Water jet guided high-power laser energy transmission loss analysis

Water jet-guided laser is a novel machining technique. With the continuous emergence of high-hardness, high-strength materials and the increasing demand for efficient processing, the coupling of waterjet with high-power lasers has become an inevitable trend in developing water-guided lasers. However, the coupling and transmission of high-power laser energy with a water jet during the processing process introduce a series of issues, including transmission losses, which will emerge as crucial challenges limiting the development of this technology. Therefore, it is imperative to investigate the transmission losses of high-power laser energy guided by water jets. This study addresses this issue by employing the finite element method (FEM) to solve Maxwell's equations numerically, conducting wave optics simulations of the propagation of high-power lasers in water jets, and obtaining the electric field distribution of the laser beam within the water jet. Simultaneously, an investigation into the relationship between different laser beam diameters, waterjet diameters, lengths, and the energy loss of the laser is conducted to analyze the transmission losses of high-power lasers in waterjets. Finally, transmission efficiency measurements of laser coupled with a water jet are conducted utilizing a self-designed water-guided laser experimental platform. The effectiveness of the model is validated by comparing experimental results with simulations. The research findings will provide valuable insights into regulating the transmission efficiency of high-power lasers within water jets.