الفهرس 
Chapter 1 IntroductionOnly 14 pages are availabe for public view
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Abstract
Ozone depletion and global warming are the most important environmental issues at the moment especially in energy related sectors. As well as the raising of oil price causes many economical problem and has affected the energy industry worldwide. Cooling and heating systems consume major amount of electrical power which is produced from oil burning in the thermal power stations. Scientists and engineers are working hardly at the moment to find another solution to develop technologies for cooling and heating systems that have less oil dependency. The utilization of solar and waste heat becomes a considerable method to reduce the oil consumption. One of the most promising systems now is the system which depends on sorption technology. Sorption systems can be classified into absorption and adsorption systems. However absorption systems are more efficient than adsorption system, adsorption systems are more favorable since adsorption systems have the ability to operate by very low temperature thermal source (about 60-80oC). So, it is suitable to use solar radiation or low temperature waste gases come from factors, thermal power plant and automobiles engines as a thermal source to operate these cooling and heating systems.
The main difference between the traditional vapor compression cooling/heating systems and the adsorption cooling/heating systems is the way which used to suck the refrigerant vapor from the evaporator and deliver it to the condenser. In traditional vapor compression cooling and heating systems, suction and delivery are performed by mechanical compressor which is always connected to an electrical motor. In adsorption systems, suction from evaporator and delivery to condenser are performed in another way.
In adsorption systems, adsorber/desorber works as a thermal compressor. The adsorber can be described as a heat exchanger used for cooling and heating the adsorbent material. The ability of adsorbent material to suck the refrigerant vapor from the evaporator increases by cooling. Contrarily, adsorbent can deliver its content of refrigerant to the condenser by heating. In recent years, FAM-Z02 zeolite-water pair is extensively used in adsorption systems since FAM-Z02 zeolite has high ability to adsorb water vapor also FAM-Z02 zeolite-water pair has no effect on global warming and it is an environmental friend. In this work, the basic kinetics of adsorption process has been firstly studied using the constructed experimental set-up to investigate the effect of pressure and temperature on the adsorption process. Since refrigerant pressure difference between outside and inside the adsorbent represents the driving force for adsorption process, the experiments performed by two ways to create this pressure difference. The first one is by making the refrigerant vapor pressure outside higher than its pressure inside of adsorbent material. This pressure difference makes the adsorption process continue until reaching equilibrium state. In the second way this pressure difference is achieved by decreasing the pressure of refrigerant vapor inside the adsorbent by means of cooling the adsorbent. Cooling makes the adsorbent able to adsorb the vapor inside bores which results in reduction of the inside pressure and forces the adsorption process to continue until the adsorbent achieves its saturation state according to the lowest temperature achieved within the adsorbent material. A dynamic modeling simulation of experimental set-up proposed and used during this study is performed. The objective of the kinetics modeling is to carry out sensitivity analysis on adsorption process data for FAM-Z02 zeolite-water pair in order to investigate and discover their mass and heat transfer parameters. The rate of vapor adsorption in FAM-Z02 zeolite is mainly controlled by both mass and heat mechanisms. The evaluation of heat and mass transfer rates accompanied with such an adsorption process is, therefore, a very important aspect in designing and optimizing the operation of an adsorption chiller/heat pump.
Moreover, another objective of this study is to investigate the influence of the parameters affecting the performance of adsorption cooling system with FAM-Z02 zeolite-water and Silica gel-water pairs such as cycle time, heating temperature, cooling temperature, evaporator temperature, grains-heat exchanger surface contact heat transfer coefficient, grain size and adsorbing /desorbing bed layer thickness. Moreover, a comparison between the system performance using FAM-Z02 zeolite-water and silica gel-water pair is performed. The performance criterions considered by the comparison are the coefficient of performance (COP) and Specific cooling capacity (SCP). Systems using FAM-Z02 zeolite have been identified by greater SCP and COP than those using silica gel. Results show also that the optimum thickness of adsorbing/desorbing bed layer is about 4mm in case of FAM-Z02 zeolite and about 3mm in case of silica gel as well as the optimum cycle time is 900 sec for both adsorbents.