Exercícios Resolvidos de Combustão: Estequiometria e Ponto de Orvalho

131 Ten grams of propane C3H8 burns with just enough oxygen O2 for complete combustion Determine the amount of oxygen required and the amount of combustion products formed each in grams 132 Ethane C2H6 burns completely with the theoretical amount of air Determine the airfuel ratio on a a molar basis b mass basis 1311 A natural gas with the molar analysis 944 CH4 34 C2H6 06 C3H8 05 C4H10 11 N2 burns completely with 20 excess air in a reactor operating at steady state If the molar flow rate of the fuel is 01 kmolh determine the molar flow rate of the air in kmolh 1320 A gaseous fuel mixture with a specified molar analysis burns completely with moist air to form gaseous products as shown in Fig P1320 Determine the dew point temperature of the products in C 1322 Propane C3H8 burns completely with 180 of theoretical air entering at 40C 1 atm 60 relative humidity Obtain the balanced reaction equation and determine the dew point temperature of the products in C when cooled at 1 atm 1323 Butane C4H10 burns completely with 160 of theoretical air at 20C 1 atm and 90 relative humidity Determine a the balanced reaction equation b the dew point temperature in C of the products when cooled at 1 atm 1324 Methane CH4 enters a furnace and burns completely with 150 of theoretical air entering at 25C 0945 bar 75 relative humidity Determine a the balanced reaction equation b the dew point temperature of the combustion products in C when cooled at 0945 bar 1346 Propane C3H8 at 298 K 1 atm enters a combustion chamber operating at steady state with a molar flow rate of 07 kmols and burns completely with 200 of theoretical air entering at 298 K 1 atm Kinetic and potential energy effects are negligible If the combustion products exit at 560 K 1 atm determine the rate of heat transfer for the combustion chamber in kW Repeat for an exit temperature of 298 K 1347 Methane CH4 at 25C 1 atm enters a furnace operating at steady state and burns completely with 140 of theoretical air entering at 400 K 1 atm The products of combustion exit at 700 K 1 atm Kinetic and potential energy effects are negligible If the rate of heat transfer from the furnace to the surroundings is 400 kW determine the mass flow rate of methane in kgs 1357 A closed rigid vessel initially contains a gaseous mixture at 25C 1 atm with the molar analysis of 20 ethane C2H6 80 oxygen O2 The initial mixture contains one kmol of ethane Complete combustion occurs and the products are cooled to 25C Determine the heat transfer in kJ and the final pressure in atm 1358 A mixture of 1 kmol of hydrogen H2 and n kmol of oxygen O2 initially at 25C and 1 atm burns completely in a closed rigid insulated container The container finally holds a mixture of water vapor and O2 at 3000 K The ideal gas model applies to each mixture and there is no change in kinetic or potential energy between the initial and final states Determine a the value of n b the final pressure in atm 1365 Liquid octane C8H18 at 25C 1 atm enters an insulated reactor operating at steady state and burns with 90 of theoretical air at 25C 1 atm to form products consisting of CO2 CO H2O and N2 only Determine the temperature of the exiting products in K Compare with the results of Example 138 and comment 1376 A mixture of gaseous octane C8H18 and 200 of theoretical air initially at 25C 1 atm reacts completely in a rigid vessel a If the vessel were wellinsulated determine the temperature in C and the pressure in atm of the combustion products b If the combustion products were cooled at constant volume to 25C determine the final pressure in atm and the heat transfer in kJ per kmol of fuel 1380 Pentane C5H12 gas enters a wellinsulated reactor at 25C 15 atm and reacts completely with excess air entering at 500 K 15 atm The products exit at 1800 K 15 atm For operation at steady state and ignoring kinetic and potential energy effects determine a the percent excess air b the rate of entropy production in kJK per kmol of pentane 1381 Ethylene C2H4 gas enters a wellinsulated reactor and reacts completely with 400 of theoretical air each at 25C 2 atm The products exit the reactor at 2 atm For operation at steady state and ignoring kinetic and potential energy effects determine a the balanced reaction equation b the temperature in K at which the products exit c the rate of entropy production in kJK per kmol of ethylene 1385 A gaseous mixture of ethane C2H6 and the theoretical amount of air at 25C 1 atm enters a reactor operating at steady state and burns completely Combustion products exit at 627C 1 atm Heat transfer from the reactor takes place at an average surface temperature of 327C Determine a the rate of entropy production within the reactor in kJK per kmol of fuel b the rate of exergy destruction within the reactor in kJ per kmol of fuel Kinetic and potential energy effects are negligible Let T0 25C