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Introduction to ANSYSMechanical

Customer Training Material

Workshop 6.2

Pre-Stressed Vibration Analysis

Introduction to ANSYS Mechanical

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Customer Training MaterialGoals• Our goal is to simulate the modal response of the tension link (shown

below) in both a stressed and unstressed state. • Specifically, we will load the link with a 4000 N tensile load and

compare the natural frequency to that of the unloaded component.

Introduction to ANSYS Mechanical

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Customer Training MaterialProject Schematic1. Double click Static Structural in

the Toolbox to create a new system.

2. Drag/drop a “Modal” system onto the “Solution” cell of the static structural system.

2.

1.

Introduction to ANSYS Mechanical

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Customer Training Material

• When the schematic is correctly set up it should appear as shown here.

• The “drop target” from the previous page indicates the outcome of the drag and drop operation. Cells A2 thru A4 from system (A) are shared by system (B). Similarly the solution cell A6 is transferred to the system B setup. In fact, the structural solution drives the buckling analysis.

. . . Project Schematic

“Drop Target”

Introduction to ANSYS Mechanical

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Customer Training Material. . . Project Schematic• Verify:– Project units are set to “Metric (kg, mm, s, C, mA, mV).– “Display Values in Project Units” is checked (on).

Introduction to ANSYS Mechanical

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Customer Training Material. . . Project Schematic3. From the static structural system

(A), RMB the Geometry cell and “Import Geometry”. Browse to the file “Tension_link.stp”.

4. Double click the “Model” cell to open the Mechanical application.

3.

Introduction to ANSYS Mechanical

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Customer Training MaterialSetup5. Set the working Unit System:– Units > Metric (mm, kg, N, s, mV, mA)

6. Apply supports to the model (highlight “Static Structural” (A5): a. Highlight one of the inside faces of one washer

“RMB > Insert > Fixed Support”.b. Highlight the face on the rim of the other

washer “RMB > Insert > Frictionless Support”.

5.

b.

Fixed Support

Frictionless Supporta.

Introduction to ANSYS Mechanical

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Customer Training MaterialPreprocessing7. Apply tensile load to the model:

a. Orient the model as necessary and zoom in on the inside face of the washer where the frictionless support is applied to the rim.

b. “RMB > Insert > Force”.c. In the “Details of Force”, change to

“Components”d. Enter “4000” in the “Z” component

Magnitude field.• Note: depending on your choices for

supports the load may need to be defined as – 4000 N to put the rod in tension

c.

d.

a.

Force

Introduction to ANSYS Mechanical

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Customer Training MaterialAnalysis Settings8. Highlight the modal “Solution” branch (B6)

and Solve.

– When solution completes

9. Insert modal results:a. RMB in the timeline and “Select All”.b. RMB in the timeline and “Create Mode Shape

Results”.

10. RMB the Solution branch and “Evaluate All Results”.

Introduction to ANSYS Mechanical

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Customer Training MaterialPostprocessing11. Highlight various results to view displaced mode shapes.

Introduction to ANSYS Mechanical

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Customer Training Material… Postprocessing• This table illustrates the change in the first natural frequency as the

force is increased (note this table is for illustration only and is not part of the workshop).