Concentrating on the problem of massive energy loss in the compressor, expansion valve, and the other components present in the high-temperature heat pump system under extensive temperature lift, the dual-flash compound circulation system is proposed and the thermodynamic model of the dual-flash compound circulation system was established. The article combines the multivariate simulated annealing algorithm, utilizes the system COP as the optimization goal, and completes the calculation of the thermodynamic parameters in the steady-state of the system that is based on satisfying the conditions of the system process. Using R245fa as the refrigerant, the condensation temperature is set within the range of 110°C–140°C for the model calculation. The results show that, compared to the traditional two-stage compression system under the same environment, the COP of the dual-flash compound circulation system can be increased up to 5.71%–12.13%, and the exergy efficiency can be increased by 5.11%–10.71%, respectively. Besides, steam production per unit refrigerant is also increased by 3.79%–5.14%. Finally, the feasibility of the theoretical model is verified by simulation, and it is concluded that the dual-flash compound circulation system has better steam production performance at the extensive temperature lift and the elevated condensation temperature.

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With the rise in the widespread application of high-temperature heat pump (HTHP) systems, the system temperature across the large volume, high condensing temperature, and sink unbalanced proportion of heat supply, and other characteristics of the HTHP system need to be optimized as the primary solution. To improve the thermodynamic performance of the system at high temperatures across the process, the effects of the intermediate cooling structure circulation mode and hierarchical heating on the HTHP system were analyzed in this work. Furthermore, the HTHP system was optimized by adjusting the appropriate diversion coefficients in order to improve its coefficient of performance (COP). The optimum value of COP and the corresponding coefficients of diversion for the different process requirements were calculated using R245fa as the refrigerant and perturbing the coefficients of diversion in combination with a simulated annealing algorithm. When the condensing temperature was between 120–140 °C, the COP of the optimized system was observed to be 15.93–20.48% higher than that of the traditional two-stage compression system, and the system was found to exhibit a significant unit heat production and refrigeration capacity.

The thermodynamic performance of a high‐temperature heat pump steam (HTHPS) system is determined mainly by its different cycle configurations. The present study involves improving the thermodynamic performance of a quasi‐two‐stage vapor compression high‐temperature heat pump based on a front internal heat exchanger (IHX) cycle and a rear, and analyzing the influence of an IHX. The present study establishes thermodynamic models for front reheating structure (FRS) and rear reheating structure (RRS) models on the basis of conservation of mass and energy. The system is compared to the traditional quasi‐two‐stage compression cycle system in terms of thermodynamic parameters. The results demonstrated that the RRS system exhibits an increase of 4.87% in the coefficient of performance when the exhaust superheats is maintained under 5 K. With an increase in the condensation temperature, the required mass flow of the refrigerant in the traditional system is 9.94–12.36% higher compared to the RRS system, the power consumption of the compressor is increased by 3.9–5.6%, and the steam output per unit refrigerant is decreased by 1.04–5.07%. Furthermore, the Aspen Plus simulation verifies that the reason for the change in the exhaust superheats is the different pressure ratios in the theoretical calculation.