【摘 要】
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Virtual mass force is an indispensable component in the momentum balance involved with dispersed particles in a multiphase system.In this work the accelerating motion of a single solid particle is math-ematically formulated and solved using the vorticity-
【机 构】
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CAS Key Laboratory of Green Process and Engineering,Institute of Process Engineering,Chinese Academy
论文部分内容阅读
Virtual mass force is an indispensable component in the momentum balance involved with dispersed particles in a multiphase system.In this work the accelerating motion of a single solid particle is math-ematically formulated and solved using the vorticity-stream function formulation in an orthogonal curvi-linear coordinate system.The total drag coefficient was evaluated from the numerical simulation in a range of the Reynolds number (Re) from 10 to 200 and the dimensionless acceleration (A) between-2.0 to 2.0.The simulation demonstrates that the total drag is heavily correlated with A,and large decel-eration even drops the drag force to a negative value.It is found that the value of virtual mass force coef-ficient (Cv) of a spherical particle is a variable in a wide range and difficult to be correlated with A and Re.However,the total drag coefficient (Coy) is successfully correlated as a function of Re and A,and it increases as A is increased.The proposed correlation of total drag coefficient may be used for simulation of solid-liquid flow with better accuracy.
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