Very Confused Static Pressure?

Click For Summary
SUMMARY

This discussion focuses on calculating thrust from a propeller using propeller velocity and Bernoulli's equation. The user, Andy, outlines the formula for propeller velocity as the product of pitch and RPM. He attempts to apply Bernoulli's equation, specifically pt0 = p0 + 0.5 * r * pv^2, but struggles with determining the static pressure (p0). A key insight is that in an open airflow situation, static pressure is effectively zero.

PREREQUISITES
  • Understanding of propeller mechanics, including pitch and RPM.
  • Familiarity with Bernoulli's equation and its application in fluid dynamics.
  • Basic knowledge of pressure concepts, particularly static pressure.
  • Mathematical skills to manipulate equations and perform calculations.
NEXT STEPS
  • Research the application of Bernoulli's equation in open airflow scenarios.
  • Study the relationship between propeller pitch, RPM, and thrust generation.
  • Learn about static pressure measurement techniques in fluid dynamics.
  • Explore advanced topics in fluid mechanics related to propeller efficiency.
USEFUL FOR

Aerospace engineers, mechanical engineers, and hobbyists involved in propeller design and performance analysis will benefit from this discussion.

Gibbon
Messages
22
Reaction score
0
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
 
Physics news on Phys.org
In an open airflow situation (no ducting), there is no static pressure.
 

Similar threads

Graduate Does Fluid Dynamics Explain Pressure Gradients in a Frictionless Tube?
  • · Replies 48 ·
2
Replies
48
Views
6K
High School What actually is static pressure?
  • · Replies 11 ·
Replies
11
Views
3K
Clarifying the Definition Total/Stagnation Pressure (p₀) in Bernoulli'
  • · Replies 2 ·
Replies
2
Views
1K
Graduate Fluid mechanics in a water container, reference from Feynman
  • · Replies 13 ·
Replies
13
Views
3K
Graduate Validity of rocket pressure thrust term
  • · Replies 11 ·
Replies
11
Views
5K
Static pressure in a water pipe system
  • · Replies 11 ·
Replies
11
Views
4K
Graduate Why does the pressure of a fluid in motion change?
  • · Replies 3 ·
Replies
3
Views
3K
Work done on container receiving gas from high pressure container
  • · Replies 1 ·
Replies
1
Views
2K
Graduate Confused about use of external vs internal pressure in thermodynamics
  • · Replies 13 ·
Replies
13
Views
3K
How Do You Calculate Static Pressure Drop in a Laminar Flow Channel?
  • · Replies 3 ·
Replies
3
Views
2K