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Anonymous Poster

Equation For Orifice Plate Used

12/21/2007 1:42 AM

an orifice plate is used to measure gas flow through D/P cell. However, when I checked the configured equation for calculation toatiser value I found the equation configured as

comp flow = flow measure * sqr(comp-factor)

is the above equation is correctly configured.

the D/P cell meter is not conggured as SQR out put value.
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PWSlack
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#1

Re: Equation for orifice plate used

12/21/2007 6:00 AM

Differential pressure across an orifice is related to the flow by a square root function.

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vicini
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Join Date: Dec 2007
Posts: 588
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#2

Re: Equation For Orifice Plate Used

12/21/2007 11:32 AM

flow at std conditions = Dp^.5 * Press^.5 * Constant
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moon161
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Join Date: Dec 2005
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#3

Re: Equation For Orifice Plate Used

12/22/2007 12:21 AM

http://www.engineeringtoolbox.com/flow-coefficients-d_277.html


For more detail, check any fluids book or outline.
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Anonymous Poster
#4

Re: Equation For Orifice Plate Used

12/22/2007 12:45 AM

If you are using an orifice meter then

mass flow = constant * (P/T)^0.5 * (Diff pressure across orifice)^0.5

Take care of units used.
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agua_doc
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Location: Brecksville, OH
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#5
In reply to #4

Re: Equation For Orifice Plate Used

12/22/2007 2:10 PM

This is likely the best form of the equation to use for gas flows. By all means, verify the units in the equation.

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