NUMERICAL CALCULATION OF THE DYNAMIC RESPONSES OF VESSEL MAST STRUCTURE UNDER AIR EXPLOSION

Mast is defined as Grade A equipment which is essential for the safety and continued combat capability of the ship. Therefore, it is very necessary to evaluate the mast shock resistance under air explosion. However, it is very difficult to get the shock loading on the structure aroused by air explosion since it is varied with time and space. Flux-Corrected-Transport (FCT) algorithm is a high-order, monotone, preserving positive finite-difference algorithm. In this paper, a program is presented for air explosion load calculation based on FCT algorithm. Taking the coupling of air and mast into consideration, the pressure time history of each element on the surface of the mast is computed according to the program. A data file about the pressure load is written to integrate the commercial finite element software of LSDYNA. Furthermore, the dynamic responses of the mast are calculated based on LSDYNA. The capability of shock resistance under air explosion of the mast can be evaluated according to the calculation results, which can provide references for mast anti-explosion design..