Module 5   :   Turning Moment Diagram for Engines and Speed Fluctuation; Power Smoothening by Flywheels.
Lecture 1 :    Turning Moment Diagram for Engines and Speed Fluctuation; Power Smoothening by Flywheels.
  Consider a typical four stroke IC Engine. The internal pressure as a function of crank angle is as shown in Fig. 5.1. In a four stroke engine, the four strokes are identified as suction, compression, power and exhaust. Power due to combustion is actually generated ONLY in one of the four strokes and hence the resulting torque on the crank shaft will also fluctuate in a similar manner. We shall now attempt to derive an expression for the gas torque.
 


Figure 5.1. Typical Pressure Vs Crank angle for a four stroke engine

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