Selection of organic Rankine cycle working fluid based on unit-heat-exchange-area net power  

作　　者：郭美茹 朱启的 孙志强 周天 周孑民 

机构地区：[1]School of Energy Science and Engineering, Central South University [2]Hunan Key Laboratory of Energy Conservation in Process Industry (Central South University)

出　　处：《Journal of Central South University》2015年第4期1548-1553,共6页中南大学学报（英文版）

基　　金：Projects(U0937604,50876116)supported by the National Natural Science Foundation of China;Projects(2010QZZD0107,2014zzts192)supported by the Fundamental Research Funds for the Central Universities of China

摘　　要：To improve energy conversion efficiency, optimization of the working fluids in organic Rankine cycles(ORCs) was explored in the range of low-temperature heat sources. The concept of unit-heat-exchange-area(UHEA) net power, embodying the cost/performance ratio of an ORC system, was proposed as a new indicator to judge the suitability of ORC working fluids on a given condition. The heat exchange area was computed by an improved evaporator model without fixing the minimum temperature difference between working fluid and hot fluid, and the flow pattern transition during heat exchange was also taken into account. The maximum UHEA net powers obtained show that dry organic fluids are more suitable for ORCs than wet organic fluids to recover low-temperature heat. The organic fluid 1-butene is recommended if the inlet temperature of hot fluid is 353.15-363.15 K or443.15-453.15 K, heptane is more suitable at 373.15-423.15 K, and R245 ca is a good option at 483.15-503.15 K.To improve energy conversion efficiency, optimization of the working fluids in organic Rankine cycles（ORCs） was explored in the range of low-temperature heat sources. The concept of unit-heat-exchange-area（UHEA） net power, embodying the cost/performance ratio of an ORC system, was proposed as a new indicator to judge the suitability of ORC working fluids on a given condition. The heat exchange area was computed by an improved evaporator model without fixing the minimum temperature difference between working fluid and hot fluid, and the flow pattern transition during heat exchange was also taken into account. The maximum UHEA net powers obtained show that dry organic fluids are more suitable for ORCs than wet organic fluids to recover low-temperature heat. The organic fluid 1-butene is recommended if the inlet temperature of hot fluid is 353.15-363.15 K or443.15-453.15 K, heptane is more suitable at 373.15-423.15 K, and R245 ca is a good option at 483.15-503.15 K.

关 键 词：organic Rankine cycle（ORC） working fluid selection net power heat exchange area 

分 类 号：TK124[动力工程及工程热物理—工程热物理]