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Old 07-21-2018, 12:54 PM   #11 (permalink)
aerohead
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stepped-hull

Quote:
Originally Posted by gumby79 View Post
If the louvers were v-shaped instead of straight then they may act like a step hull of a boat, reducing wetted area intern drag.
Making channels for the higher pressure on the sides to merge with the lower pressure center while minimizing disturbance of the front to back flow.
Im curious if the severe reduction in Reynolds number would mute any effect from this design in the air, or if the speed at which it works is too high for Road use.
In air,each step would trigger separation,creating a locked-vortex,then re-attachment downstream,only as long as there was airtight glazing underneath the louvers.(like the bed of a pickup with a tonneau cover)
There'd be a pool of dead air captured for the air to skip over.You can see this in the original video of Spirit at DARKO.
We can't really reduce the wetted area,since we're in a single fluid environment,unlike the boat hull's natural dual-fluid environment.
And Reynolds number is the same,as it's simply a function of vehicle length and velocity,which isn't altered.

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