Computational Mathematics and Mathematical Physics

, Volume 48, Issue 10, pp 1784–1810

Third-order nonlinear dispersive equations: Shocks, rarefaction, and blowup waves

Article

DOI: 10.1134/S0965542508100060

Cite this article as:
Galaktionov, V.A. & Pohozaev, S.I. Comput. Math. and Math. Phys. (2008) 48: 1784. doi:10.1134/S0965542508100060

Abstract

Shock waves and blowup arising in third-order nonlinear dispersive equations are studied. The underlying model is the equation in
$$ u_t = (uu_x )_{xx} in\mathbb{R} \times \mathbb{R}_ + . $$
(0.1)
It is shown that two basic Riemann problems for Eq. (0.1) with the initial data
$$ S_ \mp (x) = \mp \operatorname{sgn} x $$
exhibit a shock wave (u(x, t) ≡ S(x)) and a smooth rarefaction wave (for S+), respectively. Various blowing-up and global similarity solutions to Eq. (0.1) are constructed that demonstrate the fine structure of shock and rarefaction waves. A technique based on eigenfunctions and the nonlinear capacity is developed to prove the blowup of solutions. The analysis of Eq. (0.1) resembles the entropy theory of scalar conservation laws of the form ut + uux = 0, which was developed by O.A. Oleinik and S.N. Kruzhkov (for equations in x ∊ ℝN) in the 1950s–1960s.

Keywords

general theory of partial differential equationsnonlinear dispersive equationsshock wavesrarefaction and blowup wavesRiemann’s problementropy theory of scalar conservation laws

Copyright information

© Pleiades Publishing, Ltd. 2008

Authors and Affiliations

  1. 1.Department of Mathematical SciencesUniversity of BathBathUK
  2. 2.Steklov Institute of MathematicsRussian Academy of SciencesMoscowRussia