프로펠러 표면의 생물 부착이 프로펠러 성능에 상당한 영향을 미치지만 프로펠러 표면 거칠기와 관련된 연구는 상대적으로 선체 표면에 비하여 많지 않다. 본 연구에서는 Schultz(2007)가 발표한 Granville’s similarity-law scaling 절차에 기초하여 실선 7 m 크기의 탱커 프로펠러에 표면 부착물 상태가 서로 다른 3가지 경우를 고려하여 프로펠러 단독 효율의 감소의 변화를 Lifting surface code를 사용하여 수치적 계산을 수행하여 효율을 비교하였다. 본 논문에서의 결과는 표면 거칠기가 큰 석회질 부착물(ks=0.001)은 선박 설계 속도(J=0.5)에서 최대 15 %의 프로펠러 효율 감소를 보였음을 확인하였으며 이는 선박 운항 시 생물 부착에 의한 효율 감소에 대한 평가가 고려되어야 한다는 점을 나타내고 있다.

The effect of propeller surface roughness condition on ship performance is very significant even the influence of fouling on propeller performance is not well established compared to biofouling on the hull surface. In present study, predictions of open water efficiency of propeller are made for three different fouling conditions, and its application is given for the 7m full-scale propeller of a medium-size tanker in open water condition. The numerical predictions of propeller efficiency loss due to fouling are based on the results from laboratory-scale drag measurements and boundary layer similarity law analysis presented in Schultz (2007) together with an in-house unsteady lifting surface code which is an appropriate tool to predict the effect of propeller surface roughness on propeller performance. The results of this study indicate that the subject propeller with the small calcareous fouling (ks=0.001) can lead to as high as 15 % loss at the propeller operating condition (J=0.5) and the loss of propeller efficiency due to fouling should be evaluated while the ship is operating.

• Kwang-Cheol Seo(Department of Naval Architecture and Ocean Engineering, Mokop National Maritime University, South Korea) | 서광철 Corresponding Author
• Mehmet Atlar(Emerson Cavitation Tunnel, School of Marine Science and Technology, Newcastle University, UK)
• Bonguk Goo(Department of Naval Architecture and Marine Engineering, Changwon National University, South Korea) | 구본국