Record Display for the EPA National Library Catalog


Main Title Turbulent Diffusion Behind Vehicles: Experimentally Determined Turbulence Mixing Parameters.
Author Eskridge, R. E. ; Rao, S. T. ;
CORP Author Environmental Protection Agency, Research Triangle Park, NC. Atmospheric Sciences Research Lab.;New York State Dept. of Environmental Conservation, Albany.
Year Published 1986
Report Number EPA/600/J-86/385;
Stock Number PB87-208690
Additional Subjects Automobiles ; Exhaust emissions ; Wind tunnel models ; Air pollution ; Wakes ; Eddies ; Ground vehicles ; Turbulent diffusion ; Automobile exhaust ; ROADWAY model
Library Call Number Additional Info Location Last
NTIS  PB87-208690 Some EPA libraries have a fiche copy filed under the call number shown. 07/26/2022
Collation 12p
The wake of a moving vehicle was simulated using a specially constructed wind tunnel with a moving floor. A 'blocked-shaped' model vehicle was fixed in position over the test-section floor while the floor moved at the freestream air speed to produce a uniform, shear-free, approach flow. This simulates an automobile traveling along a straight highway under calm atmospheric conditions. Vertical and lateral profiles of tracer gas concentration were obtained in the wake. Profiles were taken at distances of 30, 45, and 60 model heights downwind. The equations describing the wake theory were solved numerically to determine the 'best' turbulence scale lengths by using a wind tunnel taken at 30 model heights downwind as the inflow boundary condition and comparing the numerical computation made at 60 heights downwind to the wind tunnel data taken at this location. It was found that the 'best' scale lengths were the vehicle width along and across the wake, and height above the surface in the vertical directions, respectively. (Copyright (c) Atmospheric Environment Vol. 20, No. 5, pp. 851-860, 1986.)