Boundedness and stabilization in a two-species chemotaxis-competition system of parabolic-parabolic-elliptic type

Masaaki Mizukami

Published 2017-03-24Version 1

This paper deals with the two-species chemotaxis-competition system $u_t = d_1 \Delta u - \chi_1 \nabla \cdot (u \nabla w) + \mu_1 u(1 - u - a_1 v)$, $v_t = d_2 \Delta v - \chi_2 \nabla \cdot (v \nabla w) + \mu_2 v(1 - a_2 u - v)$, $0 = d_3 \Delta w + \alpha u + \beta v - \gamma w$, where $\Omega$ is a bounded domain in $\mathbb{R}^n$ with smooth boundary, $n\ge 2$; $\chi_i$ and $\mu_i$ are constants satisfying some conditions. The above system was studied in the cases that $a_1,a_2\in (0,1)$ and $a_1>1>a_2$, and it was proved that global existence and asymptotic stability hold when $\frac{\chi_i}{\mu_i}$ are small. However, the conditions in the above two cases strongly depend on $a_1,a_2$, and have not been obtained in the case that $a_1,a_2\ge 1$. Moreover, convergence rates in the cases that $a_1,a_2\in (0,1)$ and $a_1 > 1 > a_2$ have not been studied. The purpose of this work is to construct conditions which derive global existence of classical bounded solutions for all $a_1,a_2>0$ which covers the case that $a_1,a_2 \ge 1$, and lead to convergence rates for solutions of the above system in the cases that $a_1,a_2\in (0,1)$ and $a_1\ge 1 >a_2$.