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Online Calculator: PipeFlow

PipeFlow

This calculator computes the properties of a liquid or a gas passing through a straight length of pipe.
Refer to the technical help page for the downloadable version of this calculator for additional assistance.

Units

You may use any units you like, but remember; you only get out what you enter.
We provide typical metric and Imperial units that you may (or may not) wish to use, but the output units provided are only valid if the input units (as displayed) are applied

Common Data:

This data applies to either (and both) of the calculation options below; Liquid and Gas.

Property: Data typical units
internal diameter (Ø): m (ft)
pipe length (L): m (ft)
surface roughness (ϵ): m (ft)
dynamic viscosity (μ): N.s/m² (ft-lbf.s/ft²)
gravitational acceleration (g): m/s² (ft/s²)


Liquid Flow Characteristics

This data applies only to calculations for [incompressible] liquid flow in a pipe.

Property: Data typical units
volume flow rate (Q): m³/s (ft³/s)
liquid density (ρ): kg/m³ (lb/ft³)

Property: Data typical units
average velocity (v): m³/s (ft³/s)
mass velocity (vm): kg/s (lb/s)
mass flow rate (G): kg/m²/s (lb/ft²/s)
pressure drop (δp): N/m² (Slug/ft²)


Gas Flow Characteristics

This data applies only to calculations for [compressible] gas flow in a pipe.

Property: Data typical units
inlet temperature (Ṯ): K (R)
inlet pressure (p₁): N/m² (slug/ft²)
outlet pressure (p₂): N/m² (slug/ft²)
relative atomic mass (RAM): N/m² (slug/ft²)
gas constant (Rᵢ): J/K/mol (ft-lbf/R/mol)

Property: Data typical units
average inlet density (ρ₁): kg/m³ (lb/ft³)
average inlet velocity (v₁): m/s (ft/s)
average outlet density (ρ₂): kg/m³ (lb/ft³)
average outlet velocity (v₂): m/s (ft/s)
mass velocity (vm): kg/s (lb/s)
mass flow rate (G): kg/m²/s (lb/ft²/s)
pressure drop (δp): N/m² (Slug/ft²)


Help

This PipeFlow calculator is accessible from anywhere in the website using the shortcut key; "Alt" + "p".

Liquid

In this calculator, it is assumed that the density of the liquid does not vary with pressure.
The pressure drop (δp) is due entirely to the friction from surface roughness (ϵ).

Gas

In this calculator, it is assumed that the density of the gas varies with pressure.
The pressure drop (δp) is due entirely to the friction from surface roughness (ϵ).

Downloadable Version

Full downloadable versions of this calculator is available from this website at; PipeFlow.

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