8,740 research outputs found
Study of mechanical response in embossing of ceramic green substrate by micro-indentation
Micro-indentation test with a micro flat-end cone indenter was employed to
simulate micro embossing process and investigate the thermo-mechanical response
of ceramic green substrates. The laminated low temperature co-fired ceramic
green tapes were used as the testing material ; the correlations of indentation
depth versus applied force and applied stress at the temperatures of 25 degrees
C and 75degrees C were studied. The results showed that permanent indentation
cavities could be formed at temperatures ranging from 25 degrees C to 75
degrees C, and the depth of cavities created was applied force, temperature and
dwell time dependent. Creep occurred and made a larger contribution to the
plastic deformation at elevated temperatures and high peak loads. There was
instantaneous recovery during the unloading and retarded recovery in the first
day after indentation. There was no significant pile-up due to material flow
observed under compression at the temperature up to 75 degrees C. The plastic
deformation was the main cause for formation of cavity on the ceramic green
substrate under compression. The results can be used as a guideline for
embossing ceramic green substrates.Comment: Submitted on behalf of EDA Publishing Association
(http://irevues.inist.fr/handle/2042/16838
Galilean invariance of lattice Boltzmann models
It is well-known that the original lattice Boltzmann (LB) equation deviates
from the Navier-Stokes equations due to an unphysical velocity dependent
viscosity. This unphysical dependency violates the Galilean invariance and
limits the validation domain of the LB method to near incompressible flows. As
previously shown, recovery of correct transport phenomena in kinetic equations
depends on the higher hydrodynamic moments. In this Letter, we give specific
criteria for recovery of various transport coefficients. The Galilean
invariance of a general class of LB models is demonstrated via numerical
experiments
Recent results on charmed meson decays at BESIII
The BESIII Experiment at the Beijing Electron Positron Collider (BEPCII) has accumulated the world largest e+e− annihilation samples at 3.773 GeV with 2.93 fb−1 for D0(±) and 4.178 GeV with 3.19 fb−1 for D± s , which provide a clean background to study charmed meson decays. In this proceeding, we present the recent results of the study of D meson decays at BESII
Geometry Optimization of Self-Similar Transport Network
We optimize geometries of various self-similar transport networks using a three-step strategy based on the entransy theory. Using this optimization method, we obtained optimal relationships of geometric parameters of T-shape networks for fluid flow, heat conduction, convective heat transfer, and other transport phenomena. Some optimization results agree well with the existing theories or experimental data. The optimized transport network structure depends strongly on the optimization objective and the constraints, so that both the maximum heat transfer effect and minimum flow resistance cannot be satisfied at the same time
- …