Date: Fri Mar 13 16:00:29 2009 Back to Contents ------------------------------------------------------------------------

Author: Gary Karshner

Subject: Re: Ruben's tube and propane

Post:

One small comment on Propane. It is heaver than air, unlike natural gas and
can collect in closed containers. Your tube is relatively small and this
should not be a problem. It is not as dramatic a difference as using sulfur
hexafloride for sound demonstrations.
Gary

At 11:58 AM 3/13/2009 -0400, you wrote:
>Hi Cliff,
>
>Dale is correct in his description of how well propane works in the
>Reuben's tube.
>I actually don't know how many places I've used the Reuben's tube. In
>bars, libraries, schools, gyms, and outside (!) demo shows, all with many
>different air currents and winds. If you are really worried about the air
>movement, just make a sturdy plexi shield to stand one foot back and
>around the sides of the tube. I made one when I first built the tube 20
>years ago, but I never actually need it so I don't use it. You sometimes
>need to finely regulate the gas flow yourself to make the wave forms
>visible, and this will vary as you go from low frequency to higher
>frequency standing waves, but you quickly learn how to do that when you
>are using it.
>
>McMaster-Carr is a great place to purchase a 5 lb propane tank to use in
>shows and in classrooms. Since so many schools are taking natural gas out
>of the classroom for insurance and safety purposes, having your own tank
>guarantees you can perform the demo where and whenever you want and need to.
>
>BTW, my tube has size .04" holes, or 1.016mm, spaced every half inch for
>72". This seems to work pretty well.
>
>Happy gas tubing,
>Dave/RU
>
>Dale E. Stille wrote:
>>Cliff,
>>
>>Zig and Dave Maiullo both run their tubes off propane using small 7 to 10
>>lb tanks with the standard pressure regulators. While you need different
>>orfices for things like stoves and water heaters for the different
>>gasses, I think you will find that the Rueben's tube is pretty forgiving
>>in this regard. So, you should be able to use it with either gas. I
>>would suggest getting the quick couplers for ease of attaching the tank
>>to the tube. ( They look and act the same as the couplers for high
>>pressure air hoses).
>>
>>Later,
>>Dale
>>
>>cbettis@unlserve.unl.edu wrote:
>>>One of our faculty wants to use my Ruben's tube as part of a road show
>>>to a high school. The school does not have a natural gas source for him
>>>so he wants to rent a propane tank to fuel the tube. I am concerned
>>>about: how well this will work, as I seem to remember that propane
>>>requires different sized orifices for flame jets than natural gas,
>>>safety (a tank of gas under pressure near an open flame in front of a
>>>large audience) and finally, in our lecture hall use, I find I have to
>>>turn off our air handlers to reduce air currents in the room so the
>>>flames are stable.
>>>
>>>So I was wondering if any of you had experience using the Ruben's tube
>>>on the road in such circumstances and had any advice for me to pass along.
>>>
>>>Cliff


From tap-l-owner@lists.ncsu.edu Fri Mar 13 16:00:29 2009

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