EBK THERMODYNAMICS: AN ENGINEERING APPR
8th Edition
ISBN: 9780100257054
Author: CENGEL
Publisher: YUZU
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Textbook Question
Chapter 15.7, Problem 124FEP
One kmol of methane (CH4) is burned with an unknown amount of air during a combustion process. If the combustion is complete and there is 1 kmol of free O2 in the products, the air–fuel mass ratio is
(a)
34.6
(b)
25.7
(c)
17.2
(d)
14.3
(e)
11.9
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N₁
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Acetylene (C2H2) is burned with the stoichiometric amount of air during a combustion process. Assume complete combustion.
Part A
Determine the air-fuel ratio on a mass basis.
Part B
Determine the air-fuel ratio on a mole basis.
Part C
What-if scenario: What would the air to fuel ratio on a mass basis be if propene (C3H6) was burned instead of acetylene?
C4Hs is burned in an engine with a fuel-rich air-fuel ratio. Dry analysis of
the exhaust gives the following volume percents: CO2 = 14.95%, C4H8
0.75%, CO = 0%, H2 = 0%, O2 = 0%, with the rest being N2. Higher heating
value of this fuel is QHHV = 46.9 MJ/kg. Write the balanced chemical
equation for one mole of this fuel at these conditions. Calculate;
a) Air-fuel ratio.
b) Equivalence ratio.
c) Lower heating value of fuel. [MJ/kg]
d) Energy released when one kg of this fuel is burned in the engine with
a combustion efficiency of 98%. [MJ]
Chapter 15 Solutions
EBK THERMODYNAMICS: AN ENGINEERING APPR
Ch. 15.7 - How does the presence of N2 in air affect the...Ch. 15.7 - Prob. 2PCh. 15.7 - Prob. 3PCh. 15.7 - Is the airfuel ratio expressed on a mole basis...Ch. 15.7 - Prob. 5PCh. 15.7 - Prob. 6PCh. 15.7 - Prob. 7PCh. 15.7 - What does 100 percent theoretical air represent?Ch. 15.7 - Consider a fuel that is burned with (a) 130...Ch. 15.7 - Are complete combustion and theoretical combustion...
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. 14PCh. 15.7 - n-Butane fuel (C4H10) is burned with the...Ch. 15.7 - Prob. 16PCh. 15.7 - Prob. 17PCh. 15.7 - 15–18 n-Octane (C8H18) is burned with 50 percent...Ch. 15.7 - In a combustion chamber, ethane (C2H6) is burned...Ch. 15.7 - Prob. 20PCh. 15.7 - Prob. 21PCh. 15.7 - 15–22 One kilogram of butane (C4H10) is burned...Ch. 15.7 - 15–23E One lbm of butane (C4H10) is burned with 25...Ch. 15.7 - Prob. 24PCh. 15.7 - A fuel mixture of 60 percent by mass methane (CH4)...Ch. 15.7 - A certain natural gas has the following volumetric...Ch. 15.7 - Prob. 27PCh. 15.7 - A gaseous fuel with a volumetric analysis of 45...Ch. 15.7 - Prob. 30PCh. 15.7 - 15–31 Octane (C8H18) is burned with dry air. The...Ch. 15.7 - Prob. 32PCh. 15.7 - Prob. 33PCh. 15.7 - Prob. 34PCh. 15.7 - Prob. 35PCh. 15.7 - Prob. 36PCh. 15.7 - Prob. 37PCh. 15.7 - Prob. 38PCh. 15.7 - Prob. 39PCh. 15.7 - Prob. 40PCh. 15.7 - Prob. 41PCh. 15.7 - Prob. 42PCh. 15.7 - Prob. 44PCh. 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. 49PCh. 15.7 - Prob. 50PCh. 15.7 - Consider a complete combustion process during...Ch. 15.7 - Prob. 53PCh. 15.7 - Prob. 54PCh. 15.7 - Propane fuel (C3H8) is burned with an airfuel...Ch. 15.7 - 15–56 Hydrogen (H2) is burned completely with the...Ch. 15.7 - Prob. 57PCh. 15.7 - Prob. 58PCh. 15.7 - Octane gas (C8H18) at 25C is burned steadily with...Ch. 15.7 - Prob. 61PCh. 15.7 - Liquid ethyl alcohol [C2H5OH(l)] at 25C is burned...Ch. 15.7 - Prob. 63PCh. 15.7 - Prob. 64PCh. 15.7 - A constant-volume tank contains a mixture of 120 g...Ch. 15.7 - Prob. 67PCh. 15.7 - Prob. 68PCh. 15.7 - Prob. 69PCh. 15.7 - A fuel is completely burned first with the...Ch. 15.7 - Prob. 71PCh. 15.7 - Acetylene gas (C2H2) at 25C is burned during a...Ch. 15.7 - Octane gas (C8H18) at 25C is burned steadily with...Ch. 15.7 - Express the increase of entropy principle for...Ch. 15.7 - Prob. 81PCh. 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 - Benzene gas (C6H6) at 1 atm and 77F is burned...Ch. 15.7 - Prob. 87PCh. 15.7 - Prob. 88PCh. 15.7 - A steady-flow combustion chamber is supplied with...Ch. 15.7 - Prob. 91RPCh. 15.7 - 15–92 A gaseous fuel with 80 percent CH4, 15...Ch. 15.7 - Prob. 93RPCh. 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 - Prob. 100RPCh. 15.7 - A 6-m3 rigid tank initially contains a mixture of...Ch. 15.7 - Prob. 102RPCh. 15.7 - Propane gas (C3H8) enters a steady-flow combustion...Ch. 15.7 - Determine the highest possible temperature that...Ch. 15.7 - Prob. 106RPCh. 15.7 - Prob. 107RPCh. 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. 111RPCh. 15.7 - Prob. 112RPCh. 15.7 - Prob. 113RPCh. 15.7 - Consider the combustion of a mixture of an...Ch. 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. 123FEPCh. 15.7 - One kmol of methane (CH4) is burned with an...Ch. 15.7 - An equimolar mixture of carbon dioxide and water...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 - Prob. 129FEPCh. 15.7 - A fuel is burned during a steady-flow combustion...
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