Challenge

MBD Simulation on IC Engine Valve Train

SShubhang B31 Dec 2021

AIM- To model and assemble I.C engine valve train & perform motion analysis in 2 different cases ( cam lifts)

cam lift formula-

--------------------------------------------------------------------------------------------------------------------------------------------------------------------

Geometric modelling-

cam-

push rod -

rocker arm -

valve-

valve mount-

Assembly-

--------------------------------------------------------------------------------------------------------------------------------------------------------------------

Simulation setup-

i) A motor is assigned to the axis of cam at 1500 RPM.

ii) contact forces are established between cam-pushrod, pushrod-rocker arm,rocker arm-valve.

iii) Solid body body contacts and cast carbon steel material are assigned to each part

iv) A spring of stiffness of 10N/mm and free length of 45mm is placed between valve and valve mount

v) frames pre second is set 7200.

vi) required analysis is done.

motor-

Contact forces -

Spring

--------------------------------------------------------------------------------------------------------------------------------------------------------------------

Results-

i) analysis for 3mm cam lift

contact force bewteen cam and psuh rod-

The maximum contact force is 8800 N.

contact force for push rod and rocker arm-

The maximum contact forcce is 10000N

contact force for rocker arm and valve w.r.t magnitude-

The maxmum contact force is 1700N.

contact force between rocker arm and valve w.r.t X direction-

The maximum cotact force is -480N,

There is a differnce between contact force of rocker arm-valve w.r.t magnitude and X direction because the amount of contact in X direction is very less in x direction than compared to the whole magnitude in all directions.

--------------------------------------------------------------------------------------------------------------------------------------------------------------------

For 6mm cam lift-

contact force between push rod and cam-