AEROSOL-PARTICLE DEPOSITION IN AN OBSTRUCTED TURBULENT DUCT FLOW

A computational scheme for simulating aerosol particle dispersion and deposition in turbulent flows in passages with complex geometry is dev eloped. A thermodynamically consistent rate-dependent algebraic stress model is used to simulate the mean turbulent flow fields. The instant aneous turbulence fluctuation is simulated as a continuous Gaussian ra ndom field. The Brownian motion is modeled as a white noise process. T he particle equation of motion including the Stokes drag, Brownian and Saffman forces is used. The computational model predictions for parti cle deposition velocity in a turbulent channel flow are compared with the experimental data and earlier simulation results. Several digital simulations for aerosol particle transport and deposition in a duct wi th an obstructing block are performed. The corresponding capture effic iencies of rectangular and trapezoidal blocks for different particle S tokes number are evaluated and discussed. It is shown that the deposit ion rate decreases significantly as the shape of the obstruction becom es more streamlined.