for 15 min, pre-deformation in the range of 600−700 ℃ with a reduction of 35%, finally aging at 540 ℃ for 4 h followed by air-cooling.Key words: Ti-6Al-4V (TC4) alloy; low temperature thermo-mechanical treatment; microstructure; mechanical properties; strain strengthening1 IntroductionTC4 alloy is one of the typical (α+β) Ti alloys. Since Ti-6Al-4V was first applied in 1954, it has become the most important Ti alloy and has been widely used around the world nowadays, for the products of TC4 alloy account for about 60% of all Ti output [1]. Although the alloy has been used for a number of years, researches on this alloy still attract much attention of researchers from both fundamental and practical point of view, such as superplastic forming and diffusion bonding (SPF/DB) technology [2−3], numerical simulation on forging process [4], stress relaxation behavior [5], surface engineering technologies [6−8], constitutive relationship [9−10], fatigue crack growth behavior [11−12], hydrogen treatment [13], and high temperature thermo-mechanical treatment (HTTMT) technology [14]. However, the study of low temperature thermo- mechanical treatment (LTTMT) on TC4 alloy has not been performed, which may be an effective way for strengthening this alloy. In this work, the influences of LTTMT on microstructures and mechanical properties of TC4 alloy were investigated, aiming to find a more effective technology for improving the properties of this alloy.2 ExperimentalThe testing materials used were 1.7 mm-thick hot-rolled TC4 sheets. The finish hot-rolling temperature was 900 ℃. The process flow of LTTMT is illustrated in Fig.1, which includes three stages as follows: solution treatment and quenching, pre-deformation, and aging. The processing parameters of LTTMT were set as follows: solution treatment at 900 ℃ for 15 min, followed by quenching in room-temperature water; pre-deformation in the range of 600−700 ℃, with the pre-deformation reductions of 35%, 50%, and 55%, respectively; aging treatment at 540 ℃ in air for 4 h followed by air-cooling. Besides, the artificial aging before pre-deformation was conducted at 540 ℃ for 2 h, and the natural aging was carried out at the room temperature for 6 d. For the sake of comparing the mechanical property and microstructure at every stage of LTTMT, serial routes are set and shown in Table 1.The microstructure observation was performed using POLYV AR−METⅡ metallographic microscope. Specimens for optical microscopy (OM) were etched bya solution of nitric acid (30 mL)+hydrofluoric acid(20 mL)+H2O (50 mL). Tensile tests were performed on aFoundation item: Project(2008WK2005) supported by the Science and Technology Plan of Hunan Province, ChinaReceived date: 2009−06−25; Accepted date: 2009−08−29Corresponding author: LIN Gao-yong, PhD, Professor; Tel: +86−731−88830266; Fax: +86−731−88876692; E-mail: mater218@Fig.1 Schematic illustration of LTTMT: 1—Heating; 2—Solution treatment; 3—Water cooling; 4—Pre-deformation; 5—Aging; Tβ—Transition temperature of β phase; T r—Temperature of recrystallizationTable 1 Routes of different samplesSample No. Route Processflow1 H Hot-rollingstate 2 S Solutiontreatment 3 SA Solutiontreatment→Artificial aging4 SD1ASolution treatment→Pre-deformation(35%)→Artificial aging5 SD2ASolution treatment→Pre-deformation(50%)→Artificial aging6 SD3ASolution treatment→Pre-deformation(55%)→Artificial aging7 SAD2ASolution treatment→Artificial aging→Pre-deformation(50%)→Artificial aging8 SND2ASolution treatment→Natural aging→Pre-deformation(50%)→Artificial aging9 SD0Solution treatment→Room temperature pre-deformation(40%)CSS−44100 universal electronic tensile test machine. Additionally, the fracture cross-sections of TC4 samples by tensile test were analyzed by scanning electron microscopy (SEM), using KYKY−Amray 2800 in this work. The TEM investigations were carried out on an H−800 transmission electron microscope to observe the sub-structure in TC4 alloy at different stages of the LTTMT.3 Results and discussion3.1 Mechanical propertiesThe measuring values of mechanical properties (tensile strength σb, yield strength σ0.2, and elongation δ) of TC4 alloy processed by LTTMT and other comparing routes are obtained and compiled in Table 2.Comparing mechanical properties of TC4 alloy prepared by SA, SD1A, SD2A and SD3A routes, it is evident that the strength and the plasticity of TC4 alloy Table 2 Mechanical properties of TC4 alloy after treated by LTTMT and other routesSample No.Route σb/MPa σ0.2/MPa δ/%1 H 883.82835.487.622 S 890.14802.907.183 SA 942.34851.91 2.634 SD1A 1 165.64 1 091.94 3.005 SD2A 1076.29 946.55 3.606 SD3 A 1 022.40 938.78 4.007 SAD2A 