Global regularity and optimal decay estimates of large solutions to the compressible FENE system

TL;DR

This paper establishes global regularity and optimal decay rates for large solutions to the compressible FENE system, extending classical results and employing advanced mathematical techniques.

Contribution

It proves global regularity in $H^2$ for large data and derives optimal decay estimates without smallness assumptions, using Fourier splitting and Littlewood-Paley theory.

Findings

Global regularity in $H^2$ for large initial data.

Optimal decay rates in $H^1$ without smallness constraints.

Decay rate for highest derivatives using time frequency decomposition.

Abstract

In this paper, we are concerned with the compressible FENE dumbbell model. By virtue of the dissipative structure and the interpolation method, we firstly prove global regularity in $H^2$ framework for the compressible FENE system with some large data. Then, we obtain optimal decay estimates of large solutions in $H^1$ and remove the smallness assumption of low frequencies by virtue of the Fourier splitting method and the Littlewood-Paley decomposition theory. Furthermore, we establish optimal decay rate for the highest derivative of the solutions by a different method combining time frequency decomposition and the time weighted energy estimate. These obtained results generalize and cover the classical results of the incompressible FENE dumbbell model.