Week 7-Long Piston With Cam

Transient Simulation of a long Piston cam Mechanism Model Using ansys Workbench.

Objective: Transient simulations on a piston and cam mechanism model with three different cases

Case1- Frictionless contact,

Case2- Friction co-efficient 0.1

Case3-Friction coefficient 0.2

Procedure: create Transient structural analysis and in engineering data select the material structural steel.

Material:

The material used for the entire simulations was structural steel

Input Geometry

The given module was inserted into the mechanical GUI. Check in space claim for any defeat in model

Then open Ansys mechanical and rename the geometry as Barrel, Barrel CAM and CAM Follower then assign the Structural steel material make stiffness Behaviour as Rigid

Contacts:

Two contacts created in the whole setup with frictionless or frictional type with friction coefficient of 0.1 and 0.2 and interface treatment is set to add offset, Ramped effect

Case1-Frictionless contact

Case2-Fricitional with 0.1 as the frictional contact

Case3-Fricitonal with 0.2 as the frictional contact

Joints:

Three joints created in whole geometry

Fixed-Ground to Barrel, Revolute- Ground to Barrel CAM, Translational- Barrel to Cam_ Follower

Mesh- Face Sizing option use for meshing 3mm element size

Analysis setting- the simulations run for 9steps. so, the number of steps is set as 9.In the first step large deflection set to on and defined by time. initial time step to 0.1s, Minimum time step set to 5e-2s and Maximum time set to 0.2s and stabilization set to constant , method to energy and energy dissipation ratio to 0.1,activations for first steps to yes. In output contact set all output to yes

The second steps to nine step large deflection set to on define by time. Carry over time set to on, initial time steps set to 0.1s, Minimum time steps set to 5e-2s and Maximum time step set 0.3s and stabilization set to constant , method to energy dissipation ratio to 0.1, activation for first steps to yes. In output contact set all output to yes except contact miscellaneous

Boundary conditions

Joint –rotation –cam is provided a rotation of 270 degrees

Solutions:

All the necessary output variable are selected such as von Mesis stress, stress intensity, equivalent strain etc.

Result –

Case1-Frictionless contact

Directional Deformation a axis

Equivalent stress

Equivalent elastic strain

Equivalent stress on cam follower

Case2-Fricitional with 0.1 as the frictional contact

Directional Deformation x axis

Equivalent stress

Equivalent elastic strain Max

Equivalent stress on cam follower

Case3-Fricitonal with 0.2 as the frictional contact

Directional Deformation a axis

Equivalent stress

Equivalent elastic strain Max

Equivalent stress on cam follower

	Directional Deformation on A Axis	Equvialent stress on Cam follower	Equivalent strain
Case1- Frictionless contact,	11.2 mm	1511.2 Mpa	8.5611e-003 mm/mm
Case2- Friction co-efficient 0.1	11.2 mm	1538.3 Mpa	9.0062e-003 mm/mm
Case3-Friction coefficient 0.2	11.249 mm	1856.6 Mpa	9.6604e-003 mm/mm

Inference –

Equivalent stress- Stress keeps on increasing as we increase the friction coefficient value .As the frictional coefficient value increase it resists more the movement of the follower and the follower and thus the Stress develops at the stem of the follower

Directional Deformation- it is increasing slight with increasing friction coefficient value.

Equivalent Elastic strain- Also because of the same reason as equivalent stress, Equivalent strain also increases due to more resistance offered.