Energy-saving bow shapes for actual seas: COVE
ENERGY-SAVING BOW SHAPES FOR ACTAUL SEAS: COVE
Energy-saving bow shapes for actual seas; COVE(Concave shape Optimized in waVEs)
The COVE energy-saving bow for actual sea conditions is an energy-saving bow shape with a frame line that is carved inward from the static swellup line, and it saves about 10% of energy in actual sea conditions (wave height 3m).
Ship applying COVE while operating in actual seas
Original bow
Energy-saving bow shapes for actual seas COVE
（Compared to the original bow, COVE reduces the waves returning forward.）
| Design: | It works in actual seas without changing the performance in calm sea. |
COVE Outline
(By carving the frame line above the static swellup line inward, the performance in calm sea is not changed.)
| Verification: | By tank tests on VLCC, we have confirmed a reduction of approximately 40% in the added resistance (wave height: 2 m) in short wave length and heading waves. |
Verification results from tank tests
| Energy-saving Effect: | We conducted a performance calculation in actual seas using the results of tank tests on VLCC, and confirmed that COVE can reduce engine power by about 10% at 15 knots in head seas and head winds (significant wave height: 3 m, wind speed: 12.6 m/s). |
Comparison of Power Curves
References
- 櫻田顕子, 辻本勝, 黒田麻利子, 池本義範：COVE船首による波浪中抵抗増加の低減, 日本船舶海洋工学会講演会論文集, 第22号, pp.147-150, 2016.
- Akiko Sakurada, Masaru Tsujimoto, Mariko Kuroda: Development of COVE Bow -Energy Saving Bow Shape in Actual Seas, Proceedings of PRADS2016.