Research On Prediction Method For Propeller-Induced Hull Surface Pressure Fluctuations

According to the linearity vibration theory this paper adopts Wilson-θ method to program to calculate the response provoked by definite motivation, and then inversely calculates the actual propeller exciting force by using the actual measurement, this belongs to the approximate treatment of load identification problem. The results of this method are among the other approximate algorithm results.The writer studies deeply on the algorithm of exciting force, and aggregately analyzes the influence parameters. In response to the relationship between cavitations and wake gradient, this paper puts forward 3 kinds of calculating model of propeller exciting force, then puts the actual exciting force into pattern formula, and then obtains a new formula to predict propeller-induced hull surface pressure fluctuations by analyzing and calculating some actual ships. Then applies this formula to predict 4 vessels, the result compared with other overseas methods is within the scope of them. The prediction error percentage of the 52000t all-purpose cargo ship compared with the model test result is 21.8%, 300000t VLCC compared with the measured value is merely 3.64%.With the actual vibration response measurement data, the result of the new method is more close to the actual situation, so the formula is more accurate than other methods.