tailieunhanh - Lesson 1-Principal Dimensions

Giáo trình ngôn ngữ Anh-Việt. về các kiến thức công nghệ đóng tàu. Tài liệu học tiếng Anh dành cho sinh viên chuyên ngành kỹ thuật tàu thủy. | Lesson 1-Principal Dimensions If you turn up a technical specification which is regarded as the code of shipbuilding you will always find that Main Group 1 in the index is Ship General. Normally speaking contents under Ship General will in spite of some slight differences among individual specifications include general description materials dimensions and tonnage stability classification drawings supervision tests and trials delivery etc. In this little passage however we would like to concentrate on the sea-keeping performances only. Different seakeeping performances of vessels have much to do with principal dimensions and ship forms. So it is quite necessary to discuss the principal dimensions and geometrical characteristics of hull at the very beginning. 1. Elements of Geometrical Characteristics Three Cross Sections of Hull Vertical to One Another The middle longitudinal cross section-a longitudinal vertical plane along the centreline of ship length and a symmetrical plane between port and starboard. The midship transversal cross section-a transversal vertical plane at midship. The design water plane-a horizontal plane through design waterline. . Principal Dimensions The length overall LOA -the max. horizontal distance from bow to stern. The length B P LBP --the horizontal distance between the two perpendiculars i. e. stem and stern. The length W L LWL -the length of design waterline or the length of full-load waterline. The breadth moulded B -the max. breadth at design waterline. The depth moulded D. H -the vertical height from the upper surface of keel to the surface of upper deck within the midship transversal cross section. Draft draught d -the vertical height from the upper surface of keel to design waterline. Freeboard F -equal to the depth moulded minus draft. Fig. 1. 1 Principal Dimensions Coefficients of Ship Form There are mainly four coefficients for ship form. They are the design water plane coefficient the midship transversal cross .