1 072.76 1 024.93 4.208 SND2A896.08 816.59 4.209 SD0 748.78 666.27 1.00can be improved obviously by LTTMT processing. Pre-deformation reduction influences mechanical properties of TC4 alloy acutely. The tensile strength decreases with the increase of pre-deformation reduction, which is opposite to the variation of HTTMT [14]. And itis remarkable that the plasticity of TC4 alloy rises slightly with the increase of pre-deformation reduction from 35% to 55% in the process of LTTMT.Comparing σb of SAD2A and SD2A routes, it can be found that there is little difference for σb (1 072.76 MPa and 1 076.29 MPa, respectively) of the two routes, indicating that the artificial aging before pre-deformationis not necessary. The tensile strength of TC4 alloy processed by SAD2A route differs a lot from that by SND2A route, which indicates that strengthening effectby artificial aging before pre-deformation is stronger than that by natural aging. Besides, the elongations of these two routes are the same (4.20%), indicating that the effects of natural aging and artificial aging before pre-deformation on plasticity of this alloy may be the same when the pre-deformation reductions are both 50%.The lowest tensile strength σb (748.78 MPa) and the lowest elongation δ (1.00%) occur in the route of SD0. Itis evident that room-temperature rolling after solution treatment is not an effective way for improving the properties of TC4 alloy. From the data in Table 2, it can also be noticed that the value of σb is close to the value ofσ0.2 in every route, i.e., the yield ratio (σ0.2/σb) is high, which may result in difficulty in cold-deformation.3.2 Microstructural evolutionFig.2 shows the optical micrographs of hot-rolled, solution treated and aged TC4 alloy.As shown in Fig.2(a), the microstructure of TC4 alloy after hot-rolling is mainly equiaxed structure withthe prior α phase and transformed β phase. During hot- rolling carried out at 900℃, above the recrystallization temperature (T r), the recrystallization and deformation occur simultaneously. In the sequent air-cooling, β phaseFig.2 Optical micrographs of TC4 alloy by different procedures: (a) Hot rolling; (b) Solution treatment; (c) Solution treatment+ agingwill transform to secondary α phase, which nucleates in βgrains or the grain boundary of prior α phase [1].The microstructure of TC4 alloy upon solution treatment followed by water-quenching is shown in Fig.2(b). From the image, it can be found that the high cooling rate after solution treatment in α+β phase field results in martensite transformation, for acicular α′ phase can be recognized in Fig.2(b). Besides, it can also be found that there exist small amounts of prior α phase and untransformed β phase. Because the martensite in Ti alloy cannot improve the strength as the martensite does in steel, the strengthening efficiency in TC4 alloy is low [1], resulting in that the strength of state S is a little higher than that of state H shown in Table 2.The microstructure of specimen after solution treatment and aging at 540 ℃ for 4 h is shown in Fig.2(c). It can be seen from Fig.2(c) that the microstructure of TC4 alloy is mainly composed of the modified and dispersed α+β phase indicating that artificial aging following solution treatment is a good way to improve the mechanical properties of TC4 alloyas shown in Table 2. In the process of decomposition of α′ phase, α phase, which has a hexagonal lattice with the parameter comparable with α′ phase, may precipitate first, along with the increase of the β-stabilized element content, resulting in that the rest meta-stable phase is reconstructed into β crystal lattice, shown as follows: α′→α′+α→α+β.TEM image of the specimen after solution treatment and pre-deformation (Fig.3(a)) shows the microstructure modified by pre-deformation. This reveals that the grain boundary regions have higher defect density than the grain interior due to the dislocation accumulation alongthe grain boundaries during rolling. It may also be seenin this image that the grains contain the substructure. Asthe density of dislocation increases, the dislocations will pile up in localized areas and tangle with each other, leading to the inhomogenous distribution. Based on the increase of dislocations and their motion, cellular structure will occur in the grains. It is known that the density inside the cellular structure is much lower than that near the cellular wall. The substructure in grains makes the strength of TC4 alloy slightly increased.Fig.3 TEM images of TC4 alloy by different procedures: (a) Solution treatment+pre-deformation (35%); (b) Solution treatment+pre-deformation (35%)+agingOn