Where does this come from, and can I check it?

Small models are tested at higher speed and pressure so the airflow behaves like the full size aircraft. The figure is taken from NASA Glenn Research Center, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.

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Yes. It sits on the Technology shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.

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The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.

Mondo Knows Facts

Wind tunnel models must match the right numbers

Small models are tested at higher speed and pressure so the airflow behaves like the full size aircraft Airflow around a body depends on the Reynolds number, a ratio of inertial to viscous forces, and a small model at low speed has a far lower one than the real aircraft. Tunnels compensate with pressurised or refrigerated air, or with higher speeds, so the number matches. Results are then corrected for the tunnel walls, which squeeze the flow in ways open air does not. It sits in Mondo's technology collection, one of 200 facts that each trace back to the reference below.

Where this comes from

NASA Glenn Research Center

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Tags: aviation, testing, aerodynamics

Wind tunnel models must match the right numbers: the short answers

Where does this come from, and can I check it?: Small models are tested at higher speed and pressure so the airflow behaves like the full size aircraft. The figure is taken from NASA Glenn Research Center, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
Is this really a technology fact?: Yes. It sits on the Technology shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
What else can I read about it?: The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.