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Old 05-12-2021, 07:52 AM   #117 (permalink)
AeroMcAeroFace
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Quote:
Originally Posted by JulianEdgar View Post
Tuft testing will tell you airflow direction, but pressure testing will tell you airflow amount. Pressure testing will also tell you the results of small changes, eg I'd guess that adding a vertical forward projection to the outside edge of the opening would increase the pressure at the mouth of the duct.
adding a vertical forward projection to the outside edge of the opening This is a good idea, almost every air curtain I have seen has these forward projections.
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And unfortunately according to wikipedia "This type of flush inlet generally cannot achieve the larger ram pressures and flow volumes of an external design" Ram pressure is what you want in this case, so maybe a NACA duct isn't the ideal inlet.

increasing the inlet area, and trying to get as much airflow through the duct as possible. Inlet area greater than outlet area is generally of benefit too.

"It's great that you are doing stuff, but aiming a hair dryer at tufts on a stationary car tells you literally nothing at all," I disagree, but only slightly, the tuft direction will tell you where the air is aimed at, which is important in curtain design, if it is aimed wrong then it doesn't work regardless of the inlet. But I do agree that it is in no way representative of what happens when the car is driving.

Last edited by AeroMcAeroFace; 05-12-2021 at 07:56 AM.. Reason: addition of last paragraph
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