タグボート推進器後流による曳引力減少に関する一検討 : 深水域の模型実験

概要

論文の詳細を見る
We have well known that the towing ability of a tugboat decreases because of a reaction of the jet stream caused by tugboat propeller, which acts on the ship hull of a VLCC. However at present, this fact has not yet been taken into account in the estimation of towing force. Maybe it is the reason that the influence of the jet stream on the towing force is not examined exactly and systematically and also series data on the reduction of towing force are not shown. In this paper, the change of the towing force reduction relating to the length of towing line was studied experimentally. Model experiments were carried out by using a water-tank and a pair of ship models, namely a VLCC model and a tugboat model. And two kinds of examination conditions were selected, namely (1) the rest condition which both ship models were fixed by two dynamo-meters respectively and (2) the moving condition which the VLCC model was moved laterally by the tugboat model. We obtained following results ; (1) It could be confirmed that the towing force decreased by the jet stream of the tug boat propeller. And the efficiency of the towing force relating to the length of tug line was suggested based on series experiment. (2) The above efficiency more decreased in the moving condition which the VLCC was moved by the tugboat.
2002-09-25