Theoretical and Numerical Predictions of Two- dimensional Aaberg Slot Exhaust Hoods

摘要

Theoretical and computational fluid dynamical techniques are employed to predict the two- dimensional turbulent air flows which are created by an Aaberg slot exhaust hood, which is reinforced by a two-dimensional wall jet flow. The aim of the two-dimensional model is to numerically reveal the characteristics of the air flow in the central plane of the Aaberg workbench. A further development of the potential model is through the inclusion of the finite slot. We have found that the numerical results for the streamlines and the lines of constant speed produced by the potential flow model are in good agreement with those obtained when using the full turbulent flow model and the air velocity distribution predicted by both the potential and turbulent models agree very well with all the available experimental data. The comparison between the potential and the turbulent models reveals that the potential model has the advantage over the turbulent model in that there is much less uncertainty in the results obtained due to the more accurate specification of the boundary conditions on the open boundaries at large distances from the hood.