Joint-Industry Effort to Develop and Verify CFD Modeling Practice for Predicting Wave Impact

Abstract In 2020, a modeling practice was presented to perform numerical simulation of waves, where waves generated by a numerical wave tank (NWT) were used as input to a CFD simulation. This paper presents an extension of those practices in the context of wave impact on a gravity-based structure (GBS). It focuses on capturing accurate wave loads for a prescribed wave event, reproduced from a measured time series. This modeling practice serves the purpose that if it is followed by a CFD practitioner, the CFD results are reproducible. The modeling practice is validated for two regular wave cases and one irregular wave event. The validation data are based on experiments performed at MARINTEK in model scale 1:54 with the water depth 2.81m. During the validation the wave time series are compared against model test without and with GBS at scale 1:54. Further, relative wave height time series, global forces and moments acting on the deck as well as slamming forces are compared against model test records. The modeling practice is validated with Simcenter STAR-CCM+ as the main CFD solution but the modeling strategy can be applied to other CFD software. Thanks to the initialization of the CFD solution with user defined waves (UDW), the NWT-CFD coupling shows two advantages. First, the size of the CFD domain can be reduced to a minimum. Second, it is sufficient to start the CFD simulation shortly before the impact event.