Numerical prediction of particle transport passed through ventilator by CFD with Lagrangian method

The use of CFD technique for predicting the properties of airflow fields and particle movement is effective to carry out parametric study intended for a wide range of particle sizes. In this study, particle dispersions due to turbulent flow and thermophoretic effect were analyzed for a simplified ventilator model. Numerical results that comprise a classification of particle motion, temperature difference and particle diameter were reported. The residence time of particles in the ventilator was confirmed to depend on temperature differences and particle sizes under the condition of constant supply inlet velocity. Large particles (100 μm) were strongly affected by gravitational force and settling to the inlet opening located lower part of the ventilator while smaller particles (10 μm) tended to follow the convective air streamlines. Particle removal by gravitational settling has possibilities by optimizing the flow path and velocity in the ventilator as functions of the target particle size.