Yield stress in magnetorheological and electrorheological fluids: A comparison between microscopic and macroscopic structural models
Yield stress in magnetorheological and electrorheological fluids: A comparison between microscopic and macroscopic structural models
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DOI：
10.1122/1.550838
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发表时间：
1997-05-01
影响因子：
3.3
通讯作者：
Clercx, H
中科院分区：
文献类型：
--
作者：
Bossis, G;Lemaire, E;Clercx, H
磁流变悬架的屈服应力通过两种不同的方法计算。第一个基于结构的介观描述，仅考虑应变聚集体的形状各向异性。第二种方法基于微观方法，其中通过考虑聚集体内部颗粒之间的静磁力，对由于施加场而产生的颗粒间力进行数值计算。我们表明，宏观描述很好地适用于铁磁流体中非磁性颗粒的悬浮液，并且由可磁化材料的平行板组成的层状结构应具有比由圆柱形聚集体制成的结构高得多的屈服应力。另一方面，微观方法适用于描述高渗透性颗粒的悬浮液。在这种情况下，屈服应力主要由颗粒对之间的破裂决定，因此，屈服应力随着发生破裂的颗粒对的中心线与场之间的角度而强烈增加。 (C) 1997 年流变学会。
The yield stress of a magnetorheological suspension is calculated from two different approaches. The first one is based on a mesoscopic description of the structure taking only into account the shape anisotropy of the strained aggregates. The second one is based on a microscopic approach where the interparticle forces, due to the application of the field, are calculated numerically by taking into account the magnetostatics between the particles inside the aggregates. We show that the macroscopic description well applies to suspensions of nonmagnetic particles in a ferrofluid and that a layered structure, consisting of parallel slabs of magnetizable materials should have a yield stress much higher than a structure made of cylindrical aggregates. On the other hand the microscopic approach is appropriated for the description of suspensions of particles of high permeability. In this case, the yield stress is mainly determined by the rupture between pairs of particles and, consequently, it strongly increases with the angle between the line of centers of the pair undergoing the rupture and the field. (C) 1997 The Society of Rheology.