In front of the growing demand for natural gas, alternative solutions have been adopted to export the production to the several available markets. Conventional gas carriers have been converted to regasification units to operate close to the shore, treating the gas and delivering it to carriers which take the product to the shore. Side by side configurations for the gas transference by loading arms are common, and the reduce distance between the ships is the main challenge.
For such application a time domain simulation is demanded. Due to the close proximity between the ships, at each time step, their distance has to be calculated in order to predict eventual ship to ship or ship to fenders collisions.
When the ships are modeled by conventional meshes the interference analysis every time step is excessively time consuming, the use of parametric surfaces reduces the number of elements to be checked against each other and saves computational cost. The precision is also improved since the hull shapes are fully represented in comparison to the panel approximation provided by the meshing approach.
The contact verification plays a fundamental role for that type of analysis and the gains obtained by the parametric surfaces appliance are significant.