Computational Fluid Dynamics Simulation on Thermal Performance of Al/Al₂O₃/SWCNT Nanocoolants for Turning Operations

Abstract

The objective of this study is to numerically investigate the thermal performance of cutting fluids dispersed with nanoparticles for effective heat removal during turning operations. The simulations are performed using Ansys Fluent software, and the problem is modelled as a three-dimensional turbulent incompressible single-phase flow. The computational domain consists of a heated cutting tool and work piece, and nanocoolants are sprayed from a nozzle located above the machining zone. The nanocoolants are prepared by mixing mineral oil with nanoparticles of Al2O3 (Aluminium Oxide), Al (Aluminium) and SWCNT (Single Walled Carbon Nanotube). The heat transfer performances of different nanocoolants are compared by varying the nanoparticle volume fraction (φ) and coolant velocity (Uc) in the range of 2% ≤ φ ≤ 8% and 1 m/s ≤ Uc ≤ 15 m/s, respectively. The results indicated a drastic drop in the cutting tool temperature with an increase in the volume fraction of dispersed nanoparticles and coolant velocity. The increase in volume fraction decreases the average cutting tool temperature by 25.65% and also enhances the average heat transfer rate by 25.43%. It is additionally observed that SWCNT nanocoolants exhibited a superior thermal performance and heat removal rate compared with Al and Al2O3 nanocoolants. The analysed numerical results are validated and are in good accordance with the benchmark results validated from literature.

Keywords

• turning operation
• nanocoolants
• cutting temperature
• cutting fluid velocity
• carbon nanotubes