The Experts below are selected from a list of 10563 Experts worldwide ranked by ideXlab platform

Y T Chew - One of the best experts on this subject based on the ideXlab platform.

  • development of an immersed boundary phase field lattice boltzmann method for neumann boundary condition to study contact line dynamics
    Journal of Computational Physics, 2013
    Co-Authors: J Y Shao, Y T Chew
    Abstract:

    The implementation of Neumann boundary condition in the framework of immersed boundary method (IBM) is presented in this paper to simulate contact line dynamics using a phase field-lattice Boltzmann method. Immersed boundary method [10] is known as an efficient algorithm for modelling fluid-solid interaction. Abundance of prominent works have been devoted to refine IBM [1,11,12]. However, they are mainly restricted to problems with Dirichlet boundary condition. Research that implements the Neumann boundary condition in IBM is very limited to the best of our knowledge. This deficiency significantly limits the application of IBM in computational fluid dynamics (CFD) since Physical phenomena associated with Neumann boundary conditions are extremely diverse. The difficulty is attributed to the fact that implementation of Neumann boundary condition is much more complex than that of Dirichlet boundary condition. In the present work, we initiate the first endeavour to implement Neumann boundary condition in IBM with assistance of its Physical interpretation rather than simple mathematical manipulation. Concretely speaking, rooted from Physical conservation law, the Neumann boundary condition is considered as contribution of flux from the boundary to its Relevant Physical Parameter in a control volume. Moreover, the link between the flux and its corresponding flow field variable is directly manipulated through the immersed boundary concept. In this way, the Neumann boundary conditions can be implemented in IBM. The developed method is applied together with phase field-lattice Boltzmann method to study contact line dynamics. The phase field method [27,39], which becomes increasingly popular in multiphase flow simulation, can efficiently capture complex interface topology and naturally resolve the contact line singularity. Meanwhile, the lattice Boltzmann method is known as an alternative to model fluid dynamics and holds good prospect to simulate multiphase flows with complex geometry [38]. In this context, the developed immersed boundary-phase field-LBM is verified in detail for both steady and unsteady contact line problems. Tests show that the proposed method can correctly reproduce both equilibrium results and dynamic process.

Caps Hervé - One of the best experts on this subject based on the ideXlab platform.

  • Locally induced laminar convection in liquid nitrogen and silicone oils.
    'Springer Science and Business Media LLC', 2016
    Co-Authors: Dubois Charles, Duchesne Alexis, Vanderheyden Benoît, Vanderbemden Philippe, Caps Hervé
    Abstract:

    We present an experimental study of a laminar convective phenomenon induced by a centimetric heater totally immersed in a liquid pool (Rayleigh number ranging from 10(4) to 10(7)). This local heating is observed to induce a laminar convection that differs from the classical Rayleigh-Benard cells created by heating the whole bottom of the fluid: the convection pattern is no more periodic. In order to obtain a complete map of the velocity field, we use Particle Image Velocimetry technique. The vertical velocity between the counter-rotating convective cells is used as the Relevant Physical Parameter to describe the phenomenon. The potential cooling applications of this problem lead us to choose liquid nitrogen as an experimental fluid. We thus compare the results obtained for various temperature gradients in liquid nitrogen with experiments performed at room temperature with silicone oils of various viscosities. The theoretical law for the maximal vertical velocity from classical Rayleigh-Benard experiments is adapted to the specific geometry investigated by using a new definition for the characteristic wavelength. This length is studied and appears to be dependent on the liquid properties. We finally obtain a remarkable agreement between theory and experimental data.Peer reviewe

