Journal of the Korean Society of Marine Environment & Safety (해양환경안전학회지)

The Korean Society of Marine Environment and safety (해양환경안전학회)
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Numerical Study on Effect of Longitudinal Center of Gravity (LCG) Changes on Cruise-Ship Resistance in Shallow Water

천수 효과를 고려한 무게중심과 수심 변화에 따른 유람선의 저항성능에 대한 전산유체역학 해석 연구

  • Michael (Graduate School of Mokpo National Maritime University) ;
  • Kwang-Cheol, Seo (Department of Naval Architecture & Ocean Engineering, Mokpo National Maritime University) ;
  • Kyoung-Woo, Lee (Department of Naval Architecture & Ocean Engineering, Mokpo National Maritime University)
  • 마이클 (국립목포해양대학교 대학원) ;
  • 서광철 (국립목포해양대학교 조선해양공학과) ;
  • 이경우 (국립목포해양대학교 조선해양공학과)
  • Received : 2024.07.09
  • Accepted : 2024.08.29
  • Published : 2024.08.31
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Abstract

Owing to the interaction between a ship and the river bed, several phenomena resulting in increased resistance may have occurred. This increase in resistance is primarily due to the wave-making performance. Thus, this study aims to reduce the wave-making resistance by optimizing the performance of an electric canal cruise through changing the longitudinal center of gravity (LCG). Numerical simulations are performed to obtain the lowest resistance by optimizing the LCG position; subsequently, the ef ect of water depth is included as the next variable. Results show that LCG variations of 37.5%-52.5% Lpp can result in a wide range of total resistance. In deep water, a 72.67% resistance gap is achieved by comparing the highest and lowest resistances, whereas a slightly lower gap of up to 62.97% is achieved in shallow water. Additionally, smaller water depths correspond to higher resistance. The resistance increased by a maximum of 67.68% in shallow water measuring 1.5 m, as compared with the case of deep water. This increase in resistance is primarily due to wave-making resistance, which constitutes 84.99% of the total resistance.

얕은 물에서 선박과 바닥의 상호작용으로 인해, 제한이 없는 깊은 물에서 운항할 때와 비교하여 저항이 증가하는 현상이 발생한다. 이러한 천수효과에 의해 증가하는 저항은 주로 조파저항에 기인하기 때문에, 본 연구에서는 유람선을 대상으로 LCG(Longitudinal Center of Gravity)의 위치 변경을 통해 성능을 최적화하여 조파저항을 감소시키는 것을 목표로 진행하였다. 수치해석 시뮬레이션을 통해 LCG 위치를 최적화하여 저항의 최소값을 찾고, 이후 수심의 깊이에 따른 영향을 분석하였다. 분석 결과, 37.5% - 52.5% Lpp의 영역에서의 LCG 변화는 총 저항에 큰 영향을 주었으며, 깊은 물의 조건에서는 총 저항의 최대값과 최소값을 비교하였을 때, 72.67%의 큰 차이를 보이는 반면, 얕은 물 조건에서는 그 차이가 62.97% 정도로 비교적 낮은 차이를 보인다. 수심의 깊이에 따른 효과는 수심이 낮을수록 총 저항이 증가하는 경향을 보였다. 깊은 물과 비교하여 1.5m의 얕은 물에서는 총 저항이 최대 67.68% 가량 증가하는 것으로 분석되었다. 이 경우 총 저항 증가의 주요 원인은 전체 저항의 84.99%를 차지하는 조파저항에 의한 것으로 판단된다.

Keywords

Acknowledgement

This research was supported by "Regional Innovation Strategy(RIS)" through the National Research Foundation of Korea(NRF) funded by the Ministry of Education(MOE)(2021RIS-002).

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