Internal Body Aerodynamics

[rtj]

 

[phantomjock]

A LOT to be said about Anti-Dive and Anti-Squat too (touched on in the video).
As I recall the SpeedLab Corvette - has Zero Anti-dive/Zero Anti-Squat.
I like the idea of the forces through the CG. It would be an interesting ride.

Cheers - Jim

 

[BBShark]

I can see where removing what little dive there is under braking/on turn in would make it somewhat more difficult for the driver. But I'm not sure how that relates to tire front tire wear.

Is most front tire wear is due to braking into corners or going through the corner? Also, must of what I was seeing in these YT videos about McLaren, was related to brake temperatures. How do the deceleration forces change unless you are proportioning more braking to the rear tires (probably not a great idea).

 

[rtj]

I think he mentions the reason why keeping downforce constant from the underbody wing helps keep tires cooler.

When the downforce changes suddenly, the traction forces change rapidly, loading and unloading tires. The sudden changes in load is responsible for wear and heat, I believe is what he reasoned.

Pretty amazing that so many people are studying this to try and figure out their secret.

 

[BBShark]

I don't understand how the brakes run cooler because of anti dive. The total (all 4 wheels) of rotational/frictional forces acting on the brakes that slow a mass of X from 200mph to 100mph are the same regardless of weight transfer. The only way to deploy and incredible amount of drag (think a parachute)b or transfer braking forces from front to back. That sounds like a very bad idea.

 

[rtj]

If you have less downforce your wheels have less traction, I’m thinking more pedal pressure (clamping force) to achieve the same braking force.

Second, if you have lots of traction, you are less likely to need brakes.

Third, unloading and loading the tires suddenly due to big changes in downforce, would also translate to big brake force changes. Those big spikes would cause temps to spike.

Just throwing out some guesses. Probably other factors.

 

[rtj]

Hey BBShark, I asked google AI. Here is the answer it gave:

In F1, changes in tire downforce can indeed affect brake heating due to the interconnectedness of aerodynamics, tire grip, and braking systems. Increased downforce leads to greater grip, which in turn allows for more aggressive braking and higher deceleration rates. This, in turn, increases the heat generated by the brakes as they convert the car's kinetic energy into thermal energy.

Here's a more detailed explanation:

• Downforce and Grip:
  Downforce, generated by the car's aerodynamics (particularly wings and the underbody), increases the force pressing the tires onto the track. This translates to more grip, allowing the tires to handle higher cornering speeds and, significantly, more braking force.
  
  
• Braking Performance:
  When a car brakes, the brake pads or calipers apply pressure to the brake rotors, converting the car's kinetic energy into heat through friction. More downforce allows for more braking force to be applied without the wheels locking up, resulting in a higher deceleration rate and thus, more heat generated.
  
  
• Weight Transfer:
  During braking, weight shifts from the rear to the front of the car. This weight transfer is influenced by downforce. With more downforce, the weight transfer is more pronounced, potentially leading to more heat being transferred to the front brakes.
  
  
• Brake Cooling:
  F1 cars have sophisticated brake cooling systems, including ducts and vents, to manage the extreme heat generated during braking. However, the effectiveness of these systems can be influenced by the aerodynamic setup and the amount of heat generated, which is directly impacted by downforce changes.
  
  
• Brake Balance:
  F1 teams adjust the brake balance (the distribution of braking force between the front and rear wheels) based on various factors, including downforce levels and track conditions. More downforce can necessitate a shift in brake balance to ensure optimal braking performance and prevent overheating.
  
  
• Tire Temperature:
  Brakes can also affect tire temperature, as heat from the brakes can be transferred to the wheels and tires. This is why F1 teams carefully manage tire temperatures to optimize grip and performance.
  
  
• Tire Wear:
  Excessive heat can lead to tire degradation, potentially causing blistering or other issues. Therefore, teams must carefully balance braking performance with tire management.