Computational Fluid Dynamic Analysis of Coolant Flow in Milling of Titanium grade-2 under Multiple Nozzle

Abstract

The application and behaviour of coolant in end milling of hard-to-cut material such as titanium alloy is very critical due to the high cutting temperature generated at the tool tip that can be more than 600°C. Titanium is generally well known to have a very low thermal conductivity that prevent a rapid dissipation of the heat generated during machining due to the friction that occur in the metal removal process. In addition, hard-to-cut material have a very high hardness that can range from 198 to 1300 HV at Vickers hardness. For all this reasons, the optimization of the coolant that includes positioning, inclination and distance of the nozzle to the tool tip is very vital to provide an efficient cooling during the machining operation. In this paper, a three dimensional static analysis of the application of coolant through two nozzles was studied by using computational fluid dynamics (CFD). It was found that the velocity of the coolant was more uniformly distributed and effective when two nozzles were applied at an angle of 12.5 º and a distance of 25 mm from the tool tip.