Electromagnetic field modeling on supercomputers

The relatively new area of problem solving on supercomputers offers exciting new possibilities for numerical solution of 3-D electromagnetic field problems. The solution of systems of equations with tens of thousands of unknowns and bandwidths in the thousands is all but impossible on conventional computers. The availability of new vector supercomputers such as the CRAY 1 and the CYBER 205 brings both hope and new challenges. The faster machine cycle, vector instructions and parallel computing combined with advanced I/O devices promises to speed up the solution of large problems considerably. On the other hand, efficient programming on such machines is far from being trivial and in most cases, one has to compromise portability of the code. In addition, these machines require a front end computer and are not interactive, complicating and lenghtening the program development process. This work presents an overview of the work done to date on electromagnetic field modeling on supercomputers. Some data on field solution on an attached array processor is also included since array processors are a special class of supercomputers and for comparison purposes. Using some very large eddy current problems the various aspects of computing are presented together with results showing dramatic improvements in solution times. The problem of code portability, vector complex computation and program conversion are also addressed and, finally, the need for new algorithms, specifically designed for vector computing is presented.