C195 – AP09-600 – Flow Rate Calculation (Compensation Method)
Description
This calculation is used to calculate flow rate using a choice of algorithms commonly used by distributed control systems (DCS).
References
Honeywell – Advanced Process Manager Control Functions and Algorithms – AP09-600
Kelton calculation reference C195
FLOCALC calculation reference F052
KIMS calculation reference K195
Options
Primary Variable
- Mass
 
- Volume
 
- Energy
 
Select option based on desired flow parameter.
Input Method
- Linear Value
 
- % Linear
 
- % Square root
 
Select option based on whether the uncompensated flowrate is a linear or square rooted term.
Calculation Method
- A: Liquids
 
- B: Gasses and Vapours
 
- C: Gasses and Vapours with Specific Gravity
 
- D: Volumetric Flow of Gasses and Vapours
 
- E: Steam
 
Select option based on properties of the measured fluid.
Calculation
Flow compensation term
The flow compensation term is calculated by:

| Where | ||
|---|---|---|
| A, B, C, D, E | = | Refer to the calculation method for which the formula is employed | 
| G | = | Specific gravity | 
| RG | = | Design Specific gravity | 
| P | = | Pressure | 
| RP | = | Design Pressure | 
| T | = | Temperature | 
| RT | = | Design Temperature | 
| X | = | Steam Compressibility | 
| RX | = | Design Steam Compressibility | 
| Q | = | Steam Quality Factor | 
| RQ | = | Design Steam Quality Factor | 
Note: If input method is linear square root is not necessary.
Compensated flow rate
The flow rate is calculated by:
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| Where | ||
|---|---|---|
| C | = | Scale Factor | 
| C1 | = | 1st correction constant | 
| C2 | = | 2nd correction constant | 
| F | = | Uncompensated flow input | 
| COMPTERM | = | Flow compensation term |