Week 7-Long Piston With Cam

Objective: The objective is to simulate long piston and cam for frictionless, (friction=0.1) and (friction =0.2). cases and to compare the total deformation, stress and strain produced.

Materials: The material used is stainless steel for barrel, barrel cam and the cam follower.

Geometry:

For all the cases the geometry is the same. The barrel and the barrel cam are fixed and hance act as point masses.

Connections:

1. Contact Sets:

For the case 1, the contact is frictionless.

For the case 2, the contact is with friction of coefficient 0f 0.1

For the case 3, the contact is with friction of coefficient of 0.2

2. Joints:

a. Fixed: The barrel is fixed to the ground.

b. revolute: between the barrel cam and ground.

c. Translationl: Between the barrel cam and cam follower.

Mesh: The regions which come in contact with the cam follower are face sized to get better results. All the other parts are fixed and hence act as point mass.

Nodes:2901

Elements: 1082

Analysis settings:

For the first step, Initial time step is 0.1s, Min time step is 5e-002 and Max time step is 0.2s. Weak Springs is program controlled, Large deflection is turned on. All the output controls are turned to yes.

For the 2-9 Steps: Initial time step is 0.1s, Min time step is 5e-002 and Max time step is 0.3s. Weak Springs is program controlled, Large deflection is turned on. All the output controls are turned to yes.

1. Joint Rotation: A revolute joint is step up between the barrel cam and ground with the rotation of 30 degrees at each step.

Results:

Case 1: Frictionless Contact

a. Total Deformation:

b. Equivalent Strain:

c. Equivalent Stress:

Case 2: Coefficient of friction - 0.1 between the contacts.

a. Total Deformation:

b. Equivalent Strain:

c. Equivalent Stress:

Case 3: Coefficient of friction - 0.2 between the contacts.

a. Total Deformation:

b. Equivalent strain:

c. Equivalent stress:

	Total Deformatipn(mm)	Equivalent strain	Equivalent Stress(MPa)
Case 1:Frictionless Contact	35.921	0.0086	1756.6
Case 2:Frictional coefficient 0.1	35.921	0.0096	1849.1
Case 3: Frictional coefficicnt 0.2	35.921	0.012101	2339.1

Total Deformation is independent of the change in the frictional contact. Strain and stress increase as the coefficient of friction increases.