Large eddy simulation of turbulent flows with property variations, rotation and complex geometry

Abstract

A comprossiblo finite voluinc fortuulalioii for largo eddy simulation IWLS been exleiuled to solve a variety of (lows by using dynamic subgrid-scale stress model and dynamic Prandtl number model. The basic features of this finite volume fornmlatioii include a dual time stepping approach with time derivative preconditioning, an implicit low-upper symtiietric Gauss-Seidel scheme, multiblock framework, and parallelization using message pa-ssing interface. riie impleiiUMitation of the dynamic motlel w;us validated by simulating a jjlane channel flow with constant heal flux. Good agreement between the present results and benchmark results in the literature wa.s achieved. Rotating channel flows with heat transfer were sequentially studietl by adding a rotation source term. The effects of .sjstem rotation on the turbulent heat transfer was investigated. Finally, a ril>-roughened channel flow wjus simulatetl without heat tran.sfer and with a heat flux on both walls. The influence of the rib on the How w:us studied. The large eddy formulation with a dynamic model generally provided excellent agreement with direct numerical simulation results and experimental results for turbulent flows with heat transfer (e.g. a plane channel flow, a rotating plane channel flow and a riI)-roughened channel flow). For the constant heat flux channel flows, high heating tends to rcnluce the velocity fluctuations, while high cooling tends to enhance the fluctuations. The mean and fluctuation velocity profiles collapse toward the incompressible results when normalizetl by local properties, as opposed to wall values. The spanwise system rotation was found to suppress turbulent velocity fluctuations and shear stress near the stable side of the channel, but enhance those fluctuations and shear stress near the unstable side. .Mso. turbulent temperature fluctuations and turbulent heat flux were decreased near the stable side of the channel, but increased near the unstable side of the channel. The existence of the rib creates a small recirculation