MBD Simulation on IC Engine Valve Train

OBJECTIVE : To perform a motion study of IC engine train valve.

PROBLEM STATEMENT: To run the simulation of IC engine train valve for the given conditions.

Sl.No	CAM Lift (mm)	Speed (RPM)	Material
1	3.5	1500	Cast Carbon Steel
2	6	1500	Cast Carbon Steel

 And then obtain the plots for 

• Valve Lift. 
• The contact force between 
  1. Cam and Push Rod
  2. Pushrod and Rocker Arm
  3. Rocker Arm and Valve

And explain why the contact force between the Rocker arm and valve varies while measuring with respect to the X direction and measuring with respect to magnitude. 

THEORY : A valve train is a mechanical system that controls operation of the intake and exhaust valves in an internal combustion  engine. The intake valves control the flow of air/fuel mixture (or air alone for direct-injected engines) into the combustion chamber, while the exhaust valves control the flow of spent exhaust gasses out of the combusion chamber once combustion is completed.

The IC egine train valve consist of following parts 

• Cam
• Valve
• Valve rest
• Rocker arm 
• Push rod 

SOLUTION PROCEDURE: 

Firstly we need to make the parts of the IC engine train valve in SOLIDWORKS  and then we need to assemble them all and after that we run the motion study for the given parameters.

PARTS OF IC ENGINE TRAIN VALVE.

1.CAM (3.5mm cam lift )

2.CAM (6mm cam lift)

3. VALVE REST 

4.PUSH ROD 

5.ROCKER ARM 

6.VALVE 

ASSEMBLY OF THE IC ENGINE TRAIN VALVE 

RESULTS AND PLOTS 

CASE -1

When the IC engine train valve assembly is made with the cam of 3.5mm cam lift.The following plots are generated.

1.Linear displacement of valve .

2. Contact force betwwen the cam and the push rod.

3.Contact force between the push rod and the rocker arm.

4.Contact force between the rocker arm and the value ( magnitude ).

5. Contact forces between the rocker arm and the valve ( x-component).

CASE-2

When the IC engine train valve assembly is made with the cam of 3.5mm cam lift.The following plots are generated.

 1.Linear displacement of valve .

2. Contact force betwwen the cam and the push rod.

3.Contact force between the push rod and the rocker arm.

4.Contact force between the rocker arm and the value ( magnitude ).

5. Contact forces between the rocker arm and the valve ( x-component).

Explation of contact force between rocker arm and valve.

In the plots above  contact force between the rocker arm and the valve in both the cases (3.5mm and 6mm cam lift ) we can see that while ploting the contact force between the rocker arm and valve with magnitude the values are always positive but while ploting the contact force between the rocker arm and the valve with x-component we can see that there is some negative values also this is because for a complete cycle or for one rotation of the cam the rocker arm moves forward and backward for the half half cycles but in case of magnitude there is no such condition.

GOOGLE DRIVE LINK

https://drive.google.com/drive/folders/13H827740ZHZNhh1hJ9bFwNNRZVHC8odk?usp=sharing