Experimental Analysis And Calculation Of Slamming Loads Of Ships With Long Forecastle

Long forecastle ships have larger internal using space and smaller deck wave than normal ships, Long forecastle hull form is usually adopted by Marine engineering ship and military vessels. However, Company with these advantages, serious slamming phenomenon occurring due to the large obvious bow flare area. To ensure the safety of local structure in the bow flare area, slamming structural strength assessment must be made in this area in the structural design stage. While, there is not a special forecasting method for the structural strength assessment of slamming loads for the long forecastle ship. So, By Studying existing slamming calculation methods and model experimental methods, propose a suitable for engineering , reliable in accuracy slamming design loads determining method for the long forecastle ship, the main research contents include the following aspects:1) Study the direct calculation for slamming loads, and use it to calculate the slamming loads of a certain long forecastle ship, analyze the slamming loads distribution characteristics.2) Design and Carry out a self-propelled navigation slamming loads tests with whole ship model, and a free falling slamming loads tests with hull section model for the certain long forecastle ship. Compare the results of tests, find the space distribution characteristics and changing rules with height and length of wave as well as sailing speed.3) Study the relevant slamming rules of the various classification societies, and use it to calculate the slamming loads of a certain long forecastle ship. Make comparisons of calculation results with different methods, Analyze the slamming distribution characteristics,and the advantages and disadvantages of each method. Propose a slamming design loads determining method for the long forecastle ship.4) Study on an equivalent static method for the assessment of the impact strength. The impact pressure of ship is calculated with the proposed method .With the correction of the three dimensional effect, the dynamic load effect and the simultaneous load effect, the impact pressure is converted to static pressure, the strength of long forecastle is evaluated.