Parabolic systems of forward-backward type exhibiting (p,q)-type growth

<p>This thesis is concerned with systems of nonlinear equations exhibiting both forwardbackward type behaviour, and non-standard growth conditions. A motivating problem in one spatial dimension with application to the Met Office is discussed before proceeding to consider higher dimensional...

Mô tả đầy đủ

Chi tiết về thư mục
Tác giả chính: Caddick, M
Tác giả khác: Süli, E
Định dạng: Luận văn
Được phát hành: 2018
Miêu tả
Tóm tắt:<p>This thesis is concerned with systems of nonlinear equations exhibiting both forwardbackward type behaviour, and non-standard growth conditions. A motivating problem in one spatial dimension with application to the Met Office is discussed before proceeding to consider higher dimensional problems.</p> <p>In the higher dimensional setting, in the absence of a monotonicity condition we work within the framework of Young measure solutions. We prove existence of large-data globalin- time Young measure solutions to initial-boundary-value problems for multidimensional nonlinear systems of forward-backward type of the form @<sub>t</sub>u − div(a(Du)) + Bu = F, where B ∈ R<sup>m×m</sup>, Bv·v ≤ 0 for all v ∈ R<sup>m</sup>, F is an m-component vector-function defined on a bounded open Lipschitz domain Ω ⊂ R<sup>n</sup>, and a is a locally Lipschitz mapping of the form a(A) = K(A)A, where K : R<sup>m×n</sup> → R. The long-time behaviour of these Young measure solutions is then studied, and under suitable assumptions on the source term we show convergence to Young measure solutions of the corresponding time-independent equations. We also discuss how the results proven can be adapted to cover mappings a which have different structure.</p> <p>We develop a numerical algorithm for the approximate solution of problems in this class, and we prove the convergence of the algorithm to a Young measure solution of the system under consideration.</p>