Objectives  Thermodynamic nonequilibrium characteristics of marine steam accumulator during the process of energy charge is studied in this paper.

  Methods  According to operating conditions of a marine steam accumulator, the thermodynamic nonequilibrium law of marine steam accumulator during the process of energy charge is analyzed. Key parameters of the thermodynamic nonequilibrium characteristics such as pressure, temperature, turbulent kinetic energy and water filling coefficient are obtained. The mechanism of thermodynamic nonequilibrium in steam accumulator energy charge process is revealed based on the theory of nonequilibrium thermodynamics.

  Results  The results of the study show that steam accumulator shows a significant thermodynamic nonequilibrium process during the energy charge, which is caused by phase change relaxation and thermal inertia effect of steam and water in steam accumulator. Meanwhile, the temperature response in the accumulator lagged behind the pressure response and flow transitions of turbulent kinetic energy and turbulent dissipation rate are occurred.

  Conclusions  Therefore, these research results can provide reference for the optimization design of energy charge process of the actual marine steam accumulator.