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Airflow velocity through hole on an aircraft

Airflow velocity through hole on an aircraft

Airflow velocity through hole on an aircraft


I'd like to design an air particle pollution sensing interface prototype, mounted on an aircraft. If the aircraft's velocity, the inlet and outlet diameter of the hole is known, how can I calculate the airflow's velocity through the hole? Thanks in advance.


RE: Airflow velocity through hole on an aircraft

I am fairly confident from the information given that the magnitude of the airflow velocity will be at least zero and probably not greater than the local speed of sound.

Unfortunately I can't predict whether the velocity will even be negative or positive, never mind what the magnitude actually is.


Greg Locock

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RE: Airflow velocity through hole on an aircraft

That narrows it down to a ballpark Greg (the Universe). Only more detailed info can make it more precise.

RE: Airflow velocity through hole on an aircraft

research nozzle design, flow through a tube.

is the tube going to be straight (like a pipe) or convergent/divergent ?

is the opening going to "choke", or will be allow free steam velocities to develop ?

how fast is the plane going ? sub-sonic ? super-sonic ?

is the opening located away from the plane (in free stream conditions), or close to it (so it is affected by the airflow around the plane) ?

Quando Omni Flunkus Moritati

RE: Airflow velocity through hole on an aircraft

Thank you for the answers.

What I'd like to do is basically a jet pump where both motive and secondary flow would be air. The device would be mounted on an airplane where the secondary flow inlet is facing to the ground. I just need something to understand the initial calculations, especially for the design of the suction chamber to achieve a low volume flow in the secondary section. This air would be absorbed in water and high air velocity would draw out the water from its chamber. I'm well aware that several experiments will be needed.

RE: Airflow velocity through hole on an aircraft

I've heard talk about an experimental device called a "venturi".
Probably another silly device named after its inventor that will never find a practical use.
But you could try it.

Yes, we're teasing you. It's not nice, but you are asking "student" questions.

This is chapter 1 in any fluid dynamics / aerodynamics textbook.
A small effort at research would turn up all the answers to your questions.


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