MBD Simulation on IC Engine Valve Train

Aim : To simulates IC Engine Valve Train with two different Cam.(3mm & 6mm lift)

• Valve Lift.

• The contact force between

• Cam and Push Rod
• Pushrod and Rocker Arm
• Rocker Arm and Valve

The time for which the valves remained open was optimised only for single engine speed. However, as the engine speed increases, it considerably reduces the time required to fill the cylinders fully.As a result, the engine would receive less amount of charge (air-fuel mixture) which causes power-loss especially when the engine runs at high speed.To overcome this deficiency, the engineers developed VVT or ‘Variable Valve Timing’ mechanism. The VVT varies the timing of opening and closing of valves for multiple engine speeds. At high speed, the Inlet valves open quite earlier so that more air-fuel mixture or ‘charge’ enters the cylinders. This helps to increase engine’s breathing which also improves its ‘volumetric efficiency’ to a large extent.

Simuation setup

Model indivisual parts cam , pushrod , rocker-arm , valve and valve sleeve.

Position and mate parts.

Apply solid contact and material .

Then provide motor function @1500 rpm to cam and spring function to valve and valve sleeve with crtain stiffeness value.

Adjust frames to get per degree position of valve.

https://youtu.be/1H3OG7qwFz8

Valve lifts

1- 3mm

2-6mm

Valve Lift Compare

Contact Forces

#3mm lift of cam

#6mm lift of cam

Cotact force differs in x direction and magnitude force between Rocker arm and Valve.

Magnitude of Cotact force is resultant force magnitude irrespective of direction acting on valve by Rockerarm,

and force in x-direction is summation of forces in x-direction acting on valve by Rockerarm.

https://drive.google.com/file/d/1O9NQu8SJ3PTU4z7cGDhpFuw0VMzhu6ET/view?usp=sharing