关键词: 振动光整加工, 空间过渡型腔, 离散元模拟, 姿态控制, 表面粗糙度

Abstract: The slender internal tubes within the cavity of the casting cavity are an important component of the complex cavity of the integral casting cavity. The internal connection methods are complex and diverse,and the dimensions vary. The distribution of normal force is a key factor affecting the consistency of running and grinding of the complex cavity of the integral casting cavity. Aiming at the grinding processing problem of the spatial transition cavity in the integral casting cavity of aero engines,based on the vibration grinding process in a confined space,a method combining discrete element simulation and experimental verification was adopted to systematically study the influence of the spatial attitude of the elbow tube cavity on the normal force distribution of the granular medium and the grinding effect. Through EDEM simulation,the distribution law of particle contact force under different azimuth angles φ and polar angles θ was analyzed,and the optimal processing attitude range was determined as φ≥60°,θ∈[120°,150°]. Under this condition,the effective grinding area ratio exceeded 60 %,significantly increasing the effective normal force distribution range. The experimental results show that when the vibration parameters are a frequency of 50 Hz and an amplitude of 2.5 mm,the surface roughness Ra can be reduced from the initial 4.93 μm to 2.01 μm after 90 minutes of processing at the optimal attitude,with a surface roughness reduction rate of 59 %. The research shows that when the cavity is in the optimized spatial orientation, normal collisions dominate the material removal, optimizing the particle distribution.

Key words: vibration finishing, spatial transition cavity, discrete element simulation, attitude control, surface roughness