Chapter 9, Problem 9.46P

Steam enters the turbine at 10 MN/m2and 450oC. The steam expanded in the turbine down to the condenser pressure of 20 kN/m2. The condensate leaving the condenser is pumped to the boiler pressure directly. The turbine has an isentropic efficiency of 89%, and the mass of steam generated in the boiler is 5 kg/s. Find: Cycle thermal efficiency. Plant power output.Neglect the pump work and draw the cycle on a T – s diagram. Hint: 1 MN/m2= 10 bar

Open feed water heater in the power plant operating according to the Rankine cycle with ideal intermediate steam is used. Turbine inlet state is 10MPa 650C. Condenser pressure is 10 kPa. Intermediate steam taking takes place at a pressure of 2 MPa. The intermediate steam mass flow rate depends on the total mass flow. Find the ratio. Find the thermal efficiency. TIP: Treat the mass flow entering the turbine by saying 1, and r for the intermediate steam. Result: r = 0.239, yield 45.2%

Indicate TS- Diagram and Use SI unit Steam Table In a steam power plant that uses reheat cycle steam at 15.5 MPa, 545 °C enters the engine and expands to 1.95 MPa. At this point the steam is withdrawn and passes through a reheater. It reenters the engine at 535 °C. Expansions now occur to the condenser pressure of 0.0035 MPa. Find the efficiency in %.

In an ideal regenerative cycle, steam enters the turbine at 6 Mpa. 500 °C. Steam is extracted at 0.2 Mpa and 0.275 Mpa. Then leaves the condenser at 0.1 Mpa. Find the efficiency in % IF the mass recirculating inside the cycle is 3.63 kg/s.

A 60,000 kw turbine in a reheat cycle steam at 15 MPa, 540˚C enters the engine and expands to 1.95 MPa and 260°C. It reenters the engine at 1.8 MPa and 540˚C. Expansion now occurs to the condenser pressure of 0.0035 MPa. The steam flow is 147,000 kg/hr, generator efficiency is 96%. For actual engine find combined thermal efficiency, combined steam rate, and combined engine efficiency.

Н.W A smaller power plant produces steam at 3 MPa, 600•C, in the boiler. It keeps the condenser at 45 C by the transfer of 10MW out as heat transfer. The first turbine section expands to 500 kPa, and then flow is reheated followed by the expansion in the low-pressure turbine. Find the reheat temperature so that the turbine output is saturated vapor. For this reheat, find the total turbine power output and the boiler heat transfer. [Answer. (Reheat temperature= 529°C , total turbine power output= 6487 kW, the boiler heat transfer= 16 475 kW)]

A power plant operating in a Reheat Rankine Cycle produces steam at 3 MPa, 600oC in the boiler. It keeps the condenser at 45oC by transfer of 10 MW out as heat transfer. The first turbine section (high-pressure) expands to 500 kPa and then flow is reheated followed by the expansion in the low-pressure turbine. Provide a detailed solution. Avoid shortcuts. Solve for the High-Pressure and Low-Pressure Turbines work output (kJ/kg)

A power plant operating in a Reheat Rankine Cycle produces steam at 3 MPa, 600oC in the boiler. It keeps the condenser at 45oC by transfer of 10 MW out as heat transfer. The first turbine section (high-pressure) expands to 500 kPa and then flow is reheated followed by the expansion in the low-pressure turbine. Provide a detailed solution. Avoid shortcuts. Compute for the Pump work input (kJ/kg)

A reheat steam cycle has 13500 kPa throttle pressure at the turbine inlet and 2800 kPa reheat pressure. The throttle and reheat temperature of the steam is 540°C. The condenser pressure is 3.4 kPa. Find the cycle thermal efficiency in %. Note: At 13.5 MPa, tsat 333.88 deg C, sf = 3.5921 kJ/kg-K, Sg = 5.4022 kJ/kg-K. If the steam table is needed, please use the green book entitled "Thermodynamics Properties of Water Including Vapor, Liquid, and Solid Phases" by Keenan, Keyes, Hill, and Moore.