A Characteristic Domain Splitting

This work treats a linear convection-diiusion problem. Diiusion and convection may be equally important or convection may dominate the problem. The method of characteristics is combined with an overlapping domain decomposition technique so that domain decomposition is naturally combined with the time stepping. In each time step, the algorithm rst determines the characteristic solution. Then a diiusion problem is solved in parallel on each subdomain with the characteristic solution as boundary conditions. No iteration is needed between the subdomain problems. Adaptive time steps are used for the characteristic tracing. The time steps used for the diiusion problems can be large.