the basis of the pre-deformation, the aging was carried out in order to modify the microstructure and consequently improve the mechanical properties. It is shown in Fig.3(b) that after aging treatment the structureis relatively regular, and the density of dislocation decreases in the heating process. According to the formerobservation (Fig.3(a)), the dislocations accumulate and tangle with each other, leading to the distortion energy storing in the material, which should be released during heating. Meanwhile, the decomposition of meta-stable phase will occur under the influence of the normalization of sub-grains. Being different from the aging without pre-deformation, the decomposition and the dislocation reaction influence each other in this alloy, which leads to the aging strengthening and the strain strengthening.As shown in Fig.4, the microstructures of TC4 alloy by procedures of SD1A, SD2A and SD3A are mainly refined and dispersed α+β phases. Comparing the micrographs in Figs.4(a) and (b), it can be found that the size of α particles (light phase) increases with the increase of pre-deformation reduction. Additionally, the particles are in the similar size when the pre-deformation reduction is in a small discrepancy, shown in Figs.4(b) and (c). Comparing the microstructures of SA, SD1A, SD2A and SD3A routes, it is evident that the particles of TC4 alloy become smaller and more dispersive byFig.4 Optical micrographs of TC4 alloy by different procedures: (a) Solution treatment+pre-deformation(35%)+aging; (b) Solution treatment+pre-deformation(50%)+aging; (c) Solution treatment+pre-deformation(55%)+aging LTTMT technology.In general, the strength will be enhanced with the increase of pre-deformation reduction, which can be proved in the study of HTTMT on TC4 alloy. However, the inverse law is obtained in this work that the tensile strength decreases with the increase of pre-deformation reduction.There may be two mechanisms for the explanation to this phenomenon. One possible mechanism may be that during the pre-deformation before artificial aging, the density of dislocation in the alloy increases with the increase of pre-deformation reduction, leading to the serious distortion of crystal lattice. On the other hand, the distortion of crystal lattice is a form of inner energy in the alloy. Thus, the inner distortion energy increases with the increase of pre-deformation reduction, inducing that the phases decomposed in the aging treatment agglomerate and grow into larger size, which results in the lower efficiency of strengthening. Additionally, the crystal lattices of decomposition phase may be different transitional crystal lattices based on different pre-deformation reductions, which may influence the effect of hardening.Another possible mechanism may be that during the heating of aging treatment, the recovery and polygoniza- tion occur along with the phase transformation, which weakens the effect of strain strengthening provided by pre-deformation. The phases decomposed during the aging will influence the polygonization, and on the other hand, the polygonization will change the density and the diffusion form of the decomposed phases (Fig.3(b)). As the pre-deformation reduction increases, the influence of recovery and polygonization on the diffusion decomposition phases will become greater during aging, which may be one reason for the lower hardening.From the above explanations, it seems that the mechanisms of the pre-deformation reduction on the strength of TC4 alloy during LTTMT should be further studied.From Table 2, it can be noted that the values of elongation (δ) of S and SD1A routes differ a lot (from 7.18% to 3.00%), indicating that the plasticity of TC4 alloy upon LTTMT is lower than that upon solution treatment, which may be identified in Fig.5. Besides, it is suggested that the structure of continuous β phase with diffusive α phase can represent large brittleness, which may be the possible reason for the lower plasticity by LTTMT [15].Comparing the morphologies of dimples in Figs.5(a) and (b), it can be found that the dimples in Fig.5(a) are more uniform and deeper than those in Fig.5(b). Besides, the size of dimples in Fig.5(a) is larger than that in Fig.5(b). Generally, the plasticity will be better when the size of dimples is larger and the rupture condition of theJ. Cent. South Univ. Technol. (2010) 17: 443−448447Fig.5 SEM images of tensile fractures of TC4 alloy by different procedures: (a) Solution treatment; (b) Solution treatment+ pre-deformation(35%)+aging; (c) Higher magnification of Fig.5(a); (d) Higher magnification of Fig.5(b)material is the same. Therefore, the