ansys中单元质量问题(国外英文资料).doc

ansys中单元质量问题(国外英文资料) Mesh is the basis of finite element analysis. In order to ensure the accuracy of analysis results, the quality of grid must be guaranteed first. ANSYS will check the quality of the grid and give warning or error messages to the units that have quality problems. If a quality index unit over / less than a given value, will give a warning (warning message), if the quality index than / less than a given value, will give you an error message (error message), if there is a warning, it is still possible to calculate it, just the calculation accuracy may be affected (probably, the specific circumstances require specific analysis). If there is an error message, the calculation is usually not going to go on. In ANSYS, the quality of measurement units mainly has the following indexes: 1.Aspect Ratio: aspect ratio. That is, the ratio of the longest and the shortest sides of the cell. When aspect ratio is more than 20, ANSYS will give warning information, and when more than 1.0e6, it will give wrong information. Usually when we divide the grid, to ensure that the unit length width ratio should not exceed 5~10, if the situation is special, it is best not to exceed the ANSYS warning value is 20, then step back, length width ratio is more than 20, we must ensure that the number of such units is relatively small, but the number is more than 20 not too otherwise, the results very low credibility. 2.Deviation, From 90, Degree, Corner, Angle:, chordal difference. This is for the face element. When there is a chamfer in the structure, the number of mesh layers at the chamfer is higher, and the higher the degree of agreement between the element and geometry, the better the chord difference index at this time. Conversely, the fewer the number of chamfer layers, the farther the unit deviates from the geometry, the worse the string difference. As for how ANSYS mathematically defines string differences, there is no way to know. This indicator we usually pay less attenti