Experimental study on estimation of wave force for seaweed breeding rope

• Published in: Nōgyō Doboku Gakkai ronbunshū Vol. 1985; no. 116; pp. 25 - 31,a1
• Main Author: Sakurai, K. (Mie Univ., Tsu (Japan). Faculty of Agriculture)
• Format: Journal Article
• Language: Japanese
• Published: The Japanese Society of Irrigation, Drainage and Rural Engineering 25.04.1985
• Subjects: ENERGIA HIDRAULICA; ENERGIE HYDRAULIQUE; EQUIPEMENT; EQUIPO; FISHERY PRODUCTION; LAMINARIA; OCEANOLOGIA; OCEANOLOGIE; OCEANOLOGY; PRODUCCION PESQUERA; PRODUCTION HALIEUTIQUE; WATER POWER
• ISSN: 0387-2335; 1884-7234
• DOI: 10.11408/jsidre1965.1985.116_25

For estimating the wave force for a rigid body such as concrete pole, concrete block etc, the method of O'brien-Morison is applicable. However, for long-flexible and floating body, we can hardly fi nd any study on such case. The wave force caused by the motion of wave particles deforms a seaweed breeding rope and the rope is tensioned not only by friction force of wave particles which moves along the rope line but also by the periodical drag force of the wave particles across the rope line. Furthermore, the shape of grown seaweed tuft on a rope is deformed and its compactness is changed due to the alternating motion of the wave particles. For a irregular and undefined body shape such as the above mentioned seaweed tuft, it is difficult to fi nd a suitable wave force estimation method. Thus, some experimental studies were conducted to ensure the wave force estimation method in a comparatively long rope for seaweed breeding. As a result of the study, the author found the relationship among the wave force, wave characteristics and the specification of seaweed breeding system. Following are the major outcomes: a. The relationship among Ad/L2, FT2/(ρL4), hd/h and H/L has been clarified as shown in Fig.7. Using Fig., the wave force F can be estimated. b. Found that F appears as a large value depending on the position of the float attached, and came up with a suitable way to arrange the float. c. Found the suitable depth to set the breeding facility by rope to avoid the large shock under the transitional motion of the rope.