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On Oscillatory Instability in Convective Burning of Gas-Permeable Explosives

I. Brailovsky, M. Frankel, L. Kagan, G. Sivashinsky (2010)

Mathematical Modelling of Natural Phenomena

The experimentally known phenomenon of oscillatory instability in convective burning of porous explosives is discussed. A simple phenomenological model accounting for the ejection of unburned particles from the consolidated charge is formulated and analyzed. It is shown that the post-front hydraulic resistance induced by the ejected particles provides a mechanism for the oscillatory burning.

On some optimal control problems for the heat radiative transfer equation

Sandro Manservisi, Knut Heusermann (2010)

ESAIM: Control, Optimisation and Calculus of Variations

This paper is concerned with some optimal control problems for the Stefan-Boltzmann radiative transfer equation. The objective of the optimisation is to obtain a desired temperature profile on part of the domain by controlling the source or the shape of the domain. We present two problems with the same objective functional: an optimal control problem for the intensity and the position of the heat sources and an optimal shape design problem where the top surface is sought as control. The problems...

On the Caginalp system with dynamic boundary conditions and singular potentials

Laurence Cherfils, Alain Miranville (2009)

Applications of Mathematics

This article is devoted to the study of the Caginalp phase field system with dynamic boundary conditions and singular potentials. We first show that, for initial data in H 2 , the solutions are strictly separated from the singularities of the potential. This turns out to be our main argument in the proof of the existence and uniqueness of solutions. We then prove the existence of global attractors. In the last part of the article, we adapt well-known results concerning the Łojasiewicz inequality in...

On the importance of solid deformations in convection-dominated liquid/solid phase change of pure materials

Daniela Mansutti, Edoardo Bucchignani (2011)

Applications of Mathematics

We analyse the effect of the mechanical response of the solid phase during liquid/solid phase change by numerical simulation of a benchmark test based on the well-known and debated experiment of melting of a pure gallium slab counducted by Gau & Viskanta in 1986. The adopted mathematical model includes the description of the melt flow and of the solid phase deformations. Surprisingly the conclusion reached is that, even in this case of pure material, the contribution of the solid phase to the...

On the modeling of the transport of particles in turbulent flows

Thierry Goudon, Frédéric Poupaud (2004)

ESAIM: Mathematical Modelling and Numerical Analysis - Modélisation Mathématique et Analyse Numérique

We investigate different asymptotic regimes for Vlasov equations modeling the evolution of a cloud of particles in a turbulent flow. In one case we obtain a convection or a convection-diffusion effective equation on the concentration of particles. In the second case, the effective model relies on a Vlasov-Fokker-Planck equation.

On the modeling of the transport of particles in turbulent flows

Thierry Goudon, Frédéric Poupaud (2010)

ESAIM: Mathematical Modelling and Numerical Analysis

We investigate different asymptotic regimes for Vlasov equations modeling the evolution of a cloud of particles in a turbulent flow. In one case we obtain a convection or a convection-diffusion effective equation on the concentration of particles. In the second case, the effective model relies on a Vlasov-Fokker-Planck equation.

Currently displaying 21 – 40 of 62