3 replies to this topic

[palaniappan]

How to get the value for isentropic exponent for a HC gas (Fuel gas)

I need this to find out the CV of a valve in the line for a vapour line using the online calculator in the following website.

http://tierling.home.texas.net/

Can any1 help on this.

[latexman]

If the properties of HC gas (Fuel gas) can be accurately characterized by the properties of methane (CH4), I'd use k = 1.32 per Crane TP410.

If not methane, what other component can accurately characterize your HC gas (Fuel gas)? If a single component cannot be used to characterize your HC gas (Fuel gas), then you'll need to use mixture calculations and the problem just got 10 to 100X harder.

[palaniappan]

If the properties of HC gas (Fuel gas) can be accurately characterized by the properties of methane (CH4), I'd use k = 1.32 per Crane TP410.

If not methane, what other component can accurately characterize your HC gas (Fuel gas)? If a single component cannot be used to characterize your HC gas (Fuel gas), then you'll need to use mixture calculations and the problem just got 10 to 100X harder.

Thank you Latexman,
The FG basically composes more of methane .

[JoeWong]

If your fuel gas can be properly characterized by EOS i.e PR, SRK, etc..., you may consider to use expander module in any simulator i.e HYSYS, PRO-II, etc by setting the isentropic efficiency being 100% with minor pressure drop...