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1. Moisture-controlled triboelectrification during coffee grinding

   https://doi.org/10.1016/j.matt.2023.11.005  

   Méndez_Harper, Joshua; McDonald, Connor S; Rheingold, Elias J; Wehn, Lena C; Bumbaugh, Robin E; Cope, Elana J; Lindberg, Leif E; Pham, Justin; Kim, Yong-Hyun; Dufek, Josef; et al (January 2024, Matter)
2. Strategies to mitigate electrostatic charging during coffee grinding

   https://doi.org/10.1016/j.isci.2024.110639  

   Harper, Joshua Méndez; Bumbaugh, Robin E; Hendon, Christopher H (September 2024, iScience)
3. Liquid Coolant Jet Breakup with Application to Grinding

   https://doi.org/10.2514/6.2024-85879  

   Sakib, Sheikh Ahmad; Povitsky, Alex (January 2024, American Institute of Aeronautics and Astronautics)

   Liquid jets in surrounding air face capillary and shear forces which eventually disintegrate the jet into droplets or spray. The instabilities developed in the flow inevitably break down an initial laminar (coherent) jet into a turbulent one. In the manufacturing process called grinding, one of the oldest approaches of shaping metals and other materials, liquid coolant jets are frequently used. A non-coherent or turbulent jet has a reduced flow rate due to cavitation, air entrapment and atomization of the fluid particles. The jet spread does not allow the coolant jet to effectively breach the high-speed rotating air layer, created by entrainment of air along the surface of rapidly rotating grinding wheel. The coherent, nearly columnal jet should be sufficiently long to maintain its initial velocity to penetrate the layer of air rotating with the grinding wheel. Thus, in many critical grinding applications, it is advised to use a coherent jet instead of a spray to eradicate defects of ground surface. In this study, we present simulations of liquid jet flows to see how the jet develops and breaks due to surface tension and shear forces. Creating an accurate model to predict liquid jet characteristics, especially for high-speed applications such as grinding wheel cooling would require wellresolving numerical grids and turbulence model selection. The problem being multi-phased with a density ratio of coolant-to-air being order of 1000 adds to the computational complexity. The presented numerical model and results are different compared to the previous simulations of liquid jets as the characteristics of jet disintegration are explored under conditions that closely resemble a grinding cooling application. Finite volume discretization of the flow domain and calculation of flow field characteristics were done by commercial software ANSYS Mesh and ANSYS Fluent modules, respectively. The numerical calculation and visualization of disintegration of free jet and the jet impinging into grinding wheel will be presented. 

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4. Reusable unit process life cycle inventory for manufacturing: grinding

   https://doi.org/10.1007/s11740-017-0768-x  

   Linke, Barbara; Overcash, Michael (December 2017, Production Engineering)

   null (Ed.)
5. Grinding of silicon carbide for optical surface fabrication, Part 1: surface analysis

   https://doi.org/10.1364/AO.455863  

   Shanmugam, Prithiviraj; Lambropoulos, John_C; Davies, Matthew_A (May 2022, Applied Optics)

   This paper presents a study of the grinding of three different grades of silicon carbide (SiC) under the same conditions. Surface topography is analyzed using coherent scanning interferometry and scanning electron microscopy. The study provides a baseline understanding of the process mechanics and targets effective selection of process parameters for grinding SiC optics with near optical level surface roughness, thus reducing the need for post-polishing. Samples are raster and spiral ground on conventional precision machines with metal and copper-resin bonded wheels under rough, medium, and finish grinding conditions. Material microstructure and grinding conditions affect attainable surface roughness. Local surface roughness of less than 3 nm RMS was attained in both chemical vapor deposition (CVD) and chemical vapor composite (CVC) SiC. The tool footprint is suitable for sub-aperture machining of a large freeform optics possibly without the need for surface finish correction by post-polishing. Subsurface damage will be assessed in Part 2 of this paper series. 

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