The Optimal Evaporation Temperature of Subcritical ORC Based on Second Law Efficiency for Waste Heat Recovery
The subcritical Organic Rankine Cycle (ORC) with 28 working fluids for waste heat recovery is discussed in this paper. The effects of the temperature of the waste heat, the critical temperature of working fluids and the pinch temperature difference in the evaporator on the optimal evaporation temper...
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2012-03-01
|
| Series: | Entropy |
| Subjects: | |
| Online Access: | http://www.mdpi.com/1099-4300/14/3/491/ |
| _version_ | 1811264010524295168 |
|---|---|
| author | Xiaoxiao Xu Hong Gao Chao He Chao Liu Jinliang Xu |
| author_facet | Xiaoxiao Xu Hong Gao Chao He Chao Liu Jinliang Xu |
| author_sort | Xiaoxiao Xu |
| collection | DOAJ |
| description | The subcritical Organic Rankine Cycle (ORC) with 28 working fluids for waste heat recovery is discussed in this paper. The effects of the temperature of the waste heat, the critical temperature of working fluids and the pinch temperature difference in the evaporator on the optimal evaporation temperature (OET) of the ORC have been investigated. The second law efficiency of the system is regarded as the objective function and the evaporation temperature is optimized by using the quadratic approximations method. The results show that the OET will appear for the temperature ranges investigated when the critical temperatures of working fluids are lower than the waste heat temperatures by 18 ± 5 K under the pinch temperature difference of 5 K in the evaporator. Additionally, the ORC always exhibits the OET when the pinch temperature difference in the evaporator is raised under the fixed waste heat temperature. The maximum second law efficiency will decrease with the increase of pinch temperature difference in the evaporator. |
| first_indexed | 2024-04-12T19:55:25Z |
| format | Article |
| id | doaj.art-3fd343e7d75549598ad37b32fe616989 |
| institution | Directory Open Access Journal |
| issn | 1099-4300 |
| language | English |
| last_indexed | 2024-04-12T19:55:25Z |
| publishDate | 2012-03-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Entropy |
| spelling | doaj.art-3fd343e7d75549598ad37b32fe6169892022-12-22T03:18:41ZengMDPI AGEntropy1099-43002012-03-0114349150410.3390/e14030491The Optimal Evaporation Temperature of Subcritical ORC Based on Second Law Efficiency for Waste Heat RecoveryXiaoxiao XuHong GaoChao HeChao LiuJinliang XuThe subcritical Organic Rankine Cycle (ORC) with 28 working fluids for waste heat recovery is discussed in this paper. The effects of the temperature of the waste heat, the critical temperature of working fluids and the pinch temperature difference in the evaporator on the optimal evaporation temperature (OET) of the ORC have been investigated. The second law efficiency of the system is regarded as the objective function and the evaporation temperature is optimized by using the quadratic approximations method. The results show that the OET will appear for the temperature ranges investigated when the critical temperatures of working fluids are lower than the waste heat temperatures by 18 ± 5 K under the pinch temperature difference of 5 K in the evaporator. Additionally, the ORC always exhibits the OET when the pinch temperature difference in the evaporator is raised under the fixed waste heat temperature. The maximum second law efficiency will decrease with the increase of pinch temperature difference in the evaporator.http://www.mdpi.com/1099-4300/14/3/491/organic Rankine cycleOETsecond law efficiencywaste heat temperaturepinch temperature differencewaste heat recovery |
| spellingShingle | Xiaoxiao Xu Hong Gao Chao He Chao Liu Jinliang Xu The Optimal Evaporation Temperature of Subcritical ORC Based on Second Law Efficiency for Waste Heat Recovery Entropy organic Rankine cycle OET second law efficiency waste heat temperature pinch temperature difference waste heat recovery |
| title | The Optimal Evaporation Temperature of Subcritical ORC Based on Second Law Efficiency for Waste Heat Recovery |
| title_full | The Optimal Evaporation Temperature of Subcritical ORC Based on Second Law Efficiency for Waste Heat Recovery |
| title_fullStr | The Optimal Evaporation Temperature of Subcritical ORC Based on Second Law Efficiency for Waste Heat Recovery |
| title_full_unstemmed | The Optimal Evaporation Temperature of Subcritical ORC Based on Second Law Efficiency for Waste Heat Recovery |
| title_short | The Optimal Evaporation Temperature of Subcritical ORC Based on Second Law Efficiency for Waste Heat Recovery |
| title_sort | optimal evaporation temperature of subcritical orc based on second law efficiency for waste heat recovery |
| topic | organic Rankine cycle OET second law efficiency waste heat temperature pinch temperature difference waste heat recovery |
| url | http://www.mdpi.com/1099-4300/14/3/491/ |
| work_keys_str_mv | AT xiaoxiaoxu theoptimalevaporationtemperatureofsubcriticalorcbasedonsecondlawefficiencyforwasteheatrecovery AT honggao theoptimalevaporationtemperatureofsubcriticalorcbasedonsecondlawefficiencyforwasteheatrecovery AT chaohe theoptimalevaporationtemperatureofsubcriticalorcbasedonsecondlawefficiencyforwasteheatrecovery AT chaoliu theoptimalevaporationtemperatureofsubcriticalorcbasedonsecondlawefficiencyforwasteheatrecovery AT jinliangxu theoptimalevaporationtemperatureofsubcriticalorcbasedonsecondlawefficiencyforwasteheatrecovery AT xiaoxiaoxu optimalevaporationtemperatureofsubcriticalorcbasedonsecondlawefficiencyforwasteheatrecovery AT honggao optimalevaporationtemperatureofsubcriticalorcbasedonsecondlawefficiencyforwasteheatrecovery AT chaohe optimalevaporationtemperatureofsubcriticalorcbasedonsecondlawefficiencyforwasteheatrecovery AT chaoliu optimalevaporationtemperatureofsubcriticalorcbasedonsecondlawefficiencyforwasteheatrecovery AT jinliangxu optimalevaporationtemperatureofsubcriticalorcbasedonsecondlawefficiencyforwasteheatrecovery |