| In this paper,the structure of the RDT is simplified reasonably,and the propeller and pipe are modeled and simulated.On this basis,the structure optimization strategy of the RDT blade is proposed,and its hydrodynamic characteristics and trends are summarized and analyzed.In this paper,based on the research of traditional propeller,the existing shaft drive mode is improved,and the hubless flange drive is adopted.The combination of central shaft and blade is changed to the combination of flange and blade,and the brushless DC motor is used to drive the flange,so as to drive the blade to rotate.In order to ensure the structural strength and hydrodynamic performance of the propeller,the thickness distribution of the propeller must be adjusted due to the change of the combination mode of the propeller.The new paddle thickness distribution is obtained by two steps of re-determining the thickness center of the paddle and the corresponding displacement thickness value.The three-dimensional coordinates of the blade were obtained by threedimensional coordinate transformation,and the simplified model of the RDT propeller was created.STAR-CCM+ software is used to simulate and analyze the open water performance of the simplified model.Secondly,the design parameter range of the blade is determined,the algorithm model is selected to establish the approximate model,and the error analysis is carried out for the approximate model to ensure that the output and input of the approximate model are consistent with the original sample relationship.The results show that the two approximate models based on RSM and RBF have good reliability.In addition,the principal component analysis is carried out to obtain the quantitative index of the influence of each design parameter on the optimization objective,which provides the basis for the following structural optimization.Then,the Muti-Island GA was selected as the multi-objective optimization algorithm,the optimization parameters were set,and the optimization process was initialized to start the optimization.As the number of iterations increases,two sets of optimized parameters based on RSM and RBF approximation models are finally obtained.Combined with the previous simulation process and method,the two groups of parameters are simulated and verified.The results show that the model obtained by RBF design is better than the model obtained by RSM design in all performance measures.Finally,the housing of the RDT was designed and fabricated,and the protection work of all the workpieces was completed.For the design of the shell,referring to the design idea of the traditional thrusters,the RDT are designed as three sections,that is,the center of gravity of the shell is the propeller,the front and rear are the self-lubrifying bearings,and the tail is the shell cover,which improves the workpiece integration.The workpiece protection work is mainly completed from three parts: material,coating and structure design,which improves the overall corrosion resistance of the RDT push machine. |