plasticity of TC4 alloy upon LTTMT is lower than that upon solution treatment, consisting with the results in Table 2.According to the observation in Fig.2(b), the structure after solution treatment may primarily contain hexagonal α′ martensite and small amount of prior α phase along the grain boundary. It may be considered that the particles in Fig.5(c) exist in the form of prior α phase, and those in Fig.5(d) exist in the form of diffusion α phase. It can also be observed that there are dimples with different sizes in Fig.5(d). The reason for this phenomenon may depend on the particles with different sizes [16]. The micro-cavities form in the nucleation site of larger particles at first, and then other micro-cavities form in the smaller particles. Finally, different micro-cavities couple with each other, forming dimples with different sizes. In this work, it may be predicted that the phase decomposes from the meta-phase and grows to different sizes.4 Conclusions(1) The strength of TC4 alloy can be improved obviously by the process of LTTMT, which combines the strain strengthening with aging strengthening. And the optimal processing parameters of LTTMT for TC4 alloy are: solution treatment at 900 ℃ for 15 min, pre- deformation in the range of 600−700 ℃ with a reduction of 35%, finally aging at 540 ℃ for 4 h followed byair-cooling.(2) The tensile strength decreases with the increase of pre-deformation reduction, which can be explained by two mechanisms proposed in this work. Besides, the plasticity rises slightly with the increase of pre-deformation reduction.(3) The effect of LTTMT on the alloy depends on the microstructure of refined and dispersed α+β phase on the basis of high dislocation density by pre-deformation below recrystallization temperature.(4) The room temperature deformation is not an effective way to improve the properties of TC4 alloy, for the tensile strength, yield strength and elongation are all the lowest values in all routes.(5) There is little difference between normal LTTMT and complex LTTMT (including pre-artificial or pre-natural aging before pre-deformation), indicating that the aging before pre-deformation may not be needed.References[1]ZHANG Xi-yan, ZHAO Yong-qing, BAI Chen-guang. Titanium alloy and its application [M]. Beijing: Chemical Industry Press, 2005: 287−305. (in Chinese)[2]HAN Wen-bo, ZHANG Kai-feng, WANG Guo-feng. Superplastic forming and diffusion bonding for honeycomb structure of Ti-6Al-4V alloy [J]. Journal of Materials Processing Technology, 2007, 183(2/3): 450−454.[3]LEE H S, YOON J H, CHAN H P, YOUNG G K, DONG H S, LEE C S. A study on diffusion bonding of superplastic Ti-6Al-4V ELI grade [J]. Journal of Materials Processing Technology, 2007, 187/188:J. Cent. South Univ. Technol. (2010) 17: 443−448 448526−529.[4] LU Cheng, ZHANG Li-wen. Numerical simulation on forgingprocess of TC4 alloy mounting parts [J]. Transactions of NonferrousMetals Society of China, 2006, 16(6): 1386−1390.[5] HYUKJAE L, SHANKAR M. Stress relaxation behavior ofshot-peened Ti-6Al-4V under fretting fatigue at elevated temperature[J]. Materials Science and Engineering A, 2004, 366(2): 412−420. [6] LIU Yong, YANG De-zhuang, WU Wan-liang, YANG Shi-qin. Drysliding wear behavior of Ti-6Al-4V alloy in air [J]. Journal of HarbinInstitute of Technology: English Letter, 2002, 9(1): 67−71.[7] LIU Y, YANG D Z, HE S Y, WU W L. Microstructure developed inthe surface layer of Ti-6Al-4V alloy after sliding wear in vacuum [J].Materials Characterization, 2003, 50(4/5): 275−279.[8] BISWAS A, DUTTA M J. Surface characterization and mechanicalproperty evaluation of thermally oxidized Ti-6Al-4V [J]. MaterialsCharacterization, 2009, 60(6): 513−518.[9] NIE Lei, LI Fu-guo, FANG Yong. New constitution relationship forTC4 alloy [J]. Aeronautical Materials Transaction, 2001, 21(3):13−18.(in Chinese)[10] LI L X, PENG D S. Development of constitute equations forTi-6Al-4V alloy under hot-working condition [J]. Acta MetallurgicaSinica: English Letter, 2000, 13(1): 263−269.[11] SHADEMAN S, SOBOVEJO W O. An investigation of short fatiguecrack growth in Ti-6Al-4V with colony microstructures [J].Materials Science and Engineering A, 2002, 335(1/2): 116−127. [12] SINHA V, MERCER C, SOBOYEJO W O. An investigation of shortand long fatigue crack growth behavior of Ti-6Al-4V [J]. MaterialScience and Engineering A, 2000, 287(1): 30−42.[13] LUO Liang-shun, SU Yan-qing, GUO Jing-jie, FU Heng-zhi.Formation of titanium hydride in Ti-6Al-4V alloy [J]. Journal of Alloys and Compounds, 2006, 425(1/2): 140−144.[14] HUANG Hui. Effect of high temperature thermo-mechanicaltreatment (HTTMT) on the structure and properties of TC4 alloy [J].Optic and Precision Engineering, 1996, 4(4): 48−52. (in Chinese) [15] KUBIAK K, SIENIAWSKI J. Development of the microstructureand fatigue strength of two phase titanium alloys in the processes offorging and heat treatment [J]. Journal of Materials Processing Technology, 1998, 78(1/3): 117−121.[16] CUI Niu-xian. Fracture analysis of metals [M]. Harbin: HarbinInstitute of Technology Press, 1998: 34−45. (in Chinese)(Edited by CHEN Wei-ping)。
