Effects of traffic-generated turbulence on near-field dispersion

Abstract Data from the General Motors dispersion experiment are used to assess the characteristics of the traffic-generated turbulence and its effects on the dispersion process near roadways. The evaluation of the bulk statistics and spectra allowed the magnitude and extent of wake turbulence in the horizontal and vertical directions to be identified. Differences are noted in the dependence of the traffic influence on the wind speed for cases of parallel and perpendicular orientations to the roadway. The increase of spectral energy in the high frequency range due to the presence of traffic-generated eddies is used to determine the length scales of the eddies. These, in turn, are used to estimate the-traffic components of the eddy diffusivities and dispersion parameters which can be incorporated into the diffusion models.