Design analysis and optimisation of an integrated motor pump-jet thruster with improved resistance to cavitation

In order to meet the basic design requirements for high critical speed met, and anti-cavitation performance enhanced of Integrated Motor Pump-Jet (IMP) thrusters, a three-dimensional model of the IMP thruster using the blade parameter three-dimensional (3D) inverse design method was developed. The model utilises the shear stress transport (SST) turbulence model and the Zwart–Gerber–Belamri (Z-G-B) cavitation model. Then, based on the non-dominated ranking genetic algorithm and multi-objective parameter seeking theory to improve the IMP thruster's cavitation improvement optimization design. After optimisation, the hydrodynamic performance and anti-cavitation performance of the rotor blades were slightly improved. In order to further carry out the design of anti-cavitation performance, the oblique flow is introduced to further analyse according to the influence mechanism. The main focus was on the IMP thruster's excitation force, pulsation pressure and velocity distribution, the oblique flow angle had less impact than the cavitation number in the oblique flow field.