Minimum Quantity Lubrication Jet Noise: Passive Control

Jet noise is a common problem in minimum quantity lubrication (MQL) technology. This should be given great attention because of its serious impacts on the physical and mental health operators. In this study, micro-grooved nozzle proposed based reduction concept biological micro-grooves. The flow field acoustic characteristics an original were investigated numerically to help better understand mechanism. reasons for generation effects length (L), width (W) depth (δ) micro-grooves analyzed. It was found that jet generated by large-scale vortex ring structure pressure fluctuations caused motion. overall sound level (OASPL) decreased with increases W δ, increased increase L. Among them, δ has greatest effect reduction. maximum achieved 6.66 dB, as verified OASPL test. Finally, mechanism discussed terms field, vorticity frequency characteristics. Micro-grooves can enhance mixing airflow inside accelerate process vortices breaking into smaller-scale vortices. also reduces (SPL) middle frequencies, well SPL high frequencies specific angles.