Final answer:
The overall thermal efficiency of a steam power plant with superheat can be calculated by dividing the net work output by the heat added to the cycle. To calculate the net work output, the work done by the turbine and the work done by the pump need to be subtracted.
Step-by-step explanation:
The overall thermal efficiency of the cycle can be calculated using the formula:
Thermal Efficiency = (Net Work Out / Heat Added)
To calculate the net work out, we need to subtract the work done by the pump from the work done by the turbine. We can calculate the work done by the turbine using the formula:
Work Done by Turbine = m_dot * (h1 - h2)
Where m_dot is the mass flow rate of the steam, and h1 and h2 are the specific enthalpies of the steam at the turbine inlet and outlet respectively. Similarly, we can calculate the work done by the pump using the formula:
Work Done by Pump = m_dot * (h4 - h3)
Where h3 and h4 are the specific enthalpies of the steam at the pump inlet and outlet respectively.
Next, we can calculate the heat added to the cycle using the formula:
Heat Added = m_dot * (h1 - h6)
Where h6 is the specific enthalpy of the steam at the condenser outlet.
Finally, we can substitute these values into the thermal efficiency formula to calculate the overall thermal efficiency of the cycle.