Eulerian Mapping Closure Approach for Probability Density Function of Concentration in Shear Flows
نویسندگان
چکیده
The Eulerian mapping closure approach is developed for uncertainty propagation in computational uid mechanics. The approach is used to study the Probability Density Function (PDF) for the concentration of species advected by a random shear ow. An analytical argument shows that uctuation of the concentration eld at one point in space is non-Gaussian and exhibits stretched exponential form. An Eulerian mapping approach provides an appropriate approximation to both convection and di usion terms and leads to a closed mapping equation. The results obtained describe the evolution of the initial Gaussian eld, which is in agreement with direct numerical simulations.
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