16-4M A proposed air-standard cycle begins at 1.1 bars, 37°C, and 0.808 m³/kg. Process 1-2 is isentro- pic compression to 3.2 bars: process 2-3 is constant-pressure heating to 1050 K and 0.940 m³/kg; process 3-4 is constant-volume cooling to 1.1 bars; process 4-1 is constant-pressure cooling to the initial state, (4) Sketch Pv and Ts diagrams of the cycle. (b) Determine the amount of heat added and the net work output, in kJ/kg. (c) Compute the thermal efficiency. (d) What is the Carnot efficiency for a heat engine with the same maximum and minimum temperatures as the above cycle? Use air-table data.

16-4M A proposed air-standard cycle begins at 1.1 bars, 37°C, and 0.808 m³/kg. Process 1-2 is isentro- pic compression to 3.2 bars: process 2-3 is constant-pressure heating to 1050 K and 0.940 m³/kg; process 3-4 is constant-volume cooling to 1.1 bars; process 4-1 is constant-pressure cooling to the initial state, (4) Sketch Pv and Ts diagrams of the cycle. (b) Determine the amount of heat added and the net work output, in kJ/kg. (c) Compute the thermal efficiency. (d) What is the Carnot efficiency for a heat engine with the same maximum and minimum temperatures as the above cycle? Use air-table data.

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

Chapter28: Special Refrigeration Applications

Section: Chapter Questions

Problem 15RQ: Why is two-stage compression popular for extra-low-temperature refrigeration systems?

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answer Part 2,3 and 4 only, thanks. An air-standard Carnot cyclewith a pressure and temperature at the beginning of isothermal expansion of 1.2MPa and 380 oC, respectively. The cycle operates with isothermalexpansion ratio of 6 and adiabatic expansion ratio of 3. If the cycle utilizes0.5 kg/s of air, determine: The heat added The heat rejected The thermal efficiency The mean effective pressure
PART D only A gas-turbine power generator operates on an ideal air-standard Brayton cycle 1 → 2 → 3 → 4 shown in Fig. 1. The gas temperatures at the compressor inlet, compressor exit, and turbine inlet are T1 = 300 K, T2 = 600 K, and T3 = 1200 K, respectively. Solve PART D below using the variable specific heat assumption PART D - Evaluate the thermal efficiency η of the cycle and the back work ratio rBW = wC/wT.
A thermodynamic cycle uses 0.5 kg of air works in a three-process air-standard power cycle:Process 1-2: Isothermal expansionProcess 2-3: Constant volumeProcess 3-1: Isentropic, k=1.4Given: Pressure and temperature at the end of constant volume process is P3=100 kPa andT3=300K, respectively. If the isentropic compression ratio is 6.0, determine:(a) The pressure, volume and temperature at each state points of the cycle.(b) The heat added and rejected throughout the cycle, in kJ(c) The work net output, in kJ(d) The thermal efficiency.(e) Illustrate the cycle in Pv and Ts coordinates.(Ans. Q1-2=157.95 kJ, Q2-3=-112.93 kJ, Q3-1=0, 45 kJ, 28.5%) Just answer D and E
PART B ONLY A gas-turbine power generator operates on an ideal air-standard Brayton cycle 1 → 2 → 3 → 4 shown in Fig. 1. The gas temperatures at the compressor inlet, compressor exit, and turbine inlet are T1 = 300 K, T2 = 600 K, and T3 = 1200 K, respectively. Solve the problem below using the variable specific heat assumption. PART B - Determine the pressure ratio rp = P2/P1 and the temperature at the turbine exit, T4 (in K).
THERMODYNAMICS Consider an air-standard Otto cycle with a heat addition of 800 Btu/bm of air, a compression ratio of 7, and a pressure and temperature at the start of the compression process of 13 lbf/in2, 50 F to simulate an actual spark-ignition engine. Determine the maximum pressure and temperature of the cycle, the thermal efficiency of the cycle, and the mean effective pressure assuming the variation of specific heat with the value from table A-19E Show Complete solution on a paper.
Part C only A gas-turbine power generator operates on an ideal air-standard Brayton cycle 1 → 2 → 3 → 4 shown in Fig. 1. The gas temperatures at the compressor inlet, compressor exit, and turbine inlet are T1 = 300 K, T2 = 600 K, and T3 = 1200 K, respectively. Solve Part C below using the variable specific heat assumption. Part C - Determine the heat input qin in the process 2 → 3, the work wC used by the compressor, and the work wT produced by the turbine per kg of air.
Pls answer thank you! The following data were obtained during performance test with a simple open cycle gas turbine engine: compressor inlet temperature, 520*R: compressor isentropic discharge temperature, 672"R: actual compressor discharge temperature, 691"R: turbine inlet temperature, 1500 R: turbine isentropic discharge temperature. 1184"R: and turbine actual discharge temperature, 1216°R. For these conditions calculate the thermal efficiency in percent.
A four-cylinder, four-stroke internal combustion engine operates at 2800 RPM. The processes within each cylinder are modeled as an air-standard Otto cycle with a pressure of 14.7 lbf/in2, a temperature of 80°F, and a volume of 0.03 ft3 at the beginning of compression. The compression ratio is 11, and maximum pressure in the cycle is 1080 lbf/in2. Use a cold air-standard analysis with k = 1.4. Determine the power developed by the engine, in horsepower, and the mean effective pressure in lbf/in^2.
A four-cylinder, four-stroke internal combustion engine operates at 2800 RPM. The processes within each cylinder are modeled as an air-standard Otto cycle with a pressure of 14.7 lbf/in2, a temperature of 80°F, and a volume of 0.02 ft3 at the beginning of compression. The compression ratio is 11, and maximum pressure in the cycle is 1080 lbf/in2. Use a cold air-standard analysis with k = 1.4. Determine the power developed by the engine, in horsepower.
an otto cycle operating in an air standard conditions has a peak tempearture of 800C. If the heat added in each cycle is equal to 350kj/kg. Determine the compression ratio of the cycle
The events of the Frick, split -stage , low temperature refrigerating cycle are as follows : AFreon-12 vapor compression system operates between O deg F and 90 deg F with saturatedliquid on the high side of the expansion valve and saturated vapor entering the compressorwhose volumetric efficiency is 88% . An NH3 compression operates between -63.11 deg F and11.66 deg F with saturated liquid entering the expansion valve and saturated vapor enteringthe compressor whose volumetric efficiency is 85% .The Freon -12 evaporator serves as thecondenser for the NH3 . For the ideal cycle and 1 ton of refrigeration , find the totalhorsepower required for compression efficiencies of 85% .A) 2.187 B) 2.96 C) 3.96 D) 1.6
An engine operating on the air standard heat engine has a compression ratio of 18. If the maximum cycle pressure at Isobaric heat addition is 55 bar, maximum and minimum cycle temperatures are 1893 K and 48oC, respectively. Determine: The amount of heat absorbed and heat rejected The efficiency of the cycle The mean effective pressure