THE WAGENINGEN B-SCREW SERIES

Abstract

The Wageningen B-screw series have been extended gradually to 21 screw series having blade numbers ranging from 2 to 7 and blade-area ratios between 0.30 and 1.05. Recently, the existing screw series were correlated with the new screw series with an up-to-date fairing technique. This correlation was made by means of a regression analysis. Further, the influence of the Reynolds number ( scale effect ) on the test results was taken into account. For ship maneuvering studies, it is necessary to know the propeller thrust and torque characteristics over a wider range of operating conditions. Therefore, open-water tests with B-series screws over the entire region of operation were carried out. In order to obtain systematic knowledge on the cavitation characteristics of the B-screw series in a uniform flow, tests have been conducted. The curves for cavitation inception were established and the influence of cavitation on propeller thrust and torque was determined.