|
Research Interests:
My research interests are centered on kinetic theory for granular flows,
multiphase flows, computational fluid dynamics, and thermodynamics. In
addition, I have pursued interests in mathematical modeling of industrial
applications and nonlinear dynamics.
Research Summary:
Flows of polydisperse particles are common in variety
of industrial applications such as catalytic cracking, fluidized bed
applications for power production, mixing of pharmaceutical powders etc.
The analogy between rapidly flowing granular materials and some of the
more usual states of matter such as gases and liquids have been developed
over a period of several decades using kinetic theory. The kinetic theory
concepts have been extended to granular flows by taking into account the
dissipation due to inelastic collisions between the particles. For
monodisperse systems, kinetic theories have been successful in predicting
not only rapid granular flows but have also been incorporated into
gas-solid systems. In the past, kinetic theories have also been extended
to binary and ternary mixtures by assuming either Maxwellian velocity
distribution or an equipartition of energy. However, the presence of non-Maxwellian
velocity distribution in granular flows [1], and the presence and impact
of non-equipartition of energy between unlike particles [2, 3] have been
widely established using experiments and molecular dynamics (MD)
simulations.
Recently, a kinetic theory for s- component mixture
of inelastic, smooth hard disks (2D) and spheres (3D) has been derived
based on revised Enskog theory [4, 5]. This theory rigorously incorporates
the non-Maxwellian and non-equipartition effects, is applicable to wide
range of restitution coefficients, and is applicable to both dilute and
(moderately) dense flows. My research work will initially focus on the
verification of the new polydisperse kinetic theory. In particular, the
transport coefficients derived for the new theory will be compared with
existing theories derived using similar assumptions for monodisperse and
binary mixtures. In addition a suite of applicable verification tests will
be performed on the polydisperse transport coefficients. By taking the
method of moments approach, a representation of continuous particle size
distribution (PSD) will then be attempted using these transport
coefficients. Subsequently, the polydisperse kinetic theory will be
incorporated into Multiphase Flow with Interphase eXchanges (MFIX). The
numerical predictions obtained from MFIX will be validated by comparing
with experimental and MD results for fluidized bed systems.
[1] W. Losert, D.G.W. Cooper, J. Delour, A. Kudrolli, and J.P. Gollub,
Chaos 9, 682
(1999).
[2] R. D Wildman, and D. J.
Parker, Phys. Rev. Lett. 88,
064301 (2002).
[3] J. E. Galvin, S. R. Dahl, and C. M. Hrenya, J.
Fluid Mech. 528, 207 (2005).
[4] V. Garzó,
J. W. Dufty, and C. M. Hrenya, Phys. Rev. E. 76,
031303 (2007).
[5] V. Garzó,
C. M. Hrenya, J. W. Dufty, Phys. Rev. E. 76,
031304 (2007).
|
