Existence results for a Cauchy-Dirichlet parabolic problem with a repulsive gradient term

Fuente: arXiv
Saved in:
Bibliographic Details
Main Author: Magliocca, Martina
Format: Preprint
Published: 2017
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866912198270386176
author Magliocca, Martina
author_facet Magliocca, Martina
contents We study the existence of solutions of a nonlinear parabolic problem of Cauchy-Dirichlet type having a lower order term which depends on the gradient. The model we have in mind is the following: \[ \begin{cases}\begin{split} & u_t-\text{div}(A(t,x)\nabla u|\nabla u|^{p-2})=γ|\nabla u|^q+f(t,x) &\qquad\text{in } Q_T,\\ & u=0 &\qquad\text{on }(0,T)\times \partial Ω,\\ & u(0,x)=u_0(x) &\qquad\text{in } Ω, \end{split}\end{cases} \] where $Q_T=(0,T)\times Ω$, $Ω$ is a bounded domain of $\mathrm{R}^N$, $N\ge 2$, $1<p<N$, the matrix $A(t,x)$ is coercive and with measurable bounded coefficients, the r.h.s. growth rate satisfies the superlinearity condition \[ \max\left\{\frac{p}{2},\frac{p(N+1)-N}{N+2}\right\}<q<p \] and the initial datum $u_0$ is an unbounded function belonging to a suitable Lebesgue space $L^σ(Ω)$. We point out that, once we have fixed $q$, there exists a link between this growth rate and exponent $σ=σ(q,N,p)$ which allows one to have (or not) an existence result. Moreover, the value of $q$ deeply influences the notion of solution we can ask for. The sublinear growth case with \[ 0<q\le\frac{p}{2} \] is dealt at the end of the paper for what concerns small value of $p$, namely $1<p<2$.
format Preprint
id arxiv_https___arxiv_org_abs_1703_00834
institution arXiv
publishDate 2017
record_format arxiv
spellingShingle Existence results for a Cauchy-Dirichlet parabolic problem with a repulsive gradient term
Magliocca, Martina
Analysis of PDEs
We study the existence of solutions of a nonlinear parabolic problem of Cauchy-Dirichlet type having a lower order term which depends on the gradient. The model we have in mind is the following: \[ \begin{cases}\begin{split} & u_t-\text{div}(A(t,x)\nabla u|\nabla u|^{p-2})=γ|\nabla u|^q+f(t,x) &\qquad\text{in } Q_T,\\ & u=0 &\qquad\text{on }(0,T)\times \partial Ω,\\ & u(0,x)=u_0(x) &\qquad\text{in } Ω, \end{split}\end{cases} \] where $Q_T=(0,T)\times Ω$, $Ω$ is a bounded domain of $\mathrm{R}^N$, $N\ge 2$, $1<p<N$, the matrix $A(t,x)$ is coercive and with measurable bounded coefficients, the r.h.s. growth rate satisfies the superlinearity condition \[ \max\left\{\frac{p}{2},\frac{p(N+1)-N}{N+2}\right\}<q<p \] and the initial datum $u_0$ is an unbounded function belonging to a suitable Lebesgue space $L^σ(Ω)$. We point out that, once we have fixed $q$, there exists a link between this growth rate and exponent $σ=σ(q,N,p)$ which allows one to have (or not) an existence result. Moreover, the value of $q$ deeply influences the notion of solution we can ask for. The sublinear growth case with \[ 0<q\le\frac{p}{2} \] is dealt at the end of the paper for what concerns small value of $p$, namely $1<p<2$.
title Existence results for a Cauchy-Dirichlet parabolic problem with a repulsive gradient term
topic Analysis of PDEs
url https://arxiv.org/abs/1703.00834