| Roshaz has powerful state of the art geometry clean up tools to remove slivers and other undesirable artifacts of CAD operations, such as sharp angles which can be partially stitched (sharp V geometry -> softer Y geometry).
Clean up operations are automatic and are controlled by a user defined tolerance setting. They can be applied to the whole model, individual features or a user defined set of features.
If slivers are allowed to remain in the geometry then poor quality elements will be generated by the meshing algorithms and incorrect results may be obtained. For this reason it is recommended that all slivers and other small false geometry features that do not exist on the real product are removed using the clean up tools prior to meshing.
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| Mesh Close-up View |
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| Quality Mesh created from CAD model after geometry clean up procedures have removed small slivers and other undesirable products of CAD boolean operations. Clear Results Presentation
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| Stress on Quarter Piston Model |
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| Making Use of Symmetry and Local Mesh Refinement |
The valve model here was imported as a whole from CAD in the Iges format.
Roshaz split the model along the two planes of symmetry. A quarter of the model was then meshed, had restraints applied, loaded with internal pressure and analysed. The first run clearly shows a "hot spot". The mesh in this region was then quickly and easily refined to enhance the quality and accuracy of results in the re-run.
From import to final analysis took only a few minutes.
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| Analysis of Car Door Latch using Balanced Loads with Minimal Supports |
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| Free Body Diagram showing a Determinate Set of Forces acting on the Latch |
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| Model Mesh used for the Analysis (click to enlarge) |
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| Forces Applied as Realistic Variable Pressures with Minimal (3 - 2 - 1) supports to Prevent Rigid Body Motion |
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| Von Mises Stresses displayed on Exaggerated Deformation |
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The above example shows how unrealistic stresses at rigidly fixed points can be avoided by applying a balanced set of loads and moments. The supports are there merely to prevent rigid body motion and do not react any load. Loading is applied by program and user defined variable pressure patches to best simulate real life conditions. No artificial rigid body elements are necessary, either for loading or restraint. The resultant stress contour fringe plot shows no irregularities at any of the three nodes used for restraint.
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