Flo52 on Hypercubes: Performance and Modelling of a Multigrid Euler Code

This paper evaluates the performance of hypercube machines on a computational fluid dynamics problem. Our evaluation focuses on a prototype of a class of widely used fluid dynamics codes, FLO52, written by Antony Jameson, which solves the two-dimensional steady Euler equations describing flow around an airfoil. In this paper, we give a description of FLO52, its hypercube mapping, and the code modifications to increase machine utilization. Results from two hypercube computers (a 16 node iPSC/2, and a 512 node NCUBE/ten) are presented and compared. In addition, we develop a mathematical model of the execution time as a function of several machine and algorithm parameters. This model accurately predicts the actual run times obtained. Predictions about future hypercubes are made using this timing model.