the characteristic element size

杜子腾

今天看K文件里有the characteristic element size这个短语，翻译过来是“特征单元尺寸”，可是请问这是何意呀，指的是什么了，请求大侠指教。

lojade

abaqus中关于the characteristic length的定义和作用，可以借鉴一下。
The definition of the characteristic length depends on the element geometry and formulation: it is a typical length of a line across an element for a first-order element; it is half of the same typical length for a second-order element. For beams and trusses it is a characteristic length along the element axis. For membranes and shells it is a characteristic length in the reference surface. For axisymmetric elements it is a characteristic length in the r–z plane only. For cohesive elements it is equal to the constitutive thickness. This definition of the characteristic length is used because the direction in which fracture occurs is not known in advance. Therefore, elements with large aspect ratios will have rather different behavior depending on the direction in which they crack: some mesh sensitivity remains because of this effect, and elements that have aspect ratios close to unity are recommended.

Eospearo

warped elements ：

several alternatives can be selected via *CONTROL_TIMESTEP variable ISDO (Control Card 9, Columns 21-30), e.g.:

where β = 0 for quadrilateral and β = 1 for triangular shell elements.

杜子腾

谢谢楼上两位，让我茅塞顿开