Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Aerospace Determination of Static Presssure on an Airfoil

  1. May 8, 2017 #1
    I'm working with data across an airfoil and need some help.

    We've got Kulite sensor data along 3 chord lengths of a certain NACA airfoil. The case is of an incompressible flow.

    I need to determine the coefficient of pressure at these sensor locations using total pressure measured and I, therefore, require the static pressure.

    What we have:

    Free stream static pressure
    Free stream total pressure
    Surface total pressure

    What I need:
    Surface static pressure

    Is this possible in any way? Thanks in advance.
  2. jcsd
  3. May 8, 2017 #2


    User Avatar
    Science Advisor
    Gold Member

    Wait, how do you have these Kulites mounted that they are measuring total pressure?
  4. May 8, 2017 #3
    They aren't? I'm just getting my hands into aerodynamics as I want to work on airfoil design and I got an internship working on this stuff. The thing is I read a few papers where they say the kulite sensors produced total pressure. I know for sure it's not static pressure as then there would have to be small holes on the airfoil to place the sensors inside? (or am I wrong).

    Do you think the Kulite sensors are measuring dynamic pressure which is 0.5*rho*v^2?
  5. May 8, 2017 #4


    User Avatar
    Science Advisor

    How do you mount the sensors?
    If they are mounted inside the airfoil, with the face flush with the surface of the airfoil so they do not disturb the flow, then they will read the static pressure against that surface.
    If you mount them facing the airflow they will read static + dynamic pressure.
  6. May 8, 2017 #5


    User Avatar
    Science Advisor
    Gold Member

    You can't directly measure dynamic pressure. That's the whole purpose of a Pitot-static tube. The important question is the one that @Baluncore asked. How are your probes mounted and oriented? That determines what they measure. Just calling them Kulites doesn't tell us much because Kulite, a brand name, makes hundreds of different sensor types that can be mounted many different ways and measure any sort of pressure.
  7. May 8, 2017 #6

    Dr Transport

    User Avatar
    Science Advisor
    Gold Member

    I have seen Kulites mounted on the backside where the skin has been machined to allow for static pressure measurement. I took a look at the Kulite website and they list static and dynamic pressure measurement for the models LQ-062, etc..... (FlightTest.pdf)
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted