MPP Solution of Rayleigh - Bénard - Marangoni Flows

A domain decomposition strategy and parallel gradient-type iterative solution scheme have been developed and implemented for computation of complex 3D viscous flow problems involving heat transfer and surface tension effects. Special attention has been paid to the kernels for the computationally intensive matrix-vector products and dot products, to memory management, and to overlapping communication and computation. Details of these implementation issues are described together with associated performance and scalability studies. Representative Rayleigh- Bénard and microgravity Marangoni flow calculations on the Cray T3D are presented, and performance results verifying a sustained rate in excess of 16 gigaflops on 512 nodes of the T3D have been obtained. The work is currently being extended to the T3E and we have begun carrying out further performance benchmarks and scalability studies on this platform. Preliminary performance studies have recently been carried out and sustained rates above 50 gigaflops and 100 gigaflops have been achieved on the 512 node T3E-600 and 1024 node T3E-900 configurations respectively.