天然气驱动VM循环热泵的热力学分析

THERMODYNAMIC ANALYSIS FOR NATURAL GAS DRIVEN VUILLEUMIER CYCLE HEAT PUMP

天然气驱动VM循环热泵采用天然气作为高品位驱动能源,无工质替代问题,对缓解夏季电力供应紧张和环境污染等问题具有重要的意义。本文建立了热力学模型,分析结果表明:对于理想循环,热泵性能系数随着高温热源和低温热源温度的升高而增大,随着中间温度热源温度的升高而减小,并且热源温度变化对性能系数的影响从大到小依次为低温热源、中间温度热源和高温热源;对于理论循环,在运行区间,随着转速的增加,制冷量增大,而性能系数降低,但制冷量和性能系数都随着平均压力的增加而增大。

Natural gas driven vuilleumier cycle heat pump adopts natural gas as the high grade driven energy, it has no refrigerants phase out, and will be benefit to avoid the summer short-term electric peak load and solve the problems of environmental pollution. The thermodynamics models are established in this paper, results show that for the ideal natural gas driven vuilleumier cycle heat pump, the coefficient of performance （COP） for the heat pump is augment as the increased temperature of the high and the low temperature heat source, but it diminishes as increased temperature of the intermediate heat source. The influence of the temperature of heat sources on COP is the low, the intermediate and the high temperature heat source in turn. For theoretical cycle, in the range of its operation, the increment of the rotational speed will augment the cooling capacity, but will decrease the COP of the system. The elevation of pressure will both increase the cooling capacity and the system performance.