The use of Coulomb’s friction law with the principles of classical rigid-body dynamics introduces mathematical inconsistencies. Specifically, the forward dynamics problem can have no solutions or multiple solutions. In these situations, compliant contact models, while increasing the dimensionality of the state vector, can resolve these problems. The simplicity and efficiency of rigid-body model...

Wearless dry friction of an elastic block of weight N , driven by an external force F over a rigid substrate, is investigated. The slider and substrate surfaces are both microscopically rough, interacting via a repulsive potential that depends on the local overlap. The model reproduces Amontons’s laws which state that the kinetic friction force is proportional to the normal loading force N and ...

We present a microscopic theory for dynamic friction on an intramolecular vibrational coordinate of a diatomic molecule dissolved in a simple liquid. Previous theoretical approaches to calculating dynamic friction have either used molecular hydrodynamics or employed a concept of instantaneous normal modes. Both methods have their limitations: molecular hydrodynamics is unable to correctly descr...

Friction is a desired property in quantum dynamics as it allows for localization, prevents backscattering, and is essential in the description of multistage transfer. Practical approaches for friction generally involve memory functionals or interactions with system baths. Here, we start by requiring that a friction term will always reduce the energy of the system; we show that this is automatic...

It is shown using a method based on a modified version of the mean field theory of Miklavic and Marcelja [J. Phys. Chem. 92, 6718 (1988)] that it should be possible for osmotic pressure due to the counterions associated with the two polyelectrolyte polymer brush coated surfaces to support a reasonable load (i.e., about 10(6) Pa) with the brushes held sufficiently far apart to prevent entangleme...

To model cohesionless granular flow using continuum theory, the usual approach is to assume the cohesionless Coulomb-Mohr yield condition. However, this yield condition assumes that the angle of internal friction is constant, when according to experimental evidence for most powders the angle of internal friction is not constant along the yield locus, but decreases for decreasing normal stress c...

Introduction: Although the theory of Roche [1] for the tidal disruption limits of orbiting satellites assumes a fluid body, a length to diameter of exactly 2.07:1, and a particular body orientation, the theory is commonly applied to the satellites of the solar system and to small asteroids and comets passing nearby a planet. Clearly these bodies are neither fluid nor generally that elongated, s...

The seizure process has been considered from the non-equilibrium thermodynamics and self-organization theory standpoints. It has been testified that, for the intensification of powder mix particles seizing with the substrate during spraying, it is required that relatively light components of the powder mix should be preferably transferred into the friction zone. The theory inferences have been ...

The theory of Battisti and Clarke (1982) to calculate analytically barotropic tidal currents across 'smooth' continental margin topography is shown to be valid near shore on 'nonsmooth' continental shelves. The theory includes longshore gradients and friction and produces formulae easily evaluated with coastal sea level data. The tidal currents across three such shelves (West Florida, south of ...