Modeling and simulation of forest fire propagation
Mixture thermodynamics
Thermodynamics, Numerical Waves, Interfaces, Combustion Team
Présentation
The TONIC team is developing an activity of modeling of strongly multi-scale phenomena. It covers in particular multiphase and/or reactive flows, from the scale of the isolated injector (a few mm) to the scale of a fully developed forest fire (several hectares).
Adapted numerical methods are developed in parallel, in particular for soil imaging (detection of slicks by acoustic analysis), or for the modeling of radiative transfers.
In parallel to these multi-scale developments, analytical work is carried out to support the construction of models. An important research effort is devoted to the modeling of the thermodynamics of multiphase mixtures (thermochemical equilibrium calculations, complex thermodynamic closures), or to the development of reduced kinetic models for combustion.
équipe Thermodynamiques, Ondes, Numérique, Interfaces et Combustion
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Dernières publications de l'équipe
2022
Mostafa Taha, Song Zhao, Aymeric Lamorlette, Jean-Louis Consalvi, Pierre Boivin. Lattice-Boltzmann modeling of buoyancy-driven turbulent flows. Physics of Fluids, American Institute of Physics, 2022, ⟨10.1063/5.0088409⟩. ⟨hal-03661928⟩ Plus de détails...
The pressure-based hybrid lattice-Boltzmann method presented by Farag & al (Phys. Fluids 2020) is assessed for the simulation of buoyancy driven flows. The model is first validated on Rayleigh-Benard and Rayleigh-Taylor two-dimensional cases. A large-eddy simulation of a turbulent forced plume is then carried out, and results are validated against experiments. A good overall agreement is obtained, both for mean and fluctuations quantities, as well as global entertainment. The self-similarity character of the plume in the far-field is also recovered.
Mostafa Taha, Song Zhao, Aymeric Lamorlette, Jean-Louis Consalvi, Pierre Boivin. Lattice-Boltzmann modeling of buoyancy-driven turbulent flows. Physics of Fluids, American Institute of Physics, 2022, ⟨10.1063/5.0088409⟩. ⟨hal-03661928⟩
Karthik Bhairapurada, Bruno Denet, Pierre Boivin. A Lattice-Boltzmann study of premixed flames thermo-acoustic instabilities. Combustion and Flame, Elsevier, 2022, 240, pp.112049. ⟨hal-03582162⟩ Plus de détails...
We present possibly for the first time Lattice-Boltzmann numerical simulations of thermo-acoustic instabilities of premixed flames. We study flames interacting with an imposed acoustic field where flames submitted to a parametric instability can be observed, as well as plane flames re-stabilized by the acoustic forcing. Self-induced thermo-acoustic oscillations of flames propagating in narrow channels are also studied, indicating an unexpected dependency with the channel width. For both excited and self-excited flames, results confirm that Lattice-Boltzmann method can capture the complex coupling between flame dynamics and acoustics.
Karthik Bhairapurada, Bruno Denet, Pierre Boivin. A Lattice-Boltzmann study of premixed flames thermo-acoustic instabilities. Combustion and Flame, Elsevier, 2022, 240, pp.112049. ⟨hal-03582162⟩
Housseyn Smahi, Djilali Ameur, Joanna Dib, Isabelle Raspo. On the modeling and simulation of coupled adsorption and thermosolutal convection in supercritical carbon dioxide. Journal of Engineering and Applied Science, 2022, 69 (1), pp.5. ⟨10.1186/s44147-021-00054-4⟩. ⟨hal-03567395⟩ Plus de détails...
Abstract In this paper, we present a numerical study along with an exhaustive adsorption investigation in a binary dilute mixture model nearby the solvent’s critical point in a configuration relevant for soil remediation. By means of this model, mass and heat transfer efficiency were qualitatively and quantitatively discussed through this work. The convergence of the solution was evaluated on the values of the Nusselt and Sherwood numbers. The results reveal intense convection expanding into the cavity close to the critical point, thus enabling homogeneous adsorption of the solute. Moreover, the mass fraction perturbation isolines exhibit the existence, along the adsorbent plate, of a thin boundary layer which becomes thinner when approaching the critical point.
Housseyn Smahi, Djilali Ameur, Joanna Dib, Isabelle Raspo. On the modeling and simulation of coupled adsorption and thermosolutal convection in supercritical carbon dioxide. Journal of Engineering and Applied Science, 2022, 69 (1), pp.5. ⟨10.1186/s44147-021-00054-4⟩. ⟨hal-03567395⟩
Journal: Journal of Engineering and Applied Science
Gauthier Wissocq, Thomas Coratger, Gabriel Farag, Song Zhao, Pierre Boivin, et al.. Restoring the conservativity of characteristic-based segregated models: application to the hybrid lattice Boltzmann method. Physics of Fluids, American Institute of Physics, 2022, 34 (4), pp.046102. ⟨10.1063/5.0083377⟩. ⟨hal-03627520⟩ Plus de détails...
