What is the size of a wing generally for testing in a standard wind tunnel?
It depends on the wind tunnel facility.
Call them and ask, though you are not going to afford to have any wind tunnel work done. It's going to run you at least 60k.
There is no such thing as a "standard wind tunnel". They come in all sizes, from a few inches to life-sized.
I know of some high schools that have small wind tunnels. I guess the question remains what you are trying to test. Is it high speed or low speed? Are you looking at an entire model or just a cross section of an airfoil?
I am just trying to test a cross section of an airfoil, at low speeds.
Are you familiar with the topic of dimensionless groups and similitude? Do a search on Buckingham Pi Theorem. This allows you to scale your model for the equipment you have (in most cases). Take a look through the following links:
Thank you very much Mr. Garvin.
I hope it helped. If not, keep asking questions.
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