Aerodynamic Bumper

[freebeard]

Originally Posted by Xist

Lowering the center of gravity is good.

...hence my avatar pic.

[deejaaa]

Originally Posted by u.steinlechner

...........What do you think about the design and wich car model should be the first for a serial produced bumper....

the MK4 Jetta, AKA Bora, of course.

[NeilBlanchard]

Does the nose function as an aerodynamic improvement? The Mercedes Bionic (aka the Boxfish) has a similar nose and it does seem to have a benefit - maybe to initiate the motion of the air, since it is the first portion of the car to push it aside.

[u.steinlechner]

Hi,

this are the results from the measurement in the windtunnel.

Ulrich


CW Wiederstand drag
CA Auftrieb gesamt lift
Cav Auftrieb vorne lift front
Cah Auftrieb hinten lift rear



Serienzustand, Original, radiator grill open
speed 140 km/h
CW 0,323
CA 0,0402
CAv -0,0223
CAh 0,0626



Xanon aerodynamic bumper with vortex generator, air intake open
speed 140 km/h
CW 0,2971
CA 0,0256
CAv -0,1053
CAh 0,1309


Xanon aerodynamic bumper without vortex generator, air intake open
speed 140 km/h
CW 0,2961
CA 0,0213
CAv -0,097
CAh 0,1184

[u.steinlechner]

Originally Posted by NeilBlanchard

Does the nose function as an aerodynamic improvement? The Mercedes Bionic (aka the Boxfish) has a similar nose and it does seem to have a benefit - maybe to initiate the motion of the air, since it is the first portion of the car to push it aside.

Hi Neil,

the nose is a improvement.
By replacing only of the bumper and radiator grill, aerodynamics improve dramatic.
See wind tunnel results

But it is not based on the boxfish.

In my concept, two bionic shapes are used.

On the upper side, the nose of the penguin as (Stufenvorlaufkörper) to accelerate and slow down the air several times bevor it reache the main body.

On the bottom, the stingray have good characteristics in the ground effect.
So the bumper is the synthesis of several requirements and bionic solutions.


Bionic is the science of copying nature for technical applications

The nose is the result from what I have learned from my "Xanon X1" concept.


Image: Xanon X1

The air intake is the result of studies of air intake in front of the wheels, because wheels can make 30% of aerodynamic drag.

(But designers like to show big wheels)

Last but not least, it is not important to model the shape of the car, but the distribution of pressure in front of the car.

Rule: Aerodynamics starts not at the object but in a distance befor.

Ulrich

[aerohead]

It seems like the bumper serves to minimize the airflow volume through the cooling system,harvest the remaining cooling air from a lowered frontal stagnation location,while limiting stagnation pressure from the base underside of the original M-B nose,thereby restricting underbody flow.All good!
The airflow would be deforming well in advance of the car even without the new nose,as Ludwig Prandtl reported on in the 1920s,with his 'lines of discontinuity.'
Here you can see it with the Schl'o'rwagen

The quasi-NACA inlet at the driver's side upper grille location brings in the rest of the needed air.
It's a stylish way to kill a couple birds with the same stone.

[u.steinlechner]

Hi aerohead,

the picture of the Schlör car shows smoke probes in the center line of the car.

The center line is a special place for nice pictures.

More important is the area beside the center line because the airflow will swap to the side of the car.



Ulrich

[Xist]

How do you prevent hydrolock?

[u.steinlechner]

Hi Xist,

the low air intake are only for the heat exchanger.

The air intake for the engine are in the origin height.

You can see it instead of the the radiator grill.

This air intake for the engine can also be a cause for the fuel efficiency, because there could be a higher pressure and airflow.



Ulrich

[renault_megane_dci]

Cool developement !

Can we have a glance underneath ?