Undergraduate Research at the US Coast Guard Academy Dr. Susan - PowerPoint PPT Presentation

Undergraduate Research at the US Coast Guard Academy Dr. Susan Swithenbank SNAME Philadelphia April 20, 2011

Recent Research • Scaling Effects of a 100 ft tow tank • Stern Flaps on the 378’ Cutter • Resistance of Bow Bulbs • Marine Bio ‐ Fouling of 110’ CG Cutters • Simplified Stability Tests • Corrosion

Tow Tank Scaling Effects

Stern Flaps on 378’ Cutters Percent Reduction in EHP overBare Hull Morgenthau Flap Flap 2 Flap 3 Flap 4 16 kts 7.24% 15.60% ‐ 7.84% ‐ 4.87% 17 kts 13.93% 16.58% ‐ 0.79% 2.15% 18 kts 12.85% 18.69% 3.10% 3.24%

Resistance of Bow Bulbs Economic Viability: Bulb 2 (12.3 ft) Total Cost ($) 427315 Savings per patrol ($) 43627 Patrols per year (180 days) 4 Years to Pay Off 2.4 Rendering of hull and bulb in Rhinoceros 4.0

Marine Bio ‐ Fouling of Cutters

Simplified Stability Testing • Vessels must obtain at least 10 foot-degrees of Righting Energy. • Vessels must have at least 15 degrees of heel until Downflood.

Corrosion Background • Current corrosion Issues – Exhaust tube corrosion – Buoy deck crack corrosion – Bilge Corrosion – Cavitation errosion corrosion – Stern Tube Corrosion – Slot weld corrosion

Research Team • 3 current students • Two professors from – One 1/C Cadet (Senior) chemistry, Dr Joshua – Two 2/C Cadets Gray and LT Jody (Junior) Maisano • One from USCGA • One from USNA

Experiments • Mass loss versus dimensional measurements of corrosion • Corrosion rates versus salinity of water • Different commercially available coatings to reduce the rate of corrosion • Different methods of simulating the bilge environment (stir bars versus rotating tables) • Different inhibiters to reduce corrosion rate • Using sacrificial anodes inside the bilge

Questions?

Corrosion Acknowledgements • Dr Joshua Gray and LT Jody Maisano of USCGA • CAPT Paul Roden, CDR John Gage, Larry Wilkerson, Mark Dust, Gary Peters, and John Kerns of the Coast Guard Surface Force Logistics Center • Dr. Glen Frysinger, LCDR Greg Hall, and Dr Todd Taylor of the USCGA for their support of the project • Rich Grassia and NSWCCD Philadelphia for their help and expertise