遷移レイノルズ数域の平板間クエット流れの直接シミュレーション

抄録

Fully developed plane Couette flow at the transitional Reynolds number is simulated numerically without any model representing the effect of turbulence smaller than the size of computational grids. Upwind scheme proposed by Kawamura and Kuwahara is applied to the direct integration of the three-dimensional, time-dependent Navier-Stokes equation of motion. In this study the procedure necessary to examine the equivalence of the numerical result to the real flow is considered, and the effect of numerical diffusivity of the upwind differencing is evaluated. From the numerical results, the outstanding features of the low Reynolds number wall turbulence are discussed. Furthermore, the model of small scale turbulence in Large-eddy simulation is also tested using the results of direct numerical simulation. It is infered that the Smagorinsky model can not be applied to the highly anisotropic turbulent shear flow of a low Reynolds number without any modification.