NT-87-25-3 -- Effect of Turbulence from Upwind Buildings on Dilution of Exhaust Gases ✓ Most Recent

The dilution of exhaust gases from building vents is caused by the dispersive effects of turbulence from flow patterns over the building itself and by turbulence that is carried downwind from nearby buildings. Under low wind nighttime conditions, much of the turbulence generated by upwind buildings may be damped by atmospheric temperature stability. Under these conditions, the absolute minimum dilution occurs, caused entirely by self-generated building turbulence. This study examines the effeqt of upwind turbulence by comparing wind tunnel simulations with varying upwind conditions. The results show that the turbulence carried from upwind buildings increases dilution from building-generated turbulence by factors of 2 to 10.

Units: SI