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Application of a parallel rotor CFD code on HPCx

Published online by Cambridge University Press:  03 February 2016

C. B. Allen ,
A. G. Sunderland  and
R. Johnstone
C. B. Allen
Affiliation:
Department of Aerospace Engineering, University of Bristol, Bristol, UK
A. G. Sunderland
Affiliation:
CCLRC Daresbury Laboratory, UK
R. Johnstone
Affiliation:
CCLRC Daresbury Laboratory, UK
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Abstract

Aspects of parallel simulation of rotor flows are considered. These flows can be extremely expensive for a compressible finite-volume CFD code, and parallelisation can be essential. The award of HPCx time through the UK Applied Aerodynamics Consortium has allowed large rotor simulations to be performed and wake grid dependence to be investigated. However, there are several issues that need to be investigated when considering very large simulations, including the grid generation process, the parallel flow-solver, including an effective mesh motion approach, and visualisation options. Details of these are presented here, with particular emphasis on the flow-solver parallel performance. A detailed performance analysis of the unsteady flow-solver has been undertaken and the code optimised to improve parallel performance, and details of the parallel scaling performance are presented. The parallel scaling of the code is very good on all the HPC architectures tested here, and this has been recognised by an HPCx Gold Star Capability Incentive award. Results of simulation of a fourbladed lifting rotor in forward flight are also presented, for two mesh densities. It is shown that the solution computed on the serial limit on mesh size, around four million cells, exhibits excessive diffusion, and is of limited use in terms of detailed flow features. The results on a very fine mesh, 32 million cells, have shown a much better solution resolution, and it is also demonstrated that the λ2 vortex core visualisation option is extremely useful.

Type
Research Article
Information
The Aeronautical Journal , Volume 111 , Issue 1117 , March 2007 , pp. 145 - 152
Copyright
Copyright © Royal Aeronautical Society 2007 

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