Design and experimental testing of an adsorbent bed for a thermal wave adsorption cooling cycle

Çağlar, Ahmet
Poor heat and mass transfer inside the adsorbent bed of thermal wave adsorption cooling cycles cause low system performance and is an important problem in the adsorbent bed design. In this thesis, a new adsorbent bed is designed, constructed and tested to increase the heat and mass transfer in the adsorbent bed. The adsorbent bed is constructed from a finned tube in order to enhance the heat transfer. Additionally, the finned bed geometry is theoretically modeled and the model is solved time dependently by using Comsol Multiphysics software program. The distributions of dependent variables, i.e. temperature, pressure and amount adsorbed, are simulated and plotted in Comsol Multiphysics. In the model, the dependent variables are computed by solving the energy, mass and momentum transfer equations in a coupled way and their variations are investigated two-dimensionally. The results are presented with multicolored plots in a 2-D domain. Furthermore, a parametric study is carried out for determining factors that enhance the heat and mass transfer inside the adsorbent bed. In this parametric study, the effects of several design and operational parameters on the dependent variables are investigated. In the experimental study, the finned tube is tested using natural zeolite-water and silica gel-water working pairs. Temperature, pressure and amount adsorbed variations inside the adsorbent bed at various operating conditions are investigated. After that, a second adsorbent bed with a larger size is constructed and tested. The effect of the particle diameter of the adsorbent is also investigated. The experimental and theoretical results are compared.


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Citation Formats
A. Çağlar, “Design and experimental testing of an adsorbent bed for a thermal wave adsorption cooling cycle,” Ph.D. - Doctoral Program, Middle East Technical University, 2012.