The net power output of an ideal reheat-regenerative cycle is (80 MW). Steam enters the HP turbine at (80 bar) and (500 C°), and expands till it becomes saturated vapor. Some of the steam then goes to an open feed water heater and the balance is reheated to (400 C°), after which it expands in the LP turbine to (0.07 bar). Determine (a) The reheat pressure, (b) The steam mass flow rate to the HP turbine, and (c) The thermal efficiency.

The net power output of an ideal reheat-regenerative cycle is (80 MW). Steam enters the HP turbine at (80 bar) and (500 C°), and expands till it becomes saturated vapor. Some of the steam then goes to an open feed water heater and the balance is reheated to (400 C°), after which it expands in the LP turbine to (0.07 bar). Determine (a) The reheat pressure, (b) The steam mass flow rate to the HP turbine, and (c) The thermal efficiency.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

See similar textbooks

Similar questions

Consider a regenerative power cycle with an open feedwater heater. water vapor enters the turbine at 8.0 MPa, 480°C and expands to 0.7 MPa where part of this vapor is extracted and presented to the open feedwater heater operating at 0.7 MPa. The rest of the steam expands in the second stage of the turbine to the condenser pressure of 0.008 MPa. The condenser outlet is saturated liquid at 0.7 MPa. The isentropic efficiency of each turbine stage is 85% and each pump operates isentropically. If the net power of the cycle is 100 MW, determine:1.Thermal performance and2. The mass flow of steam entering the first stage of the turbine, in kg/h.
A binary vapor power cycle consists of two ideal Rankine cycles with steam and Refrigerant 134a as the working fluids. The mass flow rate of steam is 2 kg/s. In the steam cycle, superheated vapor enters the turbine at 8 MPa, 600C, and saturated liquid exits the condenser at 250 kPa. In the interconnecting heat exchanger, energy rejected by heat transfer from the steam cycle is provided to the Refrigerant 134a cycle. The heat exchanger experiences no stray heat transfer with its surroundings. Superheated Refrigerant 134a leaves the heat exchanger at 600 kPa, 30C, which enters the Refrigerant 134a turbine. Saturated liquid leaves the Refrigerant 134a condenser at 100 kPa. Determine (a) The net power developed by the binary cycle, in kW. (b) The rate of heat addition to the binary cycle, in kW. (c) The thermal efficiency of the binary cycle.
A binary vapor power cycle consists of two ideal Rankine cycles with steam and Refrigerant 134a as the working fluids. The mass flow rate of steam is 2 kg/s. In the steam cycle, superheated vapor enters the turbine at 8 MPa, 560°C, and saturated liquid exits the condenser at 50 kPa. In the interconnecting heat exchanger, energy rejected by heat transfer from the steam cycle is provided to the Refrigerant 134a cycle. The heat exchanger experiences no stray heat transfer with its surroundings. Superheated Refrigerant 134a leaves the heat exchanger at 600 kPa, 30°C, which enters the Refrigerant 134a turbine. Saturated liquid leaves the Refrigerant 134a condenser at 100 kPa.Determine:(a) the net power developed by the binary cycle, in kW.(b) the rate of heat addition to the binary cycle, in kW.(c) the percent thermal efficiency of the binary cycle.(d) the rate of entropy production in the interconnecting heat exchanger, in kW/K.
In an ideal Reheat cycle , the steam throttled condition is 7 Mpa and 460 C. The steam is then reheated to 1.5 MpA and 460 C . If turbine exhaust is 50 C ,determine the following: A.) Quality after turbine expansion B.) Turbine work C.) Heat added in the boiler D.) Heat rejected from the condenser E.) Pump work F.) Net work G.) Cycle efficiency
1.10Water is the working fluid in a reheat-regenerative Rankine cycle with one closed feedwater heater and one open feedwater heater. Steam enters the turbine at 1400 lbf/in.2 and 1000°F and expands to 500 lbf/in.2, where some of the steam is extracted and diverted to the closed feedwater heater. Condensate exiting the closed feedwater heater as saturated liquid at 500 lbf/in.2 undergoes a throttling process to 120 lbf/in.2 as it passes through a trap into the open feedwater heater.The feedwater leaves the closed feedwater heater at 1400 lbf/in.2 and a temperature equal to the saturation temperature at 500 lbf/in.2 The remaining steam is reheated to 900°F before entering the second-stage turbine, where it expands to 120 lbf/in.2 Some of the steam is extracted and diverted to the open feedwater heater operating at 120 lbf/in.2 Saturated liquid exits the open feedwater heater at 120 lbf/in.2The remaining steam expands through the third-stage turbine to the condenser pressure of 3.5…
