Influence of Refrigerant Charge Amount and EEV Opening on the Performance of a Transcritical CO2 Heat Pump Water Heater
Besides compressor rotary speed and parameters of water flowing through gas cooler and evaporator, refrigerant charge amount and electronic expansion valve (EEV) opening are two important parameters that have significant effects on the performance of a transcritical CO2 heat pump system. In this stu...
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| Format: | Article |
| Language: | English |
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MDPI AG
2017-10-01
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| Series: | Energies |
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| Online Access: | https://www.mdpi.com/1996-1073/10/10/1521 |
| _version_ | 1797999142113378304 |
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| author | Ze Zhang Xiaojun Dong Zheng Ren Tianwei Lai Yu Hou |
| author_facet | Ze Zhang Xiaojun Dong Zheng Ren Tianwei Lai Yu Hou |
| author_sort | Ze Zhang |
| collection | DOAJ |
| description | Besides compressor rotary speed and parameters of water flowing through gas cooler and evaporator, refrigerant charge amount and electronic expansion valve (EEV) opening are two important parameters that have significant effects on the performance of a transcritical CO2 heat pump system. In this study, the effects of refrigerant charge amount on the performance of a transcritical CO2 heat pump water heater were investigated experimentally at different EEV openings. An optimal coefficient of performance (COP) was found that corresponded to a specific refrigerant charge and a specific EEV opening. Based on the experiment, the COP peaked at charge of 1.8 kg when EEV opening was 40% of full opening. The heating capacity and the COP increased at first, reached peaks and then decreased with increase of charge amount. The COP decreased 14.95% as the CO2 charge amount was reduced by 22.2% from the optimal charge at 50% EEV opening. As EEV opening varied from 40% to 60% at the same charge amount, the heating capacity decreased more than 30%. |
| first_indexed | 2024-04-11T10:59:53Z |
| format | Article |
| id | doaj.art-a7530b0742294d5c8d5c164052d085b6 |
| institution | Directory Open Access Journal |
| issn | 1996-1073 |
| language | English |
| last_indexed | 2024-04-11T10:59:53Z |
| publishDate | 2017-10-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Energies |
| spelling | doaj.art-a7530b0742294d5c8d5c164052d085b62022-12-22T04:28:40ZengMDPI AGEnergies1996-10732017-10-011010152110.3390/en10101521en10101521Influence of Refrigerant Charge Amount and EEV Opening on the Performance of a Transcritical CO2 Heat Pump Water HeaterZe Zhang0Xiaojun Dong1Zheng Ren2Tianwei Lai3Yu Hou4State Key Laboratory of Multiphase Flow in Power Engineering, Xi’an Jiaotong University, Xi’an 710049, ChinaState Key Laboratory of Multiphase Flow in Power Engineering, Xi’an Jiaotong University, Xi’an 710049, ChinaState Key Laboratory of Multiphase Flow in Power Engineering, Xi’an Jiaotong University, Xi’an 710049, ChinaState Key Laboratory of Multiphase Flow in Power Engineering, Xi’an Jiaotong University, Xi’an 710049, ChinaState Key Laboratory of Multiphase Flow in Power Engineering, Xi’an Jiaotong University, Xi’an 710049, ChinaBesides compressor rotary speed and parameters of water flowing through gas cooler and evaporator, refrigerant charge amount and electronic expansion valve (EEV) opening are two important parameters that have significant effects on the performance of a transcritical CO2 heat pump system. In this study, the effects of refrigerant charge amount on the performance of a transcritical CO2 heat pump water heater were investigated experimentally at different EEV openings. An optimal coefficient of performance (COP) was found that corresponded to a specific refrigerant charge and a specific EEV opening. Based on the experiment, the COP peaked at charge of 1.8 kg when EEV opening was 40% of full opening. The heating capacity and the COP increased at first, reached peaks and then decreased with increase of charge amount. The COP decreased 14.95% as the CO2 charge amount was reduced by 22.2% from the optimal charge at 50% EEV opening. As EEV opening varied from 40% to 60% at the same charge amount, the heating capacity decreased more than 30%.https://www.mdpi.com/1996-1073/10/10/1521transcritical CO2 cycleheat pumpCOPrefrigerant charge amountelectronic expansion valve opening |
| spellingShingle | Ze Zhang Xiaojun Dong Zheng Ren Tianwei Lai Yu Hou Influence of Refrigerant Charge Amount and EEV Opening on the Performance of a Transcritical CO2 Heat Pump Water Heater Energies transcritical CO2 cycle heat pump COP refrigerant charge amount electronic expansion valve opening |
| title | Influence of Refrigerant Charge Amount and EEV Opening on the Performance of a Transcritical CO2 Heat Pump Water Heater |
| title_full | Influence of Refrigerant Charge Amount and EEV Opening on the Performance of a Transcritical CO2 Heat Pump Water Heater |
| title_fullStr | Influence of Refrigerant Charge Amount and EEV Opening on the Performance of a Transcritical CO2 Heat Pump Water Heater |
| title_full_unstemmed | Influence of Refrigerant Charge Amount and EEV Opening on the Performance of a Transcritical CO2 Heat Pump Water Heater |
| title_short | Influence of Refrigerant Charge Amount and EEV Opening on the Performance of a Transcritical CO2 Heat Pump Water Heater |
| title_sort | influence of refrigerant charge amount and eev opening on the performance of a transcritical co2 heat pump water heater |
| topic | transcritical CO2 cycle heat pump COP refrigerant charge amount electronic expansion valve opening |
| url | https://www.mdpi.com/1996-1073/10/10/1521 |
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