冶金工程中映射网格划分技巧(5)

冶金工程中映射网格划分技巧

S in this direction, the results as shown in figure 4. In the process of discrete number to the node and assign, by the way its coordinates, node numbering principle is commonly from left to right, from down to up (numbering is different from ansys). Then give unit number assignment, node, material etc.), and press from left to right, from down to up number increasing. As the fifth unit of node Numbers for 7,8,11,10 (generally assign node according to the clockwise or counterclockwise order number), unit of node numbering is regular can be achieved by

program. This completes a four node mapping grid below, then press the same steps to hold 2, 3,... A plane, but check for node superposition.

对于三角形单元，可以先划分成四边形单元，然后按单元数循环，将每个四边形单元划分成两个三角形单元。举例如下：

For i=1:1:en

Nn=elem.node{i};

Elem.nodetri{2*i-1}=[Nn(1) Nn(2) Nn(3)];

Elem.nodetri{2*i}=[Nn(3) Nn(4) Nn(1)];

End

以上是MATLAB语言，进行以上操作以后就可以得到2en个三角形单元，单元的节点编号存放在Elem.nodetri中。

Above is the MATLAB language, after above operation can get 2 en triangle unit, unit node number in Elem. Nodetri.

对于8节点等二次单元可以在四节点单元的基础上，在各单元边中分别产生一个节点，节点坐标即两个节点坐标的平均值。

For eight nodes and other secondary units can be on the basis of the four node unit, respectively in each unit of a node, the node coordinates, the coordinates, the average of the two nodes.

如果组成平面的边有圆弧则按柱坐标离散，然后再转换成直角坐标，但要考虑圆弧所在象限的问题。如果是其他曲线则须给出曲线方程……

If of flat edge arc is discrete in cylindrical coordinates, and then converted into rectangular coordinates, but want to consider the problem of circular arc in the quadrant. If it is other curve must curve equation is given...

如果是三角形，可以先将其分割成3个四边形，然后按上诉方法离散。分割的方式与划分数的设置有关（如图5）。从图5可以看出三角形映射网格划分需要满足的划分数匹配条件：

If it is a triangle, can first to split it into 3 a quadrilateral, then according to the discrete appeal method. Segmentation approach is associated with the setting of partition number (as shown in figure 5). Can be seen from figure 5 triangle mesh mapping division number matching conditions to be met:

1）有两条边的划分数相等；

1) there are two side of the partition number is equal;

2）第三条边的划分数必须为偶数；

2) the third side of the partition number must be an even number;

3）第三条边的划分数必须小于另外两条边的划分数的2倍-2。

3) the third side of the partition number must be smaller than the other two side of the partition number 2 x - 2.

在ansys里还有其他条件，比如图6的划分数在ansys里是不能进行映射网