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A topological derivative-based method for the reconstruction of multiple pollution sources

The topological derivative method is used to solve a pollution sources reconstruction problem governed by a steady-state convection-diffusion equation. The inverse problem consists in the reconstruction of a set of pollution sources in a fluid medium by measuring the concentration of the pollutants within some subregion of the reference domain. We rewrite the inverse problem as a topology optimization problem which allows us to solve it by using the concept of topological derivatives. The resulting algorithm is able to reconstruct the pollution sources in one step and is independent of any initial guess. A numerical example is presented to show the effectiveness of our reconstruction method.