An inverse problem for a quasilinear convection--diffusion equation

Abstract

We study the inverse problem of recovering a semilinear diffusion term $a(t,\lambda )$ as well as a quasilinear convection term $\mathcal{B}(t,x,\lambda ,\xi )$ in a nonlinear parabolic equation $$\partial_tu-\textrm{div}(a(t,u) \nabla u)+\mathcal B(t,x,u,\nabla u)\cdot\nabla u=0, \quad \mbox{in}\ (0,T)\timesΩ,$$ given the knowledge of the flux of the moving quantity associated with different sources applied at the boundary of the domain. This inverse problem that is modeled by the solution dependent parameters $a$ and $\mathcal{B}$ has many physical applications related to various classes of cooperative interactions or complex mixing in diffusion processes. Our main result states that, under suitable assumptions, it is possible to fully recover the nonlinear diffusion term $a$ as well as the nonlinear convection term $\mathcal{B}$. The recovery of the diffusion term is based on the idea of solutions to the linearized equation with singularities near the boundary $\partial \Omega$. Our proof of the recovery of the convection term is based on the idea of higher order linearization to reduce the inverse problem to a density property for certain anisotropic products of solutions to the linearized equation. We show this density property by constructing sufficiently smooth geometric optic solutions concentrating on rays in $\Omega$.

References in corpus (4)

• Reconstruction for the coefficients of a quasilinear elliptic partial differential equation
• On the simultaneous recovery of the conductivity and the nonlinear reaction term in a parabolic equation
• Partial data inverse problems for quasilinear conductivity equations
• Recovery of nonlinear terms for reaction diffusion equations from boundary measurements

Cited by in corpus (3)

• An inverse boundary value problem for isotropic nonautonomous heat flows
• An inverse problem for semilinear equations involving the fractional Laplacian
• Rigidity of inverse problems for nonlinear elliptic equations on manifolds