Analysis of basset force of article motion in turbulent flows with spectral method

摘要

Using the spectral method from the Lagrangian particle motion equation, the particle motion statistics in solid- liquid turbulent flows, including the particle Lagrangian ener- gy spectrum, autocorrelation function and turbulent diffusivi- ty, were analyzed. The effects of the basset term on these statistics were examined. It is found that the Basset force may be neglected in the Lagrangian equation of particle motion only when a dimensionless number N is very small and the particle diameter, in general, is less than 0.1 mm. The numerical re- sults indicate that the particle diffusivity may exceed the fluid diffusivity for significantly long period.