Combined single domain and subdomain BEM for 3D laminar viscous flow

Ravnik, Jure; Škerget, L.; Žunič, Zoran

doi:10.1016/j.enganabound.2008.06.006

Cited by 41 publications

(34 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We consider viscous fluid flow in the laminar flow regime. The velocity-vorticity formulation of Navier-Stokes equations is solved using the Boundary-Domain Integral Method [1]. A combination of sub-domain and single domain technique is used.…”

Section: Problem Formulationmentioning

confidence: 99%

Numerical simulation of particles movement in cellular flows under the influence of magnetic forces

Hriberšek

Steinmann

Ravnik

et al. 2011

Proc Appl Math and Mech

View full text Add to dashboard Cite

A numerical model of particle motion in fluid flow under the influence of hydrodynamic and magnetic forces is presented. As computational tool, a flow solver based on the Boundary Element Method is used. The Euler-Lagrange formulation of multiphase flow is considered. In the case of a particle with a magnetic moment in a nonuniform external magnetic field, the Kelvin body force acts on a single particle. The derived Lagrangian particle tracking algorithm is used for simulation of dilute suspensions of particles in viscous flows taking into account gravity, buoyancy, drag, pressure gradient, added mass and magnetophoretic force. As a benchmark test case the magnetite particle motion in cellular flow field of water is computed with and without the action of the magnetic force. The effect of the Kelvin force on particle motion and separation from the main flow is studied for a predefined magnetic field and different values of magnetic flux density. Problem formulationIn order to accurately describe hydrodynamics of flows with particles in the context of Euler-Lagrangian formulation, the computationally most affordable approach is the description of a particle as a rigid sphere, that interacts with the fluid phase. In order to capture the particle response to fluid flow structures, a full one-way coupling approach is implemented. We consider viscous fluid flow in the laminar flow regime. The velocity-vorticity formulation of Navier-Stokes equations is solved using the Boundary-Domain Integral Method [1]. A combination of sub-domain and single domain technique is used. Incompressible viscous Newtonian fluid with constant material properties is considered. The fluid flow is governed by the kinematics equationwhich links the velocity and vorticity fields for every point in space and time. The kinetic aspect of fluid movement is governed by the vorticity transport equation, written in non-dimensional form:with the Reynolds number denoted by Re.The system of equations (1) and (2) is solved in a nonlinear loop of three steps. First, the boundary vorticity values are calculated by solving the kinematics equation with the help of a single domain BEM. Second, the calculation of the domain velocity values is achieved by solving the kinematics equation with a subdomain BEM and finally, the vorticity transport equation for domain vorticity values using the boundary values from the solution of the kinematics equation is solved by a subdomain BEM.In the case of a particle with a magnetic moment in a nonuniform external magnetic field, the Kelvin body force acts on a single particle. The established model for the magnetic force on a single particle reads as:with µ 0 the magnetic permeability in vacuum, (χ p − χ f ) magnetic susceptibility between the particle and the fluid and V p particle volume. The force on a particle is proportional to the the strength of magnetic field and the field gradient. Lagrangian particle trackingNewton's law for a particle states the balance of forces, which are assumed to be linearly additive. The f...

show abstract

Section: Problem Formulationmentioning

confidence: 99%

Numerical simulation of particles movement in cellular flows under the influence of magnetic forces

Hriberšek

Steinmann

Ravnik

et al. 2011

Proc Appl Math and Mech

View full text Add to dashboard Cite

show abstract

“…The solver requires a large number of iterations in order to converge to a predefined convergence criteria . The original algorithm, as proposed by Ravnik et al [7], uses a constant convergence criteria. Value, which is 10 times less than the required RMS criteria err was usually used, i.e.…”

Section: Acceleration Of Computationmentioning

confidence: 99%

Simulation of flow of nanofluids by BEM

Ravnik¹,

Škerget²

2010

Boundary Elements and Other Mesh Reduction Methods XXXII

Self Cite

View full text Add to dashboard Cite

Heat transfer is one of the major engineering problems, which has to be addressed when progress is made in engineering technology. Low thermal conductivity of fluids such as water or oil, led to the introduction of nanofluids -stable suspensions of nanosized particles in base fluid. Nanofluids have very high thermal conductivities at very low nanoparticle concentrations and are able to substantially increase heat transfer.Numerical solver for simulation of flow and heat transfer of nanofluids was developed using Boundary Element Method. Velocity-vorticity formulation of Navier-Stokes equations is proposed for nanofluids and solved by a combination of single domain and sub-domain boundary element method. The developed solver was used to simulate three-dimensional natural convection of nanofluids. Results of simulations show that a substantial heat transfer enhancement can be observed and attributed to the usage of nanofluids. We observed that the nanofluid particle volume fraction also plays in important role increasing the volume fraction increases the heat transfer for all Rayleigh number values considered.

show abstract

“…In our work, as a starting point, the earlier work by Ravnik et al [4] was chosen, where a 2D flow simulation was coupled with an explicit Lagrangian particle tracking algorithm. The flow algorithm was extended to a 3D geometry in Ravnik et al [2] and in this work coupling with particle tracking is presented.…”

Section: Introductionmentioning

confidence: 99%

“…The method is based on the velocity-vorticity formulation of Navier-Stokes equations in Eulerian framework coupled with a Lagrangian particle tracking algorithm. A combined single domain and domain decomposition approach is employed to reduce the computational and memory requirements of the algorithm, [2,3]. Efficient algorithms for Lagrangian particle tracking in fluid flow are an ongoing research topic.…”

Section: Introductionmentioning

confidence: 99%

Separation of magnetic particles in channel flows by BEM

Ravnik

Hriberšek

Vogel

et al. 2012

Proc Appl Math and Mech

View full text Add to dashboard Cite

In-line separation of suspensions can become difficult in case of particles with comparable values of densities. For flows in micro devices in such cases gravitational settling is inefficient, and other separation techniques must be applied. In case of magneto active particles, the action of Kelvin magnetic force in a non-uniform magnetic field could be used in order to achieve a higher degree of particles separation. The contribution therefore deals with Euler-Lagrangian formulation of dilute two-phase flows. The Boundary element based computational algorithm solves the incompressible Navier-Stokes equations written in velocity-vorticity formulation. The non-uniform magnetic field is defined analytically for the case of a set of long thin wires. The particle trajectories are computed by applying the 4th order Runge-Kutta method. The computed test case consists of a narrow channel with laminar flow of suspension under Re = 1 − 10. Particle trajectories under the influence of a non-uniform magnetic field are computed for the case of magnetite and aluminium particles suspended in water. The efficiency of separation on basis of particle trajectories for different values of Re number and magnetic field strength is performed, clearly indicating superior separation of magneto active particles.

show abstract

Combined single domain and subdomain BEM for 3D laminar viscous flow

Cited by 41 publications

References 17 publications

Numerical simulation of particles movement in cellular flows under the influence of magnetic forces

Numerical simulation of particles movement in cellular flows under the influence of magnetic forces

Simulation of flow of nanofluids by BEM

Separation of magnetic particles in channel flows by BEM

Contact Info

Product

Resources

About