Very Confused Static Pressure?

AI Thread Summary
To calculate thrust from a propeller, one must first determine the propeller velocity using the formula: prop velocity (pv) = pitch * rpm. This velocity is then used in Bernoulli's equation to find thrust, which involves calculating pressure with the equation pt0 = p0 + 0.5 * r * pv^2. The challenge arises with understanding static pressure (p0), which is crucial for the calculation. In open airflow situations without ducting, static pressure is effectively zero, complicating the thrust calculation. Understanding these concepts is essential for accurate thrust estimation.
Gibbon
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Hi, I am trying to calculate as best but simply as i can the (approx) thrust from a propeller..

and my research shows i have to calculate:

prop velocity(pv) = pitch * rpm

with pv i can then use Bernoulli's equation to calulate the pressure and multiply it by the propeller surface area to give me thrust.

So ... pt0 = p0 + .5 * r * pv ^2

that equation should give me thrust.. But. p0 is apparently "Static Pressure".. and i cannot for the life of me work out how to calculate static pressure.

Hope you can help, my maths isn't all upto scratch so be kind! :)

Thanks
Andy
 
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In an open airflow situation (no ducting), there is no static pressure.
 

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