A steam power plant operating on regenerative cycle, as illustrated in Fig 8.5, includs just one feedwater heater. Steam enters the turbine at 650 psia and 900oF and exhaust at 1 psia. Steam for the feedwater heater is extracted from the turbine at 50 psia, and in condensing raises the temperature of the feedwater to within 11oF of its condensation temperature at 50 psia. If the turbine and pump efficiencies are both 0,78, what is the thermal efficiency of the cycle and what fraction of the steam entering the turbine is extracted for the feedwater heater

A steam power plant operating on regenerative cycle, as illustrated in Fig 8.5, includs just one feedwater heater. Steam enters the turbine at 650 psia and 900oF and exhaust at 1 psia. Steam for the feedwater heater is extracted from the turbine at 50 psia, and in condensing raises the temperature of the feedwater to within 11oF of its condensation temperature at 50 psia. If the turbine and pump efficiencies are both 0,78, what is the thermal efficiency of the cycle and what fraction of the steam entering the turbine is extracted for the feedwater heater

Refrigeration and Air Conditioning Technology (MindTap Course List)

8th Edition

ISBN:9781305578296

Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Publisher:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Chapter41: Troubleshooting

Section: Chapter Questions

Problem 8RQ: When the outside ambient air temperature is 90F, the temperature of the condensing refrigerant in a...

See similar textbooks

Similar questions

The operating condition for the single compressor in a household refrigerator is the lowest box temperature, which is typically A. 0F B. -20F C. 20F D. 40F
When the outside ambient air temperature is 90F, the temperature of the condensing refrigerant in a standard- efficiency unit should be approximately A. 120F. B. 130F. C. 140F. D. 150F.
Why heat engines are intentionally equated at high temperatures?
A jet plane is flying at a speed of 1000 km/h. The ambient air pressure and temperature are 0.85 bar and 30 °C, respectively. The cockpit is to be maintained at 25 °C and 1 bar by using an air refrigeration system. The cooling load of the cockpit is (12 + 0.01 × X) TR. Ram efficiency is 90%. The compressor operates at an efficiency of 80% to increase the pressure by 5 times. The Isentropic efficiency of the cooler turbine is 85%. Pressure drop in the heat exchanger is 0.2 bar. Temperature of air leaving the heat exchanger and entering the cooling turbine is 50 °C. Find the quantity of air passed through the cooling turbine and COP of the system. X = 63 Last 3 digits of your student ID.
An R-12 refrigeration system using a single compressor serves three evaporators of 50, 30 and 20 tons capacity in parallel to each other with an evaporating temperatures of 0 C(hg = 351.447 KJ/kg), -5 C(hg = 349.321 KJ/kg) and -10 C(hg = 347.134 KJ/kg), respectively. If the condenser is maintained at 40 C(hf = 238.535 KJ/kg), compute the COP of the system. Enthalpy at the end of compression is at 378 KJ/kg.
A refrigerating system having a 2-Stage Compression with Flash gas removal and intercooling (without water intercooler) operates under pressure limits of 1200kPa and 30kPa and uses R22 as a refrigerant. If the heat to be rejected by the condenser is equal to 185kJ/s and the COP of the system is 327%, determine the following: a.Total work of Compression in kW b. Individual work of compressor kW c.Refrigerating Effect in TOR d. Mass flowrate in the high-pressure and low-pressure loop of the system in kg/s e. Mass flow rate (kg/s) flowing in the high lower pressure loops of the system
Can you also show the T-S and P-H diagram? REF134A A Single Stage Vapor Compression (SSVC) refrigeration system has a cooling capacity of 6 tons. The discharge of the evaporator is at -20°C & 0.1 MPa and the discharge of the condenser is at 30°C & 1.0 MPa. Determine the following: (a) the COP of the system, (b) the Energy Efficiency Ratio in kJ/hr/W, (c) the HP/ton of the system, (d) the Refrigerating Efficiency of the system.
In a steam power plant, the condenser pressure is 10 kPa. The turbine and pump isentropic efficiencies are both 85 %. Draw the schematic and T-S diagrams. Label the points by setting point 1 at the condenser outlet, point 2 at the pump outlet, point 3 at the boiler outlet, and point 4 at the turbine outlet. Use the label 2a and 4a for the points due to the isentropic efficiency of the pump and turbine, respectively. Use 2 decimal places for the enthalpy and other energies in solving and for the final answers. For the steam quality (x) and entropy (s), use 4 decimal places in solving. For the specific volume, use 6 decimal places. The pressure and the temperature of steam that enters the turbine are 4.5 MPa and 800 oC Determine the following: (INPUT YOUR ANSWERS ON THE BLANK SPACES PROVIDED.) Enthalpy at point 1 in kJ/kg = Enthalpy at point 2 in kJ/kg = Enthalpy at point 3 in kJ/kg = Enthalpy at point 4 in kJ/kg = Actual Enthalpy at point 2a in kJ/kg = Actual Enthalpy at point…
In a steam power plant, the condenser pressure is 10 kPa. The turbine and pump isentropic efficiencies are both 85 %. Draw the schematic and T-S diagrams. Label the points by setting point 1 at the condenser outlet, point 2 at the pump outlet, point 3 at the boiler outlet, and point 4 at the turbine outlet. Use the label 2a and 4a for the points due to the isentropic efficiency of the pump and turbine, respectively. Use 2 decimal places for the enthalpy and other energies in solving and for the final answers. For the steam quality (x) and entropy (s), use 4 decimal places in solving. For the specific volume, use 6 decimal places. The pressure and the temperature of steam that enters the turbine are 4 MPa and 700 oC (use the given values assigned on your name in the table below) Determine the following: Enthalpy at point 1 in kJ/kg= Enthalpy at point 2 in kJ/kg = Enthalpy at point 3 in kJ/kg = Enthalpy at point 4 in kJ/kg = Actual Enthalpy at point 2a in kJ/kg= Actual Enthalpy at…
A gas turbine power plant has an output of 12,500kW with electrical and mechanical loss of 900kW. The overall thermal efficiency of the unit is 30 percent. The gas turbine exhausts to a waste heat recovery boiler which is 75 percent efficient. The steam from the boiler drives a steam turbine-generator which has an overall heat rate of 10,200 kJ/kW·hr. Steam turbine unit auxiliaries require 950kW. Determine the following: 1. The thermal efficiency, in percent, of the Steam Turbine generator plant. a. 53.9 b. 155.7 c. 31.9 d. 91.1 e. 18.8 2. The overall thermal efficiency in percentile (%). a. 155.7 b. 31.9 c. 91.1 d. 18.8 e. 53.9 3. The net heat rate, in kJ/kW·hr, of the combined cycle. a. 3,404.92 b. 4,766.89 c. 6,673.65 d. 2,432.09 e. 9,343.11
In a certain refrigeration system for low temperature application , a two- stage operation isdesirable which employs ammonia system that serves a 30 ton evaporator at -30 OC .The systemuses a direct contact cascade condenser and the condenser temperature is 40 OC . How muchbigger is the mass of the high pressure loop compared to the mass of the low pressure loop?A) 0.112 kg/sec B) 11.38 ??/???C) 1.56 ??/???D) 0.26 kg /sec
A compressor on a refrigeration system used R-22 as the working fluid. The refrigerant enters the compressor at 70 psia/40 F and exits the compressor at 180 psig/200 F. What is the isentropic efficiency of the compressor? Answers: 54% 70% 48% 65% 60% 42%