Numerical Simulation On Prepeller-Induced Pressure Fluctuation

With the development of shipbuilding project in the word , the main engine power of ships increase gradually, but the diameter of screw propeller can't be increased excessively by various restrictions, thus the load of single-screw propeller increases gradually, the serious stern vibration ofen occurs inlarge or medium ships, the vibration can cause serious harms such as structure crack, vibration in chamber exceeding criterion propeller cavitation, etc. the main cause of serious stern vibration of ship is due to pressure fluctuations on hull surface induced by a propeller operating(ed) in non-uniform wake, therefore it is completely necessary to predict the pressure by theoretical calculation.This paper has adopted the low-order ssurface panel method based on velocity potential to predict the unsteady performance of propeller, has described the basic formula of surface panel methed , boundary conditions, numerical solution methed in details, has discussed the problem which is related to solution accruracy, and compiled computer program.Presently most of the theoretical method to predict the propeller-induced hull pressure fluctuation is based on the calculaton in which the pressure is induced by pulsating source in infinite flow.The wall factor is adopted to stand for hull boundary condition, and is considered as 2 in general, this paper adopted new mothed,, we distribute source on hull surface to stand for boundary condition ,this method can solve the question on any hull surfacee shape , we don' t need to take the hull surface as a plate, and by the calculation wo get a good result we need.