There was a post on this a few years ago as someone noticed the effect going through the Monaco tunnel.
In my opinion it's due to the static toe-out on the front axle. Toe-out means that the external wheel starts (in a straight line) with a slip angle opposing that of which it will adopt during the corner. So for the first few angles of steering lock, the external wheel's slip angle reduces, passes through zero and then increases again.
That means that for large radius corners, which use little steering lock, the inside wheel is doing most of the cornering effort.
Here is the post from the previous thread
Inside fronts heating up mid corner?:
Tim.Wright wrote:I've done a few calcs and I'm sure its the static toe...
Whats happening is that the lateral acceleration is so low that the slip angles at the tyres that are required to do the corner are about the same as the slip angle imposed by the static toe setting. This results in the inside wheel having a slip angle about double of the static toe value and the outside wheel has zero slip, so is generating no heat.
Here is my justification:
Consider the car driving straight on the entry to the tunnel. In this condition, the slip angles on the front tyres are equal to the static toe angles but opposing left to right.
Assuming 1mm of toe = arctan(1mm/13") = 0.35deg.
Using the ISO convention, that means left and right slip angles of:
Left = +0.35deg // Right = -0.35deg
...occur from driving in a straight line.
During the light curve in the tunnel, the car turns right and the slip angles move in a NEGATIVE direction for both tyres. You can see already that the right (inside) wheel is already negative so it will increase its slip angle. The outside wheel is positive so first it must decrease its slip angle. So its possible that the outside wheel can have zero slip angle while the car is cornering.
To see if this is realistic for the case of the Monaco tunnel we can make a little model (concentrating on the front axle only)...
Input data:
mass = 650kg
distribution = 45%f
driver: Alonso
laptime: -0.6s
LatAcc = 1G (guesstimation of lateral acceleration through the tunnel)
Front cornering stiffness = 4830N/deg per tyre [Milliken F1 tyre c. 1993]
Assumptions:
Tyres are in the linear range
No lateral load transfer
This results in a front axle slip angle of -0.296deg
Note, this is very similar to the static toe value. If we then superimpose the slip angle from the static toe to the axle slip of -0.296deg we get the individual wheel slips:
Left slip = 0.35 - 0.296 = 0.054deg
Right slip = -0.35 - 0.296 = -0.646deg
So we can see that the left (outside) wheel has very little slip angle compared to the inside one which is doing pretty much all the work.
If we use the cornering stiffness then to find the indiviual wheel Cornering forces we get:
Left = 0.054deg x 4830N/deg = 241N
Right = -0.646deg x 4830N/deg = -3111N
Which confirms the outside wheel is not only doing nothing but its lateral force is slightly towards the outside of the turn. This is not a problem because this corner is not grip limited.
If we assume the car is doing 200km/h at this point we can calculate the power input to the tyre which creates the temperature increase that we see from the onboard camera:
P_left = Vel * SlipAngleL * ForceL = 11 Watts
P_right = Vel * SlipAngleR * ForceR = 1943 Watts
So this is why you see the temperature increase on the inside wheel. It is receiving approx 2kW of heating while the outside wheel receives only 0.011kW.
In conclusion, its the static toe angles which are causing an offset to the left and right slip angles. In a low acceleration corner, the slip angles are so small (due to the high cornering stiffness tyres) that the slip angles are just barley enough to cancel the static toe slip on the outside wheel.
Why don't you see this in other corners? In a normal corner which is grip limited, there is significant lateral load transfer which means the outside wheel has a much larger cornering stiffness than the inside wheel. Also, your slip angles will be significantly more than the static toe so there is no chance that the outside wheel is running at zero slip.
