| Gas-Liquid-Solid three phase abrasive flow polishing(GLSP) is a new method for machining large area workspace surface by using high speed swirling Gas-Liquid-Solid three phase abrasive flow in turbulent state. Through the numerical simulation of the abrasive flow field characterstic under different incident angle of abrasive flow, the motion law of abrasive flow are studied, and the best structural design parameters are obtained. Based on the simulation result, the experimental setup are built. The main contents are shown as following:(1) In order to solve the precision manufacturing problem for large flat surface of the optical and semiconductor, the existing machining method are investigated and the advantage of abrasive flow polishing are indicated. The development, advantages and disadvantages of current abrasive flow polishing methods are reviewed, and a new method of GLSP was proposed based on the theory of of the microscopic bubbles collapsing.(2) Based on the Realizable k- ε turbulence model and Mixture model, an analysis model of GLSP process was established. Through the numerical simulation of the abrasive flow field characterstic under different incident angles of abrasive flow incident angle, the motion law of abrasive flow are studied, and the best structural design parameters are obtained, which provides the guidance for the polishing tool design.(3) The experimental setup is built, and the appropriate abrasive flow ratio and process plans are selected based on the numerical simulation. The comparative experiments of GLSP with microscopic bubbles, millimeter bubbles, and Liquid-Solid two phase abrasive flow polishing are conducted respectively. The results show that in the GLSP with microscopic bubbles, the collapsing of the microscopic bubbles will promote the abrasive speed in the high speed swirling flow field, the machining efficiency and the surface roughness and uniformity after 10 h machining are the best. |
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