  • Locally induced laminar convection in liquid nitrogen and silicone oils.
    'Springer Science and Business Media LLC', 2016
    Co-Authors: Dubois Charles, Duchesne Alexis, Vanderheyden Benoît, Vanderbemden Philippe, Caps Hervé
    Abstract:

    peer reviewedaudience: researcher, professionalWe present an experimental study of a laminar convective phenomenon induced by a centimetric heater totally immersed in a liquid pool (Rayleigh number ranging from 10(4) to 10(7)). This local heating is observed to induce a laminar convection that differs from the classical Rayleigh-Benard cells created by heating the whole bottom of the fluid: the convection pattern is no more periodic. In order to obtain a complete map of the velocity field, we use Particle Image Velocimetry technique. The vertical velocity between the counter-rotating convective cells is used as the Relevant Physical Parameter to describe the phenomenon. The potential cooling applications of this problem lead us to choose liquid nitrogen as an experimental fluid. We thus compare the results obtained for various temperature gradients in liquid nitrogen with experiments performed at room temperature with silicone oils of various viscosities. The theoretical law for the maximal vertical velocity from classical Rayleigh-Benard experiments is adapted to the specific geometry investigated by using a new definition for the characteristic wavelength. This length is studied and appears to be dependent on the liquid properties. We finally obtain a remarkable agreement between theory and experimental data

J Y Shao - One of the best experts on this subject based on the ideXlab platform.

  • development of an immersed boundary phase field lattice boltzmann method for neumann boundary condition to study contact line dynamics
    Journal of Computational Physics, 2013
    Co-Authors: J Y Shao, Y T Chew
    Abstract:

    The implementation of Neumann boundary condition in the framework of immersed boundary method (IBM) is presented in this paper to simulate contact line dynamics using a phase field-lattice Boltzmann method. Immersed boundary method [10] is known as an efficient algorithm for modelling fluid-solid interaction. Abundance of prominent works have been devoted to refine IBM [1,11,12]. However, they are mainly restricted to problems with Dirichlet boundary condition. Research that implements the Neumann boundary condition in IBM is very limited to the best of our knowledge. This deficiency significantly limits the application of IBM in computational fluid dynamics (CFD) since Physical phenomena associated with Neumann boundary conditions are extremely diverse. The difficulty is attributed to the fact that implementation of Neumann boundary condition is much more complex than that of Dirichlet boundary condition. In the present work, we initiate the first endeavour to implement Neumann boundary condition in IBM with assistance of its Physical interpretation rather than simple mathematical manipulation. Concretely speaking, rooted from Physical conservation law, the Neumann boundary condition is considered as contribution of flux from the boundary to its Relevant Physical Parameter in a control volume. Moreover, the link between the flux and its corresponding flow field variable is directly manipulated through the immersed boundary concept. In this way, the Neumann boundary conditions can be implemented in IBM. The developed method is applied together with phase field-lattice Boltzmann method to study contact line dynamics. The phase field method [27,39], which becomes increasingly popular in multiphase flow simulation, can efficiently capture complex interface topology and naturally resolve the contact line singularity. Meanwhile, the lattice Boltzmann method is known as an alternative to model fluid dynamics and holds good prospect to simulate multiphase flows with complex geometry [38]. In this context, the developed immersed boundary-phase field-LBM is verified in detail for both steady and unsteady contact line problems. Tests show that the proposed method can correctly reproduce both equilibrium results and dynamic process.

Dubois Charles - One of the best experts on this subject based on the ideXlab platform.

  • Locally induced laminar convection in liquid nitrogen and silicone oils.
    'Springer Science and Business Media LLC', 2016
    Co-Authors: Dubois Charles, Duchesne Alexis, Vanderheyden Benoît, Vanderbemden Philippe, Caps Hervé
    Abstract:

    We present an experimental study of a laminar convective phenomenon induced by a centimetric heater totally immersed in a liquid pool (Rayleigh number ranging from 10(4) to 10(7)). This local heating is observed to induce a laminar convection that differs from the classical Rayleigh-Benard cells created by heating the whole bottom of the fluid: the convection pattern is no more periodic. In order to obtain a complete map of the velocity field, we use Particle Image Velocimetry technique. The vertical velocity between the counter-rotating convective cells is used as the Relevant Physical Parameter to describe the phenomenon. The potential cooling applications of this problem lead us to choose liquid nitrogen as an experimental fluid. We thus compare the results obtained for various temperature gradients in liquid nitrogen with experiments performed at room temperature with silicone oils of various viscosities. The theoretical law for the maximal vertical velocity from classical Rayleigh-Benard experiments is adapted to the specific geometry investigated by using a new definition for the characteristic wavelength. This length is studied and appears to be dependent on the liquid properties. We finally obtain a remarkable agreement between theory and experimental data.Peer reviewe

