The influence of inertial migration of neutrally buoyant particles on inertial flow transitions in Taylor-Couette (TC) flow of a suspensions is studied; this work considers primarily transitions associated with the circular Couette flow (CCF) and Taylor vortex flow (TVF) regimes. A concentric cylinder Taylor-Couette device with a stationary outer cylinder and rotating inner cylinder is considered. The device has an inner to outer radius ratio of $\eta =d_i/d_o=0.877$, where $d_i$ and $d_o$ are the inner and outer diameters of the flow annulus. The ratio of the axial length to the radial gap of the annulus $\mathrm{\Gamma }=L/\delta =20.5$, where $\delta =(d_o-d_i)/2$. The ratio of radial gap $\delta$ and the particle diameter $d_p$ is $\alpha =\delta /d_p=30.4$ and the particle volume fraction considered in this work is $\varphi =0.10$. A flow structure (CCF or TVF) near the transition boundary with either uniform distribution across the annular region or fully migrated concentration profile is established. The Reynolds number (Re) is subjected to a rapid step change to study the effect of the concentration profile on the flow transition Re and resulting flow structure evolution; here the Reynolds number is $\text{Re}=\delta d_i{\omega }_i\rho /2{\mu }_s$, where ${\omega }_i$ is the rotation rate of the inner cylinder and $\rho$ and ${\mu }_s$ are the density and effective viscosity of the suspension. Our results show that, relative to uniform concentration, the particle distribution following inertial migration destabilizes the CCF state near the CCF-nonaxisymmetric flow transition boundary. In contrast to this destabilizing effect in CCF, migration of particles in the TVF regime has a stabilizing effect on the TVF-wavy Taylor vortex and TVF-nonaxisymmetric flow transition boundaries. The transition away from the TVF exhibits clear hysteresis associated with migration, as once initiated TVF could be sustained below and above the transition boundaries observed for suspension TC flow with uniform concentration.

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颗粒的惯性迁移对悬浮液泰勒-库埃特流的流动过渡的影响

研究了中性浮力颗粒的惯性迁移对悬架的泰勒-库埃特（TC）流动中惯性流变的影响；这项工作主要考虑与圆形库埃特流（CCF）和泰勒涡流（TVF）体制相关的过渡。考虑了具有固定的外圆柱体和旋转的内圆柱体的同心圆柱体泰勒-考特装置。该设备的内外半径比为$\eta =d_{\mathrm{一世}}/d_{Ø}=0.877$，在哪里 $d_{\mathrm{一世}}$ 和 $d_{Ø}$是流动环的内径和外径。环的轴向长度与径向间隙之比$\mathrm{\Gamma }=\mathrm{大号}/\delta =20.5$，在哪里 $\delta =（d_{Ø}-d_{\mathrm{一世}}）/2$。径向间隙比$\delta$ 和粒径 $d_p$ 是 $\alpha =\delta /d_p=30.4$ 并且在这项工作中考虑的粒子体积分数是 $\varphi =0.10$。在过渡边界附近建立了一种流动结构（CCF或TVF），该流动结构在整个环形区域内分布均匀，或者浓度分布完全迁移。对雷诺数（Re）进行快速阶跃变化，以研究浓度曲线对流变Re和流结构演变的影响；雷诺数是$\text{回覆}=\delta d_{\mathrm{一世}}{\omega }_{\mathrm{一世}}\rho /2{\mu }_s$，在哪里 ${\omega }_{\mathrm{一世}}$ 是内筒的旋转速度， $\rho$ 和 ${\mu }_s$是悬浮液的密度和有效粘度。我们的结果表明，相对于均匀浓度，惯性迁移后的颗粒分布使CCF-非轴对称流动过渡边界附近的CCF状态不稳定。与CCF中的这种不稳定作用相反，TVF区域中的颗粒迁移对TVF波浪状泰勒涡旋和TVF非轴对称流动过渡边界具有稳定作用。离开TVF的过渡表现出与迁移相关的明显的滞后现象，因为一旦启动的TVF可以在均匀浓度的悬浮液TC流动观察到的过渡边界之上和之下维持不变。