Investigations on different propeller types

Article type: Research Article

Authors: Oosterveld, M.W.C.

Affiliations: Netherlands Ship Model Basin, Wageningen, The Netherlands

Abstract: This paper presents the results of open-water tests with different propeller types (the Wageningen B-screw series, ducted propeller series with nozzles of both the flow accelerating and decelerating type and contra-rotating propeller series). A discussion of the fairing of the results of such tests by means of a regression analysis is given. For systematic screw series, for instance, the thrust and torque will in future be given in the form of polynomials of the advance coefficient, pitch ratio, blade-area ratio and number of blades. The effect of the Reynolds number (scale effect) will also be taken into account in these polynomials. For the ducted propeller series and the contra-rotating propeller series the thrust and torque will be given in the form of polynomials of the advance coefficient and pitch ratio. The derived polynomials enable design calculations and analysis to be done with a computer in an easy way. Finally some special applications of ducted propellers and contra-rotating propellers are discussed. In the case of ducted propellers attention is paid to nonaxisymmetrical nozzle shapes which mayi be attractive for minimizing problems relating to propeller induced vibrations and cavitation in single-screw ships (tankers) and twin-screw ships (fast naval ships). Finally, the specific field of application of contra-rotating propellers and of the overlapping twin-screw stern arrangement is discussed.

DOI: 10.3233/ISP-1971-1819802

Journal: International Shipbuilding Progress, vol. 18, no. 198, pp. 32-55, 1971