Thermal performance assessment of a novel liquid desiccant-based evaporative cooling system: An experimental investigation

This paper presents preliminary findings of the energy analysis of a cooling system with multistage evaporative coolers using liquid desiccant dehumidifier between the stages. The proposed evaporative cooling system utilizes the air humidity for cooling in humid areas and requires no additional water supply. The major energy requirement associated with this cooling system is the energy for regenerating the weak liquid desiccant. In this paper two types of energy namely thermal energy as well as mechanical energy are considered for regeneration. For thermal energy, the heat input for regeneration is supplied from the conventional energy sources such as a simple line heater. Reverse osmosis (RO) process is considered for regeneration by mechanical energy and MFI zeolite membrane is proposed for separation of water from the weak desiccant solution. Energy analysis has been carried out for both methods of regeneration. The results show that the energy consumption is about 25% less for the mechanical regeneration system with 3 % recovery than the thermal energy regeneration system to increase the desiccant solution temperature of 22°C. The COP of the proposed cooling system is defined as the cooling effect by the mass rate of water evaporated in the system divided by the amount of energy supplied to the system, that is, the COP is independent of the energy source.

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Impact of PV/T system on energy savings and CO2 emissions reduction in a liquid desiccant-assisted evaporative cooling system

Advanced Engineering and Technology ◽

10.1201/b16699-8 ◽

2014 ◽

pp. 45-50

Keyword(s):

Co2 Emissions ◽

Energy Savings ◽

Cooling System ◽

Evaporative Cooling ◽

Emissions Reduction ◽

Liquid Desiccant ◽

Evaporative Cooling System ◽

T System

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Experimental Investigation of Thermal Performance of Aluminum Foil Coated with Polyester in a Direct Evaporative Cooling System

Journal of Engineering ◽

10.31026/j.eng.2021.04.01 ◽

2021 ◽

Vol 27 (4) ◽

pp. 1-15

Author(s):

Abbas Magid Taleb ◽

Mohammed Abdulraouf Nima

Keyword(s):

Experimental Study ◽

Experimental Investigation ◽

Relative Humidity ◽

Cooling System ◽

Evaporative Cooling ◽

Aluminum Foil ◽

Adiabatic Process ◽

Direct Evaporative Cooling ◽

Evaporative Cooling System ◽

Positive Impression

An experimental study was carried out for an evaporative cooling system in order to investigate the effect of using an aluminum pad coated with fabric polyester. In the present work, it was considered to use a new different type of cooling medium and test its performance during the change in the wet-bulb temperature and dry-bulb temperature of the supply air outside of the pad, the relative humidity of the supply air, the amount of air supplied (300-600) CFM and also the change of the amount of circulated water (1.75, 2.5, 4.5) liter per minute. A decrease in the WBT of the air was obtained, whereas the WBT of the air entering the pad was 26.5 . In contrast, the WBT of the outside air had reached 23 even though evaporative cooling is an adiabatic process which makes the WBT of the air that comes out of the pad is equal to the entering air WBT. The decrease in DBT is by changing the amount of air and water passing through the aluminum pad, whereas the DBT of the air entering the pad was 45 , while the DBT of the outside air had reached 29 . Also, an essential thing was obtained as this rise in the relative humidity of the air is very small 57%RH compared to the conventional pads, and this gives a positive impression as the air supplied from this pad has less moisture and its ability to carry moisture is much higher than that of air supplied from other pads. This gives a positive impression because the air supplied from this pad has lower humidity and its ability to hold moisture much higher than the air supplied from other traditional pads.

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Annual thermal performance assessment of a regenerative evaporative cooling system under different climate conditions in Mexico

Indoor and Built Environment ◽

10.1177/1420326x211045732 ◽

2021 ◽

pp. 1420326X2110457

Author(s):

Enrique Mitz-Hernandez ◽

Miguel Gijón-Rivera ◽

Carlos I. Rivera-Solorio

Keyword(s):

Thermal Performance ◽

Atmospheric Pressure ◽

Cooling System ◽

Evaporative Cooling ◽

Channel Length ◽

Dew Point ◽

Transfer Model ◽

Climate Conditions ◽

Wide Range ◽

Evaporative Cooling System

A numerical heat and mass transfer model with thermophysical properties dependent on the temperature, humidity ratio and atmospheric pressure was developed. The numerical model was verified and validated against literature, and it showed good agreements. The pseudo-transient model provides a low-cost computational tool to evaluate the potential and performance of a dew point evaporative cooling system for a wide range of extreme climate conditions (BWh, BSh, Cw and Aw from Köppen classification). A parametric analysis of different operational and design conditions in the evaporative cooler was conducted. Results show that there is an optimal channel length for given climatic conditions. The Dew-point evaporative cooling (DPEC) system showed that the best thermal performance corresponds to the climate very arid (Hermosillo – BWh) with 4018 comfort hours (83.1%) followed by the climate arid (Monterrey – BSh) with 3470 comfort hours (90.9%), the mild climate (Puebla – Cw) with 295 comfort hours (100%) and the warm climate (Cancun – Aw) with 3452 comfort hours (62.3%). Finally, an engineering correlation for constant atmospheric pressure and channel length was obtained ([Formula: see text] of 93%).

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