Chapter 8, Problem 8.8P

Superheated steam at a pressure of 300 bar and a temperature of 550 ℃ enters a turbine made up of two stages. Steam exits the first stage of the turbine at 35 bar and gets reheated at a constant pressure at 550 ℃. Each stage of the turbine has an isentropic efficiency of 80%. The isentropic efficiency of the pump is 85%. The pressure of the condenser is 10 kPa. (a) Sketch the cycle in a T-s diagram and calculate the enthalpy at each point of the cycle. (b) Calculate the flow rate of the working fluid if the power output of the turbine is 100 MW. (c) Calculate the thermal efficiency of the cycle. (d) Double check the result for the heat rejected in the condenser.

Steam enters the turbine of a steam power plant, operating on Rankine cycle, at 10 bar, 300oC. The condenser pressure is 0.1 bar. The steam leaving the turbine is 90% dry. Calculate the adiabatic efficiency of the turbine and the cycle efficiency. Also, draw a suitable h-s diagram. Neglecting pump work

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

Steam enters the turbine of a Rankine cycle at 16 MPa, 560°C. The condenser pressure is 8 kPa. The turbine and pump each have isentropic efficiencies of 85%, and the mass flow rate of steam entering the turbine is 120 kg/s. Determine the net power developed, in kW. the rate of heat transfer to the steam passing through the boiler, in kW. the thermal efficiency.

A 155-MW two stage ideal reheat cycle steam power plant has the steam generator and condenser operating between the pressure limits of 89 bar and 75mm Hgabs, respectively. Steam exits the HP- turbine at 11 bar, 205 °C, exits the IP-turbine at 1.0 bar, 130°C, and exits the LP-turbine with a 7.5% moisture content. For the ideal cycle, determine: a. The temperature of steam entering the HP-turbine, IP- turbine and LP-turbine b. The percentage of the total heat supplied constituted by the first reheater c. The percentage of the total heat supplied constituted by the second reheater d. The rate of heat addition (kW) e. The rate of heat rejection (Kw f. The turbine and cycle thermal efficiencies g. The cycle and turbine steam rate (high pressure; intermediate pressure; Low pressure)

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Problem 1 In a Rankine Thermodynamic cycle, steam leaves the boiler and enters the turbine at 600 psia, 800 °F. The condenser pressure is 1 psia. After presenting a schematic of the problem in addition to clearly labeled and explained T-s and h-s diagrams, you are asked to determine the following: (a) Pump work required per Ibm of working fluid. Quality of fluid at turbine inlet. Work output of turbine per lbm of working fluid. Energy input to the boiler per lbm of working fluid. Heat rejection by the condenser per Ibm of working fluid. Determine the cycle thermal efficiency. (d) (e) (f)

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A binary vapour cycle operates on mercury and steam. Standard mercury vapour at 4.5 bar is supplied to the mercury turbine, from which it exhausts at 0.04 bar. The mercury condenser generates saturated steam at 15 bar which is expanded in a steam turbine to0.04 bar.(i) Determine the overall efficiency of the cycle.(ii) If 48000 kg/h of steam flows through the steam turbine, what is the flow through themercury turbine ?(iii) Assuming that all processes are reversible, what is the useful work done in the binaryvapour cycle for the specified steam flow ?(iv) If the steam leaving the mercury