A general methodology is introduced to build conservative numerical models for fluid simulations based on segregated schemes, where mass, momentum and energy equations are solved by different methods. It is here especially designed for developing new numerical discretizations of the total energy equation, adapted to a thermal coupling with the lattice Boltzmann method (LBM). The proposed methodology is based on a linear equivalence with standard discretizations of the entropy equation, which, as a characteristic variable of the Euler system, allows efficiently decoupling the energy equation with the LBM. To this extent, any LBM scheme is equivalently written under a finite-volume formulation involving fluxes, which are further included in the total energy equation as numerical corrections. The viscous heat production is implicitly considered thanks to the knowledge of the LBM momentum flux. Three models are subsequently derived: a first-order upwind, a Lax-Wendroff and a third-order Godunov-type schemes. They are assessed on standard academic test cases: a Couette flow, entropy spot and vortex convections, a Sod shock tube, several two-dimensional Riemann problems and a shock-vortex interaction. Three key features are then exhibited: 1) the models are conservative by construction, recovering correct jump relations across shock waves, 2) the stability and accuracy of entropy modes can be explicitly controlled, 3) the low dissipation of the LBM for isentropic phenomena is preserved.
Gauthier Wissocq, Thomas Coratger, Gabriel Farag, Song Zhao, Pierre Boivin, et al.. Restoring the conservativity of characteristic-based segregated models: application to the hybrid lattice Boltzmann method. Physics of Fluids, American Institute of Physics, 2022, 34 (4), pp.046102. ⟨10.1063/5.0083377⟩. ⟨hal-03627520⟩
Nicolas Godinaud, Pierre Boivin, Pierre Freton, Jean-Jacques Gonzalez, Frédéric Camy-Peyret. Development of a new OpenFOAM solver for plasma cutting modelling. Computers and Fluids, Elsevier, In press, ⟨10.1016/j.compfluid.2022.105479⟩. ⟨hal-03661919⟩ Plus de détails...
A new OpenFOAM solver is presented, for the simulation of plasma cutting torches. The mathematical model that is introduced is based on the compressible Navier-Stokes equations coupled via source terms to the electric current conservation equation. Due to the conservative and hyperbolic nature of the model, a Godunov-type scheme is used for the first time in the context of plasma cutting simulation. The numerical method consists of a second-order Total Variation Diminishing (TVD) integration with flux Harten-Lax-van Leer-Contact (HLLC) Riemann solver for the flow conservation equations, coupled with a Laplace solver for the current conservation equation. An efficient formulation for the equation of state, accurately taking into account the plasma properties, is also presented. The solver is validated through a set of canonical test cases (shock tubes and 2D Riemann problems) and it is used to simulate a three-dimensional plasma cutting torch. Good agreement is found with the literature, with an improvement in the ability to deal with the shocks occurring during plasma cutting.
Nicolas Godinaud, Pierre Boivin, Pierre Freton, Jean-Jacques Gonzalez, Frédéric Camy-Peyret. Development of a new OpenFOAM solver for plasma cutting modelling. Computers and Fluids, Elsevier, In press, ⟨10.1016/j.compfluid.2022.105479⟩. ⟨hal-03661919⟩
Février 2022
- Lattice-Boltzmann methods for compressible flows / PhD defense Gabriel Farag
Doctorant : Fabriel FARAG
Date de soutenance : le 4 février 2022 à 14h00 ; Amphi 3 Centrale Marseille
Abstract : Since the late 1970's, computational fluid dynamics solvers became essentials due to increasingly complex applications requiring fluid solutions. The small scales necessary for industrial applications often need a very fine grid or very small timestep. This dramatically increases the computational cost of nowadays simulations. To design more computationally efficient solvers, a popular approach is to use Lattice-Boltzmann methods. Originating from the kinetic theory of gases, this method have gained a tremendous popularity among fluid dynamicists due to its cheap and easily implemented collide & stream algorithm. However, its intrinsic assumptions confines classical Lattice-Boltzmann solvers to weakly compressible flows. Yet, some compressible models have been proposed. The purpose of this manuscript is to improve the robustness as well as accuracy of compressible Lattice-Boltzmann models. To this end, the Lattice-Boltzmann method is fully reinterpreted as a numerical scheme. This allows a straightforward and parsimonious derivation of the equivalent Navier-Stokes-Fourier system using the sole assumption of a negligible timestep. Using this formalism, the order of accuracy is shown to depend on the collision kernel, as well as the mechanical constitutive model. Various models are investigated and we show that the Knudsen number is not the sole parameter controlling the consistency with the Navier-Stokes-Fourier model. Additionally, capabilities of the entropy equation to model low supersonic flows is explained through standard shock wave theory arguments. A MUSCL-Hancock scheme is employed to discretize the entropy equation and improve both stability and accuracy compared to previous schemes. Equipped with this new formalism, a compressible pressure-based model is proposed and validated on various supersonic test cases. Then, we unify all compressible models proposed by our group under a single formalism and investigate the differences and optimal choices for the various degrees of freedom of our family of models. Finally, this unified model is validated on high supersonic smooth flows and low supersonic shocked flows.
Jury
Directeur de these M. Pierre BOIVIN CNRS / M2P2
CoDirecteur de these M. Guillaume CHIAVASSA Centrale Marseille
