Spirit flow-x, Справочник по функциям

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Flow-X─ Function Reference
4-63
Flow-X General functions - fxAGA3_C
Pressure correction

The relation between the pressure at the upstream tapping p
1
and the pressure at the
downstream tapping (p
2
) is as following:
1000
1 2
units
K p
p p
 
 

The relation between the pressure at the upstream tapping and the downstream tapping is
as following:
LOSS
p p p
 
1 3
 
 
units LOSS
K p p
  
 
 

2
2
1
1
 
 
 
4
1
1




 
E
E C
Where:
p
1
Pressure at upstream tapping psia
p
2
Pressure at downstream tapping psia
p
3
Fully recovered downstream pressure psia

p Differential pressure inH20 @
60°F
p
LOSS
Pressure loss over the meter psi
C Discharge coefficient as calculated by the standard -
α Flow coefficient -
β Diameter ratio at the upstream pressure and temperature -
E Velocity of approach factor -
K
units
Unit conversion factor to convert a value expressed in 'inH2O @60°F' to the
corresponding expressed in 'psi' (conversion as specified in section 'Unit
Types') -
Temperature correction

When input 'Temperature correction' is set to 1, then an isentropic expansion based on the
isentropic coefficient is applied:
 
67 . 459 67 . 459
1
1
2
2 1







  



p
p
t t