A CFD based Kriging model for predicting the impact force on the sphere bottom during the early-water entry

Abstract

To efficiently achieve an accurate trajectory of the ocean observation device with a spherical bottom when it is thrown into the sea in the airdrop deployment, a computational fluid dynamics (CFD) based Kriging model is established for predicting the impact force on the sphere bottom during the early-water entry stage which is considered as the beginning of a full immersion process. The early-water entry of a sphere is simulated using the Reynolds-Averaged Navier-Stokes (RANS) method and k–ϵ turbulent model and the validity of the CFD model is verified by the comparison with experimental data. A Kriging surrogate model is then established based on the results of CFD simulation and extensive sample points where a proper range for the correlation parameter of the Kriging model is achieved through a study on the effect of the correlation parameter on the results from the Kriging model. The comparison with the CFD simulation results shows that the established Kriging model significantly improves the computational efficiency while maintaining high numerical accuracy.