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Rolling resistance, sometimes called rolling friction or rolling drag, is the force resisting the motion when a body (such as a ball, tire, or wheel) rolls on a surface. It is mainly caused by non-elastic effects; that is, not all the energy needed for deformation (or movement) of the wheel, roadbed, etc., is recovered when the pressure is removed.
SAE J1269 and SAE J2452 performed on new tires. SAE J2452 is a standard defined by the Society of Automotive Engineers [1] to measure the rolling resistance of tires. [2] Where the older standard, SAE J1269, produces measurements of rolling resistance under steady-state (i.e. thermally equilibrated) operating conditions, SAE J2452 produces measurements during a transient history of speed that ...
rolling friction. In the case of bodies capable of rolling, there is a particular type of friction, in which the sliding phenomenon, typical of dynamic friction, does not occur, but there is also a force that opposes the motion, which also excludes the case of static friction. This type of friction is called rolling friction.
The rolling resistance coefficient (RRC) indicates the amount of force required to overcome the hysteresis of the material as the tire rolls. Tire pressure, vehicle weight and velocity all play a role in how much force is lost to rolling resistance. The basic model equation for SAE J2452 is: Rolling Resistance (N / lbs) = (+ +) where: is the ...
Classical solutions based on the half-space approach are: Hertz solved the contact problem in the absence of friction, for a simple geometry (curved surfaces with constant radii of curvature). Carter considered the rolling contact between a cylinder and a plane, as described above.
[3] [4] In 1882, Hertz solved the contact problem of two elastic bodies with curved surfaces. This still-relevant classical solution provides a foundation for modern problems in contact mechanics. For example, in mechanical engineering and tribology, Hertzian contact stress is a description of the stress within mating parts. The Hertzian ...
This template displays the symbol for coefficient of rolling resistance with an optional link to Rolling resistance (link=yes) and an optional value. If long=yes then the phrase 'rolling resistance of' is added to the front to make it easier to read as part of a full sentence.
where F is the rolling resistance force (shown in figure 1), r is the wheel radius, b is the rolling resistance coefficient or coefficient of rolling friction with dimension of length, and N is the normal force (equal to W, not R, as shown in figure 1). Equating the above two equations, and solving for b, gives b = Crr·r.