六枚仕立底曳網の研究―2 : 六枚仕立と四枚仕立底曳網の力学的比較

After analyzing theoretically the mechanical characteristics of a sixseam trawl and a four-seam trawl, a series of experiments of both models was conducted in a ferro circulating water tank to compare their relative merits. The comparison of their important performance such as the spread of wings, elevation of headline and total resistance of nets was carried out theoretically as well as experimentally. Since no remarkable difference of the spread of wings of both trawls could be noted even though the wing of four-seam trawl was longer than that of the six-seam trawl, the conclusion could be drawn that the greater total resistance of the six-seam trawl nets than that of the four-seam trawl nets is much affected by higher elevation of its headline

西日本小型底曳網の力学的研究

The mechanical characteristics of a four-seam trawl net being used in the west Japan district was studied on the basis of its construction. The authors, in this report, watched especially on the wing length of the net. It was found that when the transversal distance between the danlenos exceeds the length of 13.6 cm in the model net and 408 cm in the practical net, the force acting on the net becomes smaller as the wing becomes longer at the towing speeds that are given in the practical fishing

流れの中にある物体の抗力測定の一方法

In order to make an accurate measurement of the drag force of the immersed body against the stream, a simple device was devised by attaching the strain gauge on a steel plate. It has become clear that direct measurement of the drag force of the immersed body by use of the device is feasible, and also the value obtained by indirect measurement which has been employed in this laboratory must be revised by approximately 10%

六枚仕立底曳網の研究―2 : 六枚仕立と四枚仕立底曳網の力学的比較

After analyzing theoretically the mechanical characteristics of a sixseam trawl and a four-seam trawl, a series of experiments of both models was conducted in a ferro circulating water tank to compare their relative merits. The comparison of their important performance such as the spread of wings, elevation of headline and total resistance of nets was carried out theoretically as well as experimentally. Since no remarkable difference of the spread of wings of both trawls could be noted even though the wing of four-seam trawl was longer than that of the six-seam trawl, the conclusion could be drawn that the greater total resistance of the six-seam trawl nets than that of the four-seam trawl nets is much affected by higher elevation of its headline