C170 – Instromet – Ultrasonic Meter Flowrate
Description
This calculates the volume flow rate corrected for the temperature and pressure of the spool piece when using an Instromet ultrasonic meter.
References
Temperature and pressure correction for ultrasonic gas flow meters, Geeuwke de Boer & Jan G Drenthen: Instromet International N.V.
Kelton calculation reference C170
FLOCALC Calculation reference F039
KIMS Calculation reference K176
Kelton calculation C244 – Calibration Correction
Options
Spool Correction Factor
- User entered
Select this option to enter a single multiplier for the correction factor – if no correction is made set this value to 1
- Calculated
Select this option to calculate the correction factors using the manufacturers equations
Calibration Correction
- None
Select this option if you do not wish to correct the flow rate for the calibration curve
- Before Spool Correction
Select this option if you wish to correct the flow rate based on the calibration data before applying the correction for spool temperature and pressure
- After Spool Correction
Select this option if you wish to correct the flow rate based on the calibration data after applying the correction for spool temperature and pressure
The correction is carried out as per C244.
Spool Piece
- Flanged
Select this option for flanged spool piece meters
- Welded
Select this option for welded spool piece meters
Calculate for
The calculated flow rate can be expressed in:
- Observed volume flow rate
- Mass flow rate
- Standard volume flow rate
- Normal volume flow rate
- Energy flow rate
Calculations
All calculations are performed in SI Units unless otherwise stated
If the flanged spool piece option is chosen
If the welded spool piece option is chosen
| Where | ||
| Q | = | The displayed volume flow rate |
| α | = | The temperature coefficient for the spool |
| ta | = | The spool temperature |
| tr | = | The reference spool temperature |
| D | = | The internal meter diameter |
| d | = | The meter wall thickness |
| E | = | Young’s modulus of elasticity |
| Pa | = | The spool pressure |
| Pr | = | The reference spool pressure |