The Influence of Internal Heat Exchanger on the Performance of Transcritical CO<sub>2</sub> Water Source Heat Pump Water Heater
The characteristics of the transcritical CO<sub>2</sub> heat pump water heater (HPWH) system are; a lower inlet hot water temperature (T<sub>i-hw</sub>) (sometimes this is lower than the water source temperature), and an outlet gas cooler temperature (T<sub>o-gc</sub...
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MDPI AG
2020-04-01
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| Series: | Energies |
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| Online Access: | https://www.mdpi.com/1996-1073/13/7/1787 |
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| author | Fan Feng Ze Zhang Xiufang Liu Changhai Liu Yu Hou |
| author_facet | Fan Feng Ze Zhang Xiufang Liu Changhai Liu Yu Hou |
| author_sort | Fan Feng |
| collection | DOAJ |
| description | The characteristics of the transcritical CO<sub>2</sub> heat pump water heater (HPWH) system are; a lower inlet hot water temperature (T<sub>i-hw</sub>) (sometimes this is lower than the water source temperature), and an outlet gas cooler temperature (T<sub>o-gc</sub>) which is affected by the T<sub>i-hw</sub> and often lower than the critical temperature. In order to study the effects of the internal heat exchanger (IHX) on the operational performance of the transcritical CO<sub>2</sub> HPWH when T<sub>o-gc</sub> is low, a transcritical CO<sub>2</sub> water source HPWH experiment platform is established to conduct experimental research and comparative analysis on the operational performance of the transcritical CO<sub>2</sub> water source HPWH, with or without IHX. It is found that, if only the coefficient of performance (COP) and heating at the optimal exhaust pressure of the transcritical CO<sub>2</sub> water source HPWH were considered, COP and the heating of the non-IHX system would be slightly higher than those of the IHX system at the lower hot water flow and water source temperature, and this increase was not obvious. At the higher hot water flow rate and water source temperature, COP and the heating of the non-IHX system were also higher than those of the IHX system, and the increase was obvious. The experiment results showed that, near the optimal exhaust pressure, the variation range of COP and heating of the IHX system is relatively small, and the system has a relatively high stability. |
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| id | doaj.art-6edfe0b451cf4170be3c485d802eb1e1 |
| institution | Directory Open Access Journal |
| issn | 1996-1073 |
| language | English |
| last_indexed | 2024-03-10T20:36:49Z |
| publishDate | 2020-04-01 |
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| record_format | Article |
| series | Energies |
| spelling | doaj.art-6edfe0b451cf4170be3c485d802eb1e12023-11-19T20:58:02ZengMDPI AGEnergies1996-10732020-04-01137178710.3390/en13071787The Influence of Internal Heat Exchanger on the Performance of Transcritical CO<sub>2</sub> Water Source Heat Pump Water HeaterFan Feng0Ze Zhang1Xiufang Liu2Changhai Liu3Yu 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, ChinaSchool of Civil Engineering, Zhengzhou University, Zhengzhou 450001, ChinaState Key Laboratory of Multiphase Flow in Power Engineering, Xi’an Jiaotong University, Xi’an 710049, ChinaThe characteristics of the transcritical CO<sub>2</sub> heat pump water heater (HPWH) system are; a lower inlet hot water temperature (T<sub>i-hw</sub>) (sometimes this is lower than the water source temperature), and an outlet gas cooler temperature (T<sub>o-gc</sub>) which is affected by the T<sub>i-hw</sub> and often lower than the critical temperature. In order to study the effects of the internal heat exchanger (IHX) on the operational performance of the transcritical CO<sub>2</sub> HPWH when T<sub>o-gc</sub> is low, a transcritical CO<sub>2</sub> water source HPWH experiment platform is established to conduct experimental research and comparative analysis on the operational performance of the transcritical CO<sub>2</sub> water source HPWH, with or without IHX. It is found that, if only the coefficient of performance (COP) and heating at the optimal exhaust pressure of the transcritical CO<sub>2</sub> water source HPWH were considered, COP and the heating of the non-IHX system would be slightly higher than those of the IHX system at the lower hot water flow and water source temperature, and this increase was not obvious. At the higher hot water flow rate and water source temperature, COP and the heating of the non-IHX system were also higher than those of the IHX system, and the increase was obvious. The experiment results showed that, near the optimal exhaust pressure, the variation range of COP and heating of the IHX system is relatively small, and the system has a relatively high stability.https://www.mdpi.com/1996-1073/13/7/1787transcritical CO<sub>2</sub>heat pump water heaterinternal heat exchanger |
| spellingShingle | Fan Feng Ze Zhang Xiufang Liu Changhai Liu Yu Hou The Influence of Internal Heat Exchanger on the Performance of Transcritical CO<sub>2</sub> Water Source Heat Pump Water Heater Energies transcritical CO<sub>2</sub> heat pump water heater internal heat exchanger |
| title | The Influence of Internal Heat Exchanger on the Performance of Transcritical CO<sub>2</sub> Water Source Heat Pump Water Heater |
| title_full | The Influence of Internal Heat Exchanger on the Performance of Transcritical CO<sub>2</sub> Water Source Heat Pump Water Heater |
| title_fullStr | The Influence of Internal Heat Exchanger on the Performance of Transcritical CO<sub>2</sub> Water Source Heat Pump Water Heater |
| title_full_unstemmed | The Influence of Internal Heat Exchanger on the Performance of Transcritical CO<sub>2</sub> Water Source Heat Pump Water Heater |
| title_short | The Influence of Internal Heat Exchanger on the Performance of Transcritical CO<sub>2</sub> Water Source Heat Pump Water Heater |
| title_sort | influence of internal heat exchanger on the performance of transcritical co sub 2 sub water source heat pump water heater |
| topic | transcritical CO<sub>2</sub> heat pump water heater internal heat exchanger |
| url | https://www.mdpi.com/1996-1073/13/7/1787 |
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