Airflow Analysis Inside and Outside the Nozzle in Shot Peening Process

Surface modification treatments using particle impact, such as shot peening and fine particle peening, are used in many parts such as automotive gears. However, the surface modification effect is affected by many factors such as the material of the projectile, particle size, and nozzle diameter. In the case of the air injection type, the airflow inside and outside the nozzle has a particularly large effect. However, few studies have examined the effects of airflow inside and outside the nozzle. In this study, the airflow inside and outside the nozzle was analyzed using the finite element method. As a result, it was found that the airflow velocity increases as the nozzle diameter increases. It was also clarified that the factors causing this increase were the lengthening of the potential core section and the deceleration caused by the wall resistance.