Slide 1.pngSlide 2.pngSlide 3.pngSlide 4.pngSlide 5.pngSlide 6.png

Pr. Zhong-Xian YUAN

Beijing University of Technology, China


Talk Title
 Experimental optimization of concentrating solarsystem for adsorption cooling in summerand heating in winter

Talk Abstract

Using the solar energy as the driving heat source, a well-designed solar heat pump system can not only supply the cold demand to the air conditioning system in the summer, but it is also possible to provide the heat supply in the winter. Towards such a goal we set up an experimental system of solar adsorption refrigeration system in the campus of Beijing University of Technology, China, and completed a series of test in recent years. The experimental system consisted mainly of a small parabolic trough solar collector with an automatic solar-tracking system, adsorption bed of vacuum tube, evaporator/condenser, and a data acquisition system. For the refrigeration cycle in summer, the cold and desorbed adsorbent material was able to adsorb the refrigerant vapor strongly, and then caused a cold effect in the surrounding. The adsorbed material must be heated up to desorb the water vapor so that the process of adsorption refrigeration could be repeated. The collected solar energy was responsible to heat the bed up.

Two working pairs of SAPO-34/water and ZSM-5/water were tested in the experiment. SAPO-34 and ZSM-5 represents two types of molecular sieve zeolite that features with a good adsorption ability to water vapor. The experimental results revealed that the heat transfer of the ZSM-5 zeolite was better than that of the SAPO-34 zeolite, while the mass transfer of SAPO-34 zeolite was superior to the other one. In general, the SAPO-34 zeolite showed a better result and was more suitable to use in a solar adsorption refrigeration system. It was also found that there existed a maximum value of the COP and the SCP of the system with the change of the adsorption time, but the optimal adsorption time to the COP and the SCPwere not the same. In order to improve the poor heat transfer of the adsorption bed, the bed was further modified with built-in fins and tested with the SAPO-34/water working pair. With the fin number changing in between 2 to 8, the COP was improved from the original 0.127 to 0.160, and the cycle time decreased from 120 minutes to 59 minutes as compared to the case without a fin.

The same experimental rig was also experimented for the performance as used to the heating purpose in winter to a makeshift house of 10.64 m2 area. The experimental results suggested that the thermal efficiency of the system had reached 70% in average. As it was evaluated at the criterion that the air inlet temperature into the room was over 30oC, the heat-supply time of the solar system was about 5 to 7 hours in a sunny day. Correspondingly, the room temperature was 10 oC~15oC higher than the outside ambient temperature. The results of the current study may provide some helpful information for those who are interesting in the thermal application of the solar energy and the engineers majoring in the cleaner heat supply. 

Short Biography

Ph.D,Professor, College of Environmental and Energy Engineering, Beijing University of Technology, China

He received his PhD degree in Xi'an Jiao Tong University of China in 1997. From 2001 January to 2002 July he affiliated in Southern Illinois University Edwardsville, US as a visiting professor. From 2009 February he conducted a two year’s mission as the Chinese director of Confucius Institute Opole, Poland. His research interests include the numerical heat transfer and CFD, management of thermal system, and solar energy. So far he has published over 70 technical papers in Int. J. Numerical Methods in Fluids, Int. J. Numerical Methods for Heat and Fluid Flow, Int. J. Heat and Mass Transfer, Int. Comm. Heat and Mass Transfer, Comm. Nonlinear Science and Numerical Simulation, Heat Transfer Engineering, Solar Energy, Energy Conversion and Management, Experimental Thermal and Fluid Science, Int. J. Thermal Sciences, and some Chinese academic journals. Professor Yuan is a reviewer for the international journals such as J. Enhanced Heat Transfer, Int. J. Numerical Methods for Heat and Fluid Flow, Experimental Thermal and Fluid Science, and Solar Energy, etc.. He has mainly devoted to the study on the solar adsorption cooling technique and the solar thermal engines in the past decade.

Talk Keywords
Solar energy, adsorption refrigeration, solar heating in winter, heat and mass transfer.
Target Audience
Ggraduate and reseach students, Professors and working professionals
Speaker-intro video

The International Conference on Innovative Applied Energy (IAPE’18)