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Old 20th Mar 2009, 21:21
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Flex_Thrust
 
Join Date: Jun 2005
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Knife Edge Oriface in VSI Metering Unit

Hi,
I am hung up on the k.e.o. part of the metering unit. I understand that it compensates for laminar flow in the capilliary allowing the vsi to correctly show altitude change at all densities/temperatures, and it somehow uses turbulent flow to do this.
My difficulty is with the turbulent flow part - I see the oriface as simply another opening in the case that would allow more airflow.
Can anyone give me an explanation?!

Last edited by Flex_Thrust; 20th Mar 2009 at 23:18.
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