Experimental Researches on Rudder Performance

Abstract

The present paper relates to experimental researches on rudder performance utilizing a free-running, self-propelled model.
Similarity between a free-model and an actual ship concerning their rudder torques, which mean a hydrodynamic moment about a rudder stock, may be assured by attaching an air-propeller to a model to provide an additional thrust that is necessary for skin friction correction.
Alternative tests have been carried out for three different balance ratios and a procedure to estimate a rudder torque in steering for an arbitrary balance ratio has been provided through analyzing the test results.