C261 – Gas Flowrate Conversion from Qm
Description
This converts a gas mass flow rate to observed, standard or normal volume flow rate as well as energy flow rate.
References
Kelton calculation reference C261
Options
Calculate
- Volume flow rate
- Standard volume flow rate
- Normal volume flow rate
- Energy flow rate
This allows selection of what type of flow rate mass flow rate is to be converted to.
Calorific Value
- Volume based
- Mass based
This option allows the user to enter either a volume or mass based calorific value when calculating energy flow rate.
Method
- Density
- Volume correction factor
This option allows the user to select whether to calculate a volumetric type flow rate using the equivalent gas density or by using a volume correction factor.
Volume Correction Factor
- User entered
- Calculated
This option allows the user to enter a volume correction factor or have it calculated using PTZ inputs.
Standard Density
- User entered
- Input as relative density
This option allows the user to select whether to enter standard density or enter a relative density, which will then be used to calculate standard density.
Calculation
Volume Flow Rate
The volume flow rate is calculated by:
If the density is calculated it is done by:
If the volume correction factor is calculated it is done by:
| Where | ||
|---|---|---|
| P | = | Pressure at line conditions |
| Pb | = | Pressure at base conditions |
| T | = | Temperature at line conditions |
| Tb | = | Temperature at base conditions |
| Z | = | Compressibility at line conditions |
| Zb | = | Compressibility at base conditions |
| ρ | = | Density at line conditions |
| ρb | = | Density at base conditions |
| Qm | = | Mass flow rate |
Energy Flow Rate
The energy flow rate is calculated by:
If volumetric calorific value is applied:
If mass based calorific value is applied:
