HydraulicInertia

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HydraulicInertia

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Iconic Diagrams\Hydraulics\Components

Use

Domains: Continuous. Size: 1-D. Kind: Iconic Diagrams (Hydraulics).

Description

When a fluid flow changes speed, a force is needed to accelerate the fluid. This force is equal to the acceleration multiplied by the mass of the fluid.

 

F = m * dv/dt

 

HydraulicInertia

The fluid mass is equal to the pipe area multiplied by the pipe length and the fluid density:

 

m = A * l * rho

 

The force will result in a pressure differential:

 

F = A * dp = A * (pa.p - pb.p)

 

We can rewrite the formulas as

 

dp = rho * l * dv/dt

 

and by introducing the fluid flow phi:

 

v = phi/A

 

we get the formula for an hydraulic inertia:

 

dp = (rho * l / A) * d phi/dt

Interface

Ports

Description

pa, pb

Both terminals of the hydraulic inertia.

Causality

 

fixed pressure out pa

fixed pressure out pb

 

Parameters

 

rho

d

l

Mass density of the fluid [kg/m3].

pipe diameter [m]

pipe length [m]