Question

A steam power plant operates on an ideal regenerative Rankine cycle with two open feed water heaters Steam enters the turbine at 10 MPa and 600°C and exhausts to the condenser at 20 kPa Steam is extracted from the turbine at 0.8 MPa and 0.4 MPa. Water leaves both feed water heaters as saturated liquid. The mass flow rate of the steam through the boiler is 16 kg/s. Show the cycle on T-S diagram

Answer 1

The maximum theoretical efficiency for a heat engine operating between the temperatures of 300°C and 27°C is calculated using the Carnot efficiency formula and comes out to be 47.63% after converting the temperatures to Kelvins.

Step-by-step explanation:

To calculate the maximum theoretical efficiency of a heat engine operating between two temperatures, we use the Carnot efficiency formula:

EffC = 1 - (Tc / Th)

First, we need to convert the given temperatures from Celsius to Kelvins:

• The high temperature (Th): 300°C + 273.15 = 573.15 K
• The cold temperature (Tc): 27°C + 273.15 = 300.15 K

Now, we can plug these values into the Carnot efficiency formula:

EffC = 1 - (300.15 K / 573.15 K)

EffC = 1 - 0.5237

EffC = 0.4763 or 47.63%

Therefore, the maximum theoretical efficiency for a heat engine operating between 300°C and 27°C is 47.63%.