Question

A steam engine based on a turbine is , The boiler tank has a volume of 100 L and initially contains saturated liquid with a very small amount of vapor at 100 kPa. Heat is now added by the burner, and the pressure regulator does not open before the boiler pressure reaches 700 kPa, which it keeps constant. The saturated vapor enters the turbine at 700 kPa and is discharged to the atmosphere as saturated vapor at 100 kPa. The burner is turned off when no more liquid is present in the as boiler. Find the total turbine work and the total heat transfer to the boiler for this process

Answer 1

C.V. Boiler tank. Heat transfer, no work and flow out. 

Continuity Eq  m₂ - m₁ = − m_e

 C.V. Turbine, steady state, inlet state is boiler tank exit state. Turbine exit state:

100 kPa => h_e = 675.5 kJ/kg

W_turb = me (h_in- h_ex) = 95.511 × (2763.5 - 2675.5)

= 8405 kJ