The Blow-Up Rate for a Semilinear Parabolic System

Blow-up estimates for a semilinear coupled parabolic system

This work deals with a semilinear parabolic systemwhich is coupled both in the equations and in the boundary conditions. The blow-up phenomena of its positive solutions are studied using the scaling method, the Green function and Schauder estimates. The upper and lower bounds of blow-up rates are then obtained. Moreover we show the influences of the reaction terms and the boundary absorption te...

The Blow–up Rate for a Semilinear Parabolic Equation with a Nonlinear Boundary Condition

In this paper we obtain the blow-up rate for positive solutions of ut = uxx−λu, in (0, 1)×(0, T ) with boundary conditions ux(1, t) = uq(1, t), ux(0, t) = 0. If p < 2q − 1 or p = 2q − 1, 0 < λ < q, we find that the behaviour of u is given by u(1, t) ∼ (T − t) − 1 2(q−1) and, if λ < 0 and p ≥ 2q − 1, the blow up rate is given by u(1, t) ∼ (T − t) − 1 p−1 . We also characterize the blow-up profil...

Blow-up at the Boundary for Degenerate Semilinear Parabolic Equations

This paper concerns a superlinear parabolic equation, degenerate in the time derivative. It is shown that the solution may blow up in finite time. Moreover it is proved that for a large class of initial data blow-up occurs at the boundary of the domain when the nonlinearity is no worse than quadratic. Various estimates are obtained which determine the asymptotic behaviour near the blow-up. The ...

Blow-up Estimates for Higher-order Semilinear Parabolic Equations

Interior Gradient Blow-up in a Semilinear Parabolic Equation

We present a one dimensional semilinear parabolic equation for which the spatial derivative of solutions becomes unbounded in finite time while the solutions themselves remain bounded. In our example the derivative blows up in the interior of the space interval rather than at the boundary, as in earlier examples. In the case of monotone solutions we show that gradient blow-up occurs at a single...