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Gannet
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Vena Contracta

10/07/2008 6:29 PM

Does the Vena Contracta of a sharp edge orifice that discharges air directly to the atmosphere varies from that when it discharges into pipe that is open to the atmosphere?
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PWSlack
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#1

Re: Vena Contracta

10/08/2008 4:29 AM

Er, run that question again, please.

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charlie_r
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#2

Re: Vena Contracta

10/08/2008 5:56 AM

I see on wikipedia that there is no mention of this phenomenon differing. They even give a typical number for use in calculations.

This google search shows 304,000 results.......

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Gannet
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#3

Re: Vena Contracta

10/08/2008 12:26 PM

Figure 3.25 from http://www.aeromech.usyd.edu.au/aero/cvanalysis/node3.shtml#node43 - sorry, link no longer available

I am curious if an orifice flowmeter that discharges directly to atmosphere would have the same vena contracta diameter as one discharging into a short length pipe that is opened to atmosphere. All the calculations I have found are for orifices that discharge directly into a pipe that is the same diameter as the inlet pipe.
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