Question

A steam turbine operates adiabatically at a power of 4000KW. Steam enters the turbine at 2500kPa and 500 degree celcius and exhausts from the turbine as saturated vapour at 20kPa.

a. What is the steam rate through the turbine?
b. What is the turbine efficiency?

Answer 1

To find the steam rate through the turbine, use the first law of thermodynamics. To calculate turbine efficiency, find the heat input and power output.

Step-by-step explanation:

To determine the steam rate through the turbine, we can use the first law of thermodynamics, which states that the power output of the turbine is equal to the mass flow rate of the steam multiplied by the specific enthalpy change. The specific enthalpy change can be calculated using the specific heat capacity of water vapor at constant pressure. The steam rate can be found by rearranging the equation: mass flow rate = Power output / specific enthalpy change.

To calculate the turbine efficiency, we need to know the heat input and the power output. The heat input can be calculated using the specific enthalpy of the steam entering the turbine and the mass flow rate. The turbine efficiency can then be found by dividing the power output by the heat input and multiplying by 100%.