Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - View Single Post

kach22i · 01-05-2021, 10:53 AM

Thank you for posting the video.

Is this thicker boundary layer air responsible for mitigating or jumping over the different angle between rear window glass and trunk on a saloon/sedan?

This intersection is usually accused of interrupting attached flow, however in wind tunnels with smoke the flow looks smooth, angle differences seem to disappear - especially with increased distance from surface.

Where are the greatest pressure differences measured at the rear of the car?

1. Between top and bottom

2. Between top and side

3. Between side and bottom

Only 4-planes of interaction on a rectangular section car/truck, correct?

I suspect the "Jet Pump" phenomena is greatest under the car where it is squeezed and partially contained by ground plane.

I have not read the PDF in the link below, but it could be related to this topic.

Review on Aerodynamic Drag Reduction of Vehicles
https://www.researchgate.net/figure/...fig1_330661575

01-05-2021, 10:53 AM	#4 (permalink)
kach22i Master EcoModder Join Date: Jul 2011 Location: Ann Arbor, Michigan Posts: 4,178 Thanks: 127 Thanked 2,802 Times in 1,968 Posts	Thank you for posting the video. Is this thicker boundary layer air responsible for mitigating or jumping over the different angle between rear window glass and trunk on a saloon/sedan? This intersection is usually accused of interrupting attached flow, however in wind tunnels with smoke the flow looks smooth, angle differences seem to disappear - especially with increased distance from surface. Where are the greatest pressure differences measured at the rear of the car? 1. Between top and bottom 2. Between top and side 3. Between side and bottom Only 4-planes of interaction on a rectangular section car/truck, correct? I suspect the "Jet Pump" phenomena is greatest under the car where it is squeezed and partially contained by ground plane. I have not read the PDF in the link below, but it could be related to this topic. Review on Aerodynamic Drag Reduction of Vehicles https://www.researchgate.net/figure/...fig1_330661575 __________________ George Architect, Artist and Designer of Objects 2012 Infiniti G37X Coupe 1977 Porsche 911s Targa 1998 Chevy S-10 Pick-Up truck 1989 Scat II HP Hovercraft You cannot sell aerodynamics in a can............