INVESTIGATE STEADY-STATE HEAT AND MASS BALANCE FOR GREENHOUSES PAD-FAN COOLING SYSTEM

Hatem, M. H.; Abdelbary, K. M.; Morsy, K.M.

doi:10.21608/mjae.2008.190276

INVESTIGATE STEADY-STATE HEAT AND MASS BALANCE FOR GREENHOUSES PAD-FAN COOLING SYSTEM

Document Type : Original Article

Authors

¹ Prof. Agric. Eng. Dept., Fac. of Agric., Cairo Unvi., Egypt.

² Assist. Prof. Agric. Eng. Dept., Fac. of Agric., Cairo Unvi., Egypt.

³ Agric. Engineer, Economic Affairs Sector, Ministry of Agriculture., Egypt.

10.21608/mjae.2008.190276

Abstract

This research work aims to investigate the steady-state heat and mass balance for greenhouses that use pad-fan cooling system. It also studies the evaporative cooling system efficiency in fiberglass modified Quonset greenhouse. Dry-bulb and wet-bulb temperature were measured, relative humidity and cooling efficiency were calculated and predicted dry-bulb temperature and relative humidity inside the greenhouse throughout the proposed simple model was performed. Dry–bulb temperature and relative humidity were homogeneous altitude along the fiberglass greenhouse under investigation (16 m long, average of fan air velocity was 5.23 m/s and pad-face air velocity was 1.2 m/s). The obtained results showed that, the predicted data of dry-bulb temperature inside the greenhouse were validated well with that measured.

Main Subjects

Biosystems Engineering

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