Implicit unfactored implementation of two-equation turbulence models in compressible Navier–Stokes methods

✍ Scribed by G. Barakos; D. Drikakis

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 268 KB
• Volume: 28
• Category: Article
• ISSN: 0271-2091
• DOI: 10.1002/(sici)1097-0363(19980715)28:1<73::aid-fld700>3.0.co;2-r

✦ Synopsis

An implicit unfactored method for the coupled solution of the compressible Navier -Stokes equations with two-equation turbulence models is presented. Both fluid-flow and turbulence transport equations are discretized by a characteristics-based scheme. The implicit unfactored method combines Newton subiterations and point-by-point Gauss-Seidel subrelaxation. Implicit-coupled and -decoupled strategies are compared for their efficiency in the solution of the Navier -Stokes equations in conjunction with low-Re two-equation turbulence models. Computations have been carried out for the flow over an axisymmetric bump using the k -and k -models. Comparisons have been obtained with experimental data and other numerical solutions. The present study reveals that the implicit unfactored implementation of the two-equation turbulence models reduces the computing time and improves the robustness of the CFD code in turbulent compressible flows.