Precipitation, deposition and sedimentation of particles in fluid flow
Y. Farjoun (Dept of Mathematics, MIT, USA) and L.L. Bonilla (G. Millán Institute, Universidad Carlos III, Leganés, Spain)
In many industrial processes, particles transported by gas flows may deposit on confining walls due to different mechanisms. Often times, heterogeneous condensation of vapors on particles transported by the flow or homogeneous condensation of vapors occurs and the resulting droplets move towards cold walls. The inertia of larger particles carried by turbulent flows may also be important in deposition processes. Examples include vapor deposition from combustion gases, fouling and corrosion in biofuel plants, chemical vapor deposition, vapor condensation and aerosols capture by cold plates or rejection by hot ones, deposition of particles in the lungs during breathing, etc.
In this minisymposium, several important examples of deposition processes will be presented, modeled and their governing equations will be analyzed and solved numerically. The talks by Y. Farjoun and J. Neu will consider condensation of dilute vapors mixed with a carrier gas in boundary layer flow near a cold wall. Heterogeneous condensation of vapors on small particles mixed with a carrier gas and their motion by thermophoresis to the wall will be analyzed by singular perturbation methods by J. Neu (joint work with L.L. Bonilla and A. Carpio). Homogeneous condensation and thermophoretic motion towards the cold wall will be studied by novel asymptotic methods by Y. Farjoun. The talks by P. Garcia-Ybarra (joint work with J.L. Castillo) and M. Uhlmann consider the cases of deposition and sedimentation of larger particles in turbulent flows. Garcia-Ybarra will study the limit of weak Brownian
diffusion and small inertia of the particles and typify the deposition characteristics in terms of a particle Peclet number, whereas Uhlmann will use direct numerical simulation to study sedimentation of particles in turbulent flows in the gravitational field.