Accession Number : ADA302540

Title :   A Contrarotating Propeller Design for a High Speed Patrol Boat with Pod Propulsion.

Descriptive Note : Final rept. Feb-Jun 89,

Corporate Author : NAVAL SURFACE WARFARE CENTER CARDEROCK DIV BETHESDA MD

Personal Author(s) : Chen, Benjamin Y-H. ; Tseng, Carol L.

PDF Url : ADA302540

Report Date : NOV 1995

Pagination or Media Count : 32

Abstract : A contrarotating (CR) propeller design with a tractor pod for a high speed patrol boat is addressed. In the current arrangement, a CR propeller is placed at the forward end of a pod which is aligned with the local inflow. The powering and cavitation experiments show the performance prediction agree well with measurements. Compared to the existing controllable pitch propeller with shaft and strut configuration, the pod-mounted CR propeller show a 28% reduction in power consumption at design speed with a 7 knot improvement in cavitation inception speed. At full power, a larger pod is required, which will reduce the gain in power consumption.

Descriptors :   *PROPULSION SYSTEMS, *PATROL CRAFT, *COUNTERROTATING PROPELLERS, HIGH VELOCITY, ANGLE OF ATTACK, CONFIGURATIONS, EXTERNAL STORES, POWER, FLOW, HYDRODYNAMICS, ENERGY CONSUMPTION, STRUTS, LOW NOISE, PROPELLERS, CONTROLLABLE PITCH PROPELLERS, PROPELLER BLADES, CAVITATION, PROPELLER STRUTS.

Subject Categories : Marine Engineering

Distribution Statement : APPROVED FOR PUBLIC RELEASE