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TESP Probe tip position

I am confused after reading TESP instructions on measurement.
It is stated" Static probes can be positioned into or away from airflow"
as long as holes in probes are perpendicular to airflow. Doesn't
this mean at 90Deg. from airflow?


  • STEVEusaPA
    STEVEusaPA Member Posts: 6,505
    It means the tips are pointing into the airflow or away from the airflow, not perpendicular, for regular, non pitot tubes.

    There was an error rendering this rich post.

  • aircooled81
    aircooled81 Member Posts: 205
    impact tube, you point into the air stream. Measuring the total air pressure (static and velocity). Parallel to the air.

    Static tube, it's perpendicular so you don't get velocity pressure. shove into side of duct but it cant be pointed toward or away from the flow.

    Pitot Tube, shaped like an "L"
    has a bit of both.
    tiny holes on side that will need to be perpendicular to the air flow, hole in the tip that points toward the airflow. when you plug it into the manometer, you get static pressure on one, you get total pressure on the other, your monometer shows you the difference between the two, we call that velocity pressure.