Asymptotic L1-decay of solutions of the porous medium equation to self-similarity

We consider the flow of gas in an N -dimensional porous medium with initial density v0 (x) ≥ 0. The density v(x, t) then satisfies the nonlinear degenerate parabolic equation vt = ∆v m where m > 1 is a physical constant. Assuming that (1 + $2 )v0 (x) dx < ∞, we prove that v(x, t) behaves asympto...

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Detalles Bibliográficos
Autores: Carrillo de la Plata, José Antonio, Toscani., G.
Tipo de recurso: artículo
Fecha de publicación:2000
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:115374
Acceso en línea:https://ddd.uab.cat/record/115374
https://dx.doi.org/urn:doi:10.1512/iumj.2000.49.1756
Access Level:acceso abierto
Descripción
Sumario:We consider the flow of gas in an N -dimensional porous medium with initial density v0 (x) ≥ 0. The density v(x, t) then satisfies the nonlinear degenerate parabolic equation vt = ∆v m where m > 1 is a physical constant. Assuming that (1 + $2 )v0 (x) dx < ∞, we prove that v(x, t) behaves asymptotically, as t → ∞, like the Barenblatt-Pattle solution V ( $, t). We prove that the L1 -distance decays at a rate t 1/((N+2)m−N) . Moreover, if N = 1, we obtain an explicit time decay for the L∞ distance at a suboptimal rate. The method we use is based on recent results we obtained for the Fokker-Planck equation [2], [3].