Resistance Numerical Simulation And Calculation Method Reserachs Of Round Bilge & Angle High Speed Ships In Displacement

High speed ships in displacement usually have two varieties: type U and type V. The new high speed ship with both round bilge & angle has the respective advantages of angle line and round bilge type line, which has good resistance and sea-keeping performance. And the ships are widely used in water law enforcement and traffic pilotage etc. Ship resistance is one of the most important performance of ship. Research methods of ship resistance: theory research, ship model test and numerical simulation. In ship design process, the application of research methods of theory is more convenient, but on complex issues tend to get only basic qualitative solution. Ship model test is the most important method to solve the problem, can obtain the qualitative and quantitative results, but is often restricted by many conditions. Recently, with the development and perfect of CFD and the progress of numerical method, analysis and prediction of ship resistance by using the method of numerical simulation is favored.Round bilge ship, angle ship, and the ship with both round bilge & angle together with related resistance performance are analyzed in this paper. On this basis, selecting a ship with both round bilge and angle which has excellent performance as the research object. In this form as the mother ship, to derive a new type of ship, formed a series of ship.Then using NAPA software to conduct profile modeling on the series of ship. Through hydrostatic calculation module in NAPA, the related parameters of the ship in different draught can be obtained.In this paper, resistance numerical simulation for the mother ship is based on CFD. The simulation results are compared with the test values of ship model, used to verify the reliability of the method. Then through the application of the method, numerical simulation of resistance is carried out on the established series of ship, to obtain simulation values under different conditions in each type of ship. According to Froude assumed law, the resistance simulation results were collated, To obtain the residual resistance coefficient of each condition, thereby generating a relationship spectrum of residual resistance coefficient which corresponds to drainage length coefficient and Froude number, to provide a more efficient way for the resistance estimation of the high-speed ship with round bilge and angle.In order to achieve better analysis and purpose of rapid calculation of ship resistance and, using Visual Basic 6.0 to develop a program for calculating the resistance of the high-speed ship with round bilge and angle. This calculation program is divided into the residual resistance calculation module, the frictional resistance module, and the total resistance calculation module. In the resistance calculation program, through the input of relevant parameters, the program will automatically output the related numerical values, thereby estimating the resistance value quickly and accurately.In this paper, the atlas of residual resistance coefficient and the developed resistance calculation program have the certain reference value to the research of the ship resistance. They can provide an easy way to estimate the ship resistance and also have a certain practicality and engineering practical significance.