We were asked by our clients to quantify the forces due to sloshing in a ballast tank. The client had unfortunately not examined modifications and the certifying authority found that the size of the ballast tank was not within the required dimensions to avoid sloshing issues.
A Computational Fluid Dynamics (CFD) model was created to simulate the movement within the tank at various levels and different motions. We modelled the tank at the natural frequency of the tank and also at the highest vessel motion.
The value to the client was that the CFD modelling was able to show that under the most extreme vessel motion that the dynamic loads from the sloshing were within reasonable limits – avoiding expensive additional unplanned time in dock to add additional bulkheads to address the issue.