Adsorption Cooling Performance Simulation of Silica Gel-Water Pair

Alzam Altof Ayob; Fauziah Jerai

Alzam Altof Ayob
Fauziah Jerai

Abstract

Global warming is the current issue that we have right now which is caused by the greenhouse gases. Refrigeration technology such as the adsorption cooling system does not release greenhouse gases in the air. This is due to the fact that the system only uses water as its working fluid. In this project, the silica gel-water is used as a working pair for the adsorption cooling system. The water is the adsorbate, while the silica gel is the adsorbent. The first objective of this study is to compare the simulation result from MATLAB software and the experimental result based on the previous research. The second and third objective are to determine the optimum adsorption/desorption time as well as precooling/preheating time based on the MATLAB simulation. Several mathematical equations are needed in order to develop one stage with two beds adsorption cooling system in MATLAB. The required equations are the adsorption kinetics, adsorption isotherms, COP (Coefficient of Performance), mass balance, heat and energy balance for system beds, condenser as well as evaporator. Adsorption, desorption, preheating and precooling are the processes in this system. By using these processes, four distinct modes are generated and named as Mode A, B, C and D. In this study, there are 3 conditions for the inlet temperature of chilled water, hot water and cooling water. The comparison between the simulation result and experimental result will be made in terms of the COP and the temperature profile of adsorber as well as evaporator.

References

Allouhi, A., Kousksou, T., Jamil, A., and Zeraouli, Y., (2014). Modeling of a thermal adsorber powered by solar energy for refrigeration applications. Energy,75,589-596.
Al Mubarak, A., Zaim, M., & Jerai, F. (2020). Investigation of Cycle Time for Adsorption Cooling System. International Journal of Advanced Research in Engineering Innovation, 2(3), 22-31
Fernandes, M. S., Brites, G. J. V. N., Costa, J. J., Gaspar, A. R., and Costa., V. A. F., (2016). Modeling and parametric analysis of an adsorber unit for thermal energy storage. Energy, 102, 83-94.
Ghilen, N., Messai, S., Gabsi, S., Ganaoui, M. E., and Benelmir. R., (2017). Performance Simulation of Two-Bed Silica Gel Water Adsorption Chillers. Global Journal of Researches in Engineering: 1 General Engineering, 17 (3), 41-49.
Hassan, H. Z., (2014). Performance Evaluation of a Continuous Operation Adsorption Chiller Powered by Solar Energy Using Silica Gel and Water as the Working Pair. Energies, 7, 6382-6400.
Mebarki, B., Solmuş, I., Gomri, R., (2016). The Performance Analysis of A Silica Gel/Water Adsorption Chiller and Dynamic Heat and Mass Transfer Characteristics of Its Adsorbent Bed: A Parametric Study. Journal of Thermal Science and Technology, 36 (1), 107-118.
Rahman, A. F. M. M., Ueda, Y., Akisawa, A., Miyazaki, T., and Saha, B. B., (2015). Study of A Silica Gel–Water-Based Three-Bed Dual-Mode Adsorption Cooling Cycle, Heat Transfer Research. 46 (3), 213-232.
Sharafian, A., & Bahrami, M. (2013). Adsorbate uptake and mass diffusivity of working pairs in adsorption cooling system. Int. Journal of Heat and Mass Transfer, 59(2013), 262-271.
Tangkengsirin, V., Kanzawa, A., & Watanabe, T. (1998). A solar-powered adsorption cooling system using a silica gel-water mixture. Energy, 23(5), 347-353.