Experimental and Numerical Investigation of the Dispersion of Microparticles Emitted by Machining Operation

As a part of the development of a numerical method of close capture exhausts systems for machining devices, a test rig recreating a situation similar to a grinding operation, but in a perfectly controlled environment, is used. The properties of the obtained spray of solid particles are initially characterized using particle tracking velocimetry (PTV), in order to obtain input and validation parameters for numerical simulations. The dispersion of a tracer gas (SF6) emitted simultaneously with the particle jet is then studied experimentally, as the dispersion of such a gas is representative of that of finer particles, whose aerodynamic response time is negligible. Finally, complete modeling of the test rig is achieved to allow comparison with experimental results and thus to progress towards validation of the models used to describe a twophase flow generated by machining operation.

Authors:

• F. Tafnout
• E. Belut
• B. Oesterlé
• J.R. Fontaine

Keywords:

• Pollutants
• capture
• tracer gas
• SF6
• PTV
• numericalmodeling.

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