Lattice Boltzmann Direct Numerical Simulation of Taylor-Couette Flows with a Grooved Wall

Abstract

To investigate the difference between the standard Taylor-Couette (TC) flow and axially grooved TC (GTC) flow, this study caries out DNSs of turbulent TC and GTC flow by the D3Q27 MRT lattice Boltzmann method．For the GTC flow calculated in this study，the inner rotating cylinder has no grooved and outer stationary cylinder has 24 axial grooves. From statistical results，it is found that Case GTC has a lower bulk velocity than Case TC．The kinetic energy of fluctuating velocity in Case TC has a nearly symmetric distribution，while in Case GTC，as the Reynolds number increases， the maxima are larger on the inner cylinder side than the outer cylinder side．In Case GTC，Nu_ω − 1，which is directly related torque，is 30% larger than the normal TC flow．This means that the torque required for rotation is increased due to the grooves．However，for the groove geometry in this study，the increase in torque is not as large as for the ribroughened TC flow in a similar study.