Parameter identification in a semilinear hyperbolic system
- Egger, Herbert
- Kugler, Thomas
- Strogies, Nikolai
2010 Mathematics Subject Classification
- 35R30 49J20 49N45 65J22 74J25
- Parameter identification, semilinear wave equation, nonlinear inverse problem, Tikhonov regularization, approximate source condition, conditional stability
We consider the identification of a nonlinear friction law in a one-dimensional damped wave equation from additional boundary measurements. Well-posedness of the governing semilinear hyperbolic system is established via semigroup theory and contraction arguments. We then investigate the inverse problem of recovering the unknown nonlinear damping law from additional boundary measurements of the pressure drop along the pipe. This coefficient inverse problem is shown to be ill-posed and a variational regularization method is considered for its stable solution. We prove existence of minimizers for the Tikhonov functional and discuss the convergence of the regularized solutions under an approximate source condition. The meaning of this condition and some arguments for its validity are discussed in detail and numerical results are presented for illustration of the theoretical findings.
- Inverse Problems, 33 (2017), pp. 055022/1--055022/25, DOI 10.1088/1361-6420/aa648c .