Hydrofoil performance optimization based on the Kriging method

In order to design a new type of hydrofoil, which is much more useful in improving the seakeeping performance in the condition of the same projected area, an improved Kriging surrogate model-based optimization method coupled with an MSP-EI-MSE(Minimize Surrogate Prediction-Expected Improvement-Mean Square Error) parallel infill criterion is proposed in this study. The computing time needed is reduced approximately 22.46 % and the variance is reduced nearly 45.14 % compared with the existing methods. Subsequently, it is demonstrated by the application of the method to the hydrofoils of an unmanned catamaran that, the moment induced by the optimized hydrofoils in pitch motion is increased 19.59 % per unit area. Later, model test is adopted to validate results obtained in the simulation, Particle Image Velocimetry is used to obtain the details of the flow fields around the hydrofoils and analyze the effect caused by optimization.