수치해석을 이용한 근해안강망 어구 모델링과 거동분석

Abstract

The Korean stow net is a fishing method that utilizes the changing direction of the net entrance with the tidal current. The actual CPUE using this method is considerably higher owing to higher production and lower oil consumption and manpower per ship than those of other fishing methods. Stow net fisheries also account for a considerable portion of the annual Korean fishing production, making them a major contributor to the coastal fishing industry. This study attempted to obtain basic data from the recent offshore stow net fisheries to improve the gear by analyzing the dynamic behavior of the nets affected by current speed and direction using computer simulations. A numerical calculation was performed at a current speed of 0.5 kn between 2.5 kn at each 0.5 kn. The time taken for the gear opening was the longest from 0.5 kn at 1,500 s and the shortest from 2.5 kn at 450 s. In all cases, when net deployment occurred, the net width and tension gradually decreased as the current speed decreased. However, the net height tended to increase when the current speed decreased. During the net rotation, the net height was maintained for each case. The net width and tension fluctuated, but the regularity was very low. In this study, the calculated simulation data showed that when the current speed was decreased, the opening efficiency decreased. The opening efficiency is related to the catching efficiency; therefore, it is necessary to improve the gear to enhance its opening efficiency.