Problem 8.030 SI A power plant operates on a regenerative vapor power cycle with one open feedwater heater. Steam enters the first turbine stage at 12 MPa, 560°C and expands to 1 MPa, where some of the steam is extracted and diverted to the open feedwater heater operating at 1 MPa. The remaining steam expands through the second turbine stage to the condenser pressure of 50 kPa. Saturated liquid exits the open feedwater heater at 1 MPa. The net power output for the cycle is 330 MW. Assume that both turbine stages and both pumps have an isentropic efficiency of 75%.Determine:(a) the percent cycle thermal efficiency. (Ans is 30.5%)(b) the mass flow rate into the first turbine stage, in kg/s. (Ans is 306.9 kg/s)(c) the rate of entropy production in the open feedwater heater, in kW/K.
A power plant operates on a regenerative vapor power cycle with one open feedwater heater. Steam enters the first turbine stage at 12 MPa, 560°C and expands to 1 MPa, where some of the steam is extracted and diverted to the open feedwater heater operating at 1 MPa. The remaining steam expands through the second turbine stage to the condenser pressure of 17 kPa. Saturated liquid exits the open feedwater heater at 1 MPa. The net power output for the cycle is 215 MW.For isentropic processes in the turbines and pumps, determine:(a) the percent cycle thermal efficiency.(b) the mass flow rate into the first turbine stage, in kg/s.(c) the rate of entropy production in the open feedwater heater, in kW/K.
A simple rankine ideal cycle with water as the working fluid. Twenty kilograms of steam enters the turbine at 7.356 MPa and 500.356 oC and is cooled in the condenser at a pressure of 10.356 KPa by running cooling water from a lake through the tubes of the condenser at rate of 2000 kg. Show the T-s diagram and schematic of simple rankine cycle. For cycle determin (a) the turbine work, (b) the heat added, (c) the temperature rise of the cooling water, (d) the thermal efficiency of the cycle. For engine, determine (e) the heat added, (f) the thermal efficiency of the engine, and (g) Draw the T-s and schematic diagram.
Consider a regenerative vapor power cycle with a single open feedwater heater. Steam enters the first turbine stage at 12MPa, 500 0C, and expands to 0.3MPawhere some steam is extracted and fed to the feedwater heater. The remainder expands through the second-stage turbine and exits at the condenser pressure of 0.01 MPa. Saturated liquid at 0.3 MPaleaves the open feedwater heater. If the net power output of the cycle is 100 MW,and the turbine stages and pumps are isentropic, determine (a) the thermal efficiency, and(b) the mass flow rate of steam entering the first turbine, in kg/h.
Steam enters the first turbine stage of a vapor power cycle with reheat and regeneration at 15 MPa, 500 0C, and expands to 2 MPa. A portion of the flow is diverted to a closed feedwater heater at 2 MPa, and the remainder is reheated to 500 0C before entering the second turbine stage. Expansion through the second turbine stage occurs to 1 MPa, where another portion of the flow is diverted to a second closed feedwater heater at 1 MPa. The remainder of the flow expands through the third turbine stage to 0.10 MPa, where a portion of the flow is diverted to an open feedwater heater operating at 0.10 MPa, and the rest expands through the fourth turbine stage to the condenser pressure of 10 kPa. Condensate leaves each closed feedwater heater as saturated liquid at the respective extraction pressure. The feedwater streams leave each closed feedwater heater at a temperature equal to the saturation temperature at the respective extraction pressure. The condensate streams from the closed heaters…
In a reheat-regenerative steam cycle, steam enters the h.p. turbine at 80 bar, 480 °C andexpands to 7 bar. The steam is then reheated to 440 °C before entering the l.p. turbine,where it expands to the condenser pressure of 0.08 bar. Steam extracted from the h.p.turbine at 20 bar is fed to a closed feedwater heater, from which the drain at 205 °C iscascaded to an open feedwater heater through a trap. Steam extracted from the l.p. turbineat 3 bar is also fed into the open feedwater heater, from which the total flow is pumpedinto the steam generator. The net power output of the cycle is 100 MW. Assuming idealprocesses, determine (a) the cycle efficiency, and (b) the rate of steam generation in kg/h.[Ans. (a) 43%, (b) 2.8 × 105 kg/h]
In a reheat cycle steam at 15 MPa, 540°C enters the engine and expands to 1.95 MPa. At this point the steam is withdrawn and passed through a reheater. It reenters the engineat 540°C. Expansion now occurs to the condenser pressure of 0.0035 MPa. (a) A 60,000 kw turbine operates between the same state points except that the steam enters the reheater at 1.95 MPa and 260°C, departs at 1.8 MPa and 540°C. The steam flow is 147,000 kg/hr, generator efficiency is 96%. For actual engine, find, ek, mk, and nk, (b) Determine the approximate enthalpy of the exhaust steam if the heat lost through the turbine casing is 2% of the combined work.