This paper deals with a boundary-value problem in two-dimensional smoothly bounded
domains for the coupled Keller–Segel–Stokes system
Here, one of the novelties is that the chemotactic sensitivity
S is not a scalar function but rather attains values in
R2×2, and satisfies
|S(x,n,c)|≤CS(1+n)−伪 with some
CS>0 and
伪>0. We shall establish the existence of global bounded classical solutions for arbitrarily large initial data. In contrast to the corresponding case of scalar-valued sensitivities, this system does not possess any gradient-like structure due to the appearance of such matrix-valued
S. To overcome this difficulty, we will derive a series of
a priori estimates involving a new interpolation inequality.
To the best of our knowledge, this is the first result on global existence and boundedness in a Keller–Segel–Stokes system with tensor-valued sensitivity, in which production of the chemical signal is involved.