Research On Program System For The Longitudinal Strength Of Deck Cargo Ship Considering Deflection Based On NAPA

Deck cargo ship is self-navigated and mainly transports dry,mixed, bulk cargo on deck. This ship has open cargo deck, and unloading conveniently. However, the length depth ratio (L/D)of such ship,especially breath depth ratio (B/D) are larger than the current "standard" (with scale applicable to the scope of (B/D≤2.5) of the flat structure).Its deformation is often larger,the longitudinal strength and deflection must be given adequate attention.This article is based on NAPA software development platform, using NAPA BASIC language to develop a set of checking system about the longitudinal strength of deck cargo ship considering deflection and taking into account the deflection and the longitudinal strength check.This paper studies are as follows:(1) to establish the framework of the program system and the system flow chart.(2) the value of offset modeling based on the characteristics of NAPA-type, using parameters of the ideas, according to the existing value of the mother-ship into the hull of the type of parametric model.(3) of the simple single-span beams to complex curved hull Beams situation analysis, numerical methods and Gaussian for solving the hull beam deflection.(4) by calling the Loading Condition NAPA software modules and tables (Table) This particular form of data, the data in Table is stored, to facilitate calls between the modules to achieve the deflection calculation.Longitudinal strength of ship design process is considered one of the most important, lack of longitudinal strength can cause damage to the hull,resulting in significant loss of personnel and property. In this paper, using a deck cargo ships as the research object, the deflection of the vessel can be calculated after the deformation and shear deformation, bending moment, in order to achieve the stiffness and strength of the deck cargo checking. The system was developed for the calculation and taking into account the deflection of the hull deflection, the longitudinal strength provides a reference check.