Development of Ship-borne Type Directional Wave Recorder

1995 Fiscal Year Final Research Report Summary

• Project/Area Number: 05555270
• Research Category: Grant-in-Aid for Developmental Scientific Research (B)
• Allocation Type: Single-year Grants
• Research Field: 海洋工学
• Research Institution: YOKOHAMA NATIONAL UNIVERSITY,Faculty of Engineering
• Principal Investigator: HIRAYAMA Tsugukiyo Yokohama National University ; Faculty of Engineering Professor, 工学部, 教授 (00018061)
• Co-Investigator(Kenkyū-buntansha): UENO Seiya Yokohama National University ; Faculty of Engineering Associate Professor, 工学部, 助教授 (60203460) ; MA Ning Yokohama National University ; Faculty of Engineering Associate Professor, 工学部, 助教授 (30251755)
• Project Period (FY): 1993 – 1995
• Keywords: DIRECTIONAL SPECTRUM WAVE / WAVE RECORDER / SHIP BORNE TYPE / SHIP MOTION

Research Abstract

Wave data including wind wave and swll is very important for the design or operation of ships or ocean structures in deep sea. Until now those data were obtained through the obsevations by manual on deck. Manual method is not so accurate and difficult in the dark at nights.
So automatical measurement was strongly desired.
This reseach was devoted to the development of the estimation of encountered directional wave spectrum from responses of a running ship. Not only motions but also relative wave heights were measured and directional spectrum wave was estimated by the method of so called MLM.At the same time one to three correspondence problem between encountered frequency and wave length were resolved by applying MLM . These methods were confirmed by model experiments in a towing tank and by full-scale measurements.
Finally the base of an automatically estimating method was established.