• Title/Summary/Keyword: Stop and underway

Search Result 2, Processing Time 0.018 seconds

Influence of Sail on the Reduced Rolling Motion of Small Ship (돛이 소형선박 횡동요 감소에 미치는 영향)

  • CHOI, Chan-Moon;AHN, Jang-Young
    • Journal of Fisheries and Marine Sciences Education
    • /
    • v.21 no.1
    • /
    • pp.68-77
    • /
    • 2009
  • In this study it will be discussed how to solve the problem of discomfort from rolling motion on the small fishing boats. Up to now, the equipments of reducing rolling system can be examined by various case, but difficult to apply small vessel by function, space and costly establishment. A way of improving the feeling of getting on a boat through the equipped sail at stern edge of bulwark top was researched and developed. The author has tested the sailing performance of the experimental skiff boat, from the signals obtained by the inclinometer in irregular waves and compared with the results got in sail on and off mode operation for 10 minutes duration at the conditions of stop and underway. These data has been analyzed in the application statistical methods. Eventually we summarize the analyzed results obtained from the vessel while stationary and underway for two cases, the vessel with a sail and the vessel without a sail. The field test was done in Jeju outer harbor. The ratio of the motion responses at resonance for the sail with and without cases indicate that under given conditions the motion was reduced by the efficiency of diminution is 4.726%, 2.792% in the stopping and 11.663%, 3.282% in the underway and mean rolling periods are 2.158, 2.142, 2.421, 2.412sec. and 1.968, 1.963, 2.089, 2.051sec. respectively. Consequently the efficiency of diminution was higher when the ship is underway and rolling periods got longer in the equipped sail.

A Study on the Performance of Active Anti-Rolling Tank Stabilizer System (능동형 횡동요 감쇠장치의 성능에 관한 연구)

  • Choi, Chan-Moon;Ahn, Jang-Young;Lee, Chang-Heon
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.40 no.2
    • /
    • pp.138-143
    • /
    • 2004
  • This experimental paper deals with the performance of tanks that are turned the active A.R.T(Anti-Rolling Tank) when the fluid transfers from wing tank to the opposite tank by the power developed by the automatic control system (INTERING Stabilizer), which was installed in the fishery training ship T/S. A - RA (G/T:990 tons) of Cheju National University. In this paper, the author has tested the performance of INTERING Stabilizer for the signals obtained by the inclinometer in irregular waves and compared with the results obtained in passive mode operation at stop and at various ship speeds. The performances of the system were confirmed the results as follows through the tests: 1. The average amplitude and significant roll (${\pi}$1/3) of the passive and active mode operations in the condition of stoped engine and underway were obtained 8.30$^{\circ}$, 4.37$^{\circ}$, 8.30$^{\circ}$, 4.37$^{\circ}$, and 5.01$^{\circ}$, 4.36$^{\circ}$, 5.50$^{\circ}$, 5.10$^{\circ}$, respectively. 2. The rates of performance of active mode operations were carried out during a sea trial in the condition of stop engine and underway resulted in 47.5%, 12.7%, respectively, therefore the active mode operation estimated to be improved more than passive mode operation. 3. Active - A.R.T by INTERING Stabilizer didn't affect the amplitude of pitching.