Parallelisation and Appplication of Viscous Codes VASBI and RANS3D on PACE+

Abstract

The design and analysis codes VASBI and RANS3D have been made operational on the PACE+ parallel computer. The parallel version of VASBI was validated to BPPS computer and ported to PACE+ computer using the BARC message passing library available on PACE+. RANS3D code has been parallelised using PACE message passing library routine after validating the sequential code on IBM RS6000/560 of Aeronautical Development Agency, Bangalore. A speed up of 18-22 with respect IBM RS6000/560 of ADA has been obtained for both codes with double precision calculations. The speed up remains fairly constant with increasing grid sizes on 32 nodes of PACE+ for the explicit code VASBI, but decreases for the implicit code RANS3D when communication between nodes is increased. The code VASBI was used to carry out several computations on two different ducts to compare the performance of the ducts for various conditions on 32 node PACE+.