Reply To: multi-block approach
Ok – as the VTK Output logic is independent of the specific platform the block lattices are processed on, I suspect that there is an issue with how you enabled and use the GPU support.
Did you compile using both the GPU_CUDA platform and MPI? (e.g. following config/gpu_openmpi.mk)
How did you launch the code on the cluster? Each GPU needs to be assigned to one process, one example is provided in config/gpu_openmpi.mk. However the way to do this is quite specific to each cluster.
(I suspect that the results of the single GPU block 0 encompass the entire lid driven cavity? This would basically guarantee that the issue is missing MPI support / wrong startup)