Global weak solutions of a Hamiltonian regularised Burgers equation
Résumé
Inspired by a recent nondispersive conservative regularisation of the shallow water
equations, a similar regularisation is proposed and studied here for the inviscid Burgers equation.
The regularised equation is parametrised by a positive number $\ell$, the inviscid Burgers equation
corresponding to $\ell=0$ and the Hunter--Saxton equation being formally obtained letting $\ell\to
\infty$. The breakdown of local smooth solutions is demonstrated. The existence of two types of global
weak solutions, conserving or dissipating an $H^1$ energy, is also studied. The built
dissipative solution satisfies (uniformly with respect to $\ell$) an Oleinik inequality, as
do entropy solutions of the inviscid Burgers equation.
The limit (up to a subsequence) of the dissipative solution when $\ell\to 0$ (respectively
$\ell \to \infty$) satisfies the Burgers (resp. Hunter--Saxton) equation forced by an unknown remaining
term. At least before the appearance of singularities, the limit satisfies the Burgers (resp.
Hunter--Saxton) equation.
Origine | Fichiers produits par l'(les) auteur(s) |
---|
Loading...