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3.2.4
Orifice/Pipe Diameter (inches)
The Orifice and Pipe Diameter fields allow the user to set the orifice and pipe
diameters. These are entered as floating point values, as measured in inches.
Changes to the pipe and orifice will cause significant changes to the flow rate
calculation. These rate changes can be viewed within the Current Values tab.
3.2.5
Auxiliary Factor (Faux)
The Auxiliary Factor (Faux) is a direct multiplier to flow rate. The rate changes can be
viewed within the Current Values tab.
3.2.6 Viscosity
Viscosity is a measure of fluid resistance to flow. The default value for viscosity (water)
is 0.8970, centipoise. Larger values will decrease flow rate. Smaller values will
increase flow rate.
3.2.7 Liquid
Type
The Liquid Type field allows the user to establish the liquid from a drop-down selection
field. The default is set to water.
If the user selects water as the liquid:
VCF = ( 999.840 + 6379830e-2 * tfc – 9.10603e-3 * tfc^2 + 1.00527e-4 * tfc^3 –
1.12671e-6 * tfc^4 + 6.59180e-9 * tfc^5 ) / 999.012;
Tfc = Flowing Temperature in Deg C.
If the selection is any of the other choices:
•
Unspecified
hydrocarbon
•
Crude
oils
•
Lubricating
oils
•
Gasoline/napthene
•
Jet
fuels/gasoline
•
Jet
fuels/kerosene/solvents
•
Diesels/heating and fuel oils
Then the VCF is calculated as follows:
If base gravity ( gb ) is > 0.6110
VCF = ( exp (-at * ( 1+ 0.8 * at );
At = deltaT * ( k0 / rhob^2 + k1 / rhob + k2);
Rhob = gb * 9999.012;
deltaT = tf – 60.0.
If ( 0.5 >= gb <= 0.611 )
VCF = 1 + (-1. 3.026e-2 * gb – 2.087e-2 * gb^2) * (-
2.840e-5 + 7.298e-5 * gb + 4.368e-5 * gb^2) * deltaT^2;
deltaT = tf – 60.0.