catia fem.pdf - CATIA V5 FEA Tutorials Releases 12 13 Nader...

CATIA V5
FEA Tutorials
Releases 12 & 13
Nader G. Zamani
University of Windsor
SDC
Schroff Development Corporation
PUBLICATIONS

CATIA V5 FEA Tutorials 2-1
Chapter 2
Analysis of a Bent Rod with
Solid Elements

2-2 CATIA V5 FEA Tutorials
Clamped end
loaded end
Introduction
In this tutorial, a solid FEA model of a bent rod experiencing a combined load is created.
No planes of symmetry exist and therefore simplifications cannot be made. Finally, the
significance of the von Mises stress in design equation is discussed.
1 Problem Statement
The bent rod, shown to the right, is clamped at one end and
subjected to a load of 2000 lb as displayed. The steel rod has a
Young modulus of 30E+6 psi and Poisson ratio 0.3 .
The nominal dimensions of the rod are also displayed below.
Although this problem is more efficiently handled with beam
elements, we propose to use solid elements.
There are two types of solid elements available in CATIA V5:
linear and parabolic. Both are referred to as tetrahedron
elements and shown below.
The linear tetrahedron elements are faster computationally but less accurate. On the other
hand, the parabolic elements require more computational resources but lead to more
accurate results. Another important feature of parabolic elements is that they can fit
curved surfaces better. In general, the analysis of bulky objects requires the use of solid
elements.
2 Creation of the Part in Mechanical Design Solutions
Enter the Part Design workbench which can be
achieved by different means depending on your CATIA
customization. For example, from the standard windows
toolbar, select File > New
.
From the box shown on
the right, select Part . This moves you to the part design
workbench and creates a part with the default name
Part.1 .
5 in
8 in
1 in
Cross sectional
Radius is 1 in
Tetrahedron Elements
linear parabolic

Analysis of a Bent Rod with Solid Elements 2-3
In order to change the default name, move the curser to Part.1 in the tree, right click and
select Properties from the menu list.
From the Properties box, select the Product tab
and in Part Number type wrench . This will be
the new part name throughout the chapter. The tree
on the top left corner of the screen should look as
displayed below.
From the tree, select the XY plane and enter the Sketcher
.
In the Sketcher, draw a
circle , and dimension it . In order to change the dimension, double click on the
dimension on the screen and in the resulting box enter radius 1.
Your simple sketch and the Constraint Definition box used to
enter the correct radius are shown below.
Leave the Sketcher
.
From the tree, select the XY plane and enter the Sketcher
.
Draw the spine of the bent
rod by using Profile and dimension it to meet the geometric specs. In the Sketcher,
the spine should match the figure below on the right. Upon
leaving the Sketcher , the screen and the tree should be as
shown below.

2-4 CATIA V5 FEA Tutorials
You will now use the ribbing operation to extrude the
circle along the spine (path). Upon selecting the rib
icon , the