An automatic methodology for estimating eddy diffusivities from experimental data

A technique for estimating eddy diffusivities in a turbulent atmospheric la yer is presented; the scheme adopted is based on an inverse-problem methodo logy. The inverse problem is formulated as a nonlinear constrained optimiza tion problem, where the objective function is defined through the square di fferences between experimental and model data. The direct mathematical mode l is given by the advection-diffusion equation, which is solved by second-o rder finite-difference method. In the presence of noise it is necessary to use some regularization term; the Tikhonov function and an entropic regular ization of zeroth, first and second orders are used in this paper. In addit ion, two inversion strategies are used: alternate and simultaneous eddy dif fusivities estimation. Numerical experiments show a good performance of the proposed methodology.