The exhaust gases of a compression-ignition engine are to be used to drive an exhaust gas turbo-supercharger. Estimate the mean pressure ratio of expansion and the isentropic enthalpy drop per kmol of gas in the turbine if the mean exhaust temperature is \(600{ }^{\circ} \mathrm{C}\) and the isentropic temperature drop is \(100^{\circ} \mathrm{C}\). The composition of the exhaust gas by volume is \(\mathrm{CO}_{2}, 8 \% ; \mathrm{H}_{2} \mathrm{O}, 9.1 \% ; \mathrm{O}_{2}, 7.5 \% ; \mathrm{N}_{2}, 75.4 \%\).

The specific heats at constant volume in \(\mathrm{kJ} / \mathrm{kmol} \mathrm{K}\) are

The water vapour \(\left(\mathrm{H}_{2} \mathrm{O}\right)\) may be considered to act as a perfect gas. \([1.946 ;-4547.1 \mathrm{~kJ} / \mathrm{kmol}]\)

Transcribed Image Text:

02 32 +0.00257 N2 29+ 0.00257 HO 34 +0.087 CO 50+ 0.00677