I am a research student working on a CFD problem using Fortran. The code has to simulate flow of bubbles over a cylindrical body. So bubbles are being injected in a flow field moving in the direction of cylinder. The motion of the bubbles have to be tracked as well as other parameters like change in diameter and local pressureare to be measured. Since a large number of bubbles have to be injected, therefore parallel processing is required using MPI. PROBLEM I am facing right now is that when I am running the code using only one processor it's working correctly but when I increase the number of processors than it starts writing wrong values. If anyone have faced anything like this before or have any experience in this PLEASE HELP. P.s If you need to look into the code I can upload that too.