PROBLEMS:
- [Score: 60] Consider a steam power plant, consists of a boiler, a condenser, a pump, and a turbine (See Figure 1). Suppose that the turbine operates adiabatically with inlet steam at 6800 kPa and 550 oC and that the exhaust steam enters the condenser at 50 oC with a steam quality of 0.90 (vapor fraction). Saturated (vapor fraction = 0) liquid water leaves the condenser and is pumped to the boiler. Neglecting pump work (Ws=0) and kinetic- and potential energy changes, determine the “thermal efficiency of the cycle” and the “turbine efficiency”.
- [Score: 40] A particular power plant operates with a heat-source reservoir at 350°C and a heatsink reservoir at 30°C. It has a thermal efficiency equal to 55% of the Carnot-engine thermal efficiency for the same temperatures.
(a) What is the thermal efficiency of the plant (cycle)?
(b) To what temperature must the heat-source reservoir be raised to increase the thermal efficiency of the plant to 35%? Again η is 55% of the Carnot-engine value.
How to Collect the Assignment Answer: Each student must solve the problem individually in a A4-size PDF document file. The document file should use name of student as filename. The file should be uploaded into the following URL before 1 June 2024: https://bit.ly/3KnQW4t