Determining of some climate parameters using computational fluid dynamic technique in naturally ventilated greenhouses

Öz Aim of study was to compare the measured inner air temperature and relative humidity values with the simulated values determined with Computational Fluid Dynamics (CFD) technique in the naturally ventilated gable-roofed single glasshouses located East-West direction, having 90° window span and different growing conditions such as plant and without plants. In study, the gable roofed single glasshouses in West Mediterranean Agricultural Research Institute were chosen as material. Study area is located at the latitude of 36º 52' N and longitude of 30º 50' E. In the greenhouses selected as material, measured values were recorded every minute from 8 a.m. to 18 p.m. by using the relative humidity and air temperature meters placed in different locations. However, these values were used as average of 2 hours in calculations to reduce number of data. The Solid Works analysis software was used for CFD simulations of the greenhouses selected as material. The air temperature and relative humidity values inside the greenhouse were simulated depending on the outside ambient conditions and structural and physical properties of greenhouse. Then, the measured values were compared with the simulated values and compliance levels of these values were determined. In conclusion, the error rates of measured and simulated air temperature and relative humidity values in the greenhouse with plant were found as 4.9% and 0.0%, respectively. Additionally, the same values in the greenhouse without plant were also found as 0.0% and 5.2%, respectively. The study showed that the CFD may be used as a powerful tool for determining inner climatic factors in naturally ventilated greenhouses.

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Baudoin WO, Zabeltitz C (2002) Greenhouse Constructions for Small Scale Farmers in Tropical Regions. Acta Horticulturae 578: 171-179.

Baytorun N (1995) Greenhouses. University of Cukurova Faculty of Agriculture Publication Number 29, Adana (in Turkish).

Boulard T, Baille A (1993) A Simple Greenhouse Climate Control Model Incorporating Effects of Ventilation and Evaporative Cooling. Agricultural and Forest Meteorology 65:145-157.

Boulard T, Draoui B (1995) Natural ventilation of a greenhouse with continuous roof vents: measurements and data analysis. Journal of Agricultural Engineering Research 61: 27-36.

Campen JB, Bot GPA (2003) Determination of Greenhouse-specific Aspects of Ventilation using Three-dimensional Computational Fluid Dynamics. Biosystems Engineering 84(1): 69–77.

Haxaire R, Boulard T, Mermier M (2000) Greenhouse Natural Ventilation by Wind Forces. Acta Horticulture 534: 31-40.

Kacira M, Short H, Stowell RR (1998) A CFD Evaluation of Naturally Ventilated Multi-Span Sawtooth Greenhouses. Transactions of the ASAE 41(3): 833-836.

Kacira M, Sase S, Okushima L (2004) Effects of Side Vents and Span Numbers on Wind-Induced Natural Ventilation of a Gothic Multi-Span Greenhouse. Japan Agricultural Research Quarterly 38(4): 227-233.

Lamrani MA, Boulard T, Roy JC, Jaffrin A (2001) Airflows and Temperature Patterns Induced in a Confined Greenhouse. Journal of Agricultural Engineering Research 78(1): 75-88.

Mistriotis A, Arcidiacono C, Picuno P, Bot GPA, Scarascia-Mugnozza G (1997a) Computational Analysis of Ventilation in Greenhouses at Zero-and Low-Wind-Speeds. Agricultural and Forest Meteorology 88: 121-135.

Mistriotis A, Bot GPA, Picuno P, Scarascia-Mugnozza G (1997b) Analysis of The Efficiency of Greenhouse Ventilation using Computational Fluid Dynamics. Journal of Agricultural Engineering Research 85: 217-228.

Nara M (1979) Studies of Air Distribution in Farm Buildings. Journal of the Society of Agricultural Structures 9(2): 17-26.

Ould Khaoua SA, Bournet PE, Migeon C, Boulard T, Chasseriaux G (2006) Analysis of Greenhouse Ventilation Efficiency based on Computational Fluid Dynamics. Biosystems Engineering 95(1): 83-98.

Ozturk HH (2008) Greenhouse Climate Technique. Istanbul, Turkey: Hasad Publishing.

Papadakis G, Mermier M, Meneses JF, Boulard T (1996) Measurement and Analysis of Air Exchange Rates in a Greenhouse with Continuous Roof and Side Openings. Journal of Agricultural Engineering Research 63: 219-228.

Teitel M, Ziskind G, Liran O, Dubovsky V, Letan R (2008) Effect of Wind Direction on Greenhouse Ventilation Rate, Airflow Patterns and Temperature Distributions. Biosystems Engineering 101(3): 351-369.

Zabeltitz CV (1992) Technologies for Climate Control in Greenhouses. Expert Consultation Workshop on Greenhouses in the Antalya Region 0-22: 13-17.