Study on laser ablation of TC4 for drag reduction groove considering plasma shielding effect

Abstract

Inspired by the structure of shark skin, rib grooves have demonstrated significant potential for drag reduction in applications such as aviation and pipeline transportation. Laser ablation, owing to its high efficiency and cost-effectiveness, when combined with numerical simulations, enables precise control over the groove structure to optimize drag reduction performance. This research develops a predictive model for laser ablation that incorporates the plasma shielding effect, systematically investigating the evolution of surface morphology during the laser ablation of TC4 titanium alloy. The influence of varying laser parameters on groove morphology is analyzed, with the model’s accuracy rigorously validated against experimental data. Building on this foundation, the study further employs the simulation model to establish a quantitative relationship between groove morphology and drag reduction performance. By adjusting laser parameters, the model facilitates rapid and accurate simulation and prediction of optimal groove dimensions for maximum drag reduction, thereby guiding the fabrication of drag-reducing specimens. Experimental results reveal that, in closed-channel tests, the optimal drag reduction is achieved when the groove depth-to-spacing ratio is 0.5, yielding a maximum drag reduction rate of 11.3%. The numerical simulations presented in this study serve as a valuable tool for optimizing laser parameters and predicting the drag reduction capabilities of functional surfaces.