Flow Field and Motion Characteristics of Trans-Medium Submersible during Take-off and Landing on Water Surface

Abstract

In order to explore the evolution of the flow field structure and motion characteristics of the trans-medium submersible during the take-off and landing on water surface, the volume of fluid(VOF) multiphase flow model, the shear stress transfer(SST) k-ω turbulence model, the Schnerr-Sauer cavitation model, and the Stokes fifth-order nonlinear wave theory were coupled to construct a numerical calculation method for the submersible during take-off and landing on water surface based on the numerical simulation technology of computational fluid dynamic(CFD). The take-off of the submersible on water surface in the static water environment, as well as its landing on water surface in the presence or absence of the wave was numerically simulated. The dynamic response, load change of the submersible, and the evolution of the flow field on free liquid surface in each process were analyzed. The results show that the submersible can maintain a stable attitude during the whole take-off process on water surface in a static water environment, and the flow field structure and free liquid surface evolution around it have strong symmetry. In the process of landing on water surface, the bottom of the submersible and the fairing are subjected to a large reverse attack force, making the submersible fluctuate to a certain extent, but it can quickly restore the steady state after several attenuation fluctuations. The existence of the wave will increase the attack load applied to the submersible at the moment of touching the water, aggravate the attitude fluctuation of the submersible, and delay the final recovery time of the attitude.

Keywords

• trans-medium submersible
• take-off and landing on water surface
• dynamic
• attack load