Chapter 6, Problem 6.90P

2. Gaseous nitrogen actuates a Carnot power cycle in which the respective volumes at the four corners of the cycle, starting at the beginning of the isothermal expansion, are V1= 10.10, V2= 14.53, V3= 226.54, V4= 157.73 liter, what is the thermal efficiency of the cycle? k=1.399 (for these problem use pressure, volume and temperature relationship).

1. A medium size power station is used to produce 30 MW net power for a refinery. The station uses steam as the operating fluid and operates according to the Carnot cycle between the pressure limits of 0.4 bar and 35 bar. Steam enters the boiler as a saturated liquid and leaves it as a dry saturated vapour. (i) List the name of the four processes in a generic Carnot cycle and state what type of energy transfer (work/heat) can be neglected in each process. (ii) Sketch a T-s diagram for the above cycle indicating the location of the four components required. (iii) Determine the dryness fraction of the steam that is fed to the condenser.

3. A medium size power station is used to produce 30 MW net power for a refinery. The station uses steam as the operating fluid and operates according to the Carnot cycle between the pressure limits of 0.4 bar and 35 bar. Steam enters the boiler as a saturated liquid and leaves it as a dry saturated vapour. (vii) Using the highest and lowest temperature values in the cycle, recalculate the efficiency of the cycle and show that it is equivalent to the result in part (vi). (viii) Calculate the thermal efficiency of the power station if the isentropic efficiency of the steam turbine is 94%. (ix) State main disadvantages of using the Carnot cycle as the basis for a power station. (x) State the name of the cycle that is used in practice in power stations, along with three key benefits over the Carnot cycle.

The figure below gives the schematic of a vapor power plant in which water steadily circulates through the four components shown. The water flows through the boiler and condenser at constant pressure and through the turbine and pump adiabatically. Kinetic and potential energy effects can be ignored. Process data follow: Process 4-1: constant pressure at 7 MPa from saturated liquid to saturated vapor Process 2-3: constant pressure at 14 kPa from x2 = 69.6% to x3 = 32.7% Pump lin Boiler Condenser Qout 1 Turbine W₁

A modified Rankine steam cycle is shown for reheating, a closed feedwater heater, and an open feedwater heater. high pressure turbine receives 100 kg/s of steam from the steam boiler. The feedwater heater output states for boiler feedwater and condensed steam are the ideal states normally assumed. The following data tables give saturation data for pressures and data for h and s at selected states. (a) Draw the T-s diagram for the ideal cycle. (b) Determine the net power output of the cycle, in MW.

A 136 kg/s steam with an inlet condition of 52 bar, 400 C enters a rankine turbine and expands to 36 kPa. determine the work, the thermal efficiency, and the steam rate (a) for the cycle, (b) for the turbine. (c) With the same specifications, consider the steam expanded on an actual turbine and the brake steam rate is 4800 g/kwh and the driven electric generator has an efficiency of 0.93. Find Brake Thermal Eff, Brake Engine Eff, Combined Work, and quality or temperature of actual exhaust steam

Rankine Cycle (Thermodynamics) Show the illustration diagram and complete and step by step solution.

shown below is P-V diagram for a reversible cycle enclosed by 4 reversible process curves.  The curve 1-2 and the curve 3-4 are  reversible isothermal processes, and the curve 2-3 and the curve 1-4 are reversible adiabatic processes. If the cycle direction is counter clockwise, answer the question below. What is the cycle?____             A. Carnot cycle   B. ideal heat engine cycle   C. Carnot refrigeration cycle   D. Reversed refrigeration cycle

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