A Mathematical Model of an Evaporative Cooling Pad Using Sintered Nigerian Clay

Chukwuneke Jeremiah Lekwuwa, Ajike Chinagorom Ogbu, Achebe Chinonso Hubert, Okolie Paul Chukwulozie

Department of Mechanical Engineering, Nnamdi Azikiwe University, PMB 5025, Awka, Nigeria.

DOI: 10.4236/jmmce.2012.1111119                

Abstract

Overtime, reduction in the amount of heat generated in engineering systems in operations have been of great concern and have continuously been under study. It is in line with the above that this research work developed a mathematical model of an evaporative cooling pad using sintered Nigerian clay. A physical model of the evaporative cooling phenomenon was developed followed by the derivation of the governing equations describing the energy and mass transfer for the clay model from the laws of conservation of continuum mechanics. A set of reasonable and appropriate as-sumptions were imposed upon the physical model. Constitutive relationships were also developed for further analysis of the developed equations. The finite element model of numerical methods was used to analyse the energy transfer governing equations which resulted in the determination of the temperature of the exposed boundary surface at any given time, t2 after the commencement of the evaporative cooling processes. In this paper, it was found out that surface temperature differences could be as much as 6?C in the first cycle of evaporative cooling with the potential of further reduction. Further, an equation for the prediction of the effectiveness of an evaporative cooling system using clay modeled cooling pads was developed. The findings in this research work can be applied in the design, construction and maintenance of evaporative coolers used to dissipate waste heat when a large amount of natural water is not readily available or if for environmental and safety reasons the large water body can no longer absorb waste heat.

Keywords

Evaporative Cooling; Nigerian Clay; Finite Difference Model; Energy Transfer; Cooling Pad; Moulded Clay Material; Heat Transfer; Refrigeration; Temperature

Conflicts of Interest

The authors declare no conflicts of interest.

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