Research On Optimal Design Of Podded Propulsor's Hydrodynamic Performance

The 21st century is the century of marine, ocean makes the advancement of the Navy's role even more important. In January 2000, the then secretary of the Navy Richard Danzig announced that the United State's Navy began a new era and the next generation of surface warships of the United States Navy will use electric propulsion system. Before World War II , the United State's Navy abandoned the electric propulsion instead by gear driven machinery, electric propulsion has not been adopted. Richard Danzig's announcement provided a new opportunity (referring to using electric propulsion systems). In the commercial areas, especially in cruise ships, the electric propulsion has been used for many years.FLUENT software is designed based on the "CFD software group" and can be targeted at different flow characteristics, the use of appropriate numerical method, in calculating speed, stability, precision achieve optimum combination. In this paper, propeller hydrodynamic calculations are simulated by using the FLUENT. Without map CFD can be used as one of the means for propeller design and use of this means, the characteristics of the propeller's performance can also be calculated. The key to solve the problem is fluent modeling and simulation software, including catheters, propeller and their combination of the model to determine the appropriate control domain, the physical model and boundary conditions. With experimental data and the traditional pattern design, hydrodynamic performance of the catheter tube and propeller are optimized. The paper has mainly completed the following two aspect work:1) By carrying on two-dimensional and the three-dimensional modelling to the drive pipe and carrying on the numerical simulation computation under the condition of changing its basic parameter (coefficient of contraction, expansion coefficient, length to diameter ratio to compare, parallel and so on), drive pipe's flow field distribution and the hydrodynamic characters is obtained. Through analyzing the first series of drive pipe's computed result, some rules about pipe hydrodynamic influence by the geometric parameter changed is obtained. According to these rules and adjust pipe's size under the condition of the pipe laying aside the electrical machinery, the geometrical shape of the second series drive pipe is generated, also the similar numerical simulation is being carried on, finally the superior drive pipe satisfied the request about the performance is selected.2) Based on the mold of paddle blade of the ordinary pipe , the pipe of the first step optimized designation joined carry on the three dimensional was modeled. Selecting the appropriate calculational model and the related parameter, carrying on the numerical calculus under the different operating mode to the model, the corresponding thrust force relation of distribution is obtained. Comparing the test result with the numerical calculus result , regarding the situation of the error's size between them, readjusts the computation model and the related parameter until the satisfactory result was abtained, Then the suitable numerical procedure of this model is obtained.The compare of numerical results with test show that the numerical method of this thesis can be used for the simulation and forecasting of catheter propeller on the hydrodynamic performance, which would reduce design costs and enhance efficiency.