SUMMARYIn this paper, we investigate the parallel solution of rotating internal flow problems, using the Navier-Stokes equations as proposed by Speziale and Thangam (in 1983) and Speziale (in 1985). A Runge-Kutta timestepping scheme was applied to the equations and both sequential and message-passing implementations were developed, the latter using MPI, and were tested on a four-processor SGI Origin200 distributed, global shared memory parallel computer and on a 32-processor IBM 9076 SP/2 distributed memory parallel computer. The results show that our approach to parallelize the sequential implementation requires little effort whilst providing good results even for medium-sized problems.