A New Simulation Method for the Installation of Subsea Structures from the Splash Zone to the Ultra Deep

Existing simulation methods are not able to determine in detail the wave loads on a complex subsea structure when it is passing through the splash zone. To determine these loads, model tests are necessary. Otherwise only simplified formulations or empirical relations for added mass and damping can be used. The improved Volume Of Fluid (iVOF) method presented in this paper is a potential candidate for the better numerical prediction of the behaviour of a subsea structure in the splash zone. The simulated flow around and through the structure looks very realistic and shows a strong resemblance with observations from model tests. The quantitative comparison of the vertical load on the subsea structure shows that the total load levels are well predicted. This good initial comparison shows the potential of the improved Volume Of Fluid (iVOF) method for the simulation of the behaviour of subsea structures in the splash zone. However, significant further development and validation is needed before a fully coupled simulation of a subsea structure and its lifting vessel in waves can be carried out. This possibility is also affected by the long simulation times required at the moment. As an intermediate step the method might be used to determine the wave loads and added mass in an uncoupled simulation.