Abstract: It is an effective method to establish the mathematical model of ship maneuvering motion by using CFD (computational fluid dynamics) method to simulate the captive model tests to obtain the hydrodynamic derivatives. When the captive model tests of a fully appended ship are numerically simulated, the key issue is to select a suitable propeller modeling method to compute the hydrodynamic force on the ship efficiently and accurately. Using CFD method, the oblique-towing tests of a fully appended KCS ship model are numerically simulated by solving the Reynolds-averaged Navier-Stokes (RANS) equations. Both the body force method and the sliding mesh method based on real propeller are used to deal with the rotating propeller. By comparing the computed hydrodynamic forces with the benchmark data, the numerical method is verified. The results of the two methods for dealing with the propeller are compared, and it shows that considering the computation efficiency and accuracy, the body force method can replace the real propeller method to simulate the oblique-towing test of fully appended ships.

Key words: oblique-towing test, Reynolds-averaged Navier-Stokes (RANS) equations, body-force me-thod, sliding mesh method