Thermodynamics: An Engineering Approach
9th Edition
ISBN: 9781260048766
Author: CENGEL
Publisher: MCG
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Chapter 15.7, Problem 67P
A gaseous fuel mixture that is 40 percent propane (C3H8) and 60 percent methane (CH4) by volume is mixed with the theoretical amount of dry air and burned in a steady-flow, constant-pressure process at 100 kPa. Both the fuel and air enter the combustion chamber at 298 K and undergo a complete combustion process. The products leave the combustion chamber at 398 K. Determine
- (a) the balanced combustion equation,
- (b) the amount of water vapor condensed from the products, and
- (c) the required airflow rate, in kg/h, when the combustion process produces a heat transfer output of 97,000 kJ/h.
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Students have asked these similar questions
A gaseous fuel with 80% butane, 15% nitrogen and 5% oxygen (on a mole basis) is burned to completion with 120 percent theoretical air that enters the combustion chamber at 30°C and 100 kPa. Determine the volume flow rate of air required to burn fuel at a rate of 2 kg/min.
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N₁
hc=Hp-HR=Nphp-ENRIR
TABLE 32
Standard enthalpies of formation
Species
State!
0₁
Gas
Gav
Ga
Gas
Gas
Gas
H₁
C.
Co,
но
1,0
CO
Useful relations:
Mair
123 ful
C,H,
CH,OH
CH,OH
Liqind
Gas
Gas
Gas
Gas
Liquid
Gas
Liquid
AF
C₂B₁
сн..
At 298.15 K (25 C) and 1 aus
Ah,, MJ/kmol
0
0
0
0
-393.52
241.83
285.84
110.54
-74.87
-101.85
-201.17
238.58
208.45
249.35
Liquid octane is burned completely with 75% excess air. Determine the air-fuel ratio for this combustion process.
Chapter 15 Solutions
Thermodynamics: An Engineering Approach
Ch. 15.7 - What are the approximate chemical compositions of...Ch. 15.7 - How does the presence of N2 in air affect the...Ch. 15.7 - Prob. 3PCh. 15.7 - Prob. 4PCh. 15.7 - Is the airfuel ratio expressed on a mole basis...Ch. 15.7 - How does the presence of moisture in air affect...Ch. 15.7 - Prob. 7PCh. 15.7 - Prob. 8PCh. 15.7 - Prob. 9PCh. 15.7 - Are complete combustion and theoretical combustion...
Ch. 15.7 - What does 100 percent theoretical air represent?Ch. 15.7 - Consider a fuel that is burned with (a) 130...Ch. 15.7 - What are the causes of incomplete combustion?Ch. 15.7 - Which is more likely to be found in the products...Ch. 15.7 - Methane (CH4) is burned with the stoichiometric...Ch. 15.7 - Prob. 16PCh. 15.7 - n-Butane fuel (C4H10) is burned with the...Ch. 15.7 - Prob. 18PCh. 15.7 - Propane (C3H8) is burned with 75 percent excess...Ch. 15.7 - Propane fuel (C3H8) is burned with 30 percent...Ch. 15.7 - In a combustion chamber, ethane (C2H6) is burned...Ch. 15.7 - Prob. 22PCh. 15.7 - Prob. 23PCh. 15.7 - Ethane (C2H6) is burned with 20 percent excess air...Ch. 15.7 - Octane (C8H18) is burned with 250 percent...Ch. 15.7 - Prob. 26PCh. 15.7 - A fuel mixture of 60 percent by mass methane (CH4)...Ch. 15.7 - Prob. 28PCh. 15.7 - A certain natural gas has the following volumetric...Ch. 15.7 - Prob. 30PCh. 15.7 - A gaseous fuel with a volumetric analysis of 45...Ch. 15.7 - Prob. 33PCh. 15.7 - The fuel mixer in a natural gas burner mixes...Ch. 15.7 - Prob. 35PCh. 15.7 - Prob. 36PCh. 15.7 - Determine the fuelair ratio when coal from...Ch. 15.7 - Prob. 38PCh. 15.7 - Prob. 39PCh. 15.7 - Prob. 40PCh. 15.7 - Prob. 41PCh. 15.7 - When