$(40$ pts$.)$ Consider a combustion in a boiler in which the fuel is an equimolar mixture of ethane

$(C_2{H}_6)$ and methane $(C{H}_4)$ and an equivalence ratio of $0\mathrm{.}8.$

a$.$ Using the data in Appendix A$,$ estimate the adiabatic constant$-$pressure flame

temperature for a boiler. Assume complete combustion to $C{O}_2$ and $H_{2}O$ and neglect

any dissociation. The boiler operates at $1$ atm $,$ and both air and fuel enter at $298$ K $.$

i$.$ Use average specific heats for your calculations. Start by evaluating them at

a temperature of $1,200$ K$.$ Perform one corrective iteration: once you have a

first estimate of the flame temperature, reevaluate the specific heats at a

more appropriate average temperature, and find a better estimate of the

flame temperature.

ii$.($EXTRA credit$)$ Use the full paper tables $($or the computerized tables$)$ to find

the flame temperature.

b$.$ Estimate the adiabatic constant$-$volume flame temperature for the combustion.

Also, determine the final pressure for constant$-$volume combustion.

i$.$ Use average specific heats for your calculations. Start with a $($reasonable$)$

estimate of the flame temperature that is equal to the constant$-$pressure

result rounded up to a convenient number. Perform one corrective iteration.

ii$.($EXTRA credit$)$ Use the full paper tables $($or the computerized tables$)$ to find

the flame temperature. $($for refernace the book is An Introduction to Combustion: Concepts and Applications$,$ by Stephen Turns and Daniel$)$

C$.$ Haworth