高速平板边界层中定常条带的前缘感受性
高速平板边界层中定常条带的前缘感受性
刘洋;赵磊
【期刊名称】《空气动力学学报》
【年(卷),期】2024(42)4
【摘要】来流湍流度较高时,自由流涡波可在边界层内激发流向条带结构,并引起边界层的旁路(bypass)转捩。
本文采用调和线性化Navier-Stokes方程(harmonic linearized Navier-Stokes,HLNS)方法模拟平板边界层条带对自由流涡波的前缘感受性,并通过直接数值模拟验证了HLNS方法的可靠性。
针对马赫数4.8的高速平
板边界层,分析了零频涡波激发定常条带的前缘感受性过程及定常条带的演化规律。
研究结果表明,边界层外的自由流涡扰动对边界层条带的发展存在持续的激励作用;
对于固定展向波数的自由流涡波,法向波数为0时激发的条带幅值最大;自由流涡波的法向波数在小于临界角度时仅影响条带的幅值,而不影响条带扰动的形函数剖面。
随着当地雷诺数的增加,条带的幅值演化和形函数剖面呈现出很好的相似性;当地无
量纲展向波数β=0.18时,归一化幅值最大。
【总页数】14页(P14-26)
【作者】刘洋;赵磊
【作者单位】天津大学力学系;天津市现代工程力学重点实验室
【正文语种】中文
【中图分类】V211;V411;O357.4
【相关文献】
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2.前缘曲率变化对平板边界层感受性问题的影响
3.无限薄平板边界层前缘感受性过程的数值研究∗
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因版权原因，仅展示原文概要，查看原文内容请购买。
橡胶树PR107和CATAS8-79中胶乳蛋白的差异分析及磷酸化蛋白的鉴定
橡胶树PR107和CATAS8-79中胶乳蛋白的差异分析及磷酸化蛋白的鉴定作者：王丹徐兵强孙勇彭存智常丽丽仝征来源：《热带作物学报》2022年第05期摘要：橡膠树是合成天然橡胶的重要植物。
PR107和CATAS8-79是具有不同产排胶性状的2个无性系。
在以往的研究中，胶乳中蛋白表达差异被认为是影响天然橡胶合成的关键因子之一。
然而，这2个无性系之间与胶乳产量相关的蛋白质图谱尚未明确。
本研究采用蛋白质组学方法对这些蛋白质进行鉴定，有助于探讨巴西橡胶树胶乳合成机理。
经双向凝胶电泳和质谱鉴定分析，共获得65个差异表达蛋白信息。
通过磷酸化蛋白质组分析，在PR107胶乳中鉴定出31个磷酸化蛋白质，含有74个磷酸化氨基酸残基，在CATAS8-79胶乳中鉴定出80个磷酸化蛋白质，含有166个磷酸化氨基酸残基。
橡胶延伸因子/小橡胶粒子蛋白（REF/SRPP）家族成员被鉴定为差异表达蛋白和磷酸化修饰蛋白，这些蛋白在调节天然橡胶合成中起着重要作用。
pro-hevein和hevamine也表现出不同的磷酸化修饰水平，它们主要在天然橡胶排胶过程中起作用。
一种丝氨酸-苏氨酸蛋白磷酸酶激酶的磷酸化和去磷酸化修饰可能在天然橡胶合成中起调节作用。
这些结果为天然橡胶生物合成调控机制的研究提供了新的理论依据。
关键词：巴西橡胶树;天然橡胶生物合成;磷酸蛋白质组;双向凝胶电泳（2-DE）中图分类号：S794.1文献标识码：AComparative Proteomics Analysis and Identification of Phosphorylated Protein in Latex of Rubber Tree Clones PR107 and CATAS8-79Abstract：Hevea brasiliensis is an important plant for producing natural rubber. RP107 and CATAS8-79 are two clones of H. brasiliensis with different properties of rubber production and expulsion. The study of protein function in the latex may help understand the regulatory mechanism related to the properties of rubber production and expulsion. This study aimed to compare and analyze the difference in latex protein between RP107 and CATAS8-79 at the level of protein accumulation and post-translational modification. Through the two-dimensional gel electrophoresis （2-DE）analysis， 65proteins derived from 88spots were found to be accumulated differently in the latex between the 2 clones. Among the proteins， 44 proteins had high accumulation in the latex of PR107 and 21 had high accumulation in the latex of CATAS8-79. The high-accumulation proteins （HAPs）in the latex of CATAS8-79were involved in intracellular organelles， external encapsulatingstructure， and membrane-bound organelles in terms of cellular component， and most of them had drug-binding activity and hydrolase activity. Different from CATAS8-79， the HAPs in the latex of PR107 participated in a catalytic complex， nonmembrane-bound organelles， and apoplasts. Most of them had protein-binding and transferase activities.Furthermore， some proteins related to natural rubber synthesis and latex agglutination were found in DAPs. The rubber elongation factors（REFs）and small rubber particleproteins （SRPPs）were identified. The two classes of proteins played an important role in natural rubber biosynthesis in rubber trees. Some proteins mediating rubber particle aggregation （RPA） and participating in response to tappingwere found in DAPs too. To determinate the phosphorylated proteins and amino acids in the latex of the two clones， the phosphopeptides were enriched using a Fe-NTA Phosphopeptide Enrichment Kit and shotgun analysis was performed through the high-throughput Tandem Mass Spectrometer （MS/MS）. 74 phosphorylated amino acid residues derived from 31 phosphorylated proteins， as well as 166 phosphorylated amino acid residues derived from 80 phosphorylated proteins， were identified inPR107 and CATAS8-79， respectively. Among the phosphorylated proteins， 25 proteins of PR107 and 74 proteins of CATAS8-79 were specific in terms of the phosphorylation amino acids. Between the two clones， the members of REF/SRPP protein family， which regulate the synthesis of nature rubber （NR） in the latex， have high differentiation capacity at both protein accumulation and phosphorylation modification levels. The pro-hevein and hevamine proteins， which influence the process of rubber expulsion， also showed diversity at the phosphorylation modification level. The phosphorylation and dephosphorylation of an serine/threonine protein phosphatase kinase might play a regulatory role in NR synthesis. The results couldprovide a new theoretical basis for the study of the regulatory mechanism of NR biosynthesis.Keywords：Hevea brasiliensis; natural rubber biosynthesis;phosphoproteome;two-dimensional gel electrophoresis （2-DE）DOI： 10.3969/j.issn.1000-2561.2022.05.004巴西橡胶树（Hevea brasiliensis）是目前最具商业价值的天然橡胶来源[1]。
