Research On Particles In Soft Abrasive Flow Colliding With The Structural Surface

In the structural flow passage, the solid-liquid flow is in a turbulent state, thus the particles in the solid-liquid flow will collide with other particles and the processing wall frequently. The particles of various size and speed direction act on the processing wall randomly, achieving accurate polishing by solid-liquid flow without tools. The cutting action of particles and the multi-particle’s dynamic characteristics in the structural flow passage have guiding significance for specular level processing using the solid-liquid flow. The the processing effect of the solid-liquid flow is reflected by the particle group in macroscopic. A reaching method was put forward to observe the effect of single particle colliding with the processing wall. By the thorough research of the single particle colliding with the processing wall in microcosmic, the scientific nature and feasibility of the accurate processing method and simulation effects by the particle group in macroscopic using the solid-liquid flow without tools ware verified. The main work is as follows:1. Theoretical study on the solid-liquid flow:The solid-liquid flow is a weak adhesive soft abrasive flow, based on the solid-liquid flow and the particle dynamics model, first the single-particle dynamics model was analyzed, and the physical model of the single particle colliding with processing wall was established. Then the motion and force of single particle colliding with processing wall was analyzed. At last, the material removal mechanism of single particle colliding with processing wall was described using hard sphere model and PRESTON removal model.2. Numerical simulation of single particle colliding with processing wall within the solid-liquid flow:According to particle movement when colliding with the processing wall, the physical model of particles colliding with the processing wall was builded. By using ABAQUE software, the processing wall’s force condition and the particle’s energy change were simulated and analyzed, as well as the cutting effect of different kind of particles colliding with the processing wall.3. Based on the study of single particle colliding with the processing wall in microcosmic, the solid-liquid flow dynamics model was established using achievable k-ε turbulence model and discrete phase model (DPM). In the jagged flow passage, the solid-liquid flow was simulated with FLUENT software. Then the particle group’s dynamic pressure with its distribution, particle velocity vector and turbulent kinetic energy changes were obtained, proving the validity of the accurate processing method using the solid-liquid flow.4. Based on the result that described above, the solid-liquid flow observation platform was builded with particle image visualization system(PIV) to observe particle movements. The mutual correlation theory was applied to analyze particle movement and vorticity characteristics, verifying the accuracy of the numerical simulation. According to PIV observation experiment, real workpieces were machined in the jagged flow passage.