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Chucho December 13, 2005 13:24

Inlets - Outles activation time
Is there any way to define the time at which the inlets and outlets should be opened? Is there any way of defining a kind of algorithm that rules the opening and closing activity of inlets? any help would help, tx

TB December 14, 2005 03:51

Re: Inlets - Outles activation time
why do you need that? Is it a transient simulation? Are you talking about "opening" boundary condition?

Chucho December 14, 2005 15:07

Re: Inlets - Outles activation time
Yes it is a transient simulation, i have inlet and oulet boundary conditions that works as fans or grilles, and what i need is to simulate the activation of this fans and the opening and closing of grilles. So is there any way to set this times?

Martin December 15, 2005 07:09

Re: Inlets - Outles activation time
that's pretty easy

If you want to set e.g. inletvelocity to 10 m/s at 5 s

you can write to the velocity at your inlet

step(5-Time/1[s])*0[m/s] + step(Time/1[s]-5)*10 [m/s]

step return 0 if the expression is <=0 and 1 if >0

you have to work without dimension within step, so you need Time/1[s].

bye martin

TB December 15, 2005 08:31

Re: Inlets - Outles activation time
Another method....Use profile boundary condition if you have some experimental data at inlet/outlet...

Chucho December 20, 2005 12:24

Re: Inlets - Outles activation time
When I look into the inlet properties the Profile Boundary option is disabled. How can I activate this option so I can enter experimental inlet data?

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