A schematic of a combined refrigeration cycle and a portion of a steam power cycle is shown in the figure below. In the power cycle, steam (water) with a mass flow rate m, enters the turbine at state 1. A portion of the steam (m₂) exits the turbine at state 2 before passing through the mixing chamber. The remainder (m3 = 3 kg/s) exits the turbine at state 3 and then enters a heat exchanger where it is cooled by the refrigeration cycle. The water leaves the heat exchanger at state 4 as a saturated liquid and then is pumped up to the mixing chamber pressure. R-134a with a mass flow rate of me is used in the refrigeration cycle to provide cooling to the water in the heat exchanger. Properties at each state are given in the figure below. Assume that the compressor, turbine, pump, mixing chamber, throttling valve and outer walls of the heat exchanger are well insulated and neglect changes in potential and kinetic energy across all devices.

A schematic of a combined refrigeration cycle and a portion of a steam power cycle is shown in the figure below. In the power cycle, steam (water) with a mass flow rate m, enters the turbine at state 1. A portion of the steam (m₂) exits the turbine at state 2 before passing through the mixing chamber. The remainder (m3 = 3 kg/s) exits the turbine at state 3 and then enters a heat exchanger where it is cooled by the refrigeration cycle. The water leaves the heat exchanger at state 4 as a saturated liquid and then is pumped up to the mixing chamber pressure. R-134a with a mass flow rate of me is used in the refrigeration cycle to provide cooling to the water in the heat exchanger. Properties at each state are given in the figure below. Assume that the compressor, turbine, pump, mixing chamber, throttling valve and outer walls of the heat exchanger are well insulated and neglect changes in potential and kinetic energy across all devices.

