Influence of Altitude on the Performance of Desiccant-Cooling Systems

The impact of height above sea level (i.e. ambient pressure) on the performance of the ventilation cycle desiccant-cooling system and its components has been studied using computer simulations. The impact of ambient pressure depends on whether the system was designed for fixed-mass flow rate or fixed-volume flow rate operation. As the ambient pressure is decreased from 1.0 to 0.8 atm, the system thermal coefficient of performance increases by 8% for both fixed-mass and fixed-volume flow rate; the cooling capacity of the system is decreased by 14% for the fixed-volume flow rate system and increased by 7% for the fixed-mass flow rate system. The electric power requirements for the system with fixed-volume flow rate did not change; for the fixed-mass flow rate system, it increased by 44%. The overall coefficient of performance increased up to 5% for the fixed-volume flow rate system and decreased up to 4% for the fixed-mass flow rate system.