Media Flow Analysis of Single-Channel Pre-Mixed Liquid CO2 and MQL in Sustainable Machining

Single-channel supply of pre-mixed liquid carbon dioxide (LCO2) and minimum quantity lubrication (MQL) represents a state-of-the-art LCO2 assisted machining. However, to fully understand optimize cooling provided by the + MQL, fundamental media flow analysis is essential, yet not researched enough. Therefore, in this paper, velocity oil droplet size were analysed supplying line at nozzle outlet using high-speed camera proprietary single-channel system. Results indicate that mainly influenced expansion rate upon outlet, wherein largely dependent on solubility between LCO2. Media increases significantly from an average 40 m/s excess 90 due pressure drop expansion. Furthermore, volume causes increase point critical, unstable size. Afterward, breaks up into smaller droplets. It was found, nonpolar oil, with greater LCO2, compared polar provides droplets as small 2 μm diameter. Smaller positively reflect tool wear life machining, longest achieved for MQL.