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gas mixing through a T joints

gas mixing through a T joints

gas mixing through a T joints

(OP)
Hellow,
Looks like here is a good place to presnt my silly question. Thank you in advance.
I'm currently "hybriding" two gas flow with a T joint. Both in small flow rate, so the diameter of the  pipes is about half centimeter.
the two inlets are managed with separate mass flow controllers. which have been setting to following values:
        in 1        in 2
case 1: 150sccm/m  50sccm/m
case 2: 100sccm/m  100sccm/m
case 3: 50sccm/m   150sccm/m
                ]    [       
                ]in2[
                ]    [
-------------]    [-----------
inlet 1                outlet
-----------------------------

My question is would any of the inlet flows being surpressed by another one, if we could assume the mass flow controller is constantly outputing the presetted value. especially when the inlet2 is 150sccm/m


regards

RE: gas mixing through a T joints

Depends on the injection pressures of each stream.

Let your acquaintances be many, but your advisors one in a thousand'  ...  Book of Ecclesiasticus

RE: gas mixing through a T joints

(OP)
They pressure in those inlet pipes is able to build up as the flow controller output rather stable. So I hope the pressure at the interface will eventually equal. And a steady mixed output can be expected.

RE: gas mixing through a T joints

If that's the case, you should have no problems.

Let your acquaintances be many, but your advisors one in a thousand'  ...  Book of Ecclesiasticus

RE: gas mixing through a T joints

Despite your expectation about steady inputs as well as steady output/consumption, I can hardly imagine how can you avoid troubles in transition periods with whatever consequences: starting up two injection flows; turning consumption on/off and similar.

Believe buffer should be necessary to overcome that. Outlet pipe can serve similar purpose, if having sufficient lenght/diameter.

Did you consider installation of turbulator that would speed up and improve mixing?

RE: gas mixing through a T joints

Yes.  Maybe you will have trouble for a whole 1 ms.

Let your acquaintances be many, but your advisors one in a thousand'  ...  Book of Ecclesiasticus

RE: gas mixing through a T joints

(OP)
Thank you BigInch and Drazen,
I run the flow for hours, so some seconds is not a problem. As far as a stable flow will be obained in the end.

I forget to tell the pipes is connected to a tiny chamber which has a exhaust. So the consumption is always there.
regarding the buffer, I think it's like a chamber the two inputs can go in and has a outlet. I guess it can lighten the "conflict" of two flows, so they can flow in the defined rate even at transition periods.

If anyone agrees what I said above. I shall do it. By the way, where can I buy such a chamber/bottle.  

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