Loads on impermeable nets and large volume objects in AquaSim (TR-FOU-2328-5)
Summary
This document describes how hydrostatic- and hydrodynamic forces are calculated in AquaSim for the load formulation General impermeable nets, including Lice skirt, Closed compartment, and Surface tarpaulin.
Verifications of the numerical calculation of diffraction forces by comparing MacCamy Fuchs and numerical solution to analytical solutions for cases where the water is acting on a stiff object. Further, the report outlines a load model for a fully flexible tarp and shows how to combine this load model with the diffraction load model to obtain a hybrid load model applicable for tubes or lice skirts.
Revision 7:
- As from AquaSim version 2.19.1, the load formulation for calculating drag and lift forces to membrane panels have been modified. Theory for the revised formulation is given in section 2.2.1. Case studies in section 3 updated according to changes in solver 2.19.1. This includes comparison of tank test and AquaSim analysis of a tube.
Revision 8:
- Corrections Table 1.
Revision 9:
- Corrections section 2.6.
Revision 10:
- Added section 2.1.2 Internal pressure and static equilibrium, section 2.4 MacCamy-Fuchs, 2.5 Numerical diffraction, section 2.8.1 wave drift forces on impermeable nets.