Monday, January 01, 2007

HW #1, 6.62 - Real and Ideal Work from the Isentropic Expansion of Ethane in a Turbine - 12 pts

A stream of ethane gas at 220oC and 30 bar expands isentropically in a turbine to 2.6 bar. Determine the temperature of the expanded gas and the work produced if the properties of ethane are calculated by:
a.) The ideal gas EOS
b.) The SRK EOS

3 comments:

Anonymous said...

I am really lost on part b. I got part a. I am lost on where T2 came from. cause its lower than T2 of part a and i would think that would be a bigger temp drop would creat more ideal work and i calculated work with the temp that is given and it gives much more ideal work with that temp and even with the Hr correction it doesn't end being as low as the awnser. HELP!

Anonymous said...

i gots it i was leaving a step out

Anonymous said...

Brendan 5:03 and 8:08
I am glad you got it.
T2 is the temperature of the gas leaving the turbine.
T2 real gas is lower than T2 IG.
Sr < 0 and Sr at the inlet < Sr outlet
Because Sr1 is a big negative number, S1 is much lower. As a reult, T2 must be lower if the turbine is really isentropic.
Wsh real gas < Wsh IG also.