Finite element method is a numerical method for solving problems of engineering and
mathematical physics. Typical problem areas of interest in engineering and mathematical physics
that are solvable by use of the finite element method include structural analysis, heat transfer,
fluid flow, mass transport, and electromagnetic potential.
For problems involving with complicated geometries, loadings, and material properties, it
is generally not possible to obtain analytical mathematical solutions. Hence, we need to rely on
numerical methods, such finite element method, for applicable solutions. In finite element
method, instead of solving for entire body in one operation, we formulate the equations for each
finite element and combine to obtain the solution of the whole body. FEA consists of a computer
model of a material or design that is stressed and analyzed for specific results. It is used in new
product design, and existing product refinement.
Briefly, the solution for structural problems typically refers to determining the
displacements at each at each node and the stresses within each element making up the structure
that is subjected to applied loads.
In this project, I am going to identify and discuss about the finite element method by
using ANSYS method by importing file of the object that has been draw in CATIA software.
The object’s name is Support object, to support some part in Machine part. For the material use
Objectives of the project
To familiar with the import and export file from CATIA to ANSYS
To understand how to identify the stress by using Ansys Method
To know the general steps used in the finite element method.
To know the various types of elements used in finite element method.
To summarize some advantages of the finite element method.
DISCUSSION AND ANALYSIS
In this project, the object can be used any type of CAD software that you are familiar
with, ether in SOLID work, Alibree , AutoCad, Catia and so on. The important is that, in other
to import a file from this kind of software to Ansys, you have to save it into stp file.
1. The following object has been draw by using CATIA software.
The figure 1. Draw by using CATIA software
2. Save the object in figure 1 to stp file then import to Ansys workbench. Select file,
import, chose file that you want to import, select Geometry, choose millimeter, and
Figure 2. use ansys workbench method
3. Export file from an Ansys workbench method and save it as parasolid tex.
4. Use Mechanical APDL 14.5 Import file that has been save by select import, Parasolid file,
Figure 3. after import file
5. Select Preprocessors, Add element , solid , 10node 187, apply.
6. Material Property (Aluminum E= 95E9)
7. Meshing, mash tool, choose smart size, (I am choosing 4 only ) then pick the point that you
want (Volume), apply , ok
Figure 4. after mashing volume
Next, we set up an analysis, define displacements and loadings, and solve the
Click define load , ‘Displacement’, then ‘On Area’. Pick up the location that we
want to fix. (I chose fix point at the four holes at the lower part), apply, choose ALL
DOF to be constrained, then enter 0 into the displacement value box.
9. Apply pressure in to the top of the work pieces (on area) with the value of Pressure
104.2E6, then solve
Figure 5. apply pressure value.
Figure 6. the read colure indicates the pressure that we have applied and solved
Figure 7. Deformed and unreformed solution
Figure 8. von Mises stress plot for a solid part subjected to pressure 104.2E6Pa
Material use Is Aluminum
σmax = 37.8E6Mpa
From the result above, indicates that the safety factor is not really good. We need to redesign our
part. In this new design, I delete the fillets that have applied on four edges at the top of the part.
The below figure is the news part design.
By giving the same pressure to news design the value of stress will reduce as show in figure below:
von Mises stress plot for a solid part subjected to pressure 104.2E6Pa
As a result, the safety factor will be obtained as we want.
To summary, there are many advantages of finite element method, such as it has been
applied to numerous problems, both structural and nonstructural. This method has a number of
advantages that have made it very popular. They include the ability to
1. Model irregularly shaped bodies quite easily
2. Handle general load conditions without difficulty
3. Model bodies composed of several different materials because the element equations are
4. Handle unlimited numbers and kinds of boundary conditions
5. Vary the size of the elements to make it possible to use small element where necessary
6. Alter the finite element model relatively easily and cheaply
7. Include dynamic effects
8. Handle nonlinear behavior existing with large deformations and nonlinear materials
1. First course in the finite element method Fourth Edition by Daryl L. Logan
2. First course in the finite element method Fifth Edition by Daryl L. Logan