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Old 23rd February 2011 | 11:58
  #70 (permalink)  
Graviman
 
Joined: Nov 2004
Posts: 1,334
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From: Cambridgeshire, UK
Helisphere, what you have to remember is that total pressure (static + dynamic) only stays constant along a streamline. So in an ideal world the pitot-static ports both operate on the same streamline.

In a rotor the inflow "streamlines" gets muddled up as each blade passes, so if you are only looking at the larger picture then it appears that there is a step increase in total pressure across the rotor "disk". Since engineers (like myself) are trying to produce a useable model then this is all nicely wrapped up in the name "disk actuator theory". Both above and below the rotor, along each streamline, Bernoulli applies as normal...

Last edited by Graviman; 24th February 2011 at 11:48.
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