Palm Oil as a Heat Transfer Medium A Numerical Study with Nanoparticle Enhancements

Palm oil plants are abundantly available in Malaysia and are harvested commercially to either be exported in their crude form or used as a base for products such as soap and cooking oil. However, palm oil has also invoked interest in being used as a coolant. As opposed to conventional coolants, vegetable-based coolants such as palm oil offer several advantages, such as being more environmentally friendly upon disposal and safer for users as they are less chemically reactive. It is an accepted hypothesis that the inclusion of nanoparticles would generally increase the heat transfer rate of most fluids as these nanoparticles contribute to a rise in the heat transfer area. This paper presents a numerical study on using palm oil as a medium for heat transfer in machining operations, with and without the use of nanoparticles. It presents heat transfer comparisons between palm oil, conventional water and mineral oil coolants. It was found that the inclusion of nanoparticles increases the heat transfer capability of mineral oil and palm oil with palm oil being more positively affected. However, there is no apparent trend or correlation that can be made between concentration and heat transfer as the percentage increase of the surface heat flux and heat transfer coefficient are inconsistent with the 2% concentration showing a higher percentage increase compared to the 1% and 3% concentrations. Considering the results of this preliminary study, it can be concluded that palm oil together with nanoparticles does present a promising prospect as a coolant.