hypermesh单元质量参数说明VIP专享

Hypermesh 单元质量参数说明 网格质量 中文名 推荐取值 物理意义 Help 原文 2D 单元质量参数 Aspect(ratio) 长宽比 必须小于5:1 单元最长边与最短边（或最短对角节点距离）之比。3D 单元的每个面被看做一个2D 单元并且计算长宽比。最大的长宽比作为3D 单元的长宽比。 This is the ratio of the longest edge of an element to either its shortest edge or the shortest distance from a corner node to the opposing edge ("height to closest node"). HyperMesh uses the same method used for length (min) described below. For 3-D elements, each face of the element is treated as a 2-D element and its aspect ratio determined. The largest aspect ratio among these faces is returned as the 3-D element’s aspect ratio. Aspect ratios should rarely exceed 5:1 Chord dev 弦长偏差 — 圆弧可以大量短直线模拟，弦长偏差是圆弧与直线的垂直距离。 Curved surfaces can be approximated by using many short lines instead of a true curve. Chordal deviation is the perpendicular distance between the actual curve and the approximating line segments. Interior Angles 内角 — 检查三角形与四边形最大与最小角 These maximum and minimum values are evaluated independently for triangles and quadrilaterals. Jacobian 雅克比 理想值1 大于0 .7可接受，质量较好， 小于0.5，准确性不能保证 jacobian 值是衡量网格质量好坏的一个重要指标。数学上 Jacobian 是进行坐标变换的Jacob 矩阵的行列式|J|，它 的取值可以在 [-∞,+∞] 变 化 。Abs(|J|)>1 说明面积扩大，abs(|J|)<1说明面积缩小。|J|<0 说明组成微元的两个向量所称的角的sin 值发生了符号变化(比如从锐角变成钝角)。 HM 中所谓的Jacobian 并不是上面讲的数学意义上的Jacobian，而是在自然坐标(s,t)中的微元向量dS,dT (在自然坐标中成 90 度)， 对应在全局坐标中的向量dS’, dT’所成角度的sin 值。 它只体现了’变形’，而没有体现面积This measures the deviation of an element from its ideal or "perfect" shape, such as a triangle’s deviatio...