Peristaltic particle transport using the lattice Boltzmann method

Abstract

Peristaltic transport refers to a class of internal fluid flows where the periodic deformation of flexible containing walls elicits a non-negligible fluid motion. It is a mechanism used to transport fluid and immersed solid particles in a tube or chan nel when it is ineffective or impossible to impose a favorable pressure gradient or desirous to avoid contact between the transported mixture and mechanical mov ing parts. Peristaltic transport occurs in many physiological situations and has myriad industrial applications. We focus our study on the peristaltic transport of a macroscopic particle in a two dimensional channel using the Lattice Boltzmann Method(LBM). We systematically investigate the effect of variation of the relevant dimensionless paJ'ameters of the system on the paJ·ticle transport. We find , among other results, a case where an increase of Reynolds number CaJl actually lead to a slight increase in particle transport, and a case where as the wall deformation•Author to whom correspondence should be addressed. Electronic mail: kconninl @jhu.edu 1 1 increases, the motion of the particle becomes non-negative only. VVe examine the particle behavior when the system exhibits the peculiar phenomenon of fluid tmp ping. Under these circumstances, the particle may itself become tmpped where it is subsequently transported at the wave speed, which is the ma.ximum possible transport in the absence of a favorable pressure gradient . Finally, we analyze how the particle presence affects stress, pressure, and dissipation in the fluid in hopes of determining preferred working conditions for peristaltic transport of shear-sensitive particles. We fiud that the levels of shear stress are most hazardous near the throat of the channel. We advise that shear-sensitive particles should be transported un der conditions where tmpping occurs as the particle is typically situated in a region of innocuous shear stress levels.

Investigating the relationships between peristaltic contraction and fluid transport in the human colon using Smoothed Particle Hydrodynamics

“…This recirculation zone will be important for transport and mixing. The identification of this flow structure is not new and fluid trapping (and the trapping of solid particles) inside similar recirculation zones has been observed in other peristaltic flow models that use prescribed wall shape and motions [27]. Inside the region where the walls are contracted we also see a strong jet of retrograde flow which extends just outside the region of the muscular contraction.…”

A model of Stokesian peristalsis and vesicle transport in a three-dimensional closed cavity

“…This seems to contradict the corresponding results presented here for an axially placed vesicle in an open tube, where we observe very little difference between the transport speeds of tracers and vesicles. However, Connington et al (2009) showed that the increased transport speed observed in Fauci (1992) was due to the periodic copy of the circular particle at every wavelength of the channel. When periodic channels with only one finite-sized particle per five or ten wavelengths were tracked, the transport speed did not increase with particle diameter (Connington et al, 2009).…”

“…However, Connington et al (2009) showed that the increased transport speed observed in Fauci (1992) was due to the periodic copy of the circular particle at every wavelength of the channel. When periodic channels with only one finite-sized particle per five or ten wavelengths were tracked, the transport speed did not increase with particle diameter (Connington et al, 2009). Again, we see the crucial dependence upon boundary conditions imposed at the tube ends.…”

“…Previous computational studies of finite-size particle transport in a two-dimensional periodic channel include an immersed boundary model by Fauci (1992), and a more recent lattice Boltzmann model by Connington et al (2009). Fauci (1992 found that an axially placed circular particle was transported in the direction of the peristaltic wave at a velocity much greater than a fluid tracer.…”

Numerical study of gravity-driven droplet displacement on a surface using the pseudopotential multiphase lattice Boltzmann model with high density ratio

“…The LBM has been successfully applied to a wide range of complex transport problems, such as porous flow [7], multiphase flow [13], particle flow [20] and reactive transport processes [21][22][23]. In the LB equation, fluid motion is represented by a set of particle distribution functions.…”