Recent content by Andy86

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    Calculate steam raised per hour

    @Chestermiller I was only joking! Thanks for stepping in, I have now completed all my thermodynamics modules. VERY steep learning curve. Thanks for all the help! @jim hardy Thank you also for the guidance! Off to sit in a darkened room for 3 hours! Thanks Andy
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    Calculate steam raised per hour

    @Chestermiller Thanks Chester- that completely blows my calculations out the water! Back to square 1 we go!
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    Calculate steam raised per hour

    Apologies Jim, I am not sure what point your are trying to make? The question asks me for the Mass of the steam over an hour. Using the information I have I came up with M = 101.8 KG / H. Have I used an incorrect value somewhere?> I thought the heat capacity of water was constant @ 4.2 KJ /KG up...
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    Calculate steam raised per hour

    Thanks for the constructive criticism >>> Correction... How much energy comes out when you cool a kg of flue gas from 1997 to 300 degrees? Mass = 28.9 g per mol of flue gas Flow rate = 1400 Kmol / hour Mass flow rate = 28.9g * (1400 * 1000) = 39, 886 KG / hour...
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    Calculate steam raised per hour

    Thanks BvU & Jim, is this lot any closer? Thanks Andy Heat capacities of the flue gases at 1997°C / 2270K Co2 = 1.3865 KJ/KG H2O = 2.41267 KJ/KG O2 = 1.1999 KJ/KG N2 = 1.2985 KJ/KG Mass = Nmols * Molecular Mass Co2 = 3.9mols * 44 = 171.6g H2O = 4.75mols * 18 = 85.5g O2 = 0.6mols * 32 =...
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    Calculate steam raised per hour

    Sorry heat capacity of flue gas
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    Calculate steam raised per hour

    Homework Statement A fuel gas consists of 75% butane (C4H10), 10% propane (C3H8) and 15% butene (C4H8) by volume. It is to be fed to the combustion chamber in 10% excess air at 25ºC, where it is completely burnt to carbon dioxide and water. The flue gases produced are to be used to generate 5...
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    Calculating CV of Fuel/Air Mixture @ 25°C

    Ok Great, thanks for all your help Chester I really appreciate it. Andy
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    Calculating CV of Fuel/Air Mixture @ 25°C

    VERY! :-) So..... NET CV BY MASS n = PV / RT = 100000 * 1 / 8.314 * 298 = 40.3 MOL = 0.0403 KMOL CV = MK M^-3 / KMOL = 3.05 MJ M^-3 / 0.0403 KMOL = 75.6 MJ KMOL^-1 ?
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    Calculating CV of Fuel/Air Mixture @ 25°C

    NET CV BY VOL = 103.2MJ / M^-3 103.2 / 33.8 = 3.05MJ / M^-3
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    Calculating CV of Fuel/Air Mixture @ 25°C

    Meaning?
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    Calculating CV of Fuel/Air Mixture @ 25°C

    It doesn't look right that the CV is 3.12 MJ / m^3 as the gross CV is 108.1 MJ M^3, my calculated NET CV of 103.2 MJ M^3 looks more realistic?
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    Calculating CV of Fuel/Air Mixture @ 25°C

    That's the incorrect number of total mols in the mix, total ,mols is 33.8 > 34 Mols
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    Calculating CV of Fuel/Air Mixture @ 25°C

    Any thoughts?
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    Calculating CV of Fuel/Air Mixture @ 25°C

    EXCELLENT! how does this net CV by mass look... NET CV BY MASS n = PV / RT = 101300 * 1 / 8.314 * 298 = 40.0 mol = 0.0408 kmol CV = CV in MJ M^-3 / kmol M^3 = 103.2 MJ M^-3 / 0.0408 kmol = 2529.4 MJ kmol^-1 @ 25°C ??