Thermophoretic deposition of aerosol particles in laminar mixed convection flow in a channel with two heated built-in square cylinders

In this study, the effect of thermophoresis on deposition of aerosol particles in laminar mixed convection flow in a channel with two built-in square cylinders was studied numerically. Continuity, momentum and energy equations were solved to determine the velocity and temperature profiles. The lagrangian approach was applied to obtain the particle phase behavior. The equation of particle motion was solved to determine the particle trajectory. Comparison between mixed and force convection flow shows the deposition in mixed flow regime is higher. The presence of heated square cylinders in the channel increased the temperature gradient and thermophoretic effect near the channel wall. On the other hand, presence of cylinders causes inertial impaction deposition on the channel walls. Thermophortic and inertia impaction are two dominant deposition mechanisms in the presence of heated square cylinders. The distance between cylinders is a parameter that influences the deposition of particles. It is seen that the maximum deposition occurs in distance which is four times bigger than length of cylinders. It is observed that by increasing Richardson number deposition of particles increases due to the effect of free convection.

کلیدواژه ها:

Thermophortic ، Channel flow ، Mixed convection ، Free convection ، Particle deposition