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aerohead · 05-24-2010, 05:06 PM

In automotive applications,the aft-body performance is governed by quality flow arriving from the fore-body.
The FLUIDs professor/textbook writers say that below 250 mph,a semispherical nose is plenty good and to concentrate on the aft-body for drag reduction.
The add-on nose to the CRX,which is in the direction of where you're going with the Porsche,made no measurable difference at 100 mph.
I don't think it is physically possible for any nose mod,regardless of how 'slick' it is,to make a significant showing at the pump,driving at posted speed limits.I do think that if you are going to modify the back of the car,then a really clean nose will help in that context.
With respect to the Orion,I don't know if that's germane to what we do.
When at DaNang,an Airman -of-the-Month won a back-seat ride in an F-4 Phantom.An avionics guy had not properly fastened the nose radome and they lost the whole thing in flight,causing the radar antennae to be shredded away by the airstream.The pilot had no problem with flight stability,however a hydraulic line had been severed,with time the plane would become un-fliable,and with the fluid all over the windscreen he had no forward vision.
They talked them down okay.The pilot was unshaken,the 'Airman' had to change his clothes.
And the thing about fish,they're governed more by skin friction,with the 833 times more dense water,than they are with profile drag,of which neither of the fish possess.
The Bluefin has the ' lowest' Frontal Cd of fish but is not the fastest fish.That title goes to the sailfish,clocked at over 60-mph.And for 'sustained' velocity,the bottlenose dolphin is given the credit,at around 30-mph and bursts to 45.
If memory serves me,Hertel gives the lowest frontal Cd of any measured 'structure' to the gentoo penguin.

05-24-2010, 05:06 PM	#34 (permalink)
aerohead Master EcoModder Join Date: Jan 2008 Location: Sanger,Texas,U.S.A. Posts: 16,320 Thanks: 24,442 Thanked 7,387 Times in 4,784 Posts	nose In automotive applications,the aft-body performance is governed by quality flow arriving from the fore-body. The FLUIDs professor/textbook writers say that below 250 mph,a semispherical nose is plenty good and to concentrate on the aft-body for drag reduction. The add-on nose to the CRX,which is in the direction of where you're going with the Porsche,made no measurable difference at 100 mph. I don't think it is physically possible for any nose mod,regardless of how 'slick' it is,to make a significant showing at the pump,driving at posted speed limits.I do think that if you are going to modify the back of the car,then a really clean nose will help in that context. With respect to the Orion,I don't know if that's germane to what we do. When at DaNang,an Airman -of-the-Month won a back-seat ride in an F-4 Phantom.An avionics guy had not properly fastened the nose radome and they lost the whole thing in flight,causing the radar antennae to be shredded away by the airstream.The pilot had no problem with flight stability,however a hydraulic line had been severed,with time the plane would become un-fliable,and with the fluid all over the windscreen he had no forward vision. They talked them down okay.The pilot was unshaken,the 'Airman' had to change his clothes. And the thing about fish,they're governed more by skin friction,with the 833 times more dense water,than they are with profile drag,of which neither of the fish possess. The Bluefin has the ' lowest' Frontal Cd of fish but is not the fastest fish.That title goes to the sailfish,clocked at over 60-mph.And for 'sustained' velocity,the bottlenose dolphin is given the credit,at around 30-mph and bursts to 45. If memory serves me,Hertel gives the lowest frontal Cd of any measured 'structure' to the gentoo penguin.