Spirit flow-x, Справочник по функциям

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Flow-X─ Function Reference
Flow-X General functions - fxASTM_D1550_RD60
F Compressibility factor
The output value will be either rounded
or not depending input 'API 11.2.2
rounding' 1/psi F 0
CTL Volume correction factor for
temperature. - CTL 1
CPL Volume correction factor for pressure
Value will be rounded according to input
'API 11.2.2 rounding' - CPL 1
ASTM D1550
calculation
out of range With respect to ASTM D1550 table 1 the
input values are:
0: In Range
1: Out of Range - ASTM
_OOR 0
API 11.2.2
calculation
out of range With respect to API 11.2.2 the
conditions of density, temperature and
pressure are:
0: In Range
1: Out of Range API_O
OR
Calculations
The function performs the following iterative algorithm to calculate the relative density at 60
°
F and 0
psig. No rounding is applied
1. At the start of the iteration the relative density at [60

F, 0 psig] is set equal to the
observed relative density and the CPL value is set to 1.
2. The relative density corrected for pressure is calculated by dividing the observed
relative density by the CPL value.
3. The CTL value and the relative density at [60

F, equilibrium pressure] is calculated from
the relative density corrected for pressure and the observed temperature according to
ASTM D1550 Table 1
4. The compressibility factor F is calculated according to API MPMS 11.2.2 from the
relative density at [60

F, equilibrium pressure] and the 'Observed temperature'.
Depending on setting ‘API 11.2.2. rounding’ the rounding and truncation rules of API
11.2.2. are applied for this step.
5. The CPL value is calculated from the calculated compressibility factor and the 'Observed
pressure' input value.
6. The new value for relative density at [60

F, 0 psig] is calculated by dividing the observed
density by the CTL and CPL values.
7. Steps 2 through 6 are repeated until the absolute difference between two consecutive
relative density values is less than the convergence limit of 1e-8.
When no convergence is achieved in 20 iterations then the status output is set to ‘No
convergence’ and the relative density output is set to 0.