Experimental performance study of a proposed desiccant based air conditioning system

Abstract

An experimental investigation on the performance of a proposed hybrid desiccant based air conditioning system referred as HDBAC is introduced in this paper. HDBAC is mainly consisted of a liquid desiccant dehumidification unit integrated with a vapor compression system (VCS). The VCS unit has a cooling capacity of 5.27 kW and uses 134a as refrigerant. Calcium chloride (CaCl2) solution is used as the working desiccant material. HDBAC system is used to serve low sensible heat factor applications. The effect of different parameters such as, process air flow rate, desiccant solution flow rate, evaporator box and condenser box solution temperatures, strong solution concentration and regeneration temperature on the performance of the system is studied. The performance of the system is evaluated using some parameters such as: the coefficient of performance (COPa), specific moisture removal and energy saving percentage. A remarkable increase of about 54% in the coefficient of performance of the proposed system over VCS with reheat is achieved. A maximum overall energy saving of about 46% is observed which emphasizes the use of the proposed system as an energy efficient air conditioning system.

Renewable Energy Application for Solar Air Conditioning

“…An experimental study show that average primary energy ratio was 1.6 and 30% of energy saving was achieved by liquid solar desiccant cooling system [24]. In another similar experimental study, results show that COP of the desiccant system increased about 54% over vapor compression system with reheat and achieved 33-60% energy savings [25]. In an economic comparison of proposed and conventional liquid desiccant system, results show that payback period of proposed system to return initial cost was 7 years and 8 months [26].…”

Performance of Desiccant-Based Cooling Systems in Hot-Humid Climates: A Review

“…The performance of the DW depends on several parameters which include inlet and outlet process air temperature and humidity, inlet reactivating air temperature and humidity, face velocity of the two air streams, and size of the regeneration segment [57]. Cooling unit: which could be an evaporative cooler or a cold coil with capability to remove the sensible heat while the desiccant handle the latent load [58]. Regeneration heat source: a variety of energy sources can be utilized for this purpose such as solar energy, waste heat, and natural gas heating [59].…”

Dehumidification performance improvement by using liquid desiccant blends – An experimental study

“…A comparative study on the performance of a counter-flow and cross-flow dehumidifier was conducted by Cho et al 16 and they concluded that the counter-flow dehumidifier showed better performance, the cross-flow dehumidifier was more stable, and eliminated the liquid carry-over issue. An experimental investigation of desiccant-based hybrid air conditioning system, using CaCl 2 as a desiccant was performed by Bassuoni et al 17 The proposed system showed 54% greater coefficient of performance (COP) compared to VCR. To improve the performance of CaCl 2 , a cooling medium within the structured packing was provided and it was observed that its dehumidification effectiveness was improved from 0.55 to 0.706, and its moisture removal rate was improved from 0.0034 kg/kg of dry air to 0.005 kg/kg of dry air.…”