Utilization of Surplus Air Thermal Energy by a Water Cycle System in a Chinese-Type Solar Greenhouse
Solar greenhouses are commonly overheated during the day, and the remaining air heat can only be dissipated through ventilation, which is a severe energy waste problem. In order to improve the energy utilization of the greenhouse, this study proposes a water cycle system using surplus air thermal en...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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MDPI AG
2024-01-01
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| Series: | Agronomy |
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| Online Access: | https://www.mdpi.com/2073-4395/14/2/270 |
| _version_ | 1797299141587501056 |
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| author | Lu Wang Yiming Li Zhouping Sun Sida Meng Tianlai Li Xingan Liu |
| author_facet | Lu Wang Yiming Li Zhouping Sun Sida Meng Tianlai Li Xingan Liu |
| author_sort | Lu Wang |
| collection | DOAJ |
| description | Solar greenhouses are commonly overheated during the day, and the remaining air heat can only be dissipated through ventilation, which is a severe energy waste problem. In order to improve the energy utilization of the greenhouse, this study proposes a water cycle system using surplus air thermal energy, which consists of an air-water heat exchanger, supply and return pipes, a submersible pump, a water tank, and an automatic control system. The proposed system stores the surplus air thermal energy in the greenhouse in the water tank. It releases it into the greenhouse using water circulation, and experimental analyses were carried out using a solar greenhouse in the Shenyang area. The effects of different air and water flow rates on the performance of the surplus air thermal energy water recycling system and the environment inside the greenhouse were analyzed by establishing a CFD model and model validation, and the average difference between the experimental data and the simulated data was 6.98%. The results show that the circulating air flow rate significantly affects the system performance and the environment inside the greenhouse. In the heat collection stage, the water circulation system with an airflow rate of 9 m/s has a minor average temperature difference in the vertical plane of the greenhouse. The water circulation system with an airflow rate of 6.0 m/s collects and releases the most significant heat. The temperature cloud between the vertical and horizontal planes is more uniform. This research provides new ideas for efficient energy use in solar greenhouses. |
| first_indexed | 2024-03-07T22:46:22Z |
| format | Article |
| id | doaj.art-2c5d3fccf06f4d598427c9d38fbb03f0 |
| institution | Directory Open Access Journal |
| issn | 2073-4395 |
| language | English |
| last_indexed | 2024-03-07T22:46:22Z |
| publishDate | 2024-01-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Agronomy |
| spelling | doaj.art-2c5d3fccf06f4d598427c9d38fbb03f02024-02-23T15:04:02ZengMDPI AGAgronomy2073-43952024-01-0114227010.3390/agronomy14020270Utilization of Surplus Air Thermal Energy by a Water Cycle System in a Chinese-Type Solar GreenhouseLu Wang0Yiming Li1Zhouping Sun2Sida Meng3Tianlai Li4Xingan Liu5College of Horticulture, Shenyang Agricultural University, No. 120 Dongling Road, Shenhe District, Shenyang 110866, ChinaNational & Local Joint Engineering Research Center of Northern Horticultural Facilities Design & Application Technology (Liaoning), No. 120 Dongling Road, Shenhe District, Shenyang 110866, ChinaCollege of Horticulture, Shenyang Agricultural University, No. 120 Dongling Road, Shenhe District, Shenyang 110866, ChinaCollege of Horticulture, Shenyang Agricultural University, No. 120 Dongling Road, Shenhe District, Shenyang 110866, ChinaCollege of Horticulture, Shenyang Agricultural University, No. 120 Dongling Road, Shenhe District, Shenyang 110866, ChinaCollege of Horticulture, Shenyang Agricultural University, No. 120 Dongling Road, Shenhe District, Shenyang 110866, ChinaSolar greenhouses are commonly overheated during the day, and the remaining air heat can only be dissipated through ventilation, which is a severe energy waste problem. In order to improve the energy utilization of the greenhouse, this study proposes a water cycle system using surplus air thermal energy, which consists of an air-water heat exchanger, supply and return pipes, a submersible pump, a water tank, and an automatic control system. The proposed system stores the surplus air thermal energy in the greenhouse in the water tank. It releases it into the greenhouse using water circulation, and experimental analyses were carried out using a solar greenhouse in the Shenyang area. The effects of different air and water flow rates on the performance of the surplus air thermal energy water recycling system and the environment inside the greenhouse were analyzed by establishing a CFD model and model validation, and the average difference between the experimental data and the simulated data was 6.98%. The results show that the circulating air flow rate significantly affects the system performance and the environment inside the greenhouse. In the heat collection stage, the water circulation system with an airflow rate of 9 m/s has a minor average temperature difference in the vertical plane of the greenhouse. The water circulation system with an airflow rate of 6.0 m/s collects and releases the most significant heat. The temperature cloud between the vertical and horizontal planes is more uniform. This research provides new ideas for efficient energy use in solar greenhouses.https://www.mdpi.com/2073-4395/14/2/270Chinese solar greenhousesurplus air thermal energywater cyclenumerical simulation |
| spellingShingle | Lu Wang Yiming Li Zhouping Sun Sida Meng Tianlai Li Xingan Liu Utilization of Surplus Air Thermal Energy by a Water Cycle System in a Chinese-Type Solar Greenhouse Agronomy Chinese solar greenhouse surplus air thermal energy water cycle numerical simulation |
| title | Utilization of Surplus Air Thermal Energy by a Water Cycle System in a Chinese-Type Solar Greenhouse |
| title_full | Utilization of Surplus Air Thermal Energy by a Water Cycle System in a Chinese-Type Solar Greenhouse |
| title_fullStr | Utilization of Surplus Air Thermal Energy by a Water Cycle System in a Chinese-Type Solar Greenhouse |
| title_full_unstemmed | Utilization of Surplus Air Thermal Energy by a Water Cycle System in a Chinese-Type Solar Greenhouse |
| title_short | Utilization of Surplus Air Thermal Energy by a Water Cycle System in a Chinese-Type Solar Greenhouse |
| title_sort | utilization of surplus air thermal energy by a water cycle system in a chinese type solar greenhouse |
| topic | Chinese solar greenhouse surplus air thermal energy water cycle numerical simulation |
| url | https://www.mdpi.com/2073-4395/14/2/270 |
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