Wet machining is commonly performed for various processes and material combinations. It requires a large amount of metal working fluid (MWF) to be continuously introduced onto the workpiece and tool. One of the primary disadvantages of using MWF is the large amount of MWF mist generated during the machining process.; Current air quality strategies, including conventional and alternative approaches, fall short on their effectiveness in thoroughly removing the harmful mist generated. Motivation to develop a control strategy, which effectively removes and reduces airborne MWF mist, arises. The study of mist formation and behavior yielded the development of a droplet generation and droplet behavioral models. The droplet generation model reported three main droplet generation mechanisms, while droplet behavioral model addressed the settling and evaporation mechanisms after droplets were generated. Experimental and analytical findings made during the studies, discovered the potential of removing fine MWF droplets using a kinematic coagulation mechanism. The potential of developing a new control strategy for MWF mist removal using a kinematic coagulation mechanism was investigated from three different aspects, namely the experimental, analytical and computational aspects. The plan was to explore the potential of using a kinematic coagulation mechanism, by introducing larger artificially generated MWF droplets to the fine MWF mist.; A CFD study was conducted to simulate the droplet coagulation phenomena in the wet turning process within an experimental enclosure environment. The commercial CFD software Star-CD was selected for use in the CFD study. The capability of the software in simulating droplet coagulation was tested. The enclosure environment used during the experimental study was modeled, and the airflow effect induced by the workpiece rotation onto the fine MWF mist was also studied. The initial plan for the CFD study was to construct a single transient model, simulating droplet generation, settling, and coagulation. Changes were made during the study in response to the findings made and limitation of the computational resources. Separate steady state simulations were performed to study the droplet generation and droplet settling processes. The specification of the droplet generation was based on the atomization model developed. A series of transient simulations were performed to test the effect of the different droplet parameters on the level of droplet coagulation. (Abstract shortened by UMI.)
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