Prediction of Motion of a Semi-submersible

Abstract

The oil/gas production due to their growing demand in the world has necessitated the exploration of new areas especially in deep water. For that purpose various types of offshore structures are used for exploration of oil and gas. Through research it has been found that semisubmersibles have less motions in deep water compared to others structures. Bangladesh is rich in gas and oil which has not been explored yet and also expected to a significant amount of minerals in this area. Recently Bangladesh has established its sovereign rights on more than 118,813 square kilometer of territorial sea, 200 nautical miles (NM) of exclusive economic zone. This area is in deep water zone and there is no alternative of offshore floating structures. In this deep sea zone, structures encountered severe motions. Generally minerals are found in deep sea where motions are severe. However general floating structures are not so stable to tolerate such motions. So more stable floating structures are required for the purpose of gas and oil exploration in deep sea region. Semi submersibles are designed with good stability; a study on motions of semi submersibles will be beneficiary for the exploration of oil gas in this deep sea region. In this study the motions computations of a semisubmersible have been carried out by the “HydorStar” developed by Bureau Veritas and the results have been compared with published experimental results.