Results 251 to 260 of about 282,392 (296)

Low-temperature slip along intergrain boundaries

Low Temperature Physics, 2017
Equations are derived for slip in a disordered atomic layer which describe diffusive creep as well as high-speed slip at low temperatures. An exact solution for the slip velocity is found in the form of a functional of the distribution function of the threshold shear stresses in the slip layer. The relationship between the microscopic parameters of the
A. S. Bakai, P. N. Lazarev
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Lamellar boundary slip in polyethylene

Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences, 1966
Mechanical relaxation in polyethylene specimens prepared in various ways has been studied at 0*67 c/s and by creep experiments of 35 min duration in order to elucidate the mechanisms of the α' and α' relaxations. Internal friction measurements were made from 20 to 120 °C and creep measurements from 14 to 85 °C.
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Navier–Stokes equations with slip boundary conditions

Mathematical Methods in the Applied Sciences, 2007
AbstractIn this paper, we consider incompressible viscous fluid flows with slip boundary conditions. We first prove the existence of solutions of the unsteady Navier–Stokes equations in n‐spacial dimensions. Then, we investigate the stability, uniqueness and regularity of solutions in two and three spacial dimensions.
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Slip boundary conditions in Couette flow

Physica A: Statistical Mechanics and its Applications, 1999
Abstract The influence of a boundary layer in the Couette flow of a rarefied gas is studied by means of the Grad's solution for the Boltzmann equation. The boundary conditions satisfied by the relevant Grad's moments are calculated through the simplest wall model which is characterized by some accommodation coefficients in the surface.
J. López-Lemus, R.M. Velasco
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THERMAL BOUNDARY LAYER IN SLIP FLOW REGIME

AIAA Journal, 1963
5 Petrick, E. N. and Krauss, J. J., "The design and evaluation of perforated ion emitters" Final TR, Contract AF 33(657)-8638, performed for Aeronaut. Systems Div., U. S. Air Force, by Kelsey Hayes Co., Romulus, Mich. (September 15, 1963). 6 Winterbottom, W. L. and Hirth, J. P., "Diffusional contribution to the total flow from a knudsen cell," J. Chem.
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Unsteady flow separation on slip boundaries

Physics of Fluids, 2008
We derive analytic criteria for the location and angle of unsteady particle separation and reattachment in two-dimensional flows with free-slip boundary conditions. Our wall-based criteria show that, in general, fluid breakaway from the boundary takes place at locations different from either instantaneous or averaged stagnation points. Indeed, for time-
Lekien, Francois, Haller, George
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Atomistic simulations with slip boundary conditions

Physical Review B, 2001
Dynamical variables are incorporated into Parrinello-Rahman simulations that allow for slipping of the simulation cell relative to its periodic images above and below a specified plane. Equations of motion are derived that show the slip to be determined by the dynamical balance of an internal virial traction and an external glide force. Elements of the
J. V. Lill, Jeremy Q. Broughton
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Convection with Slip Boundary Conditions

2015
There is increasing interest in micro-electro-mechanical-systems (MEMS), and flow in microfluidic channels due to their applications in the electronics and related industries. In particular, at nanoscales there is increasing evidence that boundary conditions of slip type are needed rather than those of no-slip.
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Grain boundary slip in polycrystalline beryllium

Metal Science and Heat Treatment, 1975
1. Grain boundary slip was investigated in polycrystalline beryllium of commerical purity. It was found that ɛgb is directly proportional to the total deformation, i.e, ɛgb=γɛ∑. The value of γ varies in a complex manner with the deformation temperature. 2.
E. S. Karpov, I. I. Papirov, G. F. Tikhinskii   +2 more
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Dislocation boundaries and active slip systems

Acta Metallurgica et Materialia, 1995
Part of the dislocations which have participated in the plastic deformation of a polycrystalline metal are stored in dislocation boundaries in a two- or three-dimensional arrangement. The dislocations in such boundaries can be analysed by determining the misorientation between neighbouring crystallites and the boundary orientation.
J.A. Wert, Q. Liu, N. Hansen
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