474 research outputs found
Rationalisierung des Binnenschiffsbetriebes durch automatisch eingeleitete Änderung der Schiffsgeschwindigkeit bei Fahrt unter wechselnden Fahrwasserbedingungen
Fahrdynamische und Prüfstandserprobung des Z-Getriebes ZG-48/1 in Verbindung mit dem Kanalschubboot
The statistics of particle velocities in dense granular flows
We present measurements of the particle velocity distribution in the flow of
granular material through vertical channels. Our study is confined to dense,
slow flows where the material shears like a fluid only in thin layers adjacent
to the walls, while a large core moves without continuous deformation, like a
solid. We find the velocity distribution to be non-Gaussian, anisotropic, and
to follow a power law at large velocities. Remarkably, the distribution is
identical in the fluid-like and solid-like regions. The velocity variance is
maximum at the core, defying predictions of hydrodynamic theories. We show
evidence of spatially correlated motion, and propose a mechanism for the
generation of fluctuational motion in the absence of shear.Comment: Submitted to Phys. Rev. Let
Localization analysis of variationally based gradient plasticity model
The paper presents analytical or semi-analytical solutions for the formation
and evolution of localized plastic zone in a uniaxially loaded bar with
variable cross-sectional area. A variationally based formulation of explicit
gradient plasticity with linear softening is used, and the ensuing jump
conditions and boundary conditions are discussed. Three cases with different
regularity of the stress distribution are considered, and the problem is
converted to a dimensionless form. Relations linking the load level, size of
the plastic zone, distribution of plastic strain and plastic elongation of the
bar are derived and compared to another, previously analyzed gradient
formulation.Comment: 42 pages, 11 figure
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