Numerical study on open water performance of L-shaped podded propulsor under deflection condition
Regarding the severe hydrodynamic instability issue induced by the deflection of podded propulsors,the open water performance of a L-shaped podded propulsor at different deflection angles was numerically studied with CFD methods and slide mesh technology.Results indicate that the thrust and torque of propeller and lateral force of pod unit increase with the increment of deflection angle.The deflection angle has minor influence on thrust coefficient and torque coefficient of propeller.At β=0°,due to the circumferential velocity induced by the propeller rotation,the podded propulsor is subject to lateral force even under straight-line navigation.When the podded propulsor deflectes to the right,the lateral force generated by the upstream side of pod is counteracted by that generated by the propeller rotation wake,resulting in a smaller lateral force compared to its deflection to the left.Furthermore,the mutual interference among the propeller rotation wake,the rear pod,and the support causes the overall thrust coefficient of podded propulsor to be asymmetric with straight-line navigation.Small deflection angles(|β|≤15°)have little effect on the overall thrust coefficient of podded propulsor,while at|β|>15°,the thrust coefficient decrease rapidly.
pod propelleropen water performancedeflection conditionthe numerical simulation