Numerical Analysis of Optimizing a Heat Sink and Nanofluid Concentration Used in a Thermoelectric Solar Still: an Economic and Environmental Study

Abstract

In this paper, mathematical modelling is performed for a group of fins in a heat sink in order to determine the optimum dimensionless thickness of the fins using 8 different types of cooling nanofluids including nanoparticles of aluminium, alumina, titanium, titanium dioxide, copper, copper oxide, iron and iron oxide (hematite) with water as the base fluid in a thermoelectric solar still. The heat sink is used to enhance thermoelectric cooling and heating to water. The flow crossing fins is considered laminar and fully developed. Copper with high thermal conductivity is considered as the material of flat plate fins. Different nanofluids with volume fractions of 1%, 3%, 5%, 7% and 9% with a nanoparticle diameter of 25, 50 and 75 nm are analyzed for fins with rectangular cross sections. Besides, the economic and environmental analysis is conducted on the thermoelectric solar still. It is also observed that the range of 3.65% to 3.95% is obtained for the optimum volume fraction in the used nanofluids. The carbon dioxide mitigation based on the environmental parameter and exergoenvironmental parameters in the solar still is about 23.78 tons of CO₂ and 1.04 tons of CO₂, respectively.