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Old 10-14-2015, 06:43 PM   #48 (permalink)
aerohead
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trumpet

Okay,thanks!
From fluid mechanics,any diverging nozzle should never have a wall angle exceeding 7-to-8-degrees,or separation/turbulence will occur.I suffered from this at Bonneville by mimicing a Mustang GT diffuser (which I had to close off completely with cardboard and duct tape).
The 'trumpet' is a good technology though if tuned in a tunnel.
Recently,the Bochum University team used it on their WSC car

In 1978,Morelli used it on his CNR concept,creating wheel fairings to enclose the diffuser,helping to achieve zero-lift.

The 2nd-gen Prius has a fine 'trumpet'.
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