Optimization Of Duct Of Integrated Motor Propulsor And Research On A Strength Checking Method Of Blade

IMP (Integrated Motor Propulsor) is a new foreign underwater propulsion system which integrated Motor and pump jet propulsion. Looked from the structure, IMP is a collection of podded propulsors and ducted propellers. In IMP thrusters, the motor stator (core and winding) installed in the duct, the rotor (permanent magnet pole) installed at the tip of with rings propeller blade leaves and appeared in the form of rings. This new type thruster is especially suitable for ships, UUV, torpedoes whose cabin and energy carrier space are rather limited. The national Research on IMP thrusters is later than international, and so far it is just in the foundation level, compared with foreign technology there is still a long way to go.In this paper, selected nacelles catheter IMP thrusters with propeller shaft as the calculational object, adopted CFD software FLUENT as the platform, combined with the propeller’s hydrodynamic knowledge, to simulate and calculate hydrodynamic performance of propeller. The thesis has mainly completed the following work:1) Catheter type optimization. In order to get better propulsive efficiency and higher thrust coefficient,after studying different kinds of catheter types and analyzing varies ducted propeller’s open water performance, selected three excellent catheter types. Adjust the selected catheter size to make sure lay the electrical machinery aside, thus generate new ones and make them as the IMP thrust’s catheters. By carrying on modeling of the new IMP ducts and propeller blades as a whole, analyzes catheter hydrodynamic performance, Chose the best one model, and set it as the first thruster model.2) Catheter parameters optimization. Analysis the influence of each catheter parameter on duct hydrodynamic performance, and set the first thruster model as foundation, by changing the most important parameters(length-diameter ratio, shrink coefficient, expansion coefficient)to derived for the series IMP thrusters model. Modeling and simulating IMP thruster with FLUENT software, analyze the law of catheter geometrical parameters on performance. Finally list the most excellent catheter geometrical parameters. 3) IMP thruster blades strength check method research. It mainly viewed on finding out the law of both propeller blade thickness distribution and leaf profile stress distribution in the conditions of satisfying the intensity. Without changing IMP thruster’s hydrodynamic performance, the thickness of each section will be reduced to a minimum. That is to say guarantee the profile of the maximum stress equals to the material allowable stress, at the same time ensure the fairness of both pitch and blade thickness distribution along the radial direction.The calculational results in this paper are well agreed with the test data, the error are in engineering tolerance. It shows that the numerical method can be well used in simulation and prediction of IMP thruster’s hydrodynamic performance. The research significance of this paper lies in the following two aspects:①It designs a new excellent performance IMP thrusters catheter by studying the main parameters of IMP propeller catheter and figuring out the law between thruster performance and catheter geometrical parameters②It is the first time to provide a reference method for IMP thruster blades strength checking.