Week 7-Long Piston With Cam
Ansys Week 7 - Long piston with cam
AIM
To perform a transient analysis on the piston and cam mechanism model.
OBJECTIVE
To run the analysis on the piston and cam mechanism with frictionless contact, frictional contact with 0.1 and 0.2 for a total number of 3 cases. This needs to be followed with transient analysis for the piston and cam mechanism model.
MATERIAL PROPERTY
Structural Steel
Fig 1: Structural Steel Properties
PROCEDURE
Importing the geometry in the space claim module of the long piston with cam to the geometry and its surface, also to check whether the geometry damages.
Fig 2: Piston cam geometry
And then opening the model in the mechanical module, renaming the each part such barrel, bareel_CAM, and CAM_follower. The barrel and breel_CAM will be the rigid body in stiffness behaviour.
Fig 3: Renaming each part
Connections
The contacts are changed by (flip/contact target) and then for case 1 giving the contact type as fictionaless, for others Cases Frictional value 0.1 to 0.2. The faces of the contacts body is selected only 2 faces of cam_follower.
Fig 4: Connections
Joints
The barrel of the body would be fixed so the fiexd body to ground joint is given by selecting the face of the barrel.
Fig 5: Fixed Joint
The barrel cam will be rotating and following the follower path, so for rotation motion the revolute barrel to cam joint is provided with selecting 1 face of the barrel_cam.
Fig 6: Revolute joint
The follower is attached to the barrel is translate the motion to the follower so the transitional join is given with selecting the body to body by selecting the inner barrel with outer barrel roating in same x axis.
Fig 7: Transitional Joint
Mesh
The face sizing is given for the barrel_cam and follower by selecting with 7 faces of the geometry and then elements size is 3mm.
Fig 8: Face sizing
Fig 9: Mesh
Analsyis settings
The setup for this simulation is given for 9 steps for step 1 the settings is different with the auto time step ON, with initial time step 0.1s, minimum time step (5e-2s), and maximum time step of (0.2s). The large deflection is ON, with stabilization is Constant, Energy dissipation ratio 0.1, and Activation for first substep is ON (YES) and output control are on except contact / general miscellaneous is OFF (NO).
For step 2 to 9 the initial time step 0.1s, minimum time step (5e-2s), and maximum time step of (0.3s).
Fig 10: Analysis settings
A joint rotation is given for the barrel to revolue at partciluar angle for each following with 30 degree to 270 degree.
Fig 11: Joint rotation
RESULTS
Case 1: Frictionaless
Equivalent von mises stress
Fig 12: Equivalent von mises stress
Equivalent elastic strain
Fig 13: Equivalent elastic strain
Total Deformation
Fig 14: Total Deformation
Case 2: With friction of 0.2
Equivalent von mises stress
Fig 15: Equivalent von mises stress
Equivalent elastic strain
Fig 16: Equivalent elastic strain
Total Deformation
Fig 17: Total deformation
Case 3: With Friction of 0.3
Equivalent von mises stress
Fig 18: Equivalent von mises stress
Equivalent elastic strain
Fig 19: Equivalent elastic strain
Total Defromation
Fig 20: Total deformation
CONCLUSION
| Sr. No | Equivalent von mises stress (Avg) MPa | Equivalent elastic strain (Avg) mm/mm | Total deformation (Avg) mm |
| Case 1 | 111.1 | 6.7049e-004 | 18.289 |
| Case 2 | 117.83 | 7.0968e-004 | 18.304 |
| Case 3 | 138.29 | 8.2995e-004 | 18.336 |
The results are obtained for the firctionaless contact, and the friction coefficient value from 0.2 to 0.3, For the case 1 values dor stress and strain is 111.12 Mpa and 6.70 e-004 mm/mm, also for total deformation 18.289 comparing this value to the friction coefficient it increases with value from 0.2 to 0.3. The value for the case 3 for equivalent von mises stress, elastic strain and total deformation is 138.29 MPa, 8.2995e-004 mm/mm, and 18.336 mm.