香港科技大学土工离心机先进模拟技术在岩土工程中的应用_英文_
2
Ng / J Zhejiang Univ-Sci A (Appl Phys & Eng) 2014 15(1):1-21
Ranking
Most significant research
Critical state soil mechanics Small strain and non-linear stiffness Effective behaviour stress of soils triaxial testing
ciples, and principal applications of geotechnical centrifuge modelling are introduced. Modelling of four complex geotechnical problems by the state-ofthe-art geotechnical centrifuge at the Hong Kong University of Science and Technology (HKUST), China is described. The four geotechnical problems are: correction of building tilt, effect of tunnel collapse on an existing tunnel, excavation effect on pile capacity, and liquefied flow and non-liquefied slide of loose fill slopes. New insights from these four types of tests are revealed and the role of state-of-the-art geotechnical centrifuge modelling in improving understanding of the complex geotechnical problems is illustrated. 2 Brief introduction to the development of centrifuge modelling According to Craig (1995), the earliest idea of using a centrifuge to increase self-weight of a small
管道应力分析专业设计统一规定
中国五环
工程有限公司
内蒙古京能锡林煤化有限责任公司基础工程设计0B版
锡林郭勒盟东乌旗褐煤提质项目
11051-PE04-MC-04
第 1 页第16页
管道应力分析
专业设计统一规定
0B 根据审查意见修改费珂阳东升蔡晓峰2014.1
0A 基础工程设计费珂阳东升蔡晓峰2013.10
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4.2.3 弓形效应
对于管道截面上下有温差的管道，需要可虑弓形效应可能产生。
通常对于口径大300mm且容易产生汽化的低温管道必须考虑弓形效应。
4.2.3管道环境温度
管道应力分析的环境温度，应依据建设项目所在地的气象、地质环境及业主的特殊要求来确定。
本项目应力计算的环境温度，对于热管取年最冷月平均温度；对于冷管取年
应力分析
应力分析范围
原则上所有的管道均应考虑应力问题。
应力分析方法
可根据以下具体情况选择采用经验目测、简单公式判断、图表法或详细计算的方法。
介质的危险性(毒性，火灾危险性等)；
管线操作工况（温度，压力，脉动，工作循环强度等）
目测方法。
超高压容器设计实例浅析
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６１． ［７］ 陈泰炜．应用 管 轴 式 吊 耳 时 在 塔 壁 上 附 加 加 强 垫 板 的
计算［Ｊ］．化工施工技术，１９９２ （３）：１８２０，２１．
ＣＨＥＮ Ｔ Ｗ．Ｃａｌｃｕｌａｔｉｏｎ ｏｆｒｅｉｎｆｏｒｃｅｍｅｎｔｐｌａｔｅｄｅ ｓｉｇｎｅｄｆｏｒａｔｏｗｅｒｗａｌｌｗｉｔｈｔｕｂｅｓｈａｆｔｔｙｐｅｌｉｆｔｉｎｇｌｕｇｓ ［Ｊ］．Ｃｈｅｍｉｃａｌｃｏｎｓｔｒｕｃｔｉｏｎｔｅｃｈｎｏｌｏｇｙ，１９９２ （３）：１８ ２０，２１． ［８］ 陈强，宋才华，王 耀 明．塔 式 容 器 用 轴 式 吊 耳 的 校 核 计 算［Ｊ］．化工设备与管道，２００９，４６ （４）：９１２． ＣＨＥＮ Ｑ，ＳＯＮＧ Ｃ Ｈ，ＷＡＮＧ Ｙ Ｍ．Ｃａｌｃｕｌａｔｉｏｎｏｆ ａｘｉａｌｌｉｆｔｉｎｇｌｕｇｆｏｒｖｅｒｔｉｃａｌｖｅｓｓｅｌ［Ｊ］．Ｐｒｏｃｅｓｓｅｑｕｉｐ ｍｅｎｔａｎｄｐｉｐｉｎｇ，２００９，４６ （４）：９１２． ［９］ 夏同伟，朱惠春，苏毅，等．重型设备 耳 式 支 座 设 计［Ｊ］． 化 工 设 备 与 管 道 ，２０１７，５４（６）：１４１７． ＸＩＡ Ｔ Ｗ，ＺＨＵ Ｈ Ｃ，ＳＵ Ｙ，ｅｔａｌ．Ｄｅｓｉｇｎｏｆｌｕｇｓｕｐ
飞机装配中铆接结构静力失效研究进展
Vol. 60 No. 4工程与试验 ENGINEERING & TEST Dec. 2020飞机装配中钏接结构静力失效研究进展赵洪伟(1.中国飞机强度研究所，陕西 西安710065；2.西安交通大学机械工程学院，陕西西安710000)摘要:钾接是目前飞机上应用最为广泛、影响其可靠性和强度的关键问题。
本文对当前的钾接实践和新的钾接静力失效研究进行回顾，以期对产生缺陷的潜在机制有透彻的了解。
本文回顾了传统钾接静强度的现状，找出了导致翎卩接接头静态失效的主要因素；讨论了钾接制造参数和二次弯曲对钾接搭接接头静强度的影响，回顾了处理静态失 效的最新解决方案。
此外,还讨论了钾接技术的新发展，包括不同材料的使用和钾接工艺，并展望了工业钾接的研究和应用前景。
关键词:钾接;静力失效；工艺参数中图分类号:V262.4文献标识码:A doi ：10.3969/j.issn. 1674 -3407.2020.04.002Development of Static Failure of Riveted Structure in Aircraft AssemblingZhao Hongwei 1,2(1. Aircraft Strength Research Institute of China , Xi an 710065 , Shaanxi , China ；2. Department of Mechanical Engineering , Xi'an Jiaotong University , Xi an 710000, Shaanxi , China )Abstract : Riveting is the most widely used in aircraft , which affects its reliability and strength. The purpose of this paper isto make a practical review of current riveting practice and the new riveting static failure research , so as to have a thoroughunderstanding of the potential mechanism of defects. In the paper , the status of traditional riveting static strength isreviewed , and the main factors affecting the static failure of riveted joints are found out. The effects of manufacturing parameters and secondary bending on the static strength of riveted lap joints are discussed , and the latest solutions to static failure are reviewed. In addition , the new development of riveting technology , including the use of different materials andriveting process , is also discussed. Finally , the research and application prospects of industrial riveting are prospected.Keywords ：riveting ； static failure ； processing parameter1引言飞机是一个极其复杂的系统，由各种材料、形状和尺寸的结构组成。
水下运载器声学性能预估
水下运载器声学性能预估傅晓晗 1, 付学志 2, 王敏庆 1*(1. 西北工业大学 航海学院, 陕西 西安, 710072; 2. 中国人民解放军92228部队, 北京, 100072)摘 要: 随着深海捕捞和海洋牧场的发展, 运载器水下辐射噪声对鱼类等海洋生物的影响不可忽视。
为评估水下运载器的辐射噪声对海洋生物的影响, 根据被动声呐方程和水下辐射噪声传播损失特性建立了运载器的安全工作半径计算模型, 量化了水下运载器的安全工作区域。
以商用水下运载器G1和对动力系统进行了声学优化设计的G2为研究对象, 在声学性能试验的基础上分析了2种运载器的声辐射特性, 进一步分别计算、对比了2种运载器与海洋鱼类和水下设备之间的安全工作半径。
