Magnetic Field Enhancement in Ammonia-Water Absorption Refrigeration Systems

Moradeyo K. Odunfa, Richard O. Fagbenle, Olanrewaju M. Oyewola, Olayinka S. Ohunakin

Mechanical Engineering Department, Covenant University, Ota, Nigeria.
Mechanical Engineering Department, Obafemi Awolowo University, Ile-Ife, Nigeria.
Mechanical Engineering Department, University of Ibadan, Ibadan, Nigeria.

DOI: 10.4236/epe.2014.64007                

Abstract

Absorption enhancement has been considered as an effective way of improving coefficient of performance (COP) of refrigeration systems and magnetic enhancement is one of these methods. A model of magnetic field enhancement in ammonia-water absorption systems is presented in this paper. A numerical model using finite difference scheme was developed based on the conservation equations and mass transport relationship. Macroscopic magnetic field force was introduced in the momentum equation. The model was validated using data obtained from the literature. Changes in the physical properties of ammonia solution while absorbing both in the direction of falling film and across its thickness were investigated. The magnetic field was found to have some positive effect on the ammonia-water falling film absorption. The results indicate that absorption performance enhancement increased with magnetic intensity. The COP of simple ammonia solution absorption refrigeration system increased by 1.9% and 3.6% for magnetic induction of 1.4 and 3.0 Tesla respectively.

Keywords

Ammonia-Water Absorption Refrigeration, Magnetic Field Force, Ammonia Solution Concentration, Coefficient of Performance, Finite Difference Scheme, Numerical Solution

Conflicts of Interest

The authors declare no conflicts of interest.

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