Shear stress on a tire from a puddle of water

Click For Summary
SUMMARY

The discussion focuses on calculating the shear stress on a tire when a car traveling at 65 mph encounters a 1-inch deep puddle of water. The relevant parameters include a tire radius of 16 inches and a viscosity of 2.344 x 10^-5 lbf*s/ft². The shear stress is determined using the formula τ = μ * u / y, where τ represents shear stress, μ is viscosity, u is the velocity of the car, and y is the depth of the water. The velocity at the bottom of the tire is considered to be zero due to contact with the road surface, impacting the calculation of shear stress.

PREREQUISITES
  • Understanding of fluid dynamics principles, specifically shear stress calculations.
  • Familiarity with the concept of viscosity and its units.
  • Knowledge of angular velocity and its relationship to linear velocity.
  • Basic algebra skills for manipulating equations.
NEXT STEPS
  • Study the effects of tire radius on shear stress calculations.
  • Explore the relationship between velocity and shear stress in fluid mechanics.
  • Learn about the impact of different fluid viscosities on shear stress in automotive applications.
  • Investigate the role of tire design in handling water on road surfaces.
USEFUL FOR

Automotive engineers, physics students, and anyone interested in the dynamics of vehicle performance in wet conditions will benefit from this discussion.

Elyk
Messages
1
Reaction score
0

Homework Statement


A car is moving at 65 mph and hits a puddle of water 1 inch deep. What is the shear stress on the tire from the puddle of water if the radius of the tire is 16 inches.
r = 16 inches
u = 65 mph
y = 1 inch
mu = viscosity = 2.344*10^-5 lbf*s/ft^2

Homework Equations


angular velocity:
omega = u/r
shear stress from fluid:
tau = mu*u/y

The Attempt at a Solution


Velocity at the bottom of the tire is equal to the velocity of the car:
u = omega * r
shear stress on the tire:
tau = mu*u/y
I'm not sure about the velocity at the bottom of the tire.
 
Physics news on Phys.org
Presumably the bottom of the tire is in contact with the road surface and not slipping, so its instantaneous velocity will be zero.
 

Similar threads

Replies
7
Views
3K
  • · Replies 11 ·
Replies
11
Views
2K
Replies
9
Views
3K
  • · Replies 3 ·
Replies
3
Views
10K
  • · Replies 6 ·
Replies
6
Views
2K
Replies
7
Views
2K
  • · Replies 9 ·
Replies
9
Views
4K
  • · Replies 8 ·
Replies
8
Views
19K
  • · Replies 6 ·
Replies
6
Views
19K
  • · Replies 1 ·
Replies
1
Views
8K