当前位置:首页 >> 机械/仪表 >>

Femap网格划分 及交互式网格修改


Femap 网格划分 及交互式网格修改
Table of Contents
Overview and Setup ...................................................................................................................................... 1 Accessing the Model ..................................................................................................................................... 2 Setting the Mesh Sizes .................................................................................................................................. 2 Meshing the Model ....................................................................................................................................... 4 Interactively Refining the Mesh .................................................................................................................... 6

Overview and Setup
The geometry model for this demonstration is a Femap model file which is based on a Parasolid model of a thin-walled sheet metal part. This model was previously imported into Femap and mid-planes were extracted to create a surface geometry model. The intention of this demonstration is to show how finite element mesh setup, meshing and interactive mesh editing can be applied to create a high quality FE model that will yield accurate results.

As much use as possible has been made of the Model Info tree, toolbars and icons in the user interface to access Femap’s functionality. Usually there is more than one approach that can be employed for any given command. Note that the Parasolid model file was created using millimeters as the unit of length. All references to length in this demonstration therefore are in millimeters.

To ensure that you have all of the necessary icons displayed, a standard layout should be loaded using the Load layout command: Select File Preferences In the Toolbars section of the User Interface tab, select the Load Layout button In the Load Layout From dialog, browse to the workshop directory and select the Workshop.layout file, and click Open and OK

Accessing the Model
Open the Femap model file from the workshop directory Select File Open or select the File Open icon on the Model toolbar, and browse for the Femap model file Femap_BracketMesh_Start.modfem(此文件可从 QQ 群 199022551 下载) – this model file already has some geometry modifications in readiness for meshing

Setting the Mesh Sizes
In this section we’ll activate mesh markers and count, set a default mesh size, override the default by setting a mesh size on surfaces (this activates the count), and set particular mesh sizes for the three washer offset curves on the model. Make sure that the Mesh Size markers are switched on by selecting the drop menu right arrow of the View Style icon in the View toolbar – verify that the Mesh Size icon

is activated in the drop down menu Select View / Options or click the F6 shortcut key and in the View Options dialog within the Labels, Entities and Color category, select Curve – Mesh Size in the Options area In the Show As area of the View Options dialog, select 3..Symbols and Count and click OK Select Mesh / Mesh Control / Default Size and enter a Size of 5. and click OK Select Mesh / Mesh Control / Size on Surface or click on the Mesh Size on Surface icon in the Mesh toolbar In the Entity Select dialog click Select All and OK In the Automatic Mesh Sizing dialog, enter 6.25 for the Elements Size and click OK and Cancel

-

Zoom into the area that contains the three washer offset curves at the front of the model by selecting the Zoom icon in the View toolbar

-

Select Mesh / Mesh Control / Size Along Curve or click on the Mesh Size on Curve icon on the Mesh toolbar, in the Entity Selection dialog select all of the washer offset semi-circular curves and the curves around each of the three holes, verify selection by clicking on the Selection Highlight icon , and click OK

-

Enter 6 for the Number of Elements in the Mesh Size Along Curves dialog and click OK Back in the Entity Selection dialog, select all of the split curves for each of the three holes, and click OK Enter 2 for the Number of Elements in the Mesh Size Along Curves dialog, and click OK and Cancel

-

Select the Previous Zoom icon

on the View toolbar

Meshing the Model
With the preparatory work finished, the next task is to mesh the model.

-

Select Mesh / Geometry / Surface or click on the Mesh Surface icon toolbar In the Entity Selection dialog, click Select All and OK

on the Mesh

-

In the Automesh Surfaces dialog click the Define Property icon In the Define Property dialog click the Define Material icon In the Define Material dialog click the Load button and the Choose Library button

-

Browse to install_directory/femap11/mat_eng_mm-N-tonne-degC-Watts.esp, select and click Open Select 16-25-6 Stainless Steel and click OK

-

Click OK to accept the material definition In the Define Property dialog enter 1.981 for the thickness and click OK In the Automesh Surfaces dialog click OK and the finite element mesh will be created

Interactively Refining the Mesh
Now that the model has been meshed we’ll use the Meshing Toolbox with live element quality checking to verify that the mesh settings defined previously have created as desired and we’ll make some further mesh adjustments interactively. In particular we’ll suppress a hole, merge some split curves and tidy up the mesh using the Mesh Sizing and Mesh Locate capabilities within the Meshing Toolbox. Activate the Meshing Toolbox by clicking the Meshing Toolbox icon Select the Mesh Quality tool in the Panes toolbar

Click on the Quality icon in the header line of icons in the Meshing Toolbox pane Click on the down arrow next to Quality Type Jacobian in the Mesh Quality tool to show that other quality checks are available Expand the tool next to Jacobian by clicking the + sign and set the Max Allowable Value to 0.8 (a more reasonable value for a Jacobian check)

