CFD-based Numerical Analysis of Amphibious Vehicle Hydrodynamics during Turning Motion

Abstract

Amphibious vehicle has blunt bow and multi appendage structure, and its flow field characteristics are very complicated during maneuvering. In this paper, a simplified model of amphibious vehicle with propulsion device is established, and the thrust volume force model is introduced to consider the pumping and water jet propulsion of the water effects jet propulsion device. The technique of overlapping grid is used to deal with the six-degree-of-freedom large-scale hull motion problem, and study the turning motion of amphibious vehicle under different rudder angles. The results of numerical simulation show that the amphibious vehicle will enter a stable turning state when turning on the water surface, but the heel angle is large, the draft depth and the speed drop are significant. The state of water baffle has a significant influence on vehicle trim and roll motion. Larger vehicle pitching motion amplitude will increase the risk of overturning.