Indicator Diagram of a Simple Steam Engine

Indicator Diagram of a Simple Steam Engine Points : Indicator Diagram of a Simple Steam Engine It is a graphical representation of the variation in pressure and volume of steam inside the cylinder or p.v diagram. As a matter of fact, the theoretical indicator diagram of a simple steam engine has been developed from that of a modified Rankine cycle. It is based on the following assumptions.
1. The opening and closing of steam ports is instantaneous.
2. There is no pressure drop due to condensation.
3. There is no wire drawing due to restricted valve opening.
4. The steam is admitted at boiler pressure and exhausted at condenser pressure.
5. The expansion (or compression) of the steam is hyperbolic (i.e. pv = c).

A little consideration will show, that the above assumption are not correct from the practical point of view. As a result of this, it has lead to the change in the indicator diagram from the basic modified Rankine cycle.