are the enthalpy of formation and the...Ch. 15.7 - Prob. 43PCh. 15.7 - Prob. 44PCh. 15.7 - Prob. 45PCh. 15.7 - Prob. 46PCh. 15.7 - Prob. 48PCh. 15.7 - Repeat Prob. 1546 for liquid octane (C8H18).Ch. 15.7 - Ethane (C2H6) is burned at atmospheric pressure...Ch. 15.7 - Reconsider Prob. 1550. What minimum pressure of...Ch. 15.7 - Calculate the HHV and LHV of gaseous n-octane fuel...Ch. 15.7 - Prob. 53PCh. 15.7 - Consider a complete combustion process during...Ch. 15.7 - Prob. 56PCh. 15.7 - Prob. 57PCh. 15.7 - Prob. 58PCh. 15.7 - Propane fuel (C3H8) is burned with an airfuel...Ch. 15.7 - Prob. 60PCh. 15.7 - Prob. 61PCh. 15.7 - Prob. 62PCh. 15.7 - Octane gas (C8H18) at 25C is burned steadily with...Ch. 15.7 - Liquid ethyl alcohol [C2H5OH(l)] at 25C is burned...Ch. 15.7 - Prob. 66PCh. 15.7 - A gaseous fuel mixture that is 40 percent propane...Ch. 15.7 - A constant-volume tank contains a mixture of 120 g...Ch. 15.7 - Prob. 70PCh. 15.7 - Prob. 71PCh. 15.7 - Prob. 72PCh. 15.7 - A fuel is completely burned first with the...Ch. 15.7 - Prob. 74PCh. 15.7 - Prob. 75PCh. 15.7 - What is the adiabatic flame temperature of methane...Ch. 15.7 - Octane gas (C8H18) at 25C is burned steadily with...Ch. 15.7 - Acetylene gas (C2H2) at 25C is burned during a...Ch. 15.7 - Ethyl alcohol [C2H5OH(g)] is burned with 200...Ch. 15.7 - Prob. 81PCh. 15.7 - Prob. 82PCh. 15.7 - Reconsider Prob. 1582. The combustion products are...Ch. 15.7 - Express the increase of entropy principle for...Ch. 15.7 - Prob. 85PCh. 15.7 - What does the Gibbs function of formation gf of a...Ch. 15.7 - Liquid octane (C8H18) enters a steady-flow...Ch. 15.7 - Prob. 88PCh. 15.7 - Reconsider Prob. 1588. The automobile engine is to...Ch. 15.7 - Benzene gas (C6H6) at 1 atm and 77F is burned...Ch. 15.7 - Prob. 91PCh. 15.7 - n-Octane [C8H18(l)] is burned in the...Ch. 15.7 - A steady-flow combustion chamber is supplied with...Ch. 15.7 - Prob. 94RPCh. 15.7 - Prob. 95RPCh. 15.7 - Prob. 96RPCh. 15.7 - Prob. 97RPCh. 15.7 - Prob. 98RPCh. 15.7 - Prob. 99RPCh. 15.7 - n-Butane (C4H10) is burned with the stoichiometric...Ch. 15.7 - A gaseous fuel mixture of 60 percent propane...Ch. 15.7 - Calculate the higher and lower heating values of...Ch. 15.7 - Prob. 103RPCh. 15.7 - Methane gas (CH4) at 25C is burned steadily with...Ch. 15.7 - A 6-m3 rigid tank initially contains a mixture of...Ch. 15.7 - Propane gas (C3H8) enters a steady-flow combustion...Ch. 15.7 - Determine the highest possible temperature that...Ch. 15.7 - Liquid propane [C3H8(l)] enters a combustion...Ch. 15.7 - Prob. 109RPCh. 15.7 - Prob. 110RPCh. 15.7 - Prob. 111RPCh. 15.7 - A steam boiler heats liquid water at 200C to...Ch. 15.7 - Repeat Prob. 15112 using a coal from Utah that has...Ch. 15.7 - Liquid octane (C8H18) enters a steady-flow...Ch. 15.7 - Prob. 115RPCh. 15.7 - Consider the combustion of a mixture of an...Ch. 15.7 - Prob. 117RPCh. 15.7 - A fuel is burned steadily in a combustion chamber....Ch. 15.7 - A fuel is burned with 70 percent theoretical air....Ch. 15.7 - Prob. 126FEPCh. 15.7 - One kmol of methane (CH4) is burned with an...Ch. 15.7 - The higher heating value of a hydrocarbon fuel...Ch. 15.7 - Acetylene gas (C2H2) is burned completely during a...Ch. 15.7 - An equimolar mixture of carbon dioxide and water...Ch. 15.7 - A fuel is burned during a steady-flow combustion...
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