SPATIOTEMPORAL INVESTIGATION OF EVAPORATIVE COOLING OPTIONS FOR GREENHOUSE AIR-CONDITIONING APPLICATION IN PAKISTAN.

This study explores evaporative cooling options for greenhouse air-conditioning for the climatic conditions of Multan (Pakistan). Greenhouse requires temperature and humidity control unit to optimize the environment inside the greenhouse for plants. In this regard, three low-cost lab-scale experimental evaporative cooling (EC) systems (i.e. direct EC (DEC), indirect EC (IEC), and Maisotsenko cycle EC (MEC)) were developed. The thermodynamic performance of the developed systems was analyzed from the viewpoints of the temperature gradient, relative humidity, vapor pressure deficit, and wet bulb, and dew point effectiveness. The MEC, DEC, and IEC systems created a temperature gradient of 18- 21°C, 20-28°C, 27-31°C at ambient temperature 28- 400C for 15th May for the climatic conditions of Multan. The spatiotemporal evaluation of temperature, relative humidity, and vapor pressure deficit (VPD) revealed that plain areas of Pakistan including Punjab province received severe temperature peaks. Whereas relative humidity peaked in monsoon season across the plain areas. Whereas for VPD, plain areas of Pakistan faced severe peaks in the summer months which can be optimized using the MEC system for greenhouse air-conditioning. Thus, the results conclude the MEC system as an optimum air-conditioning option for greenhouse air-conditioning. [ABSTRACT FROM AUTHOR]