[Romarius]

Hey guys,

I'm starting a project on a pipe gas flow between two tanks with different pressures. To set the initial condition on pressure, I had to create a field function which defined the pressure amplitude in function of x axis position.

So here's the problem:

P = 1000 Pa, 0<x<1 m
P = 200 Pa, 1<x<2 m

To make that, I was choosing a scalar field function and as definition I wrote:

($Position[1] < 1) ? 1000, 200

But that doesn't work

Does anybody have an idea whats wrong with my function?

Thanks,
Jishen

[azt]

Try using $$Position[1] or $$Centroid[1]

$ refers to a scalar, $$ for a vector

Position refers to geometry and centroid to the mesh

azt

[ping]

there is another mistake in your equation since the command should be a colan

and a slight correction to what the location fields refer to

$$Position gives vertex location and for a cell is the average of the positions of the vertices of the cell
$$Centroid gives the cell or face centroid location

[JBeilke]

$$Position[1] gives the y-Value. You have to use $$Position[0] instead.

[Romarius]

It works, thank all of you!

=)