Structure Design Of Mini Hubless Propeller And Research On Propeller Configuration

As a power source for underwater robots,the performance of the thruster affects the overall performance of the machine.This article first designs the overall structure of the thruster.The main design parameters of the propeller are determined according to the influence of different propeller parameters such as disc surface ratio,pitch ratio,side slope angle,and pitch angle on the hydrodynamic performance.In the process of propeller modeling,make full use of the method of surface modeling,adopt the design method of atlas method,and obtain the three-dimensional space coordinates through the coordinate conversion formula of the twodimensional value point coordinates,and at the same time consider the influence of the blade thickness changes,design one A new thickness variation curve.Finally,a three-dimensional model of the propeller blade is established by inserting curves,stitching curved surfaces,constructing entities,etc.;the type value points on the curve of the blade are encrypted by interpolation,and different interpolation functions are analyzed to analyze the results.Carried out the verification and simulation of the numerical calculation method of hubless propeller.The correctness and feasibility of the simulation method are verified according to the numerical simulation results and test results of the catheter propeller.Different turbulence models are used to compare the influence of the turbulence model on the simulation results.The results show that the calculated values under the RSM turbulence model are closest to the experimental values,and the calculated values are in good agreement with the experimental values,indicating that this model has good calculation accuracy.The numerical simulation model of the four-blade hubless propeller was established.Through the uncertainty analysis of the model grid,the influence of the mesh density on the simulation results was analyzed.By establishing a better simulation model,the effects of wake and propeller surface pressure and rim on propeller flow lines are analyzed.By comparing the data of the forward and reverse movement of the propeller,it is found that the internal speed of the forward propeller is moreturbulent,and the internal flow velocity of the reverse propeller is regularly arranged,because the direction of the forward and reverse rotation is different,which makes the direction of the surface velocity of the propeller opposite.By contrast,the general law of forward and reverse propellers is similar,and the thrust of reverse rotation is relatively reduced.Predict the effect of different propeller configurations on hydrodynamic performance.The effects of different blade numbers and inner diameters of different diameters on hydrodynamic performance were compared.When the number of blades of the propeller increased,the thrust coefficient,torque coefficient,torque and thrust of the propeller increased,but the propulsion efficiency did not change much.The simulation results of the hub-type propeller and the hubless propeller are compared,and it is found that the hub-less propeller is superior to the hubtype propeller in terms of thrust,torque and efficiency.