Compact, efficient carbon-ammonia adsorption heat pump

The modelling, design, construction and experimental testing of a carbon-ammonia adsorption heat pump is presented. The main objective of the research was to design, manufacture and test an adsorption generator with low thermal mass and high power density. The adsorption generator developed was a stainless steel, nickel brazed plate heat exchanger. Computational modelling of the generator with thermal wave and multiplebed cycles revealed that multiple-bed cycles give a superior trade-off between efficiency and power density. Further modelling was carried out to evaluate the performance of the adsorption generator in a four-bed gas-fired domestic heat pump system. The proposed system is air-source and could deliver a nominal heating power of 7 kW and a seasonal heating COP of 1.35, equivalent to a one third reduction in gas consumption in comparison to a condensing boiler. The systems performance was compared to a vapour compression heat pump on running costs and CO2 emissions and was found to be similar or better in all cases. The adsorption generator was tested in a two-bed air-source heat pump system and achieved heating powers from 7 to 11 kW and a heating COP of between 1.4 and 1.6. Specific heating power ranged from 3.9 kW kg-1 to 6.1 kW kg-1, equivalent to specific cooling powers of between 1.1 kW kg-1 and 2 kW kg-1, which is a significant increase in power density compared to the state of the art.EThOS - Electronic Theses Online ServiceGBUnited Kingdo