MBD Simulation on IC Engine Valve Train

AIM:

To design and perform motion analysis of an IC Engine valve of different cam-lifts using solid works MBD.

OBJECTIVES:

1. To get familiar with IC engine valve mechanism

2. Plotting different graphs like linear displacement of the valve, contact forces between the solid bodies and studying them for better understanding.

PROCEDURE:

1. Make different 3d bodies with proper dimensions and save them with appropriate names.

2. Study and input the formulae of cam lift and make the required changes in the cam body.

3. Now assemble the parts with proper constraints and make physical dynamics study for proper contact.

4. Make sure that solid works add on is kept on and enter into the motion study by changing animation to motion analysis

5. Give proper contact between solid bodies along with material, attach the motor to the cam of 1200rpm and make precise contact with around 7200 frames per second

6. Install the spring with the proper value of spring stiffness and tension within the spring.

7. Now calculate and plot different graphs based on the requirement.

RESULTS AND DISCUSSION:

1.linear displacement of the valve remains uniform with both cam lifts but little increase in the magnitude of the valve so, higher cam lift makes opens the valve further so more air/fuel mixture or exhaust can flow past the valve.

2. The contact force of 6mm cam lift is more than the 3mm cam lift so from here we can conclude that geometry of cam effects amount of opening of the valve.

3. The contact force between the rocker arm and valve in a certain direction that is in X-direction provides negative value due to frictional contact while plotting magnitude it provides positive since it doesn't bother about direction.

CAM LIFT:

Cam lift=(L-R1)+R2

where,

L=Distance between 2 circle centres

R1=Radius of lower circle

R2=Radius of upper circle