الفهرس 
CHAPTER ONE INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Problems of energy and drinking water shortage become the biggest challenges facing survival of human beings in some places. It has been considered mandatory employing renewable energy in cooling and desalinating water especially in rural areas where no electricity available. The present thesis introduces an experimental and theoretical study for a hybrid adsorption cooling-desalination system powered by solar energy below 100°C. This system can be powered by low grade heat source as solar energy, which can be operated efficiently at Egyptian weather. A working pair of silica gel-water is used in the present thesis to investigate the performance of a hybrid adsorption cooling-desalination system at different operating conditions. The adsorption characteristics (adsorption isotherms and kinetics) of silica gel-water pair have been investigated at different temperatures from 25 to 55oC. It is found that maximum adsorption capacity is about 0.36 kg/kg of silica gel. Experimental data of the adsorption isotherms are fitted with Dubinin-Astakhov and Freundlich equations. It is found that the Dubinin-Astakhov equation presents a better correlation with the data of experimental work for silica gel-water pair. Linear driving force (LDF) and Fickian diffusion (FD) models have been used to fit the experimental data of the adsorption pair. This fitting has been conducted to determine the numerical values of the theoretical models for further adsorption kinetics simulations. Numerical values of pre-exponential coefficient (Dso) and activation energy (Ea) have been determined as 2.25×10-10 m2/s and 28.665×103 J/kg respectively.
III
A simulation model has been performed to simulate adsorption cooling-desalination system. Based on a lumped-parameter approach, the model is solved using the MATLAB software. The effect of designing and operating parameter on the performance of the adsorption cooling-desalination system has been investigated. The performance results of the adsorption cooling-desalination system are presented in terms of key parameters such as (i) the specific daily water production (SDWP), (ii) the specific cooling power (SCP), (iii) the Coefficient of performance (COP).A test rig has been designed and constructed to validate the theoretical model. The experimental results indicate that there is a good agreement, more than 94% with the theoretical results. Experimentally SCP is measured to be about 112 W/kg of silica gel while producing SDWP of 4 m3 per ton of silica gel and COP 0.45. The two useful effects are obtained from single heat input.