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

Ts diagrams for two reversible thermodynamic power cycles are shown in the following figure. Both cycles operate between a high temperature reservoir at 500 K and a low temperature reservoir at 300 K. The process on the left is the Carnot cycle described in Section 2.9. The process on the right is a Stirling cycle, which is similar to a Carnot cycle, except that the two steps (state 4 to state 1) and (state 2 to state 3) are at constant volume. Which cycle, if either, has a greater efficiency? Explain.
In an ideal vapor-compression refrigeration cycle, the refrigerant enters the compressor as a saturated vapor and is cooled to the saturated liquid state in the condenser. It is then throttled to the evaporator pressure and vaporizes as it absorbs heat from the refrigerated space. Figure Q3.1 depicts the description of this process. Warm environment QH Condenser Expansion valve Compressor Evaporator Cold refrigerated space Figure Q3.1: Ideal vapor-compression refrigeration cycle. Assuming a refrigerator operates on this principle and uses refrigerant-134a as the working fluid, answer the following questions. (a) The condenser operates at 1.6 MPa and the evaporator at -6°C. If an adiabatic, reversible expansion device was available and used to expand the liquid leaving the condenser, (i) Calculate the COP improve by using this device instead of the throttle device. (ii)Illustrate a T-s diagram that represents the ideal vapor-compression refrigeration cycle described in (a)
Separate streams of steam and air flow through the turbine and heat exchanger arrangement shown in the figure below, where air enters location 5 at a rate of 1000 kg/min. The left turbine (Turbine 1) is able to produce 12,000 kW of power. Steady-state operating data are provided on the figure. Heat transfer with the surroundings can be neglected, as can all kinetic and potential energy effects. W2 = ? Turbine Turbine 2 P3 = 10 bar T3 = ? T2 = 400°C_ P2= 10 bar T = 240°C P4 = 1 bar Steam in P1 = 20 bar +6 T = 600°C www T5 = 1500 K -5 Ps = 1.35 bar Heat exchanger V T = 1200 K P6 = 1 bar Air in Determine: T3, in °C. • the mass flow rate of steam at 1, in kg/s. • the power output of the second turbine, in kW. • the magnitude of heat transfer between the steam and air, in kW. • the direction of the heat transfer (i.e., to the steam or from the steam).
Referring to the reversible heat pump cycle shown in the figure, p₁ = 14.7 lb/in², p4 = 20.3 lb/in², v₁ = 12.6 ft³/lb, v4 = 10.0 ft³/lb, and the gas is air obeying the ideal gas model. P4 P1 Determine TH, in °R, and the coefficient of performance. V4 VI TH V
Referring to the reversible heat pump cycle shown in the figure, p₁ = 14.7 lby/in². Pa = 34.7 lb/in², v₁ = 12.6 ft3/lb, v4 = 7.0 ft³/lb, and the gas is air obeying the ideal gas model. Step 1 Determine TH. in °R, and the coefficient of performance. Determine TH. in °R. TH= i Save for Later P4 °R PI V4 VI Ty Attempts: 0 of 4 used Submit Answer Activa Go to Se
Air within a piston-cylinder assembly executes a Carnot heat pump cycle, as shown in the figure below. For the cycle, TH = 600 K and Tc = 300 K. The energy rejected by heat transfer at 600 K has a magnitude of 1000 kJ per kg of air. The pressure at the start of the isothermal expansion is 325 kPa. p-v diagram for a Carnot gas refrigeration or heat pump cycle. Assuming the ideal gas model for the air, determine: (a) the magnitude of the net work input, in kJ per kg of air, and (b) the pressure at the end of the isothermal expansion, in kPa.
Referring to the reversible heat pump cycle shown in the figure, p₁ = 14.7 lb/in², p = 41.5 lb/in², v₁ = 12.6 ft³/lb, v4 = 6.0 ft³/lb, and the gas is air obeying the ideal gas model. Step 1 Determine TH, in °R, and the coefficient of performance. Determine TH, in °R. TH= i P4 ºR P1 V4 VI 3 Tμ V
Superheated steam at 18 MPa, 560 °C enters the steam turbine. The pressure at the exit of the turbine is 0.06 MPa and saturated liquid water leaves the condenser at 0.06 MPa. Pressure is increased to 18 MPa again after the pump. Find: (a) Sketch the process on a T-s diagram. (b) The net work per unit of steam flow in kJ/kg. (c) Heat transfer to steam passing through the boiler, in kJ/kg.
Regenerative steam power plant shown in figure below employs two feed heaters which are optimally placed such that cycle has the maximum thermal efficiency. The mass of steam generated is 16 kg/s. The feed water leaves each heater as saturated liquid at corresponding bleed pressure. Neglect the pumps work and find: a. Cycle thermal efficiency. b. Specific steam consumption. c. Mechanical efficiency of the turbine-generator gearing unit. Draw the equivalent (T-s) diagram considering an ideal cycle. 70 bar 450°C Gearing unit Generator 15 MW Turbine Super heater Boiler Condenser 0.07 bar Open heater Closed heater Pump Pump Throttling Valve
In an ideal vapor-compression refrigeration cycle, the refrigerant enters the compressor as a saturated vapor and is cooled to the saturated liquid state in the condenser. It is then throttled to the evaporator pressure and vaporizes as it absorbs heat from the refrigerated space. Figure Q3.1 depicts the description of this process. Warm environment Condenser Win Expansion valve Compressor Evaporator Cold refrigerated space Figure Q3.1: Ideal vapor-compression refrigeration cycle. (b) The same working fluid enters the condenser that operates between 0.14 to 0.8 MPa, and flow rate of refrigerant is 0.05 kg/s, Evaluate the rate of heat removal from the refrigerated space and the power input to the compressor. (i) (ii) Analyze the rate of heat rejection to the environment. (iii) Determine the COP of the refrigerator for this process. (iv) Predict the power input if the throttling valve is replaced by an isentropic turbine. Justify on the difference on the power input measured between…
A Simple Steam Power Plant under the conditions shown in the diagram. Neglect Kinetic Energy and Potential Energy across the power plant and neglect the heat transfer from the turbine. Choose the correct answers The power done by the turbine = 12 MW. The heat supplied to Boiler = 25.7 MW The power done by the turbine = 10 MW. The heat supplied to Boiler = 15.7 MW The power done by the turbine 12 MW. The heat supplied to Boiler = 45.7 MW The power done by the turbine 8 MW. The heat supplied to Boiler = 25.7 MW
Air within a piston-cylinder assembly executes a Carnot heat pump cycle, as shown in the figure below. For the cycle, TH = 400 K and Tc = 300 K. The energy rejected by heat transfer at 400 K has a magnitude of 625 kJ per kg of air. The pressure at the start of the isothermal expansion is 325 kPa. TH Te p-v diagram for a Carnot gas refrigeration or heat pump cycle. Assuming the ideal gas model for the air, determine: (a) the magnitude of the net work input, in kJ per kg of air, and (b) the pressure at the end of the isothermal expansion, in kPa.