
Particle simulation with ROCKY DEM for the immersed tumbling process
Sector: Machinery and plant engineeringSpecialist field: Discrete Particle SimulationsMachining processes are being analyzed at the Technical University of Berlin. The process design of immersed tumbling has been optimized with ROCKY DEM using simulations.
Summary
Task
At the Institute of Machine Tools and Manufacturing Technology of the Technical University of Berlin, the process design for immersed tumbling was of interest. Using simulation, suitable finishing media are to be evaluated according to the machining task before the experimental tests.
Solution
ROCKY DEM software can be used to simulate both spherical and non-spherical particles and their interaction with any CAD model.
Customer benefits
The realistic representation of the aspheric finishing media in ROCKY DEM means that even complex tasks can be simulated realistically and significantly faster than before.
Project Details
Task
In the production of micro components and components with the highest demands on surface quality, finishing plays a particularly important role. Immersed tumbling is a widely used process for the deburring, polishing and edge rounding of components. In this process, chip removal is achieved inside a container filled with finishing media by the relative movement between abrasive media and workpieces. To achieve the desired workpiece quality, the process is carried out in several stages. At the Institute for Machine Tools and Manufacturing Technology of the Technical University of Berlin, various cutting and machining processes are being analyzed in terms of process technology and numerically within the context of basic research. A current focus is the targeted, simulative process design for immersed tumbling using the ROCKY DEM software. This makes it possible, for example, to evaluate suitable finishing media for the machining task before the experimental tests.

Customer Benefit
The realistic representation of the aspheric finishing media in ROCKY DEM means that even complex tasks can be simulated realistically. Compared to previously used open source programs, the calculations are many times faster thanks to the systematically supported GPU acceleration. This allows optimizations to be made to the structure while the process is still being planned, as well as the collection of various data on the expected results. The Institute of Machine Tools and Manufacturing Technology of TU BERLIN plans to use ROCKY for modeling further manufacturing processes, such as the immersed tumbling process.

Solution
The ROCKY DEM software can be used to simulate both spherical and non-spherical particles and their interaction with any CAD model. The complex particles are defined here by their actual, multi-faceted shape and not by means of bonded spheres. The influence of the differently shaped particles is to be demonstrated with a test scenario in which a sample workpiece is passed through a basin with variously shaped finishing media in four tests. The finishing media used have the shape of spheres, cones, tetrahedrons or triangular prisms. There are clear differences in the expression of the mean normal stress. These differences, which depend on the shape of the finishing media, correspond qualitatively with the contact situations visualized in the figure as well as with real results that were obtained in experiments at the Institute of Machine Tools and Manufacturing Technology of TU Berlin.
Images: © TU Berlin