  • Locally induced laminar convection in liquid nitrogen and silicone oils.
    'Springer Science and Business Media LLC', 2016
    Co-Authors: Dubois Charles, Duchesne Alexis, Vanderheyden Benoît, Vanderbemden Philippe, Caps Hervé
    Abstract:

    peer reviewedaudience: researcher, professionalWe present an experimental study of a laminar convective phenomenon induced by a centimetric heater totally immersed in a liquid pool (Rayleigh number ranging from 10(4) to 10(7)). This local heating is observed to induce a laminar convection that differs from the classical Rayleigh-Benard cells created by heating the whole bottom of the fluid: the convection pattern is no more periodic. In order to obtain a complete map of the velocity field, we use Particle Image Velocimetry technique. The vertical velocity between the counter-rotating convective cells is used as the Relevant Physical Parameter to describe the phenomenon. The potential cooling applications of this problem lead us to choose liquid nitrogen as an experimental fluid. We thus compare the results obtained for various temperature gradients in liquid nitrogen with experiments performed at room temperature with silicone oils of various viscosities. The theoretical law for the maximal vertical velocity from classical Rayleigh-Benard experiments is adapted to the specific geometry investigated by using a new definition for the characteristic wavelength. This length is studied and appears to be dependent on the liquid properties. We finally obtain a remarkable agreement between theory and experimental data

Duchesne Alexis - One of the best experts on this subject based on the ideXlab platform.

  • Locally induced laminar convection in liquid nitrogen and silicone oils.
    'Springer Science and Business Media LLC', 2016
    Co-Authors: Dubois Charles, Duchesne Alexis, Vanderheyden Benoît, Vanderbemden Philippe, Caps Hervé
    Abstract:

    We present an experimental study of a laminar convective phenomenon induced by a centimetric heater totally immersed in a liquid pool (Rayleigh number ranging from 10(4) to 10(7)). This local heating is observed to induce a laminar convection that differs from the classical Rayleigh-Benard cells created by heating the whole bottom of the fluid: the convection pattern is no more periodic. In order to obtain a complete map of the velocity field, we use Particle Image Velocimetry technique. The vertical velocity between the counter-rotating convective cells is used as the Relevant Physical Parameter to describe the phenomenon. The potential cooling applications of this problem lead us to choose liquid nitrogen as an experimental fluid. We thus compare the results obtained for various temperature gradients in liquid nitrogen with experiments performed at room temperature with silicone oils of various viscosities. The theoretical law for the maximal vertical velocity from classical Rayleigh-Benard experiments is adapted to the specific geometry investigated by using a new definition for the characteristic wavelength. This length is studied and appears to be dependent on the liquid properties. We finally obtain a remarkable agreement between theory and experimental data.Peer reviewe

  • Locally induced laminar convection in liquid nitrogen and silicone oils.
    'Springer Science and Business Media LLC', 2016
    Co-Authors: Dubois Charles, Duchesne Alexis, Vanderheyden Benoît, Vanderbemden Philippe, Caps Hervé
    Abstract:

    peer reviewedaudience: researcher, professionalWe present an experimental study of a laminar convective phenomenon induced by a centimetric heater totally immersed in a liquid pool (Rayleigh number ranging from 10(4) to 10(7)). This local heating is observed to induce a laminar convection that differs from the classical Rayleigh-Benard cells created by heating the whole bottom of the fluid: the convection pattern is no more periodic. In order to obtain a complete map of the velocity field, we use Particle Image Velocimetry technique. The vertical velocity between the counter-rotating convective cells is used as the Relevant Physical Parameter to describe the phenomenon. The potential cooling applications of this problem lead us to choose liquid nitrogen as an experimental fluid. We thus compare the results obtained for various temperature gradients in liquid nitrogen with experiments performed at room temperature with silicone oils of various viscosities. The theoretical law for the maximal vertical velocity from classical Rayleigh-Benard experiments is adapted to the specific geometry investigated by using a new definition for the characteristic wavelength. This length is studied and appears to be dependent on the liquid properties. We finally obtain a remarkable agreement between theory and experimental data