Week 1 Spur Gear Challenge
Objective:To perform the static structural analysis on a spur gear and find out the total deformation, Equivalent stress, Stress intensity and Location of fracture for the three materials given a nd compare them.Also conclude which material is the best one based on results.
Procedure:
1.Open the ansys workbench.Select the Static structural analysis system. Import the provided geometry into the software by right clicking on geometry and going for import geometry.
2.Go to Engineering Data and locate the Ansys GRANTA material section under Engineering Data sources. Select cast iron,EN GJL 100 material inside the list of the materials.Locate for cast steel and cast bronze. They are absent, so create them by giving the properties as shown below.
3.Open ansys mechanical.Select Geometry and rename the two gears as Left and right gears respectively.
4.Initially, Select Cast iron as a material assingment for the two gears.
5.Move to contacts.Select the faces of the contact and target gears that is to be in contact while gear rotates.Here there are 26 of both gears.So select wisely.
6.Change the contact type to frictional.Formulation as Augmented Lagrange and interface treatement as Adjust to touch.
7. Right click on contacts and insert joints.Select 2 faces of contact gear(as shown below) for the scope.Ensure body to ground contact.Also provide the revolute pair between them.Do same for the target gear.
8.Go to Analysis settings.Choose 6 number of steps and select the the steps visible on the right side of sceen as shown and change all the other details as shown in below pics.
9. Mesh the gears with element size of 2mm as an optimized size.Then check for number of nodes/elements generated under statistics.It should be below the maximum limit of the version used.Move on if it is correct.
9.Select joint load from static structural tools.Provide the joint created for left gear in scope.Select type as rotation.Give magnitude of the angles in form of a tabular data.
10.For the right gear, select type as moment and insert the moment values in tabular data taking care of direction of rotation. Make sure to change units.
11.Solve the mathematical modal and obtain the results for total deformation, Equivalent stress, stress intensity.
12.Solve the solution again by changing the material to cast steel and then with cast bronze.
COMPARISON BETWEEN THE 3 CASES
Case-1 Case-2 Case-3
Total Deformations- 
Maximum deformation(mm)- 30 30 30
Equivalent stress- 
Maximum Equivalent stress(MPa)- 288.29 288.19 288.35
Stress intensity- 
Maximum Stress intensity(MPa)- 303.66 305.8 308.19
Location of fracture- 
Material Recommended: Cast iron(ductile)
Reason: The maximum stress intensity of cast iron is least among the 3 materials.There is very little difference between the equivalent stresses of the 3 cases.Hence on the basis of stress intensity, we choose Cast iron i.e case-1.
The animations for results are attached below