Role of Eco-Friendly Bio-Based Graphene-Oil Nanofluids on Friction Reduction for Wind Turbine Application

Abstract

Sustainable energy such as wind turbine is known as a green technology that minimize the carbon emission into environment. However, unwanted friction and wear in journal bearing of a wind turbine's gearbox leads to reduction of power efficiency and increase the reliance onto fossil-fuel powered electricity. Lubricating oils are used in journal bearing to provide the hydrodynamic lubrication film. However, commercially available lubricants are petroleum-based, which are non-replenishable and toxic. Thus, the bio-degradable vegetable oil, high oleic palm oil-based methyl ester (high oleic POME) was used as a base oil synthesized with graphene nanoplatelets (GNP), multi-walled carbon nanotubes (MWCNT) and nanostructured graphite (NSG), respectively, to enhance the friction and wear reduction. The tribological performance of each type of bio-based graphene-oil nanofluid was studied using pin-on-ring tribo-tester. It is concluded that NSG in high oleic POME shows 52.03% friction coefficient reduction and 59.27% pin specimen weight loss reduction. With this significant friction and wear reduction, power efficiency of wind turbine will be improved significantly. Thus, the reliance of society depending on fossil-fuel powered electricity can be reduced and minimize the carbon emission into the environment.