Spirit flow-x Function Reference page 114

Flow-X─ Function Reference
4-114
Flow-X General functions - fxAPI_RD60F_1980
K1
K2
Alpha
F
Product
CTL calc out of
range
CPL calc out of
range
Calculations
The calculations depend on the conversion method.
Conversion method 1: from observed to standard conditions.
The function performs the following iterative algorithm to calculate the relative density at standard
conditions:
Actual value of constant K1 used
for CTL calculation
Actual value of constant K2 used
for CTL calculation
Thermal expansion factor
Compressibility factor
When input 'Product' is 'B - Auto
select', then the output is set to
the actual selected product of
table 23B/24B (enumerative
value as defined for input
'Product'), else the output is set
equal to input 'Product'.
With respect to the standard
used for the calculation of CTL
the combination of input values
is:
0: In Range
1: Out of Range
With respect to the standard
used for the calculation of CPL
the combination of input values
is:
0: In Range
1: Out of Range
1. First the inputs are rounded in accordance with the API2540 standard, provided
that API2540 rounding is enabled.
2. The observed density [kg/m3] is calculated from the observed relative density
3. The hydrometer correction on the observed density is applied, provided that this
correction is enabled
4. At the start of the iteration the initial value for density and relative density at [60
F, equilibrium pressure] is set to respectively the observed density and the
observed relative density. The initial CPL value is set to 1.
5. When the type of product is set to 'B – Auto select' (automatic selection of the
refined product range) the K0, K1 and K2 factors are determined based on the
relative density at [60 F, equilibrium pressure]. The Transition area is only taken
nd
in consideration in the 2
The Alpha factor is calculated according from the density at [60 C, equilibrium
6.
pressure] and the K0, K1 and K2 factor. If API2540 rounding is enabled, then the
intermediate results are rounded or truncated as specified API-2540 Table 23.
7. The CTL value is calculated according to API-2540 Table 23 from the Alpha factor
and the differential temperature (= observed temperature – 60°F). If API2540
rounding is enabled, then the intermediate results are rounded or truncated as
specified API-2540 Table 23.
8. Depending on the type of API2540 rounding the calculated CTL value is rounded
to 6 decimal places or not rounded at all.
The density at [60 F, equilibrium pressure] is calculated by dividing the observed
9.
density by the new CTL value and the CPL value from the previous iteration.
- K1
- K2
1/°F ALPHA
- F
- PRDCUR
CTLOOR
CPLOOR
iteration loop, as specified in the standard.
0
0
0
0
0
0
0