Experimental Analysis of Mist Injection and Water Shower Indirect Evaporative Cooling in Harsh Climate

Abstract

An experimental investigation of the performance of a direct-indirect evaporative cooling fresh air handling unit with different modes of operation is presented. Linear regression analysis is used to fit the experimental results, and the correlation coefficient is evaluated. It is found that the highest temperature reduction of 18.8℃ is achieved across the heat exchanger for the tested unit when the water shower mode is implemented at an ambient dry-bulb temperature of 44℃ in conditions of relative humidity less than 20%. In the water shower and the combined mist injection and water shower modes of operation, the temperature reduction across the heat exchanger generally reduces, with increasing relative humidity. Furthermore, the results showed that water consumption increased with increasing ambient dry-bulb temperature and decreased with increasing ambient relative humidity. Finally, the lowest energy consumption of 1.64 kWh occurred with the water shower mode operated at peak dry-bulb temperature design condition. The energy consumptions for the mist injection mode of operation were 1.89 kWh and 2.15 kWh for the peak dry-bulb temperature and peak wet-bulb temperature design conditions, respectively. At these design conditions, the energy consumptions of the combined mist injection and water shower mode of operation are 2.7 kWh and 2.83 kWh, respectively.

Embracing the Evaporative System in Air Conditioning Technology for Efficient Cooling Solutions

“…With a 25% reduction in condenser fan speed, the COP values were 4.86 and 4.77 for the top and middle nozzle locations. Additionally, reducing the fan speed further by 50% yielded COPs of 4.78 [15]- [17] and 4.72 for the same 3 upper and middle nozzle configurations. From these experimental results, it can be concluded that supplementing the condenser with 3 evaporative cooling nozzles leads to significant COP improvements, even when the condenser fan speed is reduced by up to 50%.…”

“…Effective design is crucial for the successful implementation of evaporative cooling systems. Factors such as air velocity, wet-bulb temperature, and water distribution play pivotal roles in optimizing system performance [15]. This section outlines the key considerations in designing evaporative cooling systems, including the selection of materials, control mechanisms, and integration with existing HVAC systems.…”