Coefficient of Drag for Touring & Pure..... What does this mean?

[Halodde]

So, here's a question for those with Airs already. When you change modes (smooth, swift, sprint), does the car change anything else besides increase the power and stiffen the suspension? Does it, for example, become lower to the ground thereby possibly changing the drag? Or potentially increase the drag? @GearHead example of F1 got me thinking about that because those cars are able to change the drag during a race (DRS) depending on various conditions. Obviously, less drag correlates with faster straight line speeds. However, handling requires more drag/downforce to keep the rubber on the road. Obviously, we're not dealing with track cars here. But, I know the Audi S6 for example, actually can change things like ride height.

 

[borski]

So, here's a question for those with Airs already. When you change modes (smooth, swift, sprint), does the car change anything else besides increase the power and stiffen the suspension? Does it, for example, become lower to the ground thereby possibly changing the drag? Or potentially increase the drag? @GearHead example of F1 got me thinking about that because those cars are able to change the drag during a race (DRS) depending on various conditions. Obviously, less drag correlates with faster straight line speeds. However, handling requires more drag/downforce to keep the rubber on the road. Obviously, we're not dealing with track cars here. But, I know the Audi S6 for example, actually can change things like ride height.

No. It doesn’t have an air suspension, so doesn’t get lower or higher. The drag doesn’t change, just the suspension stiffness, handling, and power delivery.

 

[NoseyReporter]

DRS on a F1 car refers to one of the rear wing element opening to allow air to pass through the rear wing element instead of hitting it. Essentially you take a rear wing, reduce the angle of attack, thereby reducing drag and downforce generated.

It doesn't automatically do this based on driving conditions. It is driver actuated and only allowed between designated points on the track.

F1 cars do have very trick suspension that can raise and lower based on aero load. And they also have ultra trick front wings that can deflect as speed increases. But I doubt we would ever see this on a luxury sedan.

Air suspension that lowers at speed, may help CD. I'm not sure. But really what it would help with is accelerating the flow of air under the car, especially if it's flat bottom. This would help produce more downforce as the car speeds up. I think the latest gen of F1 cars is highly focused on controlling air on the bottom of the car, a large majority of down force is generated this way.

 

[Slam08]

DRS on a F1 car refers to one of the rear wing element opening to allow air to pass through the rear wing element instead of hitting it. Essentially you take a rear wing, reduce the angle of attack, thereby reducing drag and downforce generated.

It doesn't automatically do this based on driving conditions. It is driver actuated and only allowed between designated points on the track.

F1 cars do have very trick suspension that can raise and lower based on aero load. And they also have ultra trick front wings that can deflect as speed increases. But I doubt we would ever see this on a luxury sedan.

Air suspension that lowers at speed, may help CD. I'm not sure. But really what it would help with is accelerating the flow of air under the car, especially if it's flat bottom. This would help produce more downforce as the car speeds up. I think the latest gen of F1 cars is highly focused on controlling air on the bottom of the car, a large majority of down force is generated this way.

The latest F1 cars have the porpoising issue with the changes in design.

Apparently they get too low and lose the downforce altogether when air doesn’t flow underneath and then pop up

What is porpoising? F1’s aerodynamic phenomenon explained

F1’s new rules for 2022 have seen a return of ‘porpoising’. But, um, what is porpoising? TG has your back

www.topgear.com

 

[NoseyReporter]

Yea they have an unwanted stall of the air.

The new cars are very fun to watch. I can't wait to see what next year brings, especially with Merc coming I to its own these last few races.

 

[Halodde]

I can't wait to see an F1 car generate enough downforce to drive across the ceiling

 

[MorganB]

It’s the new 20” wheels and aero covers. I confirmed this last night.

Thank you! I wondered what they were talking about.

 

[emoylv]

It’s the new 20” wheels and aero covers. I confirmed this last night.

borski: Are you saying that the coefficient of drag at 0.197 is with the 20" wheels? If so, is the 425-mile range also with the 20" wheels? Or is Lucid mixing apples and oranges?

