Thermo Scientific Sarasota SG901, Руководство пользователя

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Configuration Considerations when Using Sarasota CM515
Critical Temperature and Critical Pressure
F-4
Sarasota SG901 User Guide Thermo Fisher Scientific
This allows the user to fit the basic constituents CT and CP values to a
quadratic equation and then enter constants Critical Pressure Base, A, and
B or Critical Temperature Base, A, and B. An example of this is shown
below.
Table F–3.
ATMOS K Bar
SG Cp Ct CP CT Calc CP Calc
H2 0.069046 12.8 33.2 12.9696 36.41803155 16.30964
CH4 0.552364 45.34 190.6 45.94076 184.7276523 35.44646
C2H6 1.035683 48.2 305.4 48.83865 304.4954727 46.3046
C3H8 1.519001 41.9 396.8 42.45518 395.7214929 48.88407
C4H10 2.00232 37.5 452.2 37.99688 458.4057127 43.18487
C5H12 2.485639 33.3 496.6 33.74123 492.5481323 29.20699
The above table shows the CP and CT for typical gas constituents. The
data was fitted to the curves in the equations below, and the CP Calc in bar
and CT Calc in K are shown in the calc results.
Table F–4.
Data assuming curve fit gives ax^2 + bx +c
CT is in K and CP is in bar A.
Standard Form Coefficients a b c
Sarasota CM515 Coefficients B A Base
CT calc -61.092 344.82 12.901
CP calc -17.72 50.606 12.9
Acentric factor 0.0775 Isentropic exp 1.3
CT Entered -4.73545 26.72816061 12.901
CP Entered -1.37364 3.922945736 12.9
Note that the coefficients a, b, and c relate to the form A * SG^2 + B * SG
+ C. CT Entered and CP Entered relate the constants A, B, and C to the
Entered CT or CP constants for the Sarasota CM515.
Note that A = b/base and B = A/base in each case.