We designed, simulated, and analyzed a gas-fired heat-driven duplex Stirling domestic-combined heat and power system in order to alleviate the energy crisis and improve the efficiency of energy utilization. With the hot-end temperature of the Stirling engine fixed at 650℃ and the temperatures of the heat supply and the surroundings fixed at 60 ℃ and 0 ℃ , respectively, the duplex Stirling machine can achieve an output heating power of 5115W and an output electrical power of 79.2W, corresponding to a relative Carnot efficiency of 44.53%. The output characteristics and efficiency of the system are greatly affected by the hot-end temperature, the surrounding temperature and the average pressure. In addition, our calculations show that optimal performance under different working conditions can be obtained by adjusting the electrical resistance.
Keywords duplex Stirling, domestic-combined heat and power, efficiency, electrical resistance