( POSSIBLE ) Invite to the folks at A2 wind tunnel for a one time Q&A session here.

[Cd]

Hey everyone, I'm not sure if they have enough time to drop by the forum, but the guys at A2 windtunnel MIGHT be able to answer a few questions.
Please think of what you would like to ask and post in this thread.
Please limit the number of questions you ask, since their time is limited .
Nothing is set in stone regarding this, since it is just an invite, but I did speak with Geoff earlier today, and he says he will ask his dad about it.

And FYI Gary Eaker ( the dad ) personally worked on the aerodynamics on the EV-1 !
This is the same guy that dropped the cD on a 1981 Camaro to an amazing .201 !

- Thanks !

[freebeard]

It's hard to think of something that's not too specific. How about: What are the popular misconceptions?

[aerohead]

Since fuel economy for ICE vehicles and 'range' for BEVs is of much interest, and since low drag factors so strongly into that calculus; in light of Wolf Hucho's comment in 1986 that, Cd 0.09 was 'technologically feasible', I'd be very interested in knowing how they might navigate that magnitude of drag reduction.

[j-c-c]

Question 1: When cars are being tested in the tunnel, is suspension height locked or left free to react and measured or tested both ways?
Question 2: how much impact does an operating engine at speed have on results, air intake, fan, exhaust, etc?

[Cd]

Here are a few questions I have, since I see there are not that many posted in the thread:
Blunt fronts, versus pointy front ends.
These two cars have the exact same cD ( nevermind cDxA in this example )


This car you tested had a .201 cD

, yet this other one had a .21 cD - so actually higher !

Of what importance is a "pointy" front end at normal road speeds ?
How does the increase in pressure on a blunt front effect drag ?
In these examples, the car has a very blunt front :

How does the air stay attached with such sharp edges at the corners ? ( in green )


And on this other car, how does air remain attached, despite the flat, upright windshield ?


On the example Camaro above, there is also a large portion of the tire exposed to the wind ( in green on the image ) Gary tested some side spats that one would think would deflect air away fron this area, yet they did not change the cD.

Finally, since the Lexus LS430 had such a good cD ( the .25 example at the start ) yet has a 3 box design, could the car do even better with a boattail ?
( silly looking, yes, but as an example )

All these questions have been covered on this forum , but I would like your opinions as well.
- Thanks !

[Phase]

Originally Posted by Cd

Here are a few questions I have, since I see there are not that many posted in the thread:
Blunt fronts, versus pointy front ends.
These two cars have the exact same cD ( nevermind cDxA in this example )


This car you tested had a .201 cD

, yet this other one had a .21 cD - so actually higher !

Of what importance is a "pointy" front end at normal road speeds ?
How does the increase in pressure on a blunt front effect drag ?
In these examples, the car has a very blunt front :

How does the air stay attached with such sharp edges at the corners ? ( in green )


And on this other car, how does air remain attached, despite the flat, upright windshield ?


On the example Camaro above, there is also a large portion of the tire exposed to the wind ( in green on the image ) Gary tested some side spats that one would think would deflect air away fron this area, yet they did not change the cD.

Finally, since the Lexus LS430 had such a good cD ( the .25 example at the start ) yet has a 3 box design, could the car do even better with a boattail ?
( silly looking, yes, but as an example )

All these questions have been covered on this forum , but I would like your opinions as well.
- Thanks !

seems like optimal front is the '' indented front'' like teslas, mercedez eqxx, hyundai ioni 6 and so on... feeds air into the air curtans

[Cd]

Hello everyone. I have phone Q&A session with Gary Eaker of A2 tomorrow.

He prefers to speak over the phone, rather than type.
Therefore, I will ask him some of these questions and try and post back to the forum with his reply.

If you have any other questions for him, please post them to this thread.

[Phase]

ask if they do any youtuber collaboration discounts

[j-c-c]

Originally Posted by Cd

Hello everyone. I have phone Q&A session with Gary Eaker of A2 tomorrow.

He prefers to speak over the phone, rather than type.
Therefore, I will ask him some of these questions and try and post back to the forum with his reply.

If you have any other questions for him, please post them to this thread.

additional Questions:
#3 what is the max speed they test at?
#4 how many runs per set-up to verify/avg results for each modification?
#5 Is any tuff testing w/video possible during test runs, lighting, thru viewing window, etc?
#6 Are there any general suggestions to give regarding the sequence of items tested, as they are likely to interact with each other, without excessively having to take steps backwards? Like work with the front of the car modifications first, and then start at the back or at both ends of the car alternating modifications?
#7 For best tunnel management, start with all mods in place and test by test remove a modification, as removing is often faster than installing?
#8 what is the time usually allocated for just one test run for one set-up, not including any set-up or modifications or reruns.
#9 If one has as primary objective F&R DF measurements with drag considerations secondary, is there any significant difference in the test programs vs mainly looking for drag reduction?

[pgfpro]

Awesome thread, somehow, I missed this one?