Herschel-Bulkley模型下磁流变减振器旁路泊肃叶流动分析

Analysis of byroad Poiseuille flow in magnetorheological damper based on the Herschel-Bulkley model

制备了羰基铁粉(CIP)的质量分数为70%的硅树脂基磁流变胶。用安东帕MCR-301型流变仪对其流变特性进行了测量,并对测试结果进行了Herschel-Bulkley本构模型参数识别。最后对MRG-70在该模型下磁流变减振器旁路中的泊肃叶(Poiseuille)流动展开了分析。试验及分析结果表明,在外加磁场下,Herschel-Bulkley本构模型中非牛顿指数n<1。剪切应力随半径的增大而线性增大;当τ_r>τ_y形成剪切流,反之则为柱塞流动。在剪切流动区域内,流速随半径增大而非线性降低,剪切速率随半径增大而非线性增大。磁感应强度越大,柱塞流区域越大,柱塞流区域内剪切速率恒为0。体积流量随磁感应强度增强而非线性减小。在0mT～500mT之间体积流量随磁感应强度变化剧烈,进一步增加磁感应强度则变化缓慢。

A kind of magnetorheological gel based silicone resin with the mass fraction of 70%for CIP is prepared,and its rheological characteristic is measured used MCR-301 rheometer.Parameter of Herschel-Bulkley constitutive model is identified.At last,the Poiseuille flow in the bypass of magnetorheological damper based on this model is analyzed.The results of test and analysis show that the non-Newton exponent n<1 under the applied magnetic field.The shear stress increases linearly with the increase of radius.The shear flow is formed whenτ_r>τ_y,and conversely the plunger flow appears.In the shear flow area,the velocity decreases nonlinearly with the increase of radius;and the shear rate increases nonlinearly with the increase of the radius.The greater the magnetic induction intensity,the larger the plunger flow area,and the shear rate in the plunger flow area is zero.The volume flow is decreases nonlinearly with the increase of magnetic induction intensity.When the magnetic induction intensity is between 0 mT^500 mT,the volume flow rate changes violently,and it changes slowly when the magnetic induction intensity is further strengthened.