Numerical investigations of solar-assisted hybrid desiccant evaporative cooling system for hot and humid climate

Abstract

This article presents numerical investigations of the solar-assisted hybrid desiccant evaporative cooling system integrated with standard air collectors for applications under the hot and humid climatic conditions of Kuwait city. The objective is to introduce the energy-efficient and carbon-free solar-assisted hybrid desiccant evaporative cooling system to alleviate the principal problems of electricity consumption and carbon emissions resulting from the use of the conventional vapor-compression cooling systems. In the normal building, during cooling load operation, the solar-assisted hybrid desiccant evaporative cooling system can cope with the cooling load particularly sensible by evaporative cooling and latent through desiccant dehumidification. The outcomes of this work indicate that solar-assisted hybrid desiccant evaporative cooling device integrated with air collectors is capable of providing average coefficient of performance of 0.85 and has the potential to provide cooling with energy saving when compared with conventional vapor-compression refrigeration systems. It was concluded that under the intense outdoor environmental conditions (ambient air at greater than 45°C and 60% relative humidity), the delivered supply air from the evaporative cooling was nearly at 27°C and 65% relative humidity. To solve this problem, the system was assisted with conventional cooling coil (evaporator of heat pump) to supply air at comfortable conditions in the conditioned space.

Applicability of Direct Evaporative Cooling for Low-Rise Residential Building in Surabaya

“…This recommendation can improve comfort and is relatively affordable. Other proposals are a desiccant-dehumidifier (Mujahid Rafique et al, 2015;Suwannapruk et al, 2020) and solar assisted dryer (Abaranji et al, 2020;Hussain et al, 2020). A combination of direct and indirect evaporative cooling was also put forward to tackle the humidity problem (Darmawan et al, 2021).…”

Investigation of a Storage Type Solar-Driven Solid Desiccant Cooling System

“…The sorption heat generated during this process is eliminated by using a heat exchanger at the exit of the desiccant chamber (10). With the heat exchanger, the sorption heat of the air is transferred to a water tank with the water circulation (11)(12)(13) and the air temperature is reduced back to nearly ambient temperature. Finally dry air enters the evaporative cooling chamber and its temperature is reduced to the desired level.…”

“…During the charging process the Eppley Precision Spectral Pyranometer (PSP) was used for measuring the solar intensity on the solar collector. On the other hand, in discharging process temperature and humidity of ambient air (6), inlet-outlet of desiccant unit (8-9) also outlet of heat exchanger and evaporation chamber (10)(11)(12)(13)(14) were measured with the installed SHTC3 Sensiron type sensors. A PASCO-GLX airflow meter was used to measure the airflow speed at the outlet of the system (14).…”

“…A PASCO-GLX airflow meter was used to measure the airflow speed at the outlet of the system (14). Also a thermometer has been used to measure the circulation water temperature (11)(12)(13) inside the water tank. The measurement ranges of utilized sensors and their accuracies were listed in Table 1.…”

“…75% of the energy consumed by this air handling system comes from renewable sources. Hussain et al [11] presented numerical investigations on a solarassisted hybrid DAEC system integrated with solar air collectors for hot and humid climatic conditions of Kuwait. The outcomes of this work indicated that the proposed system is capable of providing average coefficient of performance of 0.85.…”