Dynamic Modeling of Greenhouse Micro-Climate Conditions

Öz

Determination of micro-climatic conditions in the greenhouse in our country where greenhouse is becoming more important day by day is important for the effectiveness of air-conditioning systems used to improve plant quality. By setting a dynamic mathematical model using hourly meteorology data, micro-climatic parameters (greenhouse dry-bulb temperature and relative humidity ratio, ground surface temperature) were determined by the presence and absence of heating load on the coldest days of winter, 15-18 January, in a greenhouse in the Silifke district of Mersin province. On January 15, the average temperature of the outdoor environment was 10.8ºC and the heating load of 0.796 kWh/m2day was needed to increase the temperature inside the greenhouse to 15ºC. On 18 January, the average outdoor temperature was 5.3 ºC and the heating load of 1.67 kWh/m2day was needed. Compared to ideal microclimate conditions, the time periods for heating, ventilation and humidification of the greenhouse were determined. The effect of soil surface temperature on the inside temperature has been demonstrated. Plant transpiration has been found to be very effective in the change of greenhouse humidity. 

Anahtar Kelimeler

• Greenhouse,Heat and mass balance equations,Ground temperature,Plant transpiration

Sera Mikro-İklim Şartlarının Dinamik Modellenmesi

Öz

Seracılığın her gün daha çok önem kazandığı ülkemizde sera içi mikro-iklim koşullarının tespit edilmesi ürün kalitesini artırmak amacıyla kurulan iklimlendirme sistemlerinin etkinliği açısından önemlidir. Saatlik meteoroloji verilerinin kullanıldığı dinamik bir matematik model oluşturularak Mersin ili Silifke ilçesinde yer alan bir seranın kışın en soğuk günleri olan 15-18 Ocak tarihlerinde mikro-iklim değerleri (iç ortam sıcaklık ve bağıl nem, toprak sıcaklığı) ısıtma olması ve olmaması durumuna göre tespit edilmiştir. 15 Ocak günü dış ortam ortalama sıcaklığı 10,8 ºC iken sera içini 15 ºC sıcaklığa çıkarmak için 0,796 kWh/m2gün ısıtma yüküne ihtiyaç duyulmuştur. 18 Ocak günü ise dış ortam ortalama sıcaklığı 5,3 ºC iken 1,67 kWh/m2gün ısıtma yüküne ihtiyaç duyulmuştur. İdeal mikro iklim şartları ile kıyaslandığında ısıtma, havalandırma ve nemlendirme yapılması gereken zaman dilimleri ortaya konmuştur. Toprak yüzey sıcaklığının iç ortam sıcaklığına etkisinin yansıra bitki transpirasyonunun sera içi nem oranı değişiminde çok etkili olduğu tespit edilmiştir. 

Anahtar Kelimeler

• Sera,Isı ve kütle denklikleri,Toprak sıcaklığı,Bitki transpirasyonu

Kaynakça

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