Enhancement of heat transfer from solar thermal collector using nanofluid

Abstract

Global energy consumption is increasing due to population growth and with it the adverse impact of fossil fuels on the environment, making it necessary to use renewable energy sources and convert them to electrical energy using different technologies. However, the solar energy potential remains unused, while it has numerous advantages, including as a source of clean electricity and heat. One of the main difficulties in energy-saving and compacted design is how to increase the heat transfer of solar equipment. As an innovative approach to enhancing fluids’ heat transfer performance, some of the most active techniques are to exchange the working fluid with nanofluids. This work attempted to demonstrate heat transfer behavior changes when using nickel oxide (NiO), aluminum oxide (Al2O3), and copper oxide (CuO) as nanofluids at concentration volumes of 0.05, 0.075, and 0.1%. For this goal, a conical solar collector was built using local public steel sheets. Insulating polyurethane foam padding is used inside the cone. The sun’s energy is focused on the absorbing surface using thin reflective aluminum foil. The study also includes a literature review showing how nanofluids can improve heat transfer in solar collectors. The results showed that adding nanoparticles can increase the rate of heat transfer and CuO nanofluids have better augmentation in heat transfer than Al2O3 or NiO-water nanofluids where 1% CuO nanofluids increases the efficiency by up to 7% compared to water.

Keywords

• augmentation
• nanofluid
• solar energy
• solar collector
• thermal fluid