Research On Calculation And Prediction For Ship Resistance Based On CFD Theory

Ship resistance is one of the important factors which affect ship speed performance. Ship with good performance can not only enhance transportation efficiency and saving energy, but also has connection with ship economic performance. Prediction of ship resistance performance is an important basis of ship hull optimization. The prediction method for ship resistance is an eternal research topic in naval architecture engineering field. Research on calculation and prediction for ship resistance shows great academic significance and practical engineering value.This thesis reviews and summarizes recent developing history and research progress for the theoretical calculation of ship resistance systematically. It has a detailed introduction about the ship CFD developing trends and resistance prediction methods. Taking CFD method, we make numerical calculation for sailing ship based on the laminar and turbulence theories. Compare those calculation results to experiment for verification. Ship resistance from theoretical calculation can be divided into pressure force and viscous force, which are analyzed and compared with the residual force and friction force obtained from model ship experiment. Meanwhile, effects of ship hull wall roughness to resistance have been discussed. From those workings, we propose a method for predicting the ship resistance based on CFD theory.This thesis creatively divides ship resistance into two components and analyzes them. Put forward a method for research on ship resistance prediction. Research shows that fairly good results compared with model scale ship experiment result can be obtained from turbulence viscous theoretical calculation, but the simulation is time-consuming. It is not accurate enough to adopt laminar viscous model, but the simulation time is short and wave contours can be captured accurately. On the basis of comparing the coefficient of pressure force from model-scale and full-scale ship based on laminar viscous theory, the result shows that they have no great differences. The results obtained from laminar viscous theory simulations at high speed are corresponding to the result from model ship experiment. Enhancement of wall roughness under turbulence viscous theory can increase the ship resistance obviously.The research on calculation and prediction for ship resistance bases on CFD theories in this thesis. It shows great significance in leading the researchers to get new methods from doing some more deep and detailed research on ship resistance prediction in naval architecture engineering field.