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Current work emphasises the counter flow liquid desiccant dehumidification system (LDDS) that uses a novel fabricated packing frame filled with biomass-based wood shaving material which used Calcium chloride as liquid desiccant. Experiments are carried out by varying mass flow rate, temperature, and concentration. Various dehumidification performance parameters such as moisture removal rate (MRR), Coefficient of performance, Dehumidification efficiency, mass transfer coefficient, change in humidity, and air temperature are studied. System gave an increased dehumidification performance at high concentration and low inlet temperature of the desiccant. Results revealed that when the flow rate is maintained between 0.5 and 0.55 Litres per minute, optimised performance parameters like energy consumption, MRR, COP, dehumidification efficiency are 662 Watts, 0.57 g/s, 2.7, 54% correspondingly. [ABSTRACT FROM AUTHOR]

Recent technological advancements in the HVAC industry enable optimized occupant thermal satisfaction and system efficiency, thanks to better control of the comfort parameter. Current work aims to automatically control the thermal comfort parameters: dry bulb temperature, air-velocity, and relative humidity. This is achieved using an air handling unit (AHU) equipped with a fresh air control for air quality control, a chiller unit that runs on a VCR cycle for cooling and dehumidification, an ultrasonic mist humidification system, and an air volume control system installed in the ductwork for temperature control. These systems are automatically controlled based on the feedback from various sensors installed in the target space to fit to the ASHRAE Standard 55. Experiments are conducted for varying air velocity at different daytime periods in Dubai. Air temperature and humidity are measured at each stage of the AHU. Total time for achieving thermal comfort is recorded. Results indicated that maximum coefficient of performance (COP), dehumidification effectiveness (DE), humidification effectiveness (HE), predicted mean vote (PMV) and bypass factor were 8.60, 0.96, 36%, −0.62 and 0.48 respectively when outdoor conditions reached 42 °C and 50% RH. The operational efficiency of the current adaptive-controlled system is found to be 21.50% more efficient than a conventional system. • Integration of AHU with an adaptive control unit. • A transient analysis to achieve thermal comfort conditions was tested. • Maximum saving of 21% of power for a heat load of 200 Watts. • Operation cost is reduced by 26% compared to a conventional AC unit. [ABSTRACT FROM AUTHOR]