为了合理利用太阳能,增强制冷系统的季节适应性,提出一种中温太阳能驱动的氨水吸收式制冷系统。以抛物面槽式太阳能集热器(parabolic trough solar collector,PTSC)驱动的氨水单效吸收式制冷系统为对象,根据热力学定律和能量平衡方程,...为了合理利用太阳能,增强制冷系统的季节适应性,提出一种中温太阳能驱动的氨水吸收式制冷系统。以抛物面槽式太阳能集热器(parabolic trough solar collector,PTSC)驱动的氨水单效吸收式制冷系统为对象,根据热力学定律和能量平衡方程,在工程求解器(engineering equation solver,EES)下,分别建立太阳能集热器模型和制冷系统模型,并对系统的关键参数进行计算。从制冷量、精馏热和系统能效比(COP)三方面分析了系统高压、系统低压、蒸发器出口温度和精馏器出口质量分数对系统的影响。结果表明:制冷量随系统低压的升高而降低;精馏热及COP随系统低压的升高而增加;蒸发器的出口温度升高时,制冷量和COP均有增加;当精馏器出口氨的质量分数为0.977~0.999,COP在氨水质量分数为0.992时出现最大值。研究结果为太阳能驱动单级吸收式制冷循环的可行性提供了理论依据。展开更多
A novel power and cooling cogeneration system which combines a supercritical CO_(2) recompression cycle(SCRC), an ammonia-water absorption refrigeration cycle(AARC) and a Kalina cycle(KC) is proposed and investigated ...A novel power and cooling cogeneration system which combines a supercritical CO_(2) recompression cycle(SCRC), an ammonia-water absorption refrigeration cycle(AARC) and a Kalina cycle(KC) is proposed and investigated for the recovery of medium-temperature waste heat. The system is based on energy cascade utilization, and the waste heat can be fully converted through the simultaneous operation of the three sub-cycles. A steady-state mathematical model is built for further performance study of the proposed system. When the exhaust temperature is 505℃, it is shown that under designed conditions the thermal efficiency and exergy efficiency reach 30.74% and 61.55%, respectively. The exergy analysis results show that the main exergy destruction is concentrated in the heat recovery vapor generator(HRVG). Parametric study shows that the compressor inlet pressure, the SCRC pressure ratio, the main compressor and the turbine I inlet temperature, and the AARC generator pressure have significant effects on thermodynamic and economic performance of the combined system. The findings in this study could provide guidance for system design to achieve an efficient utilization of medium-temperature waste heat(e.g., exhaust heat from gas turbine, high-temperature fuel cells and internal combustion engine).展开更多
基金supported by the Shandong Provincial Natural Science Foundation of China(No.ZR2019MEE045)the National Natural Science Foundation of China(No.51776203)the Key Project of National Natural Science Foundation of China(No.61733010)。
文摘A novel power and cooling cogeneration system which combines a supercritical CO_(2) recompression cycle(SCRC), an ammonia-water absorption refrigeration cycle(AARC) and a Kalina cycle(KC) is proposed and investigated for the recovery of medium-temperature waste heat. The system is based on energy cascade utilization, and the waste heat can be fully converted through the simultaneous operation of the three sub-cycles. A steady-state mathematical model is built for further performance study of the proposed system. When the exhaust temperature is 505℃, it is shown that under designed conditions the thermal efficiency and exergy efficiency reach 30.74% and 61.55%, respectively. The exergy analysis results show that the main exergy destruction is concentrated in the heat recovery vapor generator(HRVG). Parametric study shows that the compressor inlet pressure, the SCRC pressure ratio, the main compressor and the turbine I inlet temperature, and the AARC generator pressure have significant effects on thermodynamic and economic performance of the combined system. The findings in this study could provide guidance for system design to achieve an efficient utilization of medium-temperature waste heat(e.g., exhaust heat from gas turbine, high-temperature fuel cells and internal combustion engine).
