Stress Characteristics of High Viscosity Non-Newtonian Fluid in Wedge Flow Channel under Acoustic Vibration

This study examines the stress characteristics of high viscosity non-Newtonian fluids in a wedge-shaped channel under acoustic vibration using CFD methods. The analysis focuses on the distribution of compressive and shear stresses, and the effects of vibration amplitude and frequency on these stress characteristics. At low vibration intensity, high fill flow occurs within the channel, with compressive stress increasing spatially in different directions and shear stress exhibiting a block-like distribution. At high vibration intensity, the fill rate decreases. The high compressive stress is concentrated in point-like areas on the upper and lower walls, while high shear stress is found at the inlet, outlet, and walls. As amplitude and frequency of vibration increase, compressive stress initially increases, then decreases, and subsequently rises again, while shear stress first stabilizes and then increases. However, the periodicity of both stresses gradually weakens, and their fluctuation intensifies. Under the same acceleration, the combination of low frequency and high amplitude vibration is more effective in achieving full-field dispersion in the liquid phase, reducing compressive stress without excessively increasing shear stress.

本研究运用计算流体动力学（CFD）方法，探讨在声波振动作用下，楔形通道中高粘度非牛顿流体的应力特性。分析重点在于压缩应力和剪切应力的分布情况，以及振动幅度和频率对这些应力特性的影响。在低振动强度下，通道内部发生高填充流量，压缩应力在不同方向上空间性增加，剪切应力呈现块状分布。在高振动强度下，填充率降低。高压缩应力集中于上下壁面的点状区域，而高剪切应力出现在进口、出口及壁面上。随着振动幅度和频率的增加，压缩应力起初增加，随后降低，继而再次上升；剪切应力则先稳定后增加。然而，两种应力的周期性逐渐减弱，其波动强度逐渐加剧。在相同的加速度下，低频高幅振动组合在实现液体相的全场分散方面更为有效，能够在不过度增加剪切应力的同时，降低压缩应力。