A multiphysics approach to the direct numerical simulation of turbulent flows on parallel computers

Abstract

The objective of the present work is the simultaneous solution of different physical problems on local memory parallel computers in the frame of the computational Direct Numerical Simulation (DNS) of turbulent flows. The background is the investigation of the influence of compressibility on the turbulence properties as the flow is subjected to a rapid isentropic expansion, as for the flow through a Laval-Nozzle. Our approach to the parallel treatment of such physically complex flow simulations can be described as a heterogeneous “task-shearing” problem. The DNS-part, i.e. the time accurate integration of the Navier Stokes equations, is solved on a chosen number of parallel processors, while a synthetic turbulence field is generated as a separate task on one separate processor to provide suitable boundary conditions for the DNS. Similar coupling-problems arise e.g. in the simulation of fluid / structure-dynamics interactions. The target computer of the present work is the Meiko CS-2.KeywordsTurbulent Kinetic EnergyDirect Numerical SimulationTurbulent Velocity FieldDivergent NozzleInflow Mach NumberThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.