The Experts below are selected from a list of 182343 Experts worldwide ranked by ideXlab platform

Tzyy-leng Horng - One of the best experts on this subject based on the ideXlab platform.

  • An immersed boundary method to solve fluid–solid interaction problems
    Computational Mechanics, 2009
    Co-Authors: Dedy Zulhidayat Noor, Ming-jyh Chern, Tzyy-leng Horng
    Abstract:

    We describe an immersed-boundary technique which is adopted from the direct-forcing method. A virtual force based on the rate of momentum changes of a solid body is added to the Navier–Stokes equations. The projection method is used to solve the Navier–Stokes equations. The second-order Adam–Bashford scheme is used for the temporal discretization while the diffusive and the convective terms are discretized using the second-order central difference and upwind schemes, respectively. Some benchmark problems for both stationary and moving solid object have been simulated to demonstrate the capability of the current method in handling fluid–solid Interactions.

  • an immersed boundary method to solve fluid solid interaction problems
    Computational Mechanics, 2009
    Co-Authors: Dedy Zulhidayat Noor, Ming-jyh Chern, Tzyy-leng Horng
    Abstract:

    We describe an immersed-boundary technique which is adopted from the direct-forcing method. A virtual force based on the rate of momentum changes of a solid body is added to the Navier–Stokes equations. The projection method is used to solve the Navier–Stokes equations. The second-order Adam–Bashford scheme is used for the temporal discretization while the diffusive and the convective terms are discretized using the second-order central difference and upwind schemes, respectively. Some benchmark problems for both stationary and moving solid object have been simulated to demonstrate the capability of the current method in handling fluid–solid Interactions.

Matthias Teschner - One of the best experts on this subject based on the ideXlab platform.

  • versatile surface tension and adhesion for sph fluids
    International Conference on Computer Graphics and Interactive Techniques, 2013
    Co-Authors: Nadir Akinci, Gizem Akinci, Matthias Teschner
    Abstract:

    Realistic handling of fluid-air and Fluid-Solid interfaces in SPH is a challenging problem. The main reason is that some important physical phenomena such as surface tension and adhesion emerge as a result of inter-molecular forces in a microscopic scale. This is different from scalar fields such as fluid pressure, which can be plausibly evaluated on a macroscopic scale using particles. Although there exist techniques to address this problem for some specific simulation scenarios, there does not yet exist a general approach to reproduce the variety of effects that emerge in reality from fluid-air and Fluid-Solid Interactions. In order to address this problem, we present a new surface tension force and a new adhesion force. Different from the existing work, our surface tension force can handle large surface tensions in a realistic way. This property lets our approach handle challenging real scenarios, such as water crown formation, various types of Fluid-Solid Interactions, and even droplet simulations. Furthermore, it prevents particle clustering at the free surface where inter-particle pressure forces are incorrect. Our adhesion force allows plausible two-way attraction of fluids and solids and can be used to model different wetting conditions. By using our forces, modeling surface tension and adhesion effects do not require involved techniques such as generating a ghost air phase or surface tracking. The forces are applied to the neighboring fluid-fluid and fluid-boundary particle pairs in a symmetric way, which satisfies momentum conservation. We demonstrate that combining both forces allows simulating a variety of interesting effects in a plausible way.

Dedy Zulhidayat Noor - One of the best experts on this subject based on the ideXlab platform.

  • An immersed boundary method to solve fluid–solid interaction problems
    Computational Mechanics, 2009
    Co-Authors: Dedy Zulhidayat Noor, Ming-jyh Chern, Tzyy-leng Horng
    Abstract:

    We describe an immersed-boundary technique which is adopted from the direct-forcing method. A virtual force based on the rate of momentum changes of a solid body is added to the Navier–Stokes equations. The projection method is used to solve the Navier–Stokes equations. The second-order Adam–Bashford scheme is used for the temporal discretization while the diffusive and the convective terms are discretized using the second-order central difference and upwind schemes, respectively. Some benchmark problems for both stationary and moving solid object have been simulated to demonstrate the capability of the current method in handling fluid–solid Interactions.

  • an immersed boundary method to solve fluid solid interaction problems
    Computational Mechanics, 2009
    Co-Authors: Dedy Zulhidayat Noor, Ming-jyh Chern, Tzyy-leng Horng
    Abstract:

    We describe an immersed-boundary technique which is adopted from the direct-forcing method. A virtual force based on the rate of momentum changes of a solid body is added to the Navier–Stokes equations. The projection method is used to solve the Navier–Stokes equations. The second-order Adam–Bashford scheme is used for the temporal discretization while the diffusive and the convective terms are discretized using the second-order central difference and upwind schemes, respectively. Some benchmark problems for both stationary and moving solid object have been simulated to demonstrate the capability of the current method in handling fluid–solid Interactions.

Paul Meakin - One of the best experts on this subject based on the ideXlab platform.

  • modeling of surface tension and contact angles with smoothed particle hydrodynamics
    Physical Review E, 2005
    Co-Authors: Alexandre M Tartakovsky, Paul Meakin
    Abstract:

    A two-dimensional numerical model based on smoothed particle hydrodynamics (SPH) was used to simulate unsaturated (multiphase) flow through fracture junctions. A combination of standard SPH equations with pairwise fluid-fluid and Fluid-Solid particle-particle Interactions allowed surface tension and three-phase contact dynamics to be simulated. The model was validated by calculating the surface tension in four different ways: (i) from small-amplitude oscillations of fluid drops, (ii) from the dependence of the capillary pressure on drop radius, (iii) from capillary rise simulations, and (iv) from the behavior of a fluid drop confined between parallel walls under the influence of gravity. All four simulations led to consistent values for the surface tension. The dependence of receding and advancing contact angles on droplet velocity was studied. Incorporation of surface tension and Fluid-Solid Interactions allowed unsaturated flow through fracture junctions to be realistically simulated, and the simulation results compare well with the laboratory experiments of Dragila and Weisbrod.

Kentaro Umeki - One of the best experts on this subject based on the ideXlab platform.

  • The effect of Stefan flow on the drag coefficient of spherical particles in a gas flow
    International Journal of Multiphase Flow, 2019
    Co-Authors: Thamali R. Jayawickrama, Nils Erland L Haugen, Matthâus Ulrich Bäbler, Muhammad Aqib Chishty, Kentaro Umeki
    Abstract:

    Abstract Particle laden flows with reactive particles are common in industrial applications. Chemical reactions inside the particle can generate a Stefan flow that affects heat, mass and momentum transfer between the particle and the bulk flow. This study aims at investigating the effect of Stefan flow on the drag coefficient of a spherical particle immersed in a uniform flow under isothermal conditions. Fully resolved simulations were carried out for particle Reynolds numbers ranging from 0.2 to 14 and Stefan flow Reynolds numbers from ( − 1 ) to 3, using the immersed boundary method for treating Fluid-Solid Interactions. Results showed that the drag coefficient decreased with an increase of the outward Stefan flow. The main reason was the change in viscous force by the expansion of the boundary layer surrounding the particle. A simple model was developed based on this physical interpretation. With only one fitting parameter, the performance of the model to describe the simulation data were comparable to previous empirical models.