ACCURACY OF LARGE-EDDY SIMULATION FOR TURBULENT-FLOW BY THE FINITE-ELEMENT METHOD

This paper investigates the computational accuracy and CPU (central pr ocessing unit) time of large eddy simulation (LES) for turbulent flows performed by the finite element method. The investigations are accomp lished by simulating a fully developed turbulent channel flow, which w as analysed by Kim et al. using the direct numerical simulation (DNS) technique. When the advection term is discretized in gradient form, th e turbulence decays and disappears with the passage of time. In using a multipass algorithm to solve the velocity field, the numerical resul t obtained by discretizing the advection term in divergent form agrees very well with that of the DNS. The multipass algorithms with the num ber of iterations k = 2 and 3 predict almost the same results. Thus, t he algorithm with k = 2, allowing calculation with less CPU time, is s uccessfully applicable to LES.