Sensible and Evaporative Cooling of Greenhouse via Wind-tower Integration

Wind tower has been used as traditional Arabic architectural element to create passive ventilation in buildings for human comfort in hot and arid regions. Greenhouse agriculture has been a profitable technology despite the large energy and water need. Integrating these technologies will result in substantial energy and water saving. Sensible cooling is attempted first in the greenhouse. The time evolution of the temperature variation of the flowing air and temperature of conduit walls along the height of the tower and at the greenhouse exit are studied. Parameters like tower height, made-off materials, entry temperature, and wind velocity are considered in the quest to reach to lowest temperature at the greenhouse exit. A high-fidelity model is developed governed by the non-isothermal Navier-Stokes flow in conjugated heat with the conduit material in unsteady and turbulent flow regime. The continuity, momentum, energy, and turbulent scalars are solved simultaneously and results are compared/validated against the first principle of convective-sensible heat for conduit temperature. Results reveal that additional height enable more cooling energy storage, however this cooling energy is non-sustainable and depletes in a relatively short time over several minutes. This suggests utilization of very high specific heat materials or integration of trans-evaporative cooling. The latter is simulated and results are favorable and shows to bring the needed cooling to the greenhouse.