Numerical Simulation of Laminar Diffusion Flames

Not too long ago, anyone wanting to solve large science or engineering problems had to rst get access to a supercomputer costing millions of dollars. Quite recently, a new breed of relatively inexpensive work stations became widely available. These machines have scalar peak speeds of 30{275 mega ops with ones on the horizon of 400 or more (which compares rather favorably with vector supercomputers of not so long ago). While these rates are only seen for simple problems like dense matrix{matrix multiplication, the rates seen for many problems are quite high. In this article, we describe a class of problems which can now be solved on machines individuals can a ord to own rather than just on ones costing millions of dollars. Of course, the problem with using a single one of these machines is that the option of connecting a collection of machines together or buying a parallel version of the work station becomes more and more tantalizing. In fact, during the course of two years we did all of the above. We started on a single machine with a 100 mega op peak rate (an IBM RISC System/6000 model 560 computer). Then we used a farm of the IBM's, an IBM SP1, and nally an SP2. Due to a nice feature of the communications' library we used (EUIH), the executables worked on the ethernet at Yale or on the fast switches in the SP1/SP2's without either recompiling or relinking.