材料力学压杆稳定

1、会计学1材料力学压杆稳定材料力学压杆稳定 maxmax AFN 内燃机、空气压缩机的连杆 crFF crFF crFF 过度对应的压力直线平衡状态不变平衡形式发生变化达到限值小于限值 s变形前的形状、尺寸变形后的形状、尺寸实验确定理论分析计算强度问题强度问题稳定问题稳定问题yBFmmwBxylFcr)(xfw FwxM )(FwxMEIw )( （a)EIFk 202 wkw(b)(b)式的通解为式的通解为)(cossinckxBkxAw （A、B为积分常数为积分常数）mmxyBwFFwxM )(0 00 0 wx,0 0 wLx,0 00 01 10 00 00 00 0 BBABAcoss

2、in0 0 klAsin0 0 A0sin kl0 00 0 wA,.)3 , 2 , 1(0sin nnklkl mxmBxylFw,.)3 , 2 , 1 , 0(2 nnklEIFk ,.)3 , 2 , 1 , 0(222 nlEInF 2 22 2lEIF crmxmBxylFwkxklwsin2sin kllxwsin2 22 2lEIF cr2 22 27 70 0).(crlEIF Fcrl0.3l0.7l22cr)7 . 0 (lEIF C2 22 25 50 0).(crlEIF 2 22 22 2 )(crlEIF lFcr2l22cr)2( lEIF lFcrl/4l/

3、4l/222cr)2/(lEIF l 2 22 2lEIF cr2 22 27 70 0).(crlEIF 2 22 25 50 0).(crlEIF 2 22 22 2 )(crlEIF 2 22 2)(crlEIF 2 22 2)(crlEIF zyxxzFFxyzy22126624)15622(2)622121(22412121233 zI2 21 12 22 21 12 21 11 1)()(crlEIlEIFzzz )(3 33 322226 612121 12 21212242412121 1 yI2 22 22 22 22 22 22 21 1)()(crlEIlEIFyyy ,

4、mincrcrcr2 21 1FFF zy22126624 AlEIAF2 22 2)(crcr AIi 2 22 22 22 22 22 22 2)/()()(crcrilEilEAlEIAF il 2 22 2 E crcrcr AFPcr 2 22 2EPP EE 1 12 2令100100101020020010102062066 69 91 1 PEscr ba 1 12 2 bas bas 2 21 1 12 2 2 22 2)(crlEIF ba crscr iL cr 22 Ecr P S 21scr bacraFF1.3 a F1. 6 adABCA杆先失稳杆先失稳aFF1.

5、3 a F1. 6 adAal22 al3 . 11 aal12. 16 . 17 . 07 . 0 BC30mm20mmyz991 PE m0058. 002. 003. 0)02. 003. 0(1213 AIiyym0087. 0 AIizz15 . 0 zyuu30mm20mmyz11586 zzzyyyiluilu kN.crcr5 589892 22 2 zEAAF 1001001 1 P E222244414)(64)(dDdDdDAIi 1004122 dDlilm6 . 11404. 005. 010022min lm2 . 143min ll122754 dDlil 575

6、712121 12402403043042 2.sbbakN.)()(crcr5 51551554 42 22 2 dDbaAF stcrnFF stcrnFFn 86861 1 P E4dAIi 15 .62 il 2 24343.s2bbaMPacr301301 baMPacrcr478478 AF .stcrnFFn 5 51111pD活塞杆活塞dpD活塞杆活塞dN398042 pDF Nstcr2390023900 FnFAIi il 用试算法求直径用试算法求直径2 22 2)(crlEIF 2 24 42 22 22 26464)()(crldElEIF 2004 dlil 9797

7、1 1 P EABCF0.60.30.80 0 cm0 06 60 09 90 0 .sin.N FF8 . 06 . 08 . 0sin22 FF27272 2.N 991 PE 4dAIi ABCF0.60.30.8FN180 il572 bas 12 MPacr214214 bakNNcrcrFAF 268268 FFN27. 2 ABCF0.60.30.8直线平衡状态不变平衡形式发生变化达到限值小于限值 s变形前的形状、尺寸变形后的形状、尺寸实验确定理论分析计算强度问题强度问题稳定问题稳定问题,.)3 , 2 , 1 , 0(2 nnklEIFk ,.)3 , 2 , 1 , 0(222 nlEInF 2 22 2lEIF crmxmBxylFwkxklwsin2sin kllxwsinscr ba 1 12 2 bas bas 2 21 1 12 2 2 22 2)(crlEIF ba crscr A杆先失稳杆先失