الفهرس 
Physical AdsorptionOnly 14 pages are availabe for public view
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Abstract
With the concern over the ozone layer depletion due to CFCs, global warming due to HFCs as well as CO2 emissions and the continuous increase in primary energy costs, the interest in more efficient energy conversion systems has gradually increased. The state of the art in gas-fired heating appliances is the condensing boilers connected to floor heating systems. In order to realize more effective gas-fired heating systems and, consequently, more reduction in CO2 emissions, gas-fired adsorption heat pumps seem to be a promising solution. In cold regions of the world, ambient temperatures in the range of –5 °C or lower are quite common. Accordingly, the concept of common condenser and common evaporator with a throttling valve in-between can’t be applied with water as a refrigerant. This is to avoid freezing and blocking the connecting tube between the two components. Alternatively, using two vacuum sealed modules, each of them contains an adsorber/desorber and an evaporator/condenser heat exchangers, becomes the remaining choice. As zeolite requires desorbing temperatures above 150 °C, the concept of heat recovery between the two adsorbent heat exchangers is excluded. Because the costs of the circulation pumps is high due to the required high temperature resistance. Accordingly, the thermal wave concept has been proposed between the two adsorbent heat exchangers for the heat recovery. In this study, a two modular zeolite-water adsorption heat pump based on the thermal wave concept has been investigated. A first and second law analysis has been carried out to identify and evaluate the influencing parameters on the coefficient of performance (COP) of the adsorption heat pumps. The analysis results in a novel equation for the reversible COP of such heat pumps. A two modular adsorption heat pump has been designed and fabricated. Each module is composed of two heat exchangers contained in a hermetic stainless steel vessel. The first heat exchanger is the adsorber/desorber located at the top of the vessel, while the second is the evaporator/condenser heat exchanger.