Numerical investigation of thermal characteristics of spray cooling with minimum quantity lubrication in milling process

This study explores the cooling performance associated with spray cooling with minimum quantity lubrication (MQL) in milling of Ti-6Al-4V using tungsten carbide (WC) cutting tool. Vegetable oil is used as a cutting fluid, and it impacts the cutting zone. A numerical model using sliding mesh and discrete phase model (DPM) is developed to calculate the flow field and the temperature distributions in both WC and Ti-6Al-4V subjected to conjugated heat transfer. The effect of spray angle relative to the feed direction on cooling performance is examined by analyzing the flow field and droplet behavior when nozzle is oriented to the tool or tool flute. The result shows that the temperature of both WC and Ti-6Al-4V for 0 and 90 degrees of spray angle is lower than that for 45 degrees of spray angle. However, 90 of spray angle is not suitable for lubrication purpose in milling process since MQL droplets hardly penetrate into the cutting zone. (C) 2018 Elsevier Inc. All rights reserved.