Co-Authors:
Rigakis, N., University of Thessaly, Dept. of Agriculture Crop Pro-duction and Rural Environment, Fytokou St., Volos, Greece
Katsoulas, N., University of Thessaly, Dept. of Agriculture Crop Pro-duction and Rural Environment, Fytokou St., Volos, Greece, Centre for Research and Technology Hellas, Institute for Research and Technology of Thessaly, Dimitriados 95 and P. Mela, Volos, Greece
Teitel, M., Institute of Agricultural Engineering, Agricultural Research Organization, Volcani Center, PO Box 6, Bet Dagan, Israel
Bartzanas, T., Centre for Research and Technology Hellas, Institute for Research and Technology of Thessaly, Dimitriados 95 and P. Mela, Volos, Greece
Kittas, C., University of Thessaly, Dept. of Agriculture Crop Pro-duction and Rural Environment, Fytokou St., Volos, Greece, Centre for Research and Technology Hellas, Institute for Research and Technology of Thessaly, Dimitriados 95 and P. Mela, Volos, Greece
Abstract:
The objective of this work was to study and model the ventilation rate in screenhouses. Thus, microclimate variables and crop transpiration as well as the air velocity were measured in three screenhouses covered by different screens: (i) a clear insect-proof screen, (ii) a white insect proof screen and (iii) a green shade screen, with values of shading factors to solar radiation measured in the lab of about 13%, 34% and 36%, respectively. The porosity of the screens was found 0.46 for the insect proof and 0.63 for the shading screen. The ventilation rate was estimated using the decay rate 'tracer gas' method, using the water vapour as tracer gas. The results showed that the insect proof screens reduced at the same rate the inside screenhouse air velocity, since they had the same geometrical characteristics. The internal air velocity in the insect proof and the shading screenhouses was about 20% and 44%, respectively, of that measured outside. The ventilation rate data obtained were used to calibrate a model that can be used for the prediction of ventilation rate in screenhouses, taking into account the geometrical characteristics of the screens used and of the screenhouse and the outside wind speed. © 2014 Elsevier B.V.
תפריט נגישות
ניגודיות עדינה
מונוכרום
הדגשת קישורים
חסימת אנימציה
פונט קריא
סגור
איפוס הגדרות נגישות
להורדת מודול נגישות חינם
