30.2 KINEMATICS AND DYNAMICS

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Basically the engine has rotating parts that generally behave as multiple crank slider mechanisms. The force is applied on the slider, and the crank is rotated as a result.

This analysis begins with a model of the mechanism. We can use this to do a static and kinematic analysis of the mechanism. We can find the driving force on the piston as a pressure of the gas es it expands, and the area of the piston.

Next, to do the dynamic analysis of the engine we need dynamic parameters for each of the components. In practice we would also need to consider the bearings, pins, etc.

The results of this analysis will be a time variant function for each cylinder. These can then be combined for all of the cylinders in the engine to get an overall dynamic function for the engine. The total mass of the engine will tend to act as an inertial dampener for the reciprocating forces in the engine.