Application And Design Method Of Constraint Component In Soft Abrasive Flow Machining

Constraint component, which is the core part in soft abrasive flow machining method, can realize controlling of turbulent flow field according to needs and accom-plish expending and moving of effective machining region. This article presented a design method of constraint component towards soft abrasive flow machining, and completed interrelated confirmatory experiment. The main conclusions are described as follows.(1) Based on solid-liquid two-phase flow boundary layer theory, a mathematical model of trajectory of particle motion was set up to cope with the course of abrasive injection into the wall in the situation of constrained flow passage. To solve the prob-lem of wall contact of light concentration abrasive flow in turbulent condition, a nu-merical method was put forward to calculate injection velocity and angle of free abra-sive. It provided the reliable basis for micro-cutting effect of soft abrasive flow in near-wall region.(2) On the basis of Realizable k-εmodel and Mixture model, a dynamic model of soft abrasive flow machining process was established for concrete condition of con-strained flow passages. Mechanism of asymmetry of dynamic pressure on workpiece surface was revealed by analyzing the structure of eddy to explain the deflection phe-nomenon in circumferential motion of abrasive flow generated by flowing through arc shaped constraint component.(3) A universal design method of constraint component was proposed to meet the demand of soft abrasive flow machining. Based on the experimental platform of soft abrasive flow machining, mobile constraint component was designed and machining experiment was completed. The experimental results show that jut structure of con- straint component has obvious adjustive function to dynamic pressure, volume frac-tion and injection velocity and realizes expending and moving of effective machining region, confirming that the method in this paper is feasible and effective.