Numerical analysis on shock environment in different ship regions subjected to underwater explosion

  Objectives  The shock environment of a warship in an underwater explosion is the basic input for the design and shock resistance ability evaluation of ship equipment.

  Methods  In this paper, a numerical simulation is used to analyze the shock environment in different regions of a ship, and the Second-order Doubly Asymptotic Approximation(DAA₂)is used to solve the fluid-structure interaction. First, the appropriate calculating parameters are chosen, such as damping ratio, and then a series of Single-Degree-of-Freedom(SDOF) systems are attached at various deck locations to simulate flexible equipment.

  Results  The accuracy and reliability of DAA₂ is verified by the fact that the calculated shock spectrums at classic regions perfectly match the data of the ship shock trial. The shock response of the SDOF systems under the same shock input are then calculated and transformed into the shock environment. Finally, the results of shock environments in different regions are compared.

  Conclusions  The conclusions of this paper can provide design reference data for the subsequent anti-shock design of equipment.