Hello all,

Could anybody Explain how to guess the momentum source value in a tube please.

I'm simulaing the flow in an open end tube which has the momentum source inside. I expect 0.1 m/s velocity at the position adding the momentum . I know the cross section area of the tube and the volume of the 3D region of the source and the unit of the momentum source is kg/m^-2s^-2. Does any body have an idea how to guess it ( equation and method )

I'm looking forward to hear the kindly help soon, @T_T@

Thank you in advance.

Jackie

Hi Jackie,

The momentum source basically specifies a pressure gradient, however you can modify modify it to get a specific speed.

The following settings will do the trick:

MOMENTUM SOURCE:

Momentum Source X Component = -C*(u-uspec)

Momentum Source Y Component = -C*(v-vspec)

Momentum Source Z Component = -C*(w-wspec)

Momentum Source Coefficient = -C END

where C is a very large number and uspec, vspec, and wspec, are the specified velocities.

Regards, Robin

How could I know C value Robin.

Jackie,

The actual value does not matter, it just has to be a big number.

Robin

Thank you very much Robin.

Jackie