Objectives   Marine steam accumulator can provide impetus for large steam power equipment of ships, it is necessary to study the thermodynamic non-equilibrium characteristics under the condition of large energy release disturbance in order to guarantee its safety and stable operation.

  Methods   A model of large energy release disturbance considering thermodynamic non-equilibrium is established according to the characteristics of the marine steam accumulator. The accuracy of the thermodynamic non-equilibrium energy release model is verified by comparing the simulation data with the experimental data. The thermodynamic non-equilibrium characteristics of marine steam accumulator with large discharge disturbance are studied. The key parameters of non-equilibrium fraction, non-equilibrium pressure difference and non-equilibrium temperature difference characterizing the thermodynamic non-equilibrium process is revealed by numerical simulation.

  Results   The calculation results show that the change of water temperature is behind the pressure response because of thermal inertia of water space during the process of energy discharge marine steam accumulator. This made that the spontaneous flash evaporation happen in the accumulator. The mass flow, pressure and temperature of steam accumulator energy discharge showed a strong thermodynamic non-equilibrium state.

  Conclusions  These research results can provide data reference for the optimization design of the actual marine steam accumulator.