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回复：（雅马哈）[分享]ansys与 adams
我发个更详细的，但是是错误的，老是报错。希望各位大侠能够指正！！
ansys和ADAMS柔性体转化问题的详细步骤
我使用的是ansys8.0，adams12.0。其实，按照我的做法，在ansys7.0中是可以生成mnf文件的，虽然有warning。但是不知道为什么在8.0中就不可以了。请教各位大侠是否可以指正一下？我疑惑的地方都用红色标出做了注释，谢谢！
1. 导入igs的几何模型
2. 定义两个单元，分别是soild45和mass21。
3. 定义mass21单元的实常数。
4. 定义材料属性，扬式模量和柏松比
5. 定义密度
6. 定义两个关键点，号分别为2000和2001。
7. 将几何实体划分网格。
注意，这里有个问题，就是实常数的设置号为1，但是并不是为它而设的，不知道会不会出现问题。
8. 划分关键点的网格，然后关键点就成为interface node（外部节点）。
这里可能存在问题，就是材料号为1，不知道会不会出现问题。
9. 将外部节点与边界节点耦合，成为刚性区域
这里也存在问题，因为在help里有这样一段话，
You must pay special attention to modeling interface points for these reasons:
• An interface point must have six degrees of freedom (except for 2-D elements).
• Force (applied directly or via a joint) should be applied to the structure by distributing it over an area rather than applying it at a single node.
• If there is no node in the structure where you can apply the force or joint in ADAMS (for example, a pin center), you need to create a geometric location for that point.
Use the following guidelines to determine the best way to model the interface points for your structure:
• To ensure that all your loads will be projected on the deformation modes in the ADAMS simulation, you must define all nodes where you are going to apply a joint or a force as interface points.
• Interface points in ANSYS must always have 6 degrees of freedom, except for 2-D elements. If your model consists of solid elements, use constraint equations or a spider web of beam elements (as shown in Figure 10.1: "Connecting a Structure to an Interface Point") to ensure that the interface node has 6 degrees of freedom.
• A good practice for modeling interface points is to reinforce the area using beam elements or constraint equations. Using one of these techniques will distribute the force over an area rather than applying it to a single node, which would be unrealistic.
• If you use a spider web of beam elements, use a high stiffness and a small mass for the beams. Otherwise, you will alter the stiffness and mass of your model, which could result in eigenmodes and frequencies that do not represent the original model.
• You may use constraint equation commands such as CE and CERIG to attach the interface node (for example, CERIG,MASTE,SLAVE,UXYZ, where MASTE is the interface node). Avoid the RBE3 command since problems can occur with the master degrees of freedom. If you use constraint equations, mesh the interface point with a MASS21 element (use KEYOPT(3) = 0) that has small (negligible) inertias.
• Do not define interface points that lie next to each other and are connected by constraint equations or short beams. This type of connection would require too many eigenmodes and result in a model that is not well conditioned.
Solid elements do not have rotational degrees of freedom. Therefore, moments will not be properly transmitted from the interface point to the structure (a spider web scheme should be used).
10. 完成耦合。
11. 运用adams命令，选择节点。
12. 出现错误。
[ 本帖最后由 yejet 于 2006-9-11 16:12 编辑 ] |
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发表于 2006-6-12 09:52
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