A transient performance evaluation of a porous evaporative cooler for preservation of fruits and vegetables

A transient performance of a porous evaporative cooling system was carried out using mathematical models developed from the first principles. The models are based on energy and mass balance analysis on different sections of the evaporative cooler. The developed models were solved using a FlexPDE computational fluid dynamics analyzer, based on the finite element, to generate numerical solutions. The models developed were validated using experimental data from a properly designed, constructed, and tested an evaporative cooler and subsequently used to determine the evaporative cooler performance during four different periods of the year covering the two major climatic seasons experienced in Nigeria. Results obtained showed a reduction in the storage chamber temperature by up to 9 °C from the ambient air condition which was within the range of 22–33 °C. Furthermore, it was observed that it performs best during the dry seasons as compared to the wet season. However, during both seasons, the cooling chamber temperature significantly remained below the ambient value. Thus, the evaporative cooler can serve as an effective means of reducing heat-induced post-harvest losses incurred by farmers while also helping in combating climate change since it uses only water and does not require any external energy input.