THERMODYNAMICS: ENG APPROACH LOOSELEAF
9th Edition
ISBN: 9781266084584
Author: CENGEL
Publisher: MCG
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Chapter 15.7, Problem 54P
Consider a complete combustion process during which the reactants enter the combustion chamber at 20°C and the products leave at 700°C. Combustion is achieved with (a) 100 percent theoretical air, (b) 200 percent theoretical air, and (c) the chemically correct amount of pure oxygen. For which case will the amount of heat transfer be the lowest? Explain.
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N₁
hc=Hp-HR=Nphp-ENRIR
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Liquid propane (C 3 H 8 ) enters a combustion chamber at 25 °C at a rate of 0.05
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Chapter 15 Solutions
THERMODYNAMICS: ENG APPROACH LOOSELEAF
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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- Liquid propane (C3H8) enters a combustion chamber at 25°C at a rate of 0.07 kg/min where it is mixed and burned with 40 percent excess air that enters the combustion chamber at 7°C. An analysis of the combustion gases reveals that all the hydrogen in the fuel burns to H,0 but only 75 percent of the carbon burns to CO, with the remaining 25 percent forming CO. determine (a) the balanced equation for actual combustion process and (b) the mass flow rate of air.arrow_forwardA 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.arrow_forwardComplete Combustion of methane with theoretical air (or 100% air) methane, C H, is to be burned with 100% air for complete combustion. The products of combustion or flue gas is at 105 kPa and 950 C Find (a) write the balanced mol equation (b) mass of theoretical air (c) mass of fuel (d) theoretical air-fuel ratio (e) volumetric analysis and molar analysis of wet flue gas (f) mass and volume of wet flue gas (g) gravimetric analysis of wet flue gas (h) dew point of wet flue gas (i) volumetric analysis and molar analysis of dry flue gas (j) mass and volume of dry flue gas (k) gravimetric analysis of dry flue gasarrow_forward
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