Parallel SPH on CrayT 3 E and NECSX - 4 using DTS ?

In this paper we report on the results of a joint eeort of astrophysicists and computer scientists to develop and implement a parallel program that enables us to solve large systems of hydrodynamic equations and covers a wide range of applications in astrophysics. We introduce the Distributed Threads System (DTS) as an environment for the development of portable parallel applications. The numerical method Smoothed Particle Hydrodynamics (SPH) is used to simulate the viscous spreading of an accretion disk around a massive compact object as an astrophysical test problem. The SPH code was parallelized using DTS and successfully ported to systems of diierent architecture. The use of a parallel SPH code on supercomputers enables us to treat astrophysical systems that were not accessible before. The achieved speedup proves the eeciency of DTS as a parallel programming environment. The physical results show the consistency and accuracy of the SPH method.