I'm new to Cosmosworks. I have to analyze a tank design for strength. It's a simple rectangular tank that sits on three supports. It will be filled with essentially water. What I need to verify is that I'm defining the water load correctly. I have the bottom of the tank restrained as fixed. it will be botled in place. Then I added a gravity perpendicular to the bottom of the tank. Last I added a distributed load equal to the mass of the water inside and selected the bottom and the four walls.

The results of the simulation are bothersome. The bottom deflects downward as expected. Two walls deflects outward. The other two wall bulge toward the inside of the tank. The tank is almost square so I'm at a loss as to why this would happen. It does not seem to be distributing the pressure fo the water to the side walls.

I assume that a proper pressure load would be the answer?

Greg