We study the hydrodynamic forces acting on a fixed particle close to a corrugated wall experiencing tangential fluid flow, using the lattice Boltzmann method. To carry out a fundamental analysis, a single two-dimensional circular particle near a sinusoidal wall is selected as a case study. The influence of the particle distance from the wall, the particle Reynolds number, corrugation amplitude, and downstream particle position (relative to a corrugation-peak) on the drag, lift and torque acting on the particle are investigated. Our simulations reveal that the hydrodynamic forces change significantly by changing the particle distance from the wall. Even the direction of forces and torque may change, depending on the distance from the wall, downstream particle position and Re_p number. We find an increase in magnitude of forces and torque by increasing the corrugation amplitude of the wall.

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In this paper, the lattice Boltzmann method is applied to investigate the effects of uniform vertical magnetic field on thermo-hydrodynamics of nanofluid in a partially porous channel. Cu-water nanofluid with constant pressure gradient is forced to flow into the channel while the top wall is heated by constant heat flux and bottom wavy wall of the channel is insulated against heat. The porous media is modeled using the Brinkman–Forchheimer model. Good agreements with the previous results verify that the selected numerical method is a capable method for simulating magnetic fluids in a porous media. The effects of active parameters, i.e. solid volume fraction of nanoparticles, pressure gradient, magnetic field and permeability of the porous layer, on thermo-hydrodynamics of flow are examined. The results reveal that the Nusselt number is an increasing function of nanoparticle volume fraction, Hartmann number, pressure gradient and Darcy number, although the effect of Darcy numbers and pressure gradient on the temperature profile are more noticeable than others.

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In this paper, the thermo-hydrodynamics of Al2O3-water nanofluid in a wavy U-turn channel with hot walls is numerically investigated by means of lattice Boltzmann modeling. At first, the numerical technique is validated by simulating fluid flow in a (non-)wavy straight channel. Then, the effects of various active parameters, e.g. pressure gradient in the channel, nanoparticles volume fraction, and number of sinusoidal waves along the channel, on the flow field and heat transfer is studied. Furthermore, the thermal–hydraulic performance factor is determined to investigate whether heat transfer enhancement outweighs the greater frictional losses caused by both complex wavy wall geometry and nanoparticles. The results show that the heat transfer rises by increasing pressure gradient in the channel while drops by increasing number of waves. Also, the effect of nanoparticles volume fraction on dimensionless Nusselt number becomes more pronounced at higher pressure gradients. The results indicate that the thermal–hydraulic performance factor grows by increasing nanoparticles volume fraction or decreasing the number of waves.@en