Coupling rod energy models using local energy density

The knowledge of wear kinetics of thin soft lubricant or hard coatings under alternated sliding contact is of great interest for many industrial applications. Because the coating endurance is related to the substrate reaching condition, it has been shown that classical wear volume descriptions are not appropriated. A local damage description, based on a local friction dissipated energy density variable is then introduced. It consists to compare the coating endurance (i.e. number of sliding cycles) versus the maximum local energy density dissipated through the interface per sliding cycle. A “life time vs maximum dissipated energy density master curve” is obtained and rationalized through a parabolic evolution. The coating endurance is modelized through a simple ratio between an energy capacity variable, representative of the durability of the studied coating. Applied to hard coatings (TiN) the stability of this approach has been confirmed for solid lubricant coatings.

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Bonded interactions and the crystal chemistry of minerals: a review

Zeitschrift für Kristallographie - Crystalline Materials ◽

10.1524/zkri.2008.0002 ◽

2008 ◽

Vol 223 (01-02) ◽

pp. 01-40 ◽

Cited By ~ 19

Author(s):

G. V. Gibbs ◽

Robert T. Downs ◽

David F. Cox ◽

Nancy L. Ross ◽

Charles T. Prewitt ◽

...

Keyword(s):

Energy Density ◽

First Principles ◽

Quantum Mechanical ◽

Bond Critical Point ◽

Local Energy ◽

Molecular Chemistry ◽

Density Distributions ◽

Mechanical Methods ◽

Crystal Quartz ◽

Local Energy Density

Connections established during last century between bond length, radii, bond strength, bond valence and crystal and molecular chemistry are briefly reviewed followed by a survey of the physical properties of the electron density distributions for a variety of minerals and representative molecules, recently generated with first-principles local energy density quantum mechanical methods. The structures for several minerals, geometry-optimized at zero pressure and at a variety of pressures were found to agree with the experimental structures within a few percent. The experimental Si–O bond lengths and the Si–O–Si angle, the Si–O bond energy and the bond critical point properties for crystal quartz are comparable with those calculated for the H

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An integrated local energy density approach to notch low cycle fatigue life prediction

Engineering Fracture Mechanics ◽

10.1016/0013-7944(85)90064-5 ◽

1985 ◽

Vol 21 (1) ◽

pp. 187-202 ◽

Cited By ~ 4

Author(s):

P.A. Domas ◽

Stephen D. Antolovich

Keyword(s):

Fatigue Life ◽

Energy Density ◽

Life Prediction ◽

Low Cycle Fatigue ◽

Fatigue Life Prediction ◽

Local Energy ◽

Cycle Fatigue ◽

Local Energy Density

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LOCAL ENERGY-DENSITY FUNCTIONAL APPROACH TO MANY-BODY NUCLEAR SYSTEMS WITH S-WAVE PAIRING

International Journal of Modern Physics B ◽

10.1142/s0217979201006203 ◽

2001 ◽

Vol 15 (10n11) ◽

pp. 1684-1702 ◽

Cited By ~ 13

Author(s):

S. A. FAYANS ◽

D. ZAWISCHA

Keyword(s):

Energy Density ◽

Nuclear Matter ◽

Density Gradient ◽

Density Functional ◽

Effective Density ◽

Local Energy ◽

Energy Density Functional ◽

Density Dependent ◽

Nuclear Systems ◽

Local Energy Density

The ground-state properties of superfluid nuclear systems with 1S0 pairing are studied within a local energy-density functional (LEDF) approach. A new form of the LEDF is proposed with a volume part which fits the Friedman-Pandharipande and Wiringa-Fiks-Fabrocini equation of state at low and moderate densities and allows an extrapolation to higher densities which preserves causality. For inhomogeneous systems, a surface term is added, with two free parameters, which has a fractional form like a Padé approximant containing the square of the density gradient in both the numerator and denominator. In addition to the direct and exchange Coulomb interaction energy, an effective density-dependent Coulomb-nuclear correlation term is included with one more free parameter. A three-parameter fit to the masses and radii of about 100 spherical nuclei has shown that the latter term gives a contribution of the same order of magnitude as the Nolen-Schiffer anomaly in the Coulomb displacement energy. The root-mean-square deviations from experimental masses and radii with the proposed LEDF come out about a factor of two smaller than those obtained with the conventional functionals based on the Skyrme or finite-range Gogny force, or on relativistic mean-field theory. The generalized variational principle is formulated leading to the self-consistent Gor'kov equations which are sovled exactly, with physical boundary conditions both for the bound and scattering states. The method is used to calculate the differential observables such as odd-even mass differences and staggering in charge radii. With a zero-range density-dependent cutoff pairing interaction incorporating a density-gradient term, the evolution of these observables is reproduced reasonably well, including the kinks at magic neutron numbers and the sizes of the associated staggering. An extrapolation from the pairing properties of finite nuclei to pairing in infinite nuclear matter is discussed. A "reference" value of the pairing gap ΔF≈ 3.3 MeV is found for subsaturated nuclear matter at about 0.65 of the equilibrium density. With the formulated LEDF approach, we study also the dilute limit in both the weak and strong coupling regimes. Within the sum rules approach it is shown that the density-dependent pairing may also induce sizeable staggering and kinks in the evolution of the mean energies of multipole excitations.

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Bounds on the local energy density of holographic CFTs from bulk geometry

Classical and Quantum Gravity ◽

10.1088/0264-9381/33/22/225003 ◽

2016 ◽

Vol 33 (22) ◽

pp. 225003 ◽

Cited By ~ 4

Author(s):

Sebastian Fischetti ◽

Andrew Hickling ◽

Toby Wiseman

Keyword(s):

Energy Density ◽

Local Energy ◽

Local Energy Density

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