Given the level of liquid in a tank, what is the volume? Or, given the volume, what is the level? These are two questions which GHS readily answers for any tank, large or small, simple or extremely complex. The tank may be on a ship, but it need not be. It can, in fact be any container of any liquid.
Tank levels may be specified by sounding (measured along an arbitrary line) or by ullage (or innage). Volumes may be specified directly or by weight or percentage of full.
Once the level is established, the following tank properties are calculated:
Tank tables showing selected properties as a function of volume or level in various formats are available, some with plots.
Two liquids of different densities may be loaded into the same tank such that it is kept full but the amount of the two liquids can vary. This applies especially to water-displaced fuel tanks.
Tanks can be modeled with an opening such that spilling occurs when inclined.