This paper discusses flow characteristics of nanofluid minimum quantity lubrication (MQL) in the milling process of a titanium alloy by usingnumerical analysis. A mist of nanofluids including nanodiamond and hexagonal boron nitride (hBN) particles is sprayed into a tool-workpiece interface with conditions varying by spray angle and flow rate. The milling. Are experimentally measured and minimized by the determined optimal spray angle and flow rate. The subsequent numerical analysis based on a computational fluid dynamics (CFD) approach is conducted to calculate the penetration ratios of the nanofluid droplets into a tool. At the experimentally obtained optimal spray angle and flow rate of the nanofluids’ mist, the calculated ratio of penetration is highest and, therefore, the optimal spray conditions of the nanofluids are numerically validated.

This paper presents a numerical study on the thermal characteristics of a milling process of titanium alloy with nanofluid minimum-quantity lubrication (MQL). The computational fluid dynamics (CFD) approach is introduced for establishing the numerical model for the nanofluid MQL milling process, and estimated temperatures for pure MQL and for nanofluid MQL using both hexagonal boron nitride (hBN) and nanodiamond particles are compared with the temperatures measured by thermocouples in the titanium alloy workpiece. The estimated workpiece temperatures are similar to experimental ones, and the model is validated.