Thermal-Fluid-Solid Coupling Simulation and Cooling Optimisation of Milled Aluminium Alloy Based on CEL Approach

In high-speed milling, cutting parameters and coolant flow rate significantly impact the temperature and residual stress distribution of the workpiece, thereby affecting machining quality and tool life. This study employs finite element simulation to investigate the influence of feed rate, spindle speed, milling depth, and coolant flow rate on maximum cutting temperature and residual stress. A three-dimensional thermal-fluid-solid coupling mechanical simulation model was established, utilizing explicit dynamics analysis to simulate the milling process. The results indicate that increasing the feed rate raises temperature, while the increase in shear angle and thermal softening effect reduces internal stress, which in turn improves material plastic deformation capability. Higher spindle speeds aid heat dissipation, reducing both temperature and residual stress, whereas greater milling depths significantly increase mechanical load, leading to higher temperature and residual stress. Analysis of coolant flow rate reveals that lower flow rates offer limited cooling, while higher flow rates significantly enhance heat dissipation efficiency, drastically reducing temperature. Meanwhile, the distribution of residual stress varies nonlinearly with coolant flow rate, indicating the significant impact of thermal gradient distribution. These findings provide critical references for optimizing milling parameters and cooling strategies, contributing to improved machining efficiency, reduced thermal load, and prolonged tool life.