研究表明, 运载器的辐射噪声由宽频噪声和线谱噪声组成, 低频线谱噪声是影响运载器声学性能的主要因素, 优化动力系统有效改进了运载器的安全工作半径, 降低了其对海洋生物的影响。
文中工作可为海洋声学牧场的商用运载器声学性能评估及优化提供参考。
关键词: 水下运载器; 水下辐射噪声; 安全工作半径; 海洋声学牧场中图分类号: TJ630.34; U674.76 文献标识码: A 文章编号: 2096-3920(2023)06-0871-07 DOI: 10.11993/j.issn.2096-3920.2022-0094Acoustic Performance Prediction of Undersea VehiclesFU Xiaohan1, FU Xuezhi2, WANG Minqing1*(1. School of Marine Science and Technology, Northwestern Polytechnical University, Xi’an 710072, China; 2. Unit 92228th, the People’s Liberation Army of China, Beijing 100072, China)Abstract: With the development of deep-sea fishing and marine ranching, the impact of undersea radiation noise of vehicles on marine organisms such as fish cannot be ignored . In order to assess the impact of radiation noise from undersea vehicles on marine life, the calculation model of safe working radius for an undersea vehicle was established according to the passive sonar equation and propagation loss characteristics of undersea radiation noise, and the safe working area of undersea vehicles was quantified. Two kinds of commercial undersea vehicles G1 and G2 with acoustic optimization design for the power system were studied. Based on the acoustic performance test, the acoustic radiation characteristics of the two vehicles were analyzed, and the safe working radius between the two undersea vehicles and marine fish as well as undersea equipment were further calculated. The research shows that the radiated noise of the vehicles consists of broadband noise and line spectrum noise, and the line spectrum noise within the low-frequency range is the main factor affecting the acoustic performance of undersea vehicles. The safe working radius of the undersea vehicles is effectively improved by optimizing the power system, thus reducing its impact on marine life. The results of this study provide a reference for the evaluation and optimization of the acoustic performance of commercial vehicles in marine acoustic ranch.Keywords: undersea vehicle; undersea radiation noise; safe working radius; marine acoustic ranching收稿日期: 2022-12-09; 修回日期: 2022-12-18.基金项目: 陕西省自然科学基金资助项目(2021JLM-39).作者简介: 傅晓晗(1995-), 女, 在读博士，主要研究方向为噪声与振动控制.* 通信作者简介: 王敏庆(1970-), 男, 博士, 教授, 主要研究领域为声信息处理与控制.第 31 卷第 6 期水下无人系统学报Vol.31 N o.6 2023 年 12 月JOURNAL OF UNMANNED UNDERSEA SYSTEMS Dec. 2023[引用格式] 傅晓晗, 付学志, 王敏庆. 水下运载器声学性能预估[J]. 水下无人系统学报, 2023, 31(6): 871-877.0 引言随着智慧海洋声学牧场的发展, 环境监测、养殖和运营维保等相关领域对水下运载装备的需求与日俱增[1]。
数字图像相关方法测量芳纶纤维复合材料Ⅰ型裂纹应力强度因子
数字图像相关方法测量芳纶纤维复合材料Ⅰ型裂纹应力强度因子郝文峰;陈新文;邓立伟;王翔;姚学锋【摘要】将数字图像相关方法用于芳纶纤维复合材料单边裂纹在拉伸载荷作用下的断裂问题研究.介绍数字图像相关方法的基本原理,建立数字图像相关方法中位移场与裂纹尖端应力强度因子之间的关系.通过搭建数字图像相关方法光学非接触测量系统,试验表征含单边裂纹芳纶纤维复合材料试验件在拉伸载荷作用下的全场位移.由数字图像相关方法所得位移场提取不同载荷作用下裂纹尖端应力强度因子,并分析最小二乘拟合项数、数字图像相关计算子区域和步长大小对计算结果的影响.结果表明,增加最小二乘拟合项次和合理选择数字图像相关计算子区域和步长大小可以提高应力强度因子计算精度.【期刊名称】《航空材料学报》【年(卷),期】2015(035)002【总页数】6页(P90-95)【关键词】芳纶纤维复合材料;数字图像相关;应力强度因子;裂纹【作者】郝文峰;陈新文;邓立伟;王翔;姚学锋【作者单位】北京航空材料研究院航空材料检测与评价北京市重点实验室,北京100095;北京航空材料研究院航空材料检测与评价北京市重点实验室,北京100095;北京航空材料研究院航空材料检测与评价北京市重点实验室,北京100095;北京航空材料研究院航空材料检测与评价北京市重点实验室,北京100095;清华大学工程力学系,北京100084【正文语种】中文【中图分类】O348.1数字图像相关方法(digital image correlation，DIC)是一种非条纹光测方法，它是现代先进的光电子技术、数字图像处理技术与计算机技术相结合的产物，它直接对物体变形前、后的两幅散斑图像进行相关运算处理，以提取散斑图中所携带的变形信息。
散斑是变形信息的载体，可以通过人工制斑获得或者就直接以试件表面的自然纹理作为标记。
在二维数字图像相关方法的应用方面，国内外都开展了大量的工作。
Corr等［1］利用数字图像相关方法研究了纤维复合材料与混凝土界面的粘接强度，得到较为精确的表面变形场。
WRC107,WRC297,EN13445在筒体上局部应力计算的比较
WRC107，WRC297，EN13445在筒体上局部应力计算的比较一、力学模型和适用范围：1、WRC107：- 筒体上的实心圆柱体、矩形附件和方形附件受外加机械载荷；- 球壳上的接管、实心圆柱体和方形附件受外加机械载荷；- 筒体与圆柱体连接结构的适用直径比d/D ≤ 0.5；- 球壳与接管连接结构的适用直径比d/D ≤0.375；注：准确的说不是0.5而是0.496，见WRC107公报。
这个还有筒体直径和璧厚比值的限制：璧厚和球形封头中径的比值≤ 236；璧厚和筒体中径的比值≤230。
但不知道什么原因软件按中都用的是0.5，或者是我看标准不够认真看错了。
HG20583上球壳与接管连接结构的适用直径比d/D ≤0.5，也应该是0.496而不是0.375见WRC107公报，或许我看错了。
2、WRC297：- 筒体上接管受到外加机械载荷；- 接管与筒体的直径比d/D ≤0.5。
3、EN13445中局部应力计算方法，其适用范围：球壳与接管连接结构: 0.001 ≤ de /R ≤ 0.1；筒体与接管连接结构: 1) 0.001 ≤de /D ≤0.1。
二、壳体上薄膜应力的比较：1、WRC107方法：薄壁管结构或接管壁厚与筒体壁厚相当时，膜应力计算结果偏小；仅当接管壁厚大于筒体壁厚时，计算结果才偏安全；2、WRC297方法：不能得到确定的结论，但得到的膜应力或接近，或大于有限元方法的结果；3、EN13445 方法：将有限元方法得到的膜应力除以1.5倍许用应力后与EN13445方法得到的载荷比相比，EN13445方法的结果其安全裕量总是大于有限元方法的结果。
三、壳体上表面应力：1、WRC107方法：-薄壁管结构，该方法的计算结果偏小；-当接管壁厚与筒体壁厚相当或接管壁厚大于筒体壁厚时，在弯矩作用下，计算结果偏安全；- 在轴向力作用下，计算结果也偏小；2、WRC297方法：该方法的计算结果在绝大多数情况下大于有限元方法的结果；3、EN13445 方法：该方法的结果总是大于有限元方法的结果；在弯矩作用工况下，该方法与有限元方法的结果之比有可能大于2.0。
高耐压高硬度橡胶材料的研究
I
Abstract
Acrylonitrile-butadiene rubber (NBR) has been extensively used as oil resistant sealant due to the polar cyanogen groups on its main chain and its low cost. NBR with high acrylonitrile content is often used to prepare sealing rubber materials with high hardness and pressure resistance, nevertheless, the poor water and cold resistance are obstacles to its applications.
