Thursday, August 2, 2012

Cobra Hydrodynamic Bow Bulb Testing Completed at NSWCCD

Naval Surface Warfare Center (NSWC) Carderock Division researchers completed two weeks of hydrodynamics testing to optimize the size and shape of bow bulbs aboard DDG 51-class ships.

Partnering with Program Executive Office (PEO) Ships and the Naval Sea Systems Command (NAVSEA) Fleet Readiness Research and Development Program, NSWCCD conducted testing as part of the Navy's overall initiatives to reduce fuel consumption.

Located near the waterline, the bow bulb is an inverted tear drop shape that protrudes from the hull and is designed to reduce the ship's wave resistance. Specifically, the bow bulb creates a wave designed to interfere with the existing bow wave which reduces the amount of drag on the ship as well as fuel consumption and engine exhaust emissions.

"It is my hope that the DDG 51 class bow bulb will parallel the success of previous [NAVSEA] sponsored designs such as the stern flap, and not just improve the capabilities of the Navy's combatants, but provide for a reduction in fuel consumption and for millions of dollars in cost savings as well," said Dominic Cusanelli, NSWC Carderock Bow Bulb testing project lead, who developed the current bow bulb design for use on a naval combatant in the early 1990s.

Through computational fluid dynamics, NSWC Carderock designed and evaluated more than 20 bow bulb prototypes for DDG 51-class ships. Following the evaluation, NAVSEA selected the four most promising bow bulb prototypes for fabrication and model testing. The model tests will identify the bulb design with the best potential for powering and fuel reduction.

The bow bulb testing is one of several innovative energy saving initiatives NSWC Carderock provides in order to support the Navy's overall efforts to reduce energy consumption, decrease America's reliance on foreign sources of oil and significantly increase its use of alternative energy. Additionally, NSWC Carderock engineers are constantly looking for ways to improve the performance of the Navy's surface Fleet based on rapidly changing technology.