Global stability of combination of viscous contact wave with rarefaction waves for the compressible fluid models of Korteweg type

TL;DR

This paper proves the large-time stability of a combined wave pattern in one-dimensional compressible Korteweg fluid models with variable viscosity, capillarity, and heat conduction, under certain smallness conditions.

Contribution

It establishes the asymptotic stability of viscous contact and rarefaction waves for complex fluid models with large initial data and variable coefficients, using refined energy estimates.

Findings

The combined wave pattern is asymptotically stable.

Uniform bounds on specific volume and temperature are derived.

Stability holds under smallness conditions on wave strength and heat conductivity.

Abstract

This paper is concerned with the large-time behavior of solutions to the Cauchy problem of the one-dimensional compressible fluid models of Korteweg type with density- and temperature-dependent viscosity, capillarity, and heat conductivity coefficients, which models the motions of compressible viscous fluids with internal capillarity. We show that the combination of the viscous contact wave with two rarefaction waves is asymptotically stable with a large initial perturbation if the strength of the composite wave and the heat conductivity coefficient satisfy some smallness conditions. The proof is based on some refined $L^2$-energy estimates to control the possible growth of the solutions caused by the highly nonlinearity of the system, the interactions of waves from different families and large data, and the key ingredient is to derive the uniform positive lower and upper bounds on the specific volume and the temperature.