Study On Maneuverability Hydrodynamic Force Of Submarine In Several Propeller Situations

Maneuverability is an important component of submarine(submersibles)comprehensive performance,and maneuvering hydrodynamic coefficient is an important index to evaluate submarine handling performance.It is very important to estimate and predict its hydrodynamic coefficients accurately and reliably during the design and finalization of submarines.In the procedure of predicting the hydrodynamic coefficients of submarines,the effect of submarine propeller operating conditions on hydrodynamic coefficients is usually not considered.In reality,compared to bare hull(without propeller),flow field will change when the hull fits with propeller(with propeller but no rotation);at the same time,the complex flow field generated by the rotation of a submarine propeller(with propeller rotation),and its flow field will be perturbed by the flow around the submarine.Both the propeller fitting and rotation affect the submarine maneuverability hydrodynamic coefficient.In this paper,using computational fluid dynamics(CFD)method to obtain the hydrodynamic coefficients of submarine model pitch under three different conditions(without propeller,with propeller but no rotation,with propeller rotation),writer complete the captive model test.Comparing the the calculation results with experimental values,analyzed the interference effects of the propeller wake field of submarine hydrodynamic coefficients.This paper uses the software named STAR-CCM+ to complete the related CFD calculation.The CFD computing is mainly based on trim volume mesh method and overlapping grid mesh method.In order to ensure that the flow field of propeller rotation simulation is similar to the experimental environment,the individual propeller is taken as an object.Simulation of of propeller in the open water situation is conducted at different velocity coefficients(J).Taking thrust coefficient,torque coefficient and open water propeller efficiency as evaluation indexes,the open water characteristic curve is drawn.The reliability of STAR-CCM+ simulated propeller rotation is verified by comparing with experimental results of open water experiment.In this paper,a submarine model is taken as an object,and the model is simulated under oblique motion,straight rudder motion and vertical plain motion.The submarine model was simulated under three conditions(without propeller,with propeller but no rotation,with propeller rotation).The DBFI model is used to simulate the simple harmonic motion on the vertical surface of the submarine model.In order to forecast the accuracy of CFD method is studied at the same time,the use of planar motion mechanism in circulating water channel(PMM)of captive model tests,completed the demolition paddle,closing pitch,oblique motion,pitch three under the conditions of variable rudder angle direct motion,vertical harmonic motion test,data processing and access to relevant water power coefficients were compared and analyzed.By comparing the CFD value with the experimental data,it can be seen that the numerical simulation values of CFD are in good agreement with the experimental values,and the first-order hydrodynamic coefficients agree with the highest ones,and the two order hydrodynamic coefficients are not ideal.By contrast,closing pitch,dismantle the propeller hydrodynamic coefficients that paddle under three conditions: both the calculated values and experimental values,the development trend of the hydrodynamic coefficients in “without propeller”,“with propeller but no rotation”,“with propeller rotation” conditions of hydrodynamic coefficient is basically the same.The CFD method can be used to approximately estimate the first order hydrodynamic coefficients and the stall angle of the rudder airfoil,which has higher accuracy.The tail flow field of propeller has some influence on hydrodynamic coefficients,and the prediction of submarine maneuverability should take into account the influence of propeller state.