Numerical and experimental investigation of the fluid flow on a full-scale pump jet thruster

Abstract

In the present study, a post-swirl pump jet system was designed for an axisymmetric underwater vehicle. In order to evaluate the design procedure, several experiments such as bollard pull, self-propulsion point (SPP) and bare hull resistance tests were conducted in a towing tank on a full-scale model. Further conditions were performed numerically at higher velocities to determine the characteristic chart and flow pattern analysis. Both open-water and behind-hull conditions were simulated. The Realizable k-ε turbulence model and the Mixing-Plane Method (MPM) were utilized in a periodic domain for numerical simulations. The obtained results showed that the variations of hydrodynamic coefficients, especially the torque coefficient, against advance coefficient were much smaller than conventional propellers. Moreover, the net imbalance roll moment was quite small in all conditions suggestive of accurate stator design. The stator also created additional thrust and hence increased the overall performance up to 82 percent in the behind-hull condition.