Tài liệu ME-430 INTRODUCTION TO COMPUTER AIDED DESIGNTORSIONAL ANALYSIS Using Pro/MECHANICA Pro/ENGINEER pptx

Step 5: To simulate the application of a torsion load on a cylindrical shaft in Pro/MECHANICA using the Total Load Applied at Point TLAP functionality, a datum point located on the appli

ME-430 INTRODUCTION TO COMPUTER AIDED DESIGN

TORSIONAL ANALYSIS Using Pro/MECHANICA

Pro/ENGINEER Wildfire 2.0

Dr Herli Surjanhata The U-Joint shown in the figure below is made of steel A torsion load of 10,000 IN-

LB is uniformly applied over the top portion surface of the U-Joint

Determine the von Mises stresses, and maximum deflection under the given torsion

load and boundary conditions

Check the convergence of your analysis

Step 1:

Using Pro/ENGINEER, create a base feature as shown in the Figure below It is done

by extruding both sides the section shown with 2 inches blind depth

Create two rounds with R = 1 inch on the left and right bottom of the base feature

Create co-axial holes of 0.75 inch in diameter on both sides of the part

Add the cylindrical portion of the part as shown below The diameter is 1.50 inches, and use extrude to the next surface option Note that the radius of the round is 0.2 inch

Make the following cut on the cylinder Round the bottom of the cut with R = 0.05

inch

Edit -> Setup -> Units

Choose Inch Pound Second (IPS) Click on Set button

Select Interpret dimensions

OK -> Close Done

Step 2:

Transfer the model to Integrated Mode of Pro/MECHANICA

From Applications pull-down menu, select Mechanica and the following window

appears Check the units to make sure it is correct

Click Continue button if the system of units is correct and consistent

From Model Type menu, select

Structure

OK

Step 3:

Define the material of U-Joint

From Properties pull-downmenu, select

Click on Failure Criterion tab

U-Joint is made of steel, and steel is ductile The most suitable failure criteria is distortion energy theory

Select Distortion Energy (von Mises) as failure criterion

Assuming the yield’s stress

of steel 60,000 psi and factor of safety 1.5, we will enter the tensile yield stress 40,000 psi

Click on OK, then Close the Materials dialog box

Step 4:

Create a surface region for applying the torque on some portion of the top part of Joint

U-Insert -> Surface Region

Or click on the toolbar located on the right

Sketch -> Done

Pick FRONT datum plane as sketching plane, and select Top then pick TOP datum plane in the graphics area

Pick the necessary additional references, and use rectangle to sketch the following section

Click on

For the surface or surfaces to

be split, Pick the top cylindrical part of the U-Joint as shown

Click on OK -> OK The surface region for applying the torque has been created

Step 5:

To simulate the application of a torsion load on a cylindrical shaft in Pro/MECHANICA using the Total Load Applied at Point (TLAP) functionality, a datum point located on the applied surface must be created This will be used for defining the load and since

we will use Total Load at Point (TLAP) and Moment, the location does not matter

Click on Datum Point Tool icon

Pick on the surface (region), and locate the point with respect to top surface and right datum plane Note again the location does not matter as long as it is located on the surface where torsion will be applied

Step 6:

Create a cylindrical coordinate system on the top of the U-Joint

Click on

Change the Type to Cylindrical Pick three datum planes – FRONT, RIGHT, and

DTM1 Click on Orientation tab to modify the orientation of coordinate system such that the Z-axis is pointing up or down

Click on OK

Step 7:

Apply the boundary conditions or constraints on the left and right holes of U-Joint

Insert -> Displacement Constraints or click on the Constraint

window appears

Enter the name of the constraint as

Cartesian coordinate system

OK, then click OK button in the

Constraint window

Note that FIXED constraint should be appeared on these surfaces

Step 8:

Apply the load on the surface region previously created - see Figure

Insert -> Force/Moment Load or click on

Enter the name of the load as

“TorsionLoad”

Click the arrow button under the Surfaces

Pick the top surface region previously created for applying the torsion load – see Figure below

Click the arrow button under the Properties

Pick the Cylindrical Coordinate System CSO

Click on button

Change the type of Distribution to

Total Load At Point

Click on the arrow button under

Distribution, and pick the datum point

Analyses and Design Studies

dialog box opens

From File pull down menu, select

New Static

Enter the name of analysis

as “U_Joint”

Select Multi-Pass Adaptive method

Maximum Polynomial Order = 9

Percent Convergence =

5

Convergence on Local Displacement, Local Strain Energy and Global RMS Stress

Click the OK button

Step 10:

Run the design study by

selecting

Click the Yes button

Click the Display study status

button to review the progress of the analysis

Make sure you have “Run Completed” message

Click Close in the Run Status dialog box

Step 8:

Review design study results

Click on to review the results of design study The Result Window Definition dialog box opens

Enter Window Name as

“von_Mises” for Von Mises stress

Enter the Title of Von

Mises Stress Distribution Plot

By default U_Joint

Design Study and

Analysis have been selected

Click on Display Options

tab

Make sure you fill in the following form (window) as shown below:

Click the OK and Show button

From Format pull down menu, select

Result Window Change the background to White

From Info pull down menu, select

View Max

Repeat the procedure and select View Min.

18Click the Copy button

Enter the name as “displ” Enter the Title of

Displacement Distribution Plot

Click the Quantity tab, and change the type to

Displacement, and the

Component to Magnitude

Check Overlay Undeformed

in the Display Options tab Click the OK and Show

button

We are also interested in convergence of the Max Von Mises Stress

Click the Copy button - in the Result Window, and name it as convm

Set the following:

Set the Display type to Graph Set the Quantity

to Measure

Click icon to select the Max Von Mises Stress

Click OK button

From Format pull down menu, select

24Notice that the max_stress_vm does converge

Plot the results for the failure index Failure index measure indicates whether a

material has failed due to the applied loads If the failure index value is equal to or more than "1" at any point in the model then the material is considered to have failed at that point

Click the Copy button - in the Result Window, and name it as Fail_index Set the following:

Set the Display type

to Fringe Set the Quantity to

Failure Index Click OK

Click icon

In the Display Result Window, make sure to highlight Fail_index ONLY, and click the OK button

The result shown above indicates that there are many areas where the Failure Index

is more that 1.0 These are the areas where material will fail Based on this

information, redesign of the U Joint can be done to bring the failure index to below 1.0 in the entire model

Save the results windows as u_joint

Click

Enter the file name

u_joint.rwd

Click OK

Click icon

In the Display Result Window, highlight

von_Mises ONLY, and click the OK button

The von Mises stress plot will be displayed

Insert -> Cutting/Capping Surfs

The Results Surface Definition dialog box appears

OK

File -> Export -> Image

Change the Output Format to JPEG Under Output Options, check To File, and enter the name for the output file (JPEG format) e.g U_joint cut

surface

Click on OK

Edit -> Delete Cutting Surf

We will be back to von_Mises stress distribution display

Insert -> Cutting/Capping Surfs

The Results Surface Definition dialog box appears