Optimal control problem associated with three-dimensional critical convective Brinkman-Forchheimer equations
Kush Kinra, Fernanda Cipriano
TL;DR
This work establishes a rigorous velocity-tracking optimal control framework for the $3$D critical convective Brinkman–Forchheimer equations on a bounded domain, with the control entering as a distributed force. The authors address the key difficulty of 3D regularity by deriving intermediate optimality conditions via a difference-quotient approach and regularizing an intermediate adjoint system, then passing to the limit. They prove the existence of an optimal state–control pair and derive the first-order necessary optimality conditions through a backward adjoint equation and a variational inequality that characterizes optimal forces. The results extend known 2D torus analyses to 3D bounded domains, providing a robust mathematical basis for velocity-tracking control in porous-media flows with potential industrial applications.
Abstract
In this article, we are concerned about the velocity tracking optimal control problem for 3D critical convective Brinkman-Forchheimer equations defined on a simply connected bounded domain $\mathbb{D}\subset\mathbb{R}^3$ with $\mathrm{C}^2$-boundary $\partial\mathbb{D}$. The control is introduced through an external force. The objective is to optimally minimize a velocity tracking cost functional, for which the velocity vector field is oriented towards a target velocity. Most importantly, we are concerned about the first-order necessary optimality conditions for above-mentioned optimal control problem which is the main challenging task of this article. To overcome the difficulties related to the differentiability of the control-to-state mapping, consequence of the lack of regularity of the state variable on bounded domains, we first establish some intermediate optimality conditions and then pass to the limit.
