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LBM, a useful tool for mesoscale modelling of single phase and multiphase flow – the variety of applications and approaches at Nottingham
This paper was presented at the 2nd Micro and Nano Flows Conference (MNF2009), which was held at Brunel University, West London, UK. The conference was organised by Brunel University and supported by the Institution of Mechanical Engineers, IPEM, the Italian Union of Thermofluid dynamics, the Process Intensification Network, HEXAG - the Heat Exchange Action Group and the Institute of Mathematics and its Applications.Giving an overview of Nottingham group’s recent progress on numerical modelling and
approaches in developing and applying the lattice Boltzmann method (LBM), the paper tries to demonstrate that the LBM is a useful tool for mesoscale modelling of single phase and multiphase flow. The variety of applications of the LBM modelling is reported, which include single phase fluid flow and heat transfer around or across rotational cylinder of curved boundary, two-phase flow in mixing layer, electroosmotically driven flow in thin liquid layer, bubbles/drops flow and coalescence in conventional channels and in
microchannels with confined boundary, liquid droplets in gas with relative large density ratio; viscous fingering phenomena of immiscible fluids displacement, and flow in porous media
Representation Class and Geometrical Invariants of Quantum States under Local Unitary Transformations
We investigate the equivalence of bipartite quantum mixed states under local
unitary transformations by introducing representation classes from a
geometrical approach. It is shown that two bipartite mixed states are
equivalent under local unitary transformations if and only if they have the
same representation class. Detailed examples are given on calculating
representation classes.Comment: 11 page
A physics-preserving pure streamfunction formulation and high-order compact solver with high-resolution for three-dimensional steady incompressible flows
Cultivo intercalar de milho seguido de caupi num plantio de dendê.
bitstream/item/40157/1/Circ-Tec-47-CPATU.pd
Hawking radiation of Dirac particles via tunneling from Kerr black hole
We investigated Dirac Particles' Hawking radiation from event horizon of Kerr
black hole in terms of the tunneling formalism. Applying WKB approximation to
the general covariant Dirac equation in Kerr spacetime background, we obtain
the tunneling probability for fermions and Hawking temperature of Kerr black
hole. The result obtained by taking the fermion tunneling into account is
consistent with the previous literatures.Comment: 7 pages, no figures, to appear in CQ
Measure representation and multifractal analysis of complete genomes
This paper introduces the notion of measure representation of DNA sequences.
Spectral analysis and multifractal analysis are then performed on the measure
representations of a large number of complete genomes. The main aim of this
paper is to discuss the multifractal property of the measure representation and
the classification of bacteria. From the measure representations and the values
of the spectra and related curves, it is concluded that these
complete genomes are not random sequences. In fact, spectral analyses performed
indicate that these measure representations considered as time series, exhibit
strong long-range correlation. For substrings with length K=8, the
spectra of all organisms studied are multifractal-like and sufficiently smooth
for the curves to be meaningful. The curves of all bacteria
resemble a classical phase transition at a critical point. But the 'analogous'
phase transitions of chromosomes of non-bacteria organisms are different. Apart
from Chromosome 1 of {\it C. elegans}, they exhibit the shape of double-peaked
specific heat function.Comment: 12 pages with 9 figures and 1 tabl
Galaxy infall kinematics as a test of modified gravity
Infrared modifications of General Relativity (GR) can be revealed by comparing the mass of galaxy clusters estimated from weak lensing to that from infall kinematics. We measure the 2D galaxy velocity distribution in the cluster infall region by applying the galaxy infall kinematics (GIK) model developed by Zu and Weinberg (2013) to two suites of f(R) and Galileon modified gravity simulations. Despite having distinct screening mechanisms, namely, the Chameleon and the Vainshtein effects, the f(R) and Galileon clusters exhibit very similar deviations in their GIK profiles from GR, with ~ 100-200 k/s enhancement in the characteristic infall velocity at r=5 Mpc/h and 50-100 km/s broadening in the radial and tangential velocity dispersions across the entire infall region, for clusters with mass ~ 10^{14} Msol/h at z=0.25. These deviations are detectable via the GIK reconstruction of the redshift--space cluster-galaxy cross-correlation function, xi_cg^s(r_p,r_\pi), which shows ~ 1-2 Mpc/h increase in the characteristic line-of-sight distance r_\pi^c at r_p<6 Mpc/h from GR predictions. With overlapping deep imaging and large redshift surveys in the future, we expect that the GIK modelling of xi_cg^s, in combination with the stacked weak lensing measurements, will provide powerful diagnostics of modified gravity theories and the origin of cosmic acceleration
Stellar Velocity Dispersion Measurements in High-Luminosity Quasar Hosts and Implications for the AGN Black Hole Mass Scale
We present new stellar velocity dispersion measurements for four luminous
quasars with the NIFS instrument and the ALTAIR laser guide star adaptive
optics system on the Gemini North 8-m telescope. Stellar velocity dispersion
measurements and measurements of the supermassive black hole masses in luminous
quasars are necessary to investigate the coevolution of black holes and
galaxies, trace the details of accretion, and probe the nature of feedback. We
find that higher-luminosity quasars with higher-mass black holes are not offset
with respect to the MBH-sigma relation exhibited by lower-luminosity AGNs with
lower-mass black holes, nor do we see correlations with galaxy morphology. As
part of this analysis, we have recalculated the virial products for the entire
sample of reverberation-mapped AGNs and used these data to redetermine the mean
virial factor hfi that places the reverberation data on the quiescent
M_BH-sigma relation. With our updated measurements and new additions to the AGN
sample, we obtain = 4.31 +/- 1.05, which is slightly lower than, but
consistent with, most previous determinations.Comment: Accepted for publication in ApJ. For a brief video highlighting the
results of this paper, see: http://www.youtube.com/watch?v=Mxx80aOVw1
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