磁流变液剪切屈服应力的数值分析.pdfVIP

35 4 Vol. 35 No. 4 2006 7 Journal of China University of Mining T e hnology Jul. 2006 : 1000- 1964( 2006) 04-0498-06 朱应顺, 龚兴龙, 李 辉, 张培强 ( , , 230027) : 为了改善单链模型的准确性, 从颗粒间的磁相互作用能出发, 建立了磁流变液多链计 模 型. 考虑链内颗粒和相邻链中颗粒的影响, 利用磁能密度的变化, 得到了磁致剪切应力应变关系, 由剪切应力应变曲线的最大值来确定磁流变液的剪切屈服应力. 对于链状结构, 研究了链间距与 链内相邻颗粒距离之比对磁流变液剪切屈服应力的影响; 对于柱状结构, 通过确定柱的大小及相 邻柱的间距, 构建了BCT 结构计 模型, 对含柱状结构的磁流变液的剪切屈服应力进行了分析. 计 结果表明, 当比值较大时, 多链模型与单链模型趋于一致; 比值较小时单链模型的误差不能 忽略. 传统的单链模型高估了磁流变液的剪切屈服应力, 铁磁颗粒体积比浓度较小时, 链状结构 有比柱状结构更高的剪切屈服应力; 而当颗粒体积比浓度较大时, 柱状结构优于链状结构. : 磁流变液; 剪切屈服应力; 磁偶极子 : O 373; T B 381 : A Numeri al Analysis on Shear Yield Stress of M agnetorheologi al Fluids ZHU Ying- shun, GONG Xing-long, LI Hui, ZHANG Pe-i qiang ( Department of Me hani s and M e hani al Engineering , U niversit y of S ien e and T e hnology of China, Key Laboratory of Me hani al Behavior and Design of Materials, Chinese A adem y of S ien e, H efei, Anhui 230027, China) Abstract: In order to improve the a ura y of urrent models based on the single hain, a multi- hain model w as presented for the magnetorheologi al fluids( MRF) based on the magnet- i intera tion energy among the parti les. T aking a ount of the influen es of parti les in the same hain and the parti les in all adja ent hains, making use of the variety of the magneti energy density , a model w as proposed to al ulate the relationship of shear stress versus shear strain indu ed by the magneti field, and the shear yield str ess of magnetorheologi al fluid w as identified as the max imum shear stress as a fun tion of str ain