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Old 16th September 2014, 06:22 PM   #1
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Default Transmission line 'flow simulation'

So I was bored and wanted to know the use of corner pieces in a transmission line box.
I already had a model in Solidworks so decided to do a flow simulation here.
I've attached a image of what the program calculated.
One is with corner pieces, and one without.
So can I say the corner pieces are sort of useless for the airflow?
Or is there an other advantage why everyone should use them?
Attached Images
File Type: png TL + corners.png (251.4 KB, 214 views)
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Old 16th September 2014, 06:48 PM   #2
tb46 is offline tb46  United States
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Hi Michelp89,

Very neat simulations.

At low frequencies the corner braces only serve to stiffen the box. (They also reduce the volume.)

We have been talking about intentionally placing constrictions in ducts, wonder what that would do in the flow simulation?

New sub design? Constricted Transflex, simple build (series tuned 6th order)

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File Type: jpg TL_constriction.jpg (38.8 KB, 202 views)
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Old 16th September 2014, 07:00 PM   #3
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Here you go!
(same parameters used as the first simulations)
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File Type: png Tl constriction.png (135.1 KB, 199 views)
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Old 16th September 2014, 07:06 PM   #4
tb46 is offline tb46  United States
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Hi Michelp89,

That was fast. Can you tighten the constriction to maybe half of what it is now? What would happen if there is an opening (terminus/port) @ the end where you are showing the dark blue swirl, can that be done? And what does it all mean? :-)

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Old 16th September 2014, 07:26 PM   #5
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On the top is the woofer position. So that is the start point of the air movement. At the right bottom is the TL opening. So that is where al the air is going. Dark blue is low velocity, red is high velocity. Don't look at the numbers, i used random numbers at the parameters, the airflow will we about the same I think if I use a high or low volume of air.
I think I can try the stuff you say
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Old 16th September 2014, 07:36 PM   #6
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Here is the contriction, but with a smaller surface
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File Type: png Tl constriction half surface.png (138.3 KB, 185 views)
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Old 16th September 2014, 07:40 PM   #7
tb46 is offline tb46  United States
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Hi Michelp89,

There seem to be large areas that are not involved in the flow regime. I'm not sure what that means, maybe simulation in AkAbak, and taking those inactive areas out may give an idea. This is definitely interesting.

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Old 16th September 2014, 07:45 PM   #8
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I also noticed that, but don't know what to think of that.
This is just simple simulation software. The results could be different with some expensive simulation software

edit: this image is the same as the last, but with both sides open
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File Type: png Tl constriction half surface both sides open.png (110.1 KB, 177 views)
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Old 16th September 2014, 07:49 PM   #9
tb46 is offline tb46  United States
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Hi,

It's a lot more complex simulation software than what I have access to. Thank you very much. The question I have is, how does steady flow compare to pulsating pressure progapation? Or is that already part of the simulation?

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Old 16th September 2014, 07:56 PM   #10
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This is just one push of air. I don't think I can simulate pulsating pressures. You mean a simulation where the cone moves up and down at a certain frequency, right?
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