Question

a. (4 pts) Explain conceptually why increasing air flow rate lowers the adiabatic flame temperature. b. (8 pts) Determine the theoretical moles of air necessary to completely combust 1 mol/sof

acetylene. c. (28 pts) Determine the unknown inlet and outlet specific enthalpies (and the heat of reaction if using heat of reaction method). To help your calculations, please use the inlet-outlet enthalpy table below and explicitly state your solution method and reference state(s) directly on this sheet!! (60 pts; 3 pages) Energy balance with reaction. Among common liquid fuels, acetylene(C2H2) torches burn at the highest adiabatic flame temperatures. It turns out that for our specific application we desire an outlet temperature of 1500°C, which is much cooler than the adiabatic flame temperature. 1500°C is enforced by using a large quantity of excess air.Assume that acetylene burns completely and clean and with a basis of calculation of 1mol/s, determine the % of excess air by solving an energy balance. The inlet acetylene and air gas streams are at 25°C and 1 atm, and the outlet is set at 1500°C and 1 atm. d. (12 pts) Write the appropriate form of the energy balance needed to solve for n1 – the unknown molar flow rate of air. Your answer should have n1 on the left hand side of the equation and all remaining knowns and unknowns on the process flow diagram on the right hand side.

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