Abstract: To improve the navigational stability of high-speed amphibious vehicles and reduce the pitch of the amphibious vehicle when encountering waves, a single vector water jet thruster system that can keep heading and adjust attitude is designed and applied to a model amphibious vehicle, as opposed to a multi-thruster configuration. Based on the Moving Reference Frame method for rotational basins, the RNG k-ε model is used to calculate the output thrust of the vectored waterjet thruster. Combined with the thrust results from the CFD calculations, joint vortex simulations are used to calculate the sailing characteristics of the amphibious vehicle fitted with vector water jet thrusters. The free-running heading-keeping experiment and forced-running pitch-reduction experiment are carried out on the towing pool model vehicle to verify the functions of the thruster. The simulation and experiment results show that the thruster can, to a certain extent, reduce the amphibious vehicle's pitch amplitude when encountering longitudinal waves during navigation, and the standard deviation of the vehicle's pitch is reduced by 38% and 23%, respectively, in the two pitch-reduction experiments. The vector water jet thruster also allows the amphibious vehicle to maintain a stable heading during navigation, and the lateral displacement of the vehicle is less than 0.6 m in the heading-keeping experiment.

Key words: amphibiousvehicles, vectoringwaterjetthruster, heading-keeping, pitchreduction, amphibiousvehiclestanktest