caa a22 4500 47577762X CHVBK 20180406123635.0 cr unu---uuuuu 170329e20000601xx s 000 0 eng 10.1023/A:1002613403385 doi (NATIONALLICENCE)springer-10.1023/A:1002613403385 On The Influence Of The Eulerian Velocity PDF Closure On The Eddy Diffusion Coefficient [Elektronische Daten] [A. Maurizi, S. Lorenzani] The flux-gradient model, often used to describe turbulent dispersion, implicitly defines an eddy diffusion coefficient K that is known to be related to the Eulerian probability density function (pdf) of the turbulent velocity field. In the strict limit of applicability of Fick's law, the relationship between K and the pdf is used to investigate the influence of non-Gaussianity on dispersion in homogeneous turbulence. A bi-Gaussian pdf is used as a closure model that allows for separate studies of skewness and kurtosis variations. The choice of model parameters can have a significant influence on K, especially when the pdf is bimodal. Both arbitrariness of the closure and bimodality are then reduced using the maximum entropy criterion for the selection of the free parameter of the closure scheme, together with the assumption that the model is valid only for those values of the parameters for which a unimodal pdf is possible. The variations of K are found to be sensitive to both skewness and kurtosis showing a more complex behaviour than that found in literature. Kluwer Academic Publishers, 2000 Turbulent dispersion nationallicence Eddy diffusion coefficient nationallicence Probability density function nationallicence Maurizi A. ISAO-CNR, v. Gobetti 101, I-40129, Bologna, Italy aut Lorenzani S. ISAO-CNR, v. Gobetti 101, I-40129, Bologna, Italy aut Boundary-Layer Meteorology Kluwer Academic Publishers 95/3(2000-06-01), 427-436 0006-8314 95:3<427 2000 95 10546 https://doi.org/10.1023/A:1002613403385 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1023/A:1002613403385 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Maurizi A. ISAO-CNR, v. Gobetti 101, I-40129, Bologna, Italy aut NATIONALLICENCE 700 1- Lorenzani S. ISAO-CNR, v. Gobetti 101, I-40129, Bologna, Italy aut NATIONALLICENCE 773 0- Boundary-Layer Meteorology Kluwer Academic Publishers 95/3(2000-06-01), 427-436 0006-8314 95:3<427 2000 95 10546 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer