Propylene Density variation formula

[gkljayanth09]

Hi all,

I require the formula for density calculation of propylene which varies with temperature.

I have attempted to find out from Perry's Chemical Engg Handbook and got it as follows:

T-Temp in Kelvin
D- Density in kmol/m3

y=1+(1-T/C₃)^C₄
D = C₁/C₂^y

C₁= 1.4097
C₂=0.26465
C₃=365.57
C₄=0.295

Temperature Range - (87.89K-365.57K)
D at 87.89 = 18.143
D at 365.57 = 5.326

However, I have also got inputs from ASPEN's HYSYS 2008 software and the density values differ from that calculated with the formula .. there's difference of 14 kg/m3 for every value.

Can anybody please tell me the formula used for this calculation in APEN's HYSYS software?? Does anybody know ... Please share since this is an immediate need...

Thanks
Gokul