Assessment of a Chimney Jet Flowing Around an Obstacle

Abstract

A numerical modeling study was undertaken in order to examine the structure of the flow issued from a bent chimney around a parallelepiped obstacle. The main purpose of this work is to track the overall evolution of the flow and determine the thermal and mass transfer features that characterize the resulting flow field. We first validated the numerical model with experimental data. The experimental data are depicted by means of a particle image velocimetry technique. The numerical model is simulated by solving the mass, momentum, energy, and species equations. The finite-volume method is used, together with the second-order Reynolds stress model. A good level of agreement was achieved between the experimental data and numerical calculations. The comparison concerned both the mean and fluctuating dynamic features. Once validated, our model allowed the evaluation of the effect of different parameters on the heat and mass transfer features. These parameters consist of the velocity ratio (0.5, 1, and 1.6), the distance separating the chimney and the obstacle (100 mm and 200 mm), the height of the obstacle (50 mm, 90 mm, and 150 mm) and the orientation of the bent chimney (15°, 30°, and 45°). The evaluation of the effects of these different parameters has the ultimate purpose of determining the optimum conditions for the weakest concentration of pollutants.