연구조사선 제라호의 횡동요 특성에 관한 연구

Abstract

By modeling research ship M/V JERAHO from jeju National University, the test ships rolling characteristics were analyzed in wind force level 3 and 5 sea states by the ship's simulator. If you look at the analysis of the longitudinal and horizontal forces on wind and fluid force, by component wave, when there are and when there are not. Overall, the larger the wind force scale was, the greater the force received in the winds, the more laterally the power received, and the lesser the force received in the direction of the longitudinal, the more likely it was to decrease from the head sea to the follow sea. On the other hand, in the wind force scale 5 is lowest in the beam sea, largest in the head sea. longitudinal fluid force was similar to above result. And lateral forces were shown to be large at both wind force scale 3 and 5, with the wind and fluid forces having the same tendency to be proportional to those that would not account for the flow rates at all. Ship rolling statistical analysis showed small changes in the effects of current on the whole but big changes in terms of wind force scales. It was then shown that the mean and significance of the rolling angles were mostly large for the competitors and for the waves, with the mean values being equally distributed. On the other hand, the rolling angle was not large and the dispersion value was small in the head sea and the follow sea. In particular, the follow sea showed a tendency to decrease in rolling angles compared to the head sea and the beam sea. The analysis of the natural cycles for ship rolling at wind force scale 3 and 5 by component wave revealed that the incident wave pattern variation most often occurred at wind force scale 3, with no tidal current remaining at all, and at current speed of 1 and 2 kts. most slow incident wave's priod was 7.792sec on the 1kt current speed. Overall, the longer the period was left to the follow sea, and the faster the current speed was slow. And I could see that the wind force 5 had the same tendency as in class 3, and the follow sea had a very slow cycle of more than 12.00sec. The change in GM according to the incident wave shape and velocity was decreased by the force of the wind system, resulting in a decrease in the incident wave (head, bow, beam, quarter, follow), and the rapid change in the incident wave toward the stern. In the initial slope test of the m/v jeraho, GM=0.851m and the experimental result values are compared to the additional seeding in wind force scale 5, ship speed 12.0kn't. And with the same ship speed and current speed of 1kn't, the follow sea and the beam sea in the wind force scale 5. In addition, it is found that when sailing with the ship speed and current speed of 2 kn't, the wind force scale 5 receives the beam sea, the quarter sea, and the follow sea, GM is lower than before. Therefore, it is deemed necessary to pay extra attention to the m/v jeraho so that they do not receive the quarter sea even though they do not conduct or navigate in general during wind scale 5. Based on these data, the more detailed data of the vessel were entered and many ships were modelled to help with the results of the navigation and the is presented in advance.