| Adsorption refrigeration is a kind of environmentally friendly refrigeration technologybeing able to use low grade thermal energy and refrigerants used are natural medium. It hasbeen regarded as one of the primary technologies for alternation to CFCs conventionalcompression refrigeration systems in the21st century.Now that adsorption working pair is the heart of adsorption refrigeration and directlydetermines system performance, so it is crucial to explore new adsorption working pairs. Inthis thesis, different adsorption performance testing methods are compared and liquid levelmethod is chosen, based on which an adsorption test rig is designed and built. The sealing ofthe system is the toughest problem encountered due to the low pressure. A lot of methods aretried to solve the leakage problem. However, since the sealing of the ball valve is notguaranteed in high vacuum environment, a new scheme of the test rig is proposed and built.Water adsorption performance of composite adsorbents with5%and7.5%carbonnanotube is tested in the new test rig. Experimental results show that the equilibriumadsorption quantity of composite adsorbent with5%carbon nanotube is0.20126g/g whenadsorption temperature and evaporation temperature are50℃and20℃respectively.When the adsorption temperature is80℃, the equilibrium adsorption capacity of compositeadsorbent with7.5%carbon nanotube is0.16486g/g, which is44.6%higher than that ofcomposite adsorbent with5%carbon nanotube. While when the adsorption temperature is70℃, the equilibrium adsorption quantity of composite adsorbent with7.5%carbonnanotube is0.18914g/g, which is36.5%higher than that of composite adsorbent with5%carbon nanotube. The residual vapor is also considered and the conclusion is that it will notinfluence the final adsorption quantity and its influence decreases with time and temperature.So carbon nanotubes can improve the adsorption quantity and have potential application insolar adsorption refrigeration. |
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