2. Magnesium methyacrylate (MDMA) and zinc methyacrylate (ZDMA) were added and in proportion to a certain amount of carbon black to increase the hardness and pressure resistance. The test of vulcanizing characteristics of the NBR composite and the measurement of mechanical properties and swelling degree of vulcanizate were carried out, and the formulation was also optimized. The measurement of the
基于小尺度网格层析速度反演的孔隙压力预测方法
基于小尺度网格层析速度反演的孔隙压力预测方法
王智瑞
【期刊名称】《工程地球物理学报》
【年(卷),期】2022(19)4
【摘要】深度域层速度场参数是孔隙压力预测方法中最为重要的参数之一,但由于层析成像建模方法受地震资料品质的依赖程度较高,针对复杂构造地层或薄层目标地层,常规层析成像方法的模型建立精度难以得到保障,进而影响孔隙压力预测的精度。
针对上述问题,本文提出一种基于小尺度网格层析成像的速度场建立方法,该方法对泥岩欠压实地层目标域构造进行网格剖分,通过解析共偏移距域道集的剩余曲率为自变量的三维矩阵方程以得到每个剖分网格点的剩余速度校正量,进而利用剩余速度校正量进行模型更新迭代,以提高速度场及孔隙压力预测的精度。
剩余速度场的分辨率及精度由网格步长大小决定,减小网格步长间距能够提高剩余速度场模型建立的精度及分辨率,但会大幅降低建模效率。
运用该方法对泥岩欠压实地层广泛发育的渤海A油田进行了方法测试,由实际资料测试结果分析可知,与常规方法相比,利用小尺度网格层析速度反演方法建立的速度场,能够大幅提高速度场建模的分辨率及精度,进而提高孔隙压力预测的精度,该方法有望在实际生产当中得到广泛的应用。
【总页数】7页(P483-489)
【作者】王智瑞
【作者单位】中海油田服务股份有限公司物探事业部
【正文语种】中文
【中图分类】P631.4
【相关文献】
1.基于高精度速度建模技术的孔隙压力预测方法建立
2.基于特征波属性参数的立体层析速度反演方法研究
3.网格层析速度反演方法在准三维西沙水合物中的应用
4.基于断层正则化的网格层析反演在深度域速度场建模中的应用
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非球面拟合球面的数据处理方法研究与实现
非球面拟合球面的数据处理方法研究与实现
戚向涛;张俊;顾亚平
【期刊名称】《网络新媒体技术》
【年(卷),期】2015(004)001
【摘要】在轮廓仪检测光学元器件利用非球面去拟合球面数据时,采用数据校准的方法生成新的数据.对比轮廓仪的检测数据与该方法生成的数据,结果表明生成的数据与轮廓仪的检测数据一致.本文采取的非球面拟合球面的数据处理方法有效的弥补了轮廓仪生成非球面数据的曲率半径有限的不足,扩展了其曲率半径范围.该方法已经应用到抛光加工中,可以有效的利用生成的数据来指导抛光加工生产,并得到抛光工程师的认可.
【总页数】4页(P54-57)
【作者】戚向涛;张俊;顾亚平
【作者单位】中国科院声学研究所东海研究站上海200032;中国科院声学研究所东海研究站上海200032;中国科院声学研究所东海研究站上海200032
【正文语种】中文
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2.离轴非球面最接近球面半径及非球面度的求解 [J], 王权陡;余景池;张学军;张忠玉
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浅谈运用 WRC107计算圆筒局部应力的技巧
浅谈运用 WRC107计算圆筒局部应力的技巧
杨夫裕;梁新文
【期刊名称】《科技创新与应用》
【年(卷),期】2013(000)027
【摘要】本文论述了运用 WRC107计算时，局部坐标系的定义及优缺点，指出可通过定义圆筒与接管的方向余弦实现整体坐标系向局部坐标系的转化；从理论上分析了外载先叠加再计算对接管根部圆筒上局部应力计算所产生的影响，提出不同工况的外载先叠加后按 WRC107进行计算是偏保守的。
【总页数】1页(P144-144)
【作者】杨夫裕;梁新文
【作者单位】一重集团大连设计研究院有限公司，辽宁大连 116600;一重集团大连设计研究院有限公司，辽宁大连 116600
【正文语种】中文
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