Date: Mon Oct 26 10:21:35 2009 ** **Back to Contents ** ------------------------------------------------------------------------ **

Author: Lally, Sean

Subject: Speaking of wind tunnels....


Can any of you share your secrets for building basic wind tunnels (low budget)?

-----Original Message-----
From: [] On Behalf Of Michael Timmins
Sent: Sunday, October 25, 2009 7:57 AM
Subject: Re: [tap-l] Fog Machines

We've done a similar thing here with an old wind tunnel. We used a 5
gallon water jug as the container filled with fog.
Even though our tunnel had a fan at the back end, I have to force air
into the jug to get the fog entering the tunnel at the same speed as
the incoming air. It works pretty well but it needs to be cleaned
from time to time as condensation forms from the fog liquid.

Mike Timmins

On Oct 24, 2009, at 1:57 PM, Paul Doherty wrote:

> We made a wind tunnel with mist lines at the Exploratorium,
> We did a wind tunnel where the fan was downstream air entered
> through a honeycomb structure.
> Then flowed around an object on its way to the fan.
> We inserted a few straws through the honeycomb attached to a fog
> filled chamber.
> This resulted in a linear array of mist trails that nicely showed
> the arrangement of streamlines.
> We even spun a baseball in the stream and showed the deflection of
> the airstreams by the rotating ball.
> Paul D
> On Oct 24, 2009, at 8:42 AM, David Maiullo wrote:
>> Hi Urs,
>> I've tried to illustrate the path of the blower air around a beach
>> ball using fog. The problem in using the fogger, at least mine,
>> is that it's tough to regulate the fog from the device so you
>> quickly get too much and it blocks the effect you are trying to
>> illustrate, instead of illuminating it.
>> But I think this problem could and should be rectified if you
>> where to make a pvc pipe, with holes placed strategically on it,
>> plumbing contraption attached to the fogger output which you could
>> place in the right location, giving you individual fog streams. I
>> need to try that........anyone else try this?
>> Happy fogging from here in the US of A!
>> Dave/RU
>> Urs Lauterburg wrote:
>>> Hey Dave,
>>> Maybe the combination of a fogger and a bladeless fan opens a
>>> possibility for some interesting aerodynamics dynamics stuff.
>>> Maybe it's possible to make a continuos fog beam which could flow
>>> around differently shaped objects.
>>> Has anybody tried this out yet?
>>> Regards
>>> Urs
>>> Urs Lauterburg
>>> Physics demonstrator
>>> Physikalisches Institut
>>> University of Bern
>>> Switzerland
>>>> Hi Tappers,
>>>> Just a reminder to everyone that now is the time to look for and
>>>> purchase fog machines. It seems, with the growth of Halloween
>>>> and Halloween parties, they are available at more places now
>>>> than ever before.
>>>> I know that Guitar Centers are selling a 400 watt fogger for
>>>> less than $20, though I can't vouch for quality. I think this
>>>> price is not available on line from them.
>>>> i1155703.gc
>>>> But Drug and General stores frequently have them now, too.
>>>> Perhaps even Walmart(?).
>>>> Happy fogging,
>>>> Dave/RU

From Mon Oct 26 10:21:35 2009