Optimization of mixed working fluids for a novel trigeneration system based on organic Rankine cycle installed with heat pumps
Optimization of mixed working fluids for a novel trigeneration system based on organic Rankine cycle installed with heat pumps
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DOI：
10.1016/j.applthermaleng.2015.10.145
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发表时间：
2016-02
影响因子：
6.4
通讯作者：
Zishen Li;Weiyi Li;Bo Xu
中科院分区：
文献类型：
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作者：
Zishen Li;Weiyi Li;Bo Xu
提出了一种新型的冷热电三联供朗肯循环系统。首先讨论了使用非共沸混合物的CCHP-ORC系统，这项工作的重点是选择最佳的非共沸混合物，并确定组分浓度，给出了一个更好的性能。建立了理想工况下的系统模型。热源为95 ℃的地热水，质量流量为40 t/h。传热流体被加热到45 °C用于在环境温度为-5 °C的情况下加热，并且制冷流体被冷却到0 °C，环境温度为35 °C。本文分析了20种非共沸混合物。在引射系数为0.2的条件下，计算了蒸发温度变化时的净输出功率、制热量、制冷量、性能系数（COP）、经济热效率和火用效率等评价指标。将喷射系数和蒸发温度作为自变量进行了分析。结果表明，R141 b/R134 a、R141 b/R152 a和R123/152 a具有较高的COP和（火用）效率。通过分析优化后的三种非共沸混合工质的组分浓度，可以推断出干湿混合工质更适合于该系统。如果非共沸混合物由较高比例的湿工作流体和较低比例的干工作流体制成，则系统产生较高的能量输出。
A novel combined cooling, heating and powerorganic Rankine cycle (CCHP–ORC) system installed with heat pumps is presented in this paper. The CCHP–ORC system using zeotropic mixtures is first discussed, and this work is focused on selecting optimal zeotropic mixtures and determining the component concentration that gives a better performance. A system model under an idealized operating condition was built. The heat source is geothermal water whose temperature is 95 °C, and the mass flow is 40 t/h. The heat transfer fluid is heated to 45 °C for heating with the ambient temperature of −5 °C, and the refrigerating fluid is cooled to 0 °C with the ambient temperature of 35 °C. In this paper, 20 zeotropic mixtures were analyzed. The evaluation index net output power, heating capacity, refrigerating capacity, coefficient of performance (COP), economic thermal efficiency and exergy efficiency were calculated with the changing evaporation temperature under the condition of ejector coefficient 0.2. The ejector coefficient and evaporation temperature had been analyzed as independent variables. The results showed that R141b/R134a, R141b/R152a and R123/152a have a higher COP and exergy efficiency than others. By analyzing the component concentration of the optimized three kinds of zeotropic mixtures, it can be inferred that a mixture of dry and wet working fluids is more suitable for the system. The system gives rise to higher energy output if zeotropic mixtures are made of a higher proportion of wet working fluid and a lower proportion of dry working fluid.