-

Select the Zoom icon in the View toolbar and zoom into the area of the model with the three holes with washer offset curves for which preset curve mesh sizes were set

-

Select the Previous Zoom icon on the View toolbar then select the Zoom icon again and zoom into the area of the model to the right that contained the flange with the pad

-

Select the Previous Zoom icon Select the Zoom icon

on the View toolbar to return to the full model view

in the View toolbar and zoom into the area of the model to the left

-

Click on the Feature Suppression tool in the Meshing Toolbox dialog

-

In the header icons of the Meshing Toolbox select the down arrow next to the Remesh Tools icon and select Auto Remesh

-

Select the Select icon (next to Auto Remesh) To suppress the hole in the flange select both of the defining curves, the hole should disappear and the model remesh automatically, however the defining curves will remain as the hole has only been suppressed and not deleted

-

Deselect the Select icon and rotate the model around to get a better view of the left side – the mesh of the interior corner surface half way up the left side is uneven, and you can see that the defining curves at either end comprise two curves (as created by the CAD system), so we’ll combine each of them into one to get better control of the mesh

-

Select the Combined / Composite Curves tool and reselect the Select icon Select the mid node on the left and right curves of the corner surface – the mesh is still uneven because of the mismatched element count on the top and bottom curves Select the Mesh Sizing tool which will be used to increase the mesh density of the bottom curve

-

Set Operation to Set To and enter 24 for the Number of Elements Select the Select icon and select the bottom curve of the corner surface and deselect the Select icon

-

There is one element to the right just under the corner that is colored red, Select the Zoom icon to zoom in to this element

-

To fix this element we’ll manually drag one of the corner nodes to change the element shape, select the Mesh Locate tool The Select Mesh to Edit entry is currently set to Attached to Surface, click on the down arrow to the right and select Attached to Solid Now click on the icon next to the down arrow, and select the solid (there is only one that comprises all surfaces in this model) In the Select Solid/Volume dialog click OK Select the Select icon Pick and drag the node of the red colored element that is interior to the model, moving it until the element color changes to green

-

Deselect the Select icon

The bracket model mesh is now complete and all elements pass the set quality criterion. Finally to clean up the display select the drop menu right arrow of the View Style icon in the View toolbar and deselect the Mesh Size icon

This concludes the bracket model interactive meshing demonstration.


相关文章:
Femap中文学习_图文
Femap 学习 CAE 建模过程(从大的方面说):几何模型建立,简化,网格划分,有限元...如果导入的几何模型进行了修改,那么会提醒用户), 还有一个图片的保存信息的...
Femap简介
如果将命令次数修改为 0,则 Femap 只 会根据时间来保存文件, 而不考虑命令的...划分网格和计算即可得到新的结 果;Update Material Data 复选框只 Solid ...
femap
femap_计算机软件及应用_IT/计算机_专业资料。总结FEMAP相关应用与注意事项 ...映射网格 先分线,画一个面,选映射-选要被划分的面,选控制点 4.频率分析 ...
常用CAE分析软件简介
http://www.eds.com/products/plm/femap/ MSC/PA TRAN: MSC 公司的网格划分...CAE: ABAQUS 有限元分析的前后处理模块,也是建摸、分析和仿真的人机交互 平台。...
Femap 介绍
Femap 提供了从高级梁建模、中面提取、六面体网格划分,到功能卓越的 CAD 输 入...复杂的载荷和材料 属性编辑器,方便用户修改对象属性 支持分组显示图层显示 云图...
使用CorelDRAW中的“交互式网格填充”工具填充对象
使用CorelDRAW中的“交互式网格填充”工具填充对象_IT/计算机_专业资料。使用 CorelDRAW 中的“交互式网格填充”工具填充对象使用交互网格填充工具使用“交互式网格填充...
FEMAP真正的有限元解决方案
FEMAP 产品被广泛地应用于多种工程产品系统及过程,例如:卫星、航空器、重型起重机、高真空密封器 等。FEMAP 提供了从高级梁造型、中面提取、六面体网格划分,到功能...
HyperMesh版面精华
MotionView 后处理包含了 HyperView 的功能,并结合数据绘图及 高性能的交互式 ...http://www.eds.com/products/plm/femap/ MSC/PATRAN:MSC 的网格划分软件,...
feko软件介绍
该方法可以采用波长相当甚至几个波长的尺度剖...可以导入复杂的 CAE 网格模型如: FEMAP、 Nastran、...共享内存式并行,软件支持单机多核 并行,也支持多机...
结构建模(新)
Femap/NX Nastran、 Hypermesh、 COMSOL Multiphysics、...MSC.Nastran→划分有限元网格【Element】→定义或选 ...进行后置处理【Results】和【Insight】 (Patran 读取...
更多相关标签: