A Study on Analysis Method of Resistance Test by using Circulating Water Channel

Abstract

Analytical considerations given to the effect of blockage and inclination of water surface of circulating water channel (CWC) show the necessity of a correction to the resistance test by CWC. Through the comparison of resistance test results of the towing tank (TT) and CWC, a correction method for the result of CWC is proposed by correcting effects due to the blockage and inclination of water surface. The proposed correction method covers practical type of ships ranging from thin to blunt. Through the comparison of the results of TT, the corrected results show the potential of CWC resistance test using a small model ship. Furthermore, it is clarified how the shape factor and the wave-making resistance coefficient obtained in CWC differ from the towing tank test results. Finally, as an application, a method is proposed that can be corrected even if the data of the type ship is not available. The estimation accuracy of this method is quantitatively evaluated, and it is proved that it can be corrected to the level of the towing tank using a large model.