
The flow of a thin film down an inclined plane is a canonical setup in fluid mechanics and associated technologies, with applications such as coating, where the liquid-gas interface should ideally be flat, and heat or mass transfer, where an increase of interfacial area is desirable. In each of these applications, we would like to robustly and efficiently manipulate the flow in order to drive the dynamics to a desired interfacial shape. In this talk, I will describe a control methodology based on same fluid blowing and suction through the wall. The controls will be developed using simplified models for a falling liquid film based on reduced-order modelling and asymptotic analysis. The goal is to develop control strategies at more cost-effective levels of the hierarchy and investigate their ability to translate across the hierarchy into real-life situations by using direct numerical simulations of the Navier-Stokes equations, which in this context act as an in silico experimental framework. I will discuss distributed controls as well as (more realistic) point-actuated controls, their robustness to parameter uncertainties and validity across the hierarchy of models. If there is time, I will also discuss recent work using optimal control of similar problems.