Natural gas calculator

calculation of natural gas pressure drop or flow rate

online since 2006

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Read all about available deployments. In any way of utilizing calculator, Internet connection is required, for authentication at least.

Available in download version

save/open multiple results
export to word and excel
print results
custom fluid properties
K factor for fittings, resistance coefficient
select between gauge and absolute pressure
compressible isothermal flow
dry air isothermal flow
gas offtake flow
natural gas flow


When is this calculator suitable?

You can use the calculator for flow rate and pressure drop calculation in a constant diameter, natural gas pipeline. The calculator assumes that the flow is compressible. Therefore you can use the calculator for pressure drop and flow rate in medium to high-pressure gas lines.

What are the calculator restrictions?

Gauge pressure must be higher than 1 bar and lower than 100 bar. The pipeline should be longer than 1m.

How is the calculation executed?

The Calculator uses Renouard equation for calculation. It assumes that the temperature of the natural gas flow in long pipelines is constant. The temperature of the natural gas in gas lines is constant because natural gas recovers the drop in temperature through the heat exchange with the surrounding soil.

In the flow rate calculation scenario, the calculator calculates and shows the flow rate at standard conditions.

If you are calculating pressure drop, then you should enter flow rate at standard conditions in the calculator.

Standard conditions are:

- p = 101325 Pa and
- t = 15 0C.

The calculator also presents actual flow mean velocity in the pipeline for specified pipe diameter.

When is this calculator not relevant?

This calculator is not suitable for low-pressure gas installations. The calculator can't be used to calculate pressure losses due to resistance in valves and pipe fittings and pressure changes due to height change.

Need a helping hand?


If you need a quick calculation, but you are not still familiar how to use the calculator, you can order calculation service from the calculator developer.

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