Fully Resolved Large Eddy Simulation as an Alternative to Towing Tank Resistance Tests - 32 Billion Cells Computation on K computer

摘要

The demand for towing tank tests has been increasing due to the requirements of the EEDI (Energy Efficiency Design Index) imposed by IMO (International Maritime Organization) as a measure for controlling CO_2 emissions from ships. Although numerical simulations by RANS (Reynolds-averaged Navier-Stokes) have been widely used in the early stage of hull design, the prediction accuracy has to be further improved for such simulations to become a complete alternative for towing tank tests. In particular, for resistance tests and self-propulsion tests, the relative error to the experimental data has to be reduced to 1%. By tuning the turbulence models, RANS simulations may provide such accuracy. But, it seems difficult for RANS simulations to always guarantee such accuracy for different types of ships.