Numerical solutions of three-dimensional unsteady compressible viscous
flows for several cases have been obtained using two time-marching pr
ocedures: a noniterative alternating direction implicit (ADI) scheme a
nd a generalized minimal residual (GMRES) method using an iterative ve
rsion of the ADI scheme as a preconditioner. Results obtained are comp
ared with each other and also with experimental data. It is found that
the GMRES scheme can reduce CPU time by as much as 60% compared to th
e noniterative ADI scheme.