How does the buoyancy model work?
Overall buoyancy is governed by the summation of the weight of the diver and the buoyant force acting upon him. A set number of times every second the resultant force is calculated and used to calculate the acceleration of the diver (positive or negative). It is the change in buoyant force with depth that causes the diver to gain uplift as he approaches the surface, and is the reason why a diver must dump air from his buoyancy jacket as he ascends.
How does the acceleration model work?
When an object moves through a liquid, it encounters an opposing drag force. The exact calculation of this force can be complex, and so Diver-Sim uses a simple model that is related to the density of water and the velocity of the diver. It was considered that a good 'feel' and speed to the simulation was preferable to a more accurate model in this case.