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Incorporated, a worldwide network of science museums and related institutions.
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Hi Peter et al,

You can use a simple device based upon a Mariotte Bottle or flask: http://www.geotech.cv.titech.ac.jp/IJPMG/papers/ijpmg_vol2_no1_3.pdf

We used such a system several times for metering constant volumes and maintaining constant pressures in exhibits.
C
On Aug 19, 2010, at 8:07 AM, Peter Ford wrote:

> ISEN-ASTC-L is a service of the Association of Science-Technology Centers
> Incorporated, a worldwide network of science museums and related institutions.
> *****************************************************************************
> 
> Hi all,
> 
> Here’s the technical dilemma that I’m trying to solve.
> 
> I want to drain a tank of water, from the bottom, at the same rate regardless of how much water is in the tank. So whether there is 5” or 20” of water in the tank it will drain at ½ gal a minute (values are somewhat arbitrary for this example).
> 
> So how can I do this? I’ve tested Pressure-Compensating Orifice from McMaster but that didn’t work (I think the pressure is to low for them to work). I have seen devices that automatically regulate but they are for larger industrial systems (and cost a lot), or they are for higher pressure systems.
> 
> For more specificity it’s a 11” diameter tank and I’m draining through a 1” valve. The water height varies between 4” to 30”
> 
> Any solutions, or ideas, would be appreciated.
> 
> Thank you in advance.
> -Peter
> 
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Charles Carlson
Senior Scientist
exploratorium
3601 Lyon St.
San Francisco, CA 94123
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Tel:   415-561-0319
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For information about the Association of Science-Technology Centers and the Informal Science Education Network please visit www.astc.org.

Check out the latest case studies and reviews on ExhibitFiles at www.exhibitfiles.org.

The ISEN-ASTC-L email list is powered by LISTSERVR software from L-Soft. To learn more, visit
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