نوع مقاله : مقاله پژوهشی
نویسندگان
1 دانشجوی دکتری ،گروه فنی کشاورزی، دانشکده فناوری ابوریحان،دانشکده کشاورزی و منابع طبیعی، دانشگاه تهران، تهران ایران
2 2. دانشیار گروه فنی کشاورزی-دانشکدگان کشاورزی و منابع طبیعی، دانشکده فناوری ابوریحان -دانشگاه تهران، تهران ، ایران
3 دانشگاه تهران، پردیس کشاورزی و منابع طبیعی، دانشکده فناوری ابوریحان،دانشگاه تهران،تهران، ایران
چکیده
کلیدواژه‌ها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Energy costs for greenhouses are one of the most important challenges for crop production in such environments. Predicting the thermal needs of a greenhouse is essential to improve its thermal performance, and achieving an optimal solution for predicting thermal behavior and energy management is very complex. In this study, a real rose greenhouse model in Pakdasht city was simulated using TRNSYS software. In this model, the greenhouse geometry as well as the ventilation, cooling, and heating systems were simulated according to their real counterparts. During a month, the temperature and relative humidity inside the greenhouse were measured using sensors installed at different points in the greenhouse. The simulated data were compared with the measured data collected each month. The difference between the simulation results and the measured data was calculated using the following criteria: root mean square error (RMSE), coefficient of variation of root mean square error (CV RMSE), and normalized mean bias error (NMBE). The temperature error inside the greenhouse was 3.5 °C and 12% for relative humidity. Using greenhouse simulation, the greenhouse energy balance was calculated for each month over a year, which showed that the largest energy losses in the greenhouse were related to the ventilation system and heat transfer through its walls. In addition, the orientation of the greenhouse played a significant role in its thermal performance, with orientation changing up to 5% of the solar energy received by the walls.
کلیدواژه‌ها [English]
EXTENDED ABSTRACT
The purpose of this research is to simulate the greenhouse with TRNSYS software and compare the simulation data with the experimental data of temperature and relative humidity inside the greenhouse, taking into account all the parameters affecting its thermal performance, to reduce the cooling and heating loads of the greenhouse during one year. be estimated It should also be noted that this software is able to predict thermal loads with some percentage of error compared to the actual greenhouse sample.
The studied miniature rose greenhouse is located in the Pakdasht greenhouse town with the latitude and longitude of the greenhouse location 51/51 E, 441406/35 N. The purpose of this research is to simulate the greenhouse and validate the temperature and relative humidity inside the greenhouse with the measured temperature and relative humidity during one month of the year and generalize it for the whole year. For this, the temperature and relative humidity inside the greenhouse were measured and compared with the simulated data. The geometry of the greenhouse is drawn with TRNSYS 3D Plug-in with Sketch Up along with the information given in the greenhouse plan. The interior of the greenhouse is designed with the same distribution as a real greenhouse. Each greenhouse is considered as a separate space. In TRNSYS, each space is considered a thermal zone.
The simulation greenhouse simulation diagram developed in TRNSYS is formed by several components called Types, which are configured in the Simulation Studio interface. The simulation starts at 00:00 on July 1 and ends at 00:00 on August 1, 1402, and the time interval was one hour. The building file generated by TRNBUILD was called by the Type 56 component in the TRNSYS simulation. The temperature and relative humidity of the ambient air (Pakdasht city) were simulated during one year to better understand the results. The temperature and relative humidity inside the simulated greenhouse were compared with the real data of the temperature and relative humidity of the greenhouse. Then the heat requirement of the greenhouse was investigated. Also, the energy balance for the greenhouse with the ideal cooling and heating system was also obtained so that a comparison between two types of cooling system can be made and the greenhouse can be generalized in different weather conditions of the country. Also, one of the design parameters of the greenhouse, which is its orientation, was investigated.
The energy balance of a real greenhouse with a miniature rose crop was simulated in TRNSYS software and the results of the simulation data were compared with the measured data. The errors obtained from the compared results were acceptable. The energy balance for the studied greenhouse was obtained during one year. The biggest energy loss in the greenhouse was related to the ventilation system. After the cooling system, the energy losses from the walls had the largest share of the greenhouse energy losses. The orientation of the greenhouse plays an important role in the thermal performance of the greenhouse, and its orientation should be determined according to the conditions of the greenhouse and its location.
“Conceptualization, G.R. and A.A.; methodology, G.R.; software, M.S.; validation, M.S., G.R. and A.a.; formal analysis, M.S.; investigation, G.R.; resources, A.A.; data curation, X.X.; writing—original draft preparation, M.S.; writing—review and editing, M.S.; visualization, A.A.; supervision, G.R.; project administration, G.R.; funding acquisition, M.S. All authors have read and agreed to the published version of the manuscript.”
All authors contributed equally to the conceptualization of the article and writing of the original and subsequent drafts.
The measured data from the Jafari greenhouse located in the Gulfam greenhouse town was used.
The authors would like to acknowledge the generous assistance of Mr. Jafari, the greenhouse manager, as well as the agricultural technical group.
The authors would like to thank all participants of the present study.
The authors avoided data fabrication, falsification, plagiarism, and misconduct.
The author declares no conflict of interest.
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