Hydrodynamic Energy Saving Enhancements for DDG 51 Class Ships

Abstract : In February 2011, the U.S. Navy accepted its 60th DDG 51 Class destroyer, and there are still many more to be built. Propulsion fuel efficiency on this class thus becomes a fertile area for cost saving. NSWCCD has recently embarked on the design of an initial Stern End Bulb for potential retrofit on the DDG 51. Powering evaluation via computational fluid dynamics methods and scale model testing has been completed for an initial stern end bulb design. The speed improvement and the potential fuel saving is presented. In addition, updated fuel savings potential associated with many previously proposed hydrodynamic improvements such as the DDG 51 retrofit bow bulb, a larger diameter propeller, propeller pitch sensor and setting of optimal pitch, stern flap design, twisted rudder, and hull and propeller cleaning, are discussed and fuel savings are estimated.