Special Session 8: Recent Progress on Mathematical Analysis of PDEs Arising in Fluid Dynamics

The Cauchy problem for an inviscid Oldroyd-B model in three dimensions: global well posedness and optimal decay rates
Sili Liu
Changsha University of Science and Technology
Peoples Rep of China
Co-Author(s):    Wenjun Wang; Huanyao Wen.
Abstract:
In this talk I will introduce our recent work on the Cauchy problem for an inviscid compressible Oldroyd-B model in three dimensions. The global well posedness of strong solutions and the associated time-decay estimates in Sobolev spaces are established near an equilibrium state. The vanishing of viscosity is the main challenge compared with [Wang-Wen, Sci.China Math., 2021] where the viscosity coefficients are included and the decay rates for the highest-order derivatives of the solutions seem not optimal. One of the main objectives of this paper is to develop some new dissipative estimates such that the smallness of the initial data and decay rates are independent of the viscosity. Moreover, we prove that the decay rates for the highest-order derivatives of the solutions are optimal, which is of independent interest. Our proof relies on Fourier theory and delicate energy method. This talk is based on joint works with Prof. Wenjun Wang and Prof. Huanyao Wen.