The orientation distribution of tiny Brownian oblate spheroidal particles suspended in a turbulent channel flow along with their generated non-Newtonian stresses are studied numerically. The direct numerical simulation of turbulent channel flow is coupled with a direct Monte-Carlo simulator for the particles conformation. The effects of particle shape factor and the intensity of rotary Brownian motion on the rheology of the suspension are studied. The root-mean-square of non-Newtonian stress fluctuations is computed and discussed. It is found that thinner disks produce higher stresses than thicker disks. Thin disks result in significantly higher normal stress differences. A significant level of shear stress adjacent to the wall is observed for thicker disks, which suggests a significant stress deficit for a suspension of such particles. Unlike rod-like particles, the level of shear stress is always higher than the normal stress differences for disks. It means that the shear viscosity of suspension is always more significant than its extensional viscosity.

数值研究了湍流中悬浮的微小布朗扁球形球体的取向分布及其产生的非牛顿应力。湍流通道流动的直接数值模拟与直接的Monte-Carlo模拟器相结合，用于颗粒构象。研究了颗粒形状因子和布朗运动的旋转强度对悬浮液流变性的影响。计算并讨论了非牛顿应力波动的均方根。发现较薄的磁盘比较厚的磁盘产生更高的应力。薄盘会导致法向应力差异大得多。对于较厚的圆盘，在壁附近观察到很大程度的剪切应力，这表明此类颗粒的悬浮液存在明显的应力不足。与棒状颗粒不同，剪应力水平始终高于圆盘的法向应力差。这意味着悬浮液的剪切粘度始终比其延伸粘度更重要。