Study on Separated Flow around Ships at Incidence

Abstract

In the previous report, separated flow field around prolate spheroid at incidence was investigated experimentally and numerically. Based on these results, the separated flow field around ships at incidence is investigated in the present report. In order to confirm and extend the knowledge obtained about the nature and structure of the separated flow field, the measurement of the surface pressure distribution, the measurement of velocity distribution by use of 5-hole pitot tube and the flow visualization are carried out. From experimental results, the characteristics of the separated flow and its relation to the lateral force are discussed. Vortex layer configuration and lateral force distribution are calculated numerically by considering the shedding of vortex sheet, based on a slender body approximation. The comparison between the calculated lateral force distribution and measured one shows the consideration of viscous diffusion and dissipation at the bottom of ships is necessary to obtain the agreement between them.