The work done in a steady flow process is equal to - ∫ vdp in the Rankine cycle, the turbine work is much greater than the pump work because

Concept:

The turbine and pump are steady flow devices, for which the work done is given by -∫νdp where ν is called the specific volume of working fluid which is inverse of density i.e. and dP is the change of pressure between the outlet and inlet of the device.

Now,

• We know that for the turbine the working fluid is steam whereas for pump the working fluid is liquid water in case of the Rankine cycle.
• Since the density of steam is much lesser than that of liquid water, so the specific volume in the case of steam is much greater than that of liquid water.
• That is why the work done by the turbine is much greater than the work input required by the pump.