In another study on engine oil containing 1.0% volume
carbon nanotube, 160% enhancement in thermal conductivity was
observed by Choi. Nanofluid minimum quantity lubrication
(MQL), which has been recently mentioned, was investigated by Nam. They found that using nanofluid MQL in micro drilling
process decreases the drilling torques and thrust forces.Many studies
have been carried out about the effect of nanofluids on convective
heat transfer coefficient and friction factor . Sundar
reported the enhancement of convective heat transfer coefficient and
friction factor by adding Fe3O4 nanoparticles to water.Duangth-
ongsuk and Wongwises stated that water nanofluid consisting of
0.2%volumeTiO2 nanoparticles caused 6–11% enhancement in the
heat transfer coefficient.