Numerical Investigation of Small-Scale Adsorption Cooling System Performance Employing Activated Carbon-Ethanol Pair

Abstract

Adsorber heat exchanger design has great importance in increasing the performance of the adsorption-based cooling system. In this study, a transient two-dimensional axisymmetric Computational Fluid Dynamics (CFD) model has been developed for the performance investigation of finned tube type adsorber using activated carbon and ethanol as the working pair. The operating conditions of the cooling system were 15, 20 and 80 for evaporation, cooling and heating temperatures, respectively. The simulated temperature profiles for different adsorbent thicknesses were validated with those from experimental data measured in our laboratory. Moreover, the error in mass and energy balance were 3% and 7.88%, respectively. Besides, the performance investigation has been performed for cycle time ranging from 600 s to 1400 s. The optimum cycle time was 800 s and the corresponding evaluated specific cooling power (SCP) and coefficient of performance (COP) were found to be 488 W/kg and 0.61, respectively. The developed CFD model will be used for fin height and fin pitch optimization and can be extended to other adsorbent-adsorbate based adsorption cooling system.

Experimental and Simulation Study of a Solar Assisted Two Bed Adsorption Refrigeration System Using Activated Carbon-Methanol

“…A Computational Fluid Dynamics (CFD) model was developed by Khanam et al [29] to assess the performance of a finned tube type adsorber utilising a pair of activated carbon and ethanol. The operating temperatures of the cooling system were 80℃, 20℃ and 15℃ for heating, cooling and evaporation respectively.…”

“…The following section discusses the equations of energy balance for the various components of ARS. The equations are written by taking into account the mechanism of heat transfer occurs inside the components and based on the similar studies made by Pinto et al [14], Khanam et al [29], Baiju et al [32], Gado et al [33], Passos et al [37], Sakoda and Suzuki [38], and so on.…”

Evaluation of the Adsorptive Process on Adsorbent Surfaces as a Function of Pressure in an Isosteric System Compared with Adsorption Isotherm

“…Van der Waals forces and hydrophobic interactions produce the attraction (not covalent bonding) [5]. The state of equilibrium is achieved after a protracted period during which adsorbing molecules settle on the adsorbent surfaces [15]. Working pairs for adsorption are typically chosen depending on the temperature of the available heat source and the cooling load [16].…”

“…All adsorption models are based on the adsorption equilibrium. The implementation of both kinetic and dynamic adsorption models requires knowledge of the adsorption equilibrium [14,15].…”

Comparative Studies on Solar Assisted Silica Gel- Water and Activated Carbon-Methanol Based Adsorption Refrigeration System

“…There are studies on solar based adsorption by Kairul Habib et al [20], Wissam H. Khaleel [21], N. V. Ogueke et al [22], Khattab et al [23], Hassan et al [24], Mohammed Ali Hadj Ammar et al [25], etc. many theoretical studies were found by researchers like V Baiju et al [26], A. Asif Sha et al [27], H. T. Chua et al [28], Sakoda et al [29], Xiaolin Wang et al [30], Yongling Zhao et al [31], Marzia Khanam et al [32] etc. Research on activated Carbon with different adsorbates such as ethanol, methanol, R-134a etc.…”