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Old 01-19-2018, 12:50 PM   #32
Gunman
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Quote:
Originally Posted by gtengr View Post
I saw that model and I don't think it's detailed enough to check. I've already discarded the idea due to HVAC interference, but you realize the vent would be recessed under the back of the hood about 4 inches or so towards the front? And the CFD model doesn't consider the radiator airflow, which is the target of the venting. If airflow into the engine compartment is high enough, the firewall can create a high pressure zone too. I'm guessing that is what makes the hood dance at speed.
I haven't seen CFD, or tunnel testing, that did not show the cowl area as a high pressure zone. The turning of the air from a general horizontal, to more vertical direction, causes high pressure.

Granted, there are probably cases where something else is influencing it, and making it low pressure, but i have not seen it.
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