 

[borski]

borski: Are you saying that the coefficient of drag at 0.197 is with the 20" wheels? If so, is the 425-mile range also with the 20" wheels? Or is Lucid mixing apples and oranges?

I cannot answer the latter as I don't know. But yes to the first question.

 

[Pax]

During a Reddit AMA Derek answered this - basically in production they were able to achieve lower drag coefficient metrics compared to pre-production.

https://www.reddit.com/r/LUCID/comments/yyq9cv/_/iwvm1ga

 

[SDHacker]

No. It doesn’t have an air suspension, so doesn’t get lower or higher. The drag doesn’t change, just the suspension stiffness, handling, and power delivery.

Adding to what @borski wrote, smooth has the highest resistance when pushing the go pedal and requires the most pedal travel before anything happens. Waiting for Lucid to let me combine the swift go pedal with the smooth suspension.

 

[MoniputerLM]

Adding to what @borski wrote, smooth has the highest resistance when pushing the go pedal and requires the most pedal travel before anything happens. Waiting for Lucid to let me combine the swift go pedal with the smooth suspension.

GM lets you build a custom drive mode in the C8 Corvette, and so does Mercedes in the AMG EQS. Lucid should have no trouble doing this at some point.

 

[Rchie]

GM lets you build a custom drive mode in the C8 Corvette, and so does Mercedes in the AMG EQS. Lucid should have no trouble doing this at some point.

I hope that they work on doing this. But it would make sense if they are prioritizing more stability on their software.

 

[changinator]

I cannot answer the latter as I don't know. But yes to the first question.

Are you sure this is the right answer? Who told you this at the debut? I just don't understand how the 20" wheels would decrease the Lucid Air drag coefficient more than the 19" wheels if the vehicle gets more range but worse drag coefficient on the 19" wheels. When I asked, they told me it was just minor modifications to the front bumper that allowed for better flow to the underbody, similar to what Derek Jenkins said in his AMA

 

[Jeanwoodie]

Fellas, I'm a newbie here and some of the terminology used yesterday doesn't make sense so hopefully you car guys can explain this to me. During yesterday's event, Derek talked about the improvement of Air's coefficient of drag to an industry leading 0.197cd around the 9:50 mark of the presentation. I assume this is for the Touring and Pure Models so I have a few questions:

1) What does coefficient of drag mean in layman's terms? Does is mean the car sits a bit lower and is sleeker?
2) How is it applied to Touring & Pure?
3) Does this mean there was a slight body/frame modification for the Touring and Pure as opposed to Grand Touring & Dream?

Thanks in advance!

Lucid GR’s have a frontal area of 76” wide by 56” high which is 4,256 square inches. If they were a flat plate the CD would be 1
However the CD of 0.197 means that in wind tunnel testing the actual drag is equivalent to a flat plate of 897 square inches.

 

[emoylv]

Are you sure this is the right answer? Who told you this at the debut? I just don't understand how the 20" wheels would decrease the Lucid Air drag coefficient more than the 19" wheels if the vehicle gets more range but worse drag coefficient on the 19" wheels. When I asked, they told me it was just minor modifications to the front bumper that allowed for better flow to the underbody, similar to what Derek Jenkins said in his AMA

There are several factors that influence range. The 20" wheels may have a lower coefficient of drag but that does not take into account the rolling resistance of the tire which is most likely higher in the summer tire. I suspect that the 425-mile range is with the 19" wheels and A/S tires. That's why I asked borski if the CD number was with the 19" or 20" wheels; he confirmed 20". The CD with the 19" wheels may be higher but nobody has confirmed that on this forum (yet).

 

[borski]

Are you sure this is the right answer? Who told you this at the debut? I just don't understand how the 20" wheels would decrease the Lucid Air drag coefficient more than the 19" wheels if the vehicle gets more range but worse drag coefficient on the 19" wheels. When I asked, they told me it was just minor modifications to the front bumper that allowed for better flow to the underbody, similar to what Derek Jenkins said in his AMA

Peter Rawlinson.