I want to model a block that has its gravity force balanced by pressure. So far I apply the force due to gravity to all elements (-rho_b g, where rho_b is the density of the block material and g is acceleration due to gravity), with a global load, and pressure on the bottom face (rho_w g h, where rho_w is the density of water and h is the height of the block "underwater" assuming the block is already in equilibrium) with a face load.
Is this the correct way to go about this? I get wildly incorrect results, with the block flung far away by the first increment.
