A Stock Propeller Design for the High Speed Sealift Hybrid Contra-Rotating Shaft-Pod, Model 5653-3A
NAVAL SURFACE WARFARE CENTER CARDEROCK DIV BETHESDA MD SHIP HYDROMECHANICS DEPT
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A stock propulsor has been designed for the High Speed Sealift Hybrid Contra-Rotating Shaft-Pod. The forward propeller of the contra-rotating set is a standard shaft and strut mounted propeller. The aft propeller is driven by a COTS tractor pod. The full power speed of this design is 39 knots. The final design has a 21.5 foot diameter, five-bladed propeller forward and a 17-foot diameter, seven-bladed propeller aft. Both the forward and aft propellers operate at 113 RPM. Calculations predict that the design will achieve the 39 knot target speed without significant thrust breakdown. A final propulsive coefficient of 0.716 is predicted at 39 knots with 191,500 DHP 143 MW. A propulsive coefficient of 0.64 was measured for the same hull form with four shafts and struts at 39 knots and 231,300 DHP 172 MW. Therefore, this design predicts a 17 decrease in the required DHP. These propellers are currently being manufactured at model scale for open water and powering tests.
- Marine Engineering
- Military Operations, Strategy and Tactics