Research On Hydrodynamic Performance Of Electric Ducted Propeller

With rapid development of semiconductor technology,AC Speed-Governing theory and microcomputer control technology,the variable frequency Speed-Governing technology of AC motor have been daily mature,and electric propulsion technology is strongly concerned again.Various forms of electric propulsion systems are developed consequently.The structural character of the electric ducted propeller studied in this thesis is the propeller tip is covered by a ring with a certain width,the ring is embedded in duct,and a very small clearance exists between the ring and the internal wall of duct. Motor stator and duct are integrated,while rotor and propeller are integrated.This kind of structure avoids the disadvantage exists in common electric propulsion system,which contains an excessively heavy motor,there is basically no shaft wasting as well.Similar structure has been applied for torpedo propulsion on abroad, but in China this is the first time,for the purpose of practical application of this propulsion,previous period research is carried out in this paper.Based on computational fluid dynamics software,combined with theoretical knowledge of fluid dynamics,the software FLUENT is adopted to simulate and calculate hydrodynamic performance of electric ducted propeller.The thesis mainly deals with the following work:1) Research of hydrodynamic calculation for electric ducted propeller:Select testing model of electric ducted propeller as research model and calculate its hydrodynamic performance,compare the results with tests,analyze reliability of the physical modeling and computational modeling,then further demonstrate the rationality of calculated results.2) Research on optimization of duct geometric parameters for Electric ducted propeller:by the premise of fixedness of propeller with ring,create a series of electric ducted propellers,base on numerical simulation to obtain their hydrodynamic performance.Analyze whether the duct design of electric duct propeller can directly adopt the optimization results of duct without propeller or not. 3) Research the influences of duct geometric parameters on hydrodynamic of electric ducted propeller:by the premise of fixedness of propeller with ring,change duct geometrical parameters,analyze the results of numerical calculation,analyze the influence regular of changing duct geometric parameters on hydrodynamic of electric ducted propeller,and choose the duct shape which makes the performance of electric duct propeller optimal.By comparing calculating results and experimental results,as well as the standard ducted propeller,the results show that the numerical calculation method used in this thesis can simulate and predict the hydrodynamic performance of electric ducted propeller;and give the regulation that how the performance of electric ducted propeller will change with various parameters of duct,these research results will provide theoretical and practical evidence for the design of electric ducted propeller in the future.