Direct integration of an organic Rankine cycle into an internal combustion engine cooling system for comprehensive and simplified waste heat recovery
Cogeneration systems based on internal combustion engines (ICE) provide decent efficiency and flexibility. In order to further improve the efficiency, organic Rankine cycle (ORC) can be used to convert high temperature (waste) heat from flue gas to electricity. There is a large amount of heat in jac...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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Elsevier
2021-11-01
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| Series: | Energy Reports |
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| Online Access: | http://www.sciencedirect.com/science/article/pii/S2352484721005540 |
| _version_ | 1818856611643392000 |
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| author | Vaclav Novotny Jan Spale David J. Szucs Hung-Yin Tsai Michal Kolovratnik |
| author_facet | Vaclav Novotny Jan Spale David J. Szucs Hung-Yin Tsai Michal Kolovratnik |
| author_sort | Vaclav Novotny |
| collection | DOAJ |
| description | Cogeneration systems based on internal combustion engines (ICE) provide decent efficiency and flexibility. In order to further improve the efficiency, organic Rankine cycle (ORC) can be used to convert high temperature (waste) heat from flue gas to electricity. There is a large amount of heat in jacket cooling at lower temperatures for which there is often no demand so it has to be rejected into the ambient. Previous systems trying to utilise this heat in the ORC cycle end up as too complex and expensive. This study introduces an innovative jacket cooling method. In the cooling system of an ICE, instead of typical water or oil-based heat transfer fluids, the working fluid of an ORC is used as the engine coolant, recovering the low-potential heat. Preheated organic fluid is then directly used in the bottoming ORC with further heat input from the flue gas. This concept allows utilising both low and high potential heat from the cooling of the ICE and from the flue gas recovery, while omitting the intermediate heat-transfer circuits commonly found in ORC waste heat recovery applications. Presented thermodynamic analysis shows a strong dependency of the ORC utilisation efficiency on cooling fluid allowed pressure in the ICE jacket and on the heat flow ratio between the coolant and the flue gas of the ICE. A baseline study with a specific 83 kWe ICE with the novel configuration provides an improvement of nearly 10 kW in comparison with 7 kW of an ORC utilising only flue gas. More general parametric analysis has shown the potential of the ORC power output improvement by more than 60% for specific ICE types and higher pressures and temperatures in the engine cooling circuit. In a cogeneration regime, these benefits in electrical power output come at the cost of a very slight decrease in overall efficiency. |
| first_indexed | 2024-12-19T08:27:15Z |
| format | Article |
| id | doaj.art-e13e25618ce44fe7bc8aa2581bdc76c9 |
| institution | Directory Open Access Journal |
| issn | 2352-4847 |
| language | English |
| last_indexed | 2024-12-19T08:27:15Z |
| publishDate | 2021-11-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Energy Reports |
| spelling | doaj.art-e13e25618ce44fe7bc8aa2581bdc76c92022-12-21T20:29:16ZengElsevierEnergy Reports2352-48472021-11-017644656Direct integration of an organic Rankine cycle into an internal combustion engine cooling system for comprehensive and simplified waste heat recoveryVaclav Novotny0Jan Spale1David J. Szucs2Hung-Yin Tsai3Michal Kolovratnik4University Centre for Energy Efficient Buildings, Czech Technical University in Prague, Trinecka 1024, Bustehrad, 27343, Czech Republic; Faculty of Mechanical Engineering, Czech Technical University in Prague, Techicka 4, Prague 6, 16607, Czech Republic; Department of Power Mechanical Engineering, National Tsing Hua University, No. 101, Kuang-Fu Road, Hsinchu, 30013, Taiwan; Corresponding author at: Faculty of Mechanical Engineering, Czech Technical University in Prague, Techicka 4, Prague 6, 16607, Czech Republic.University Centre for Energy Efficient Buildings, Czech Technical University in Prague, Trinecka 1024, Bustehrad, 27343, Czech Republic; Faculty of Mechanical Engineering, Czech Technical University in Prague, Techicka 4, Prague 6, 16607, Czech RepublicUniversity Centre for Energy Efficient Buildings, Czech Technical University in Prague, Trinecka 1024, Bustehrad, 27343, Czech RepublicDepartment of Power Mechanical Engineering, National Tsing Hua University, No. 101, Kuang-Fu Road, Hsinchu, 30013, Taiwan; Corresponding author at: Department of Power Mechanical Engineering, National Tsing Hua University, No. 101, Kuang-Fu Road, Hsinchu, 30013, Taiwan.Faculty of Mechanical Engineering, Czech Technical University in Prague, Techicka 4, Prague 6, 16607, Czech RepublicCogeneration systems based on internal combustion engines (ICE) provide decent efficiency and flexibility. In order to further improve the efficiency, organic Rankine cycle (ORC) can be used to convert high temperature (waste) heat from flue gas to electricity. There is a large amount of heat in jacket cooling at lower temperatures for which there is often no demand so it has to be rejected into the ambient. Previous systems trying to utilise this heat in the ORC cycle end up as too complex and expensive. This study introduces an innovative jacket cooling method. In the cooling system of an ICE, instead of typical water or oil-based heat transfer fluids, the working fluid of an ORC is used as the engine coolant, recovering the low-potential heat. Preheated organic fluid is then directly used in the bottoming ORC with further heat input from the flue gas. This concept allows utilising both low and high potential heat from the cooling of the ICE and from the flue gas recovery, while omitting the intermediate heat-transfer circuits commonly found in ORC waste heat recovery applications. Presented thermodynamic analysis shows a strong dependency of the ORC utilisation efficiency on cooling fluid allowed pressure in the ICE jacket and on the heat flow ratio between the coolant and the flue gas of the ICE. A baseline study with a specific 83 kWe ICE with the novel configuration provides an improvement of nearly 10 kW in comparison with 7 kW of an ORC utilising only flue gas. More general parametric analysis has shown the potential of the ORC power output improvement by more than 60% for specific ICE types and higher pressures and temperatures in the engine cooling circuit. In a cogeneration regime, these benefits in electrical power output come at the cost of a very slight decrease in overall efficiency.http://www.sciencedirect.com/science/article/pii/S2352484721005540ORCOrganic Rankine cycleWaste heat recoveryInternal combustion engineThermodynamic analysis |
| spellingShingle | Vaclav Novotny Jan Spale David J. Szucs Hung-Yin Tsai Michal Kolovratnik Direct integration of an organic Rankine cycle into an internal combustion engine cooling system for comprehensive and simplified waste heat recovery Energy Reports ORC Organic Rankine cycle Waste heat recovery Internal combustion engine Thermodynamic analysis |
| title | Direct integration of an organic Rankine cycle into an internal combustion engine cooling system for comprehensive and simplified waste heat recovery |
| title_full | Direct integration of an organic Rankine cycle into an internal combustion engine cooling system for comprehensive and simplified waste heat recovery |
| title_fullStr | Direct integration of an organic Rankine cycle into an internal combustion engine cooling system for comprehensive and simplified waste heat recovery |
| title_full_unstemmed | Direct integration of an organic Rankine cycle into an internal combustion engine cooling system for comprehensive and simplified waste heat recovery |
| title_short | Direct integration of an organic Rankine cycle into an internal combustion engine cooling system for comprehensive and simplified waste heat recovery |
| title_sort | direct integration of an organic rankine cycle into an internal combustion engine cooling system for comprehensive and simplified waste heat recovery |
| topic | ORC Organic Rankine cycle Waste heat recovery Internal combustion engine Thermodynamic analysis |
| url | http://www.sciencedirect.com/science/article/pii/S2352484721005540 |
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