Multidisciplinary Optimization Of In Flight Electro Thermal Ice Protection Systems

"The numerical multidisciplinary analysis and optimization of in-flight electro-thermal ice protection systems (IPS), in both anti-icing and de-icing modes, are presented by introducing general methodologies. The numerical simulation of the IPS is carried out by solving the conjugate heat transfer (CHT) problem between the fluid and solid domains. The sensitivity analysis of the energy requirements of anti-icing systems is performed with respect to different parameters, such as airspeed, angle of attack (AoA), ambient temperature, liquid water content and median volumetric diameter (MVD). For optimization, the goal is to reduce the power demand of the electro-thermal IPS, while ensuring a safe protection against icing. The design variables taken into account include power density, and the extent and activation time (in case of de-icing) of the electric heating blankets. Various constrained problem formulations for optimization in both the running-wet and evaporative regimes are presented. The formulations are carefully proposed from the physical and mathematical viewpoints; their performance is assessed by means of several numerical test cases to determine the most promising for each regime. The optimization is conducted using the mesh adaptive direct search (MADS) algorithm, which needs a large number of evaluations of the objective and constraint functions. This would be impractical as aero-icing flow simulations are computationally intensive and prohibitive, especially when coupled with conjugate heat transfer calculations, as for ice protection systems. Instead a surrogate-based optimization approach using reduced order modeling is proposed. In this approach, proper orthogonal decomposition (POD), in conjunction with Kriging, is used to replace the expensive CHT simulations. The results obtained show that the methodology is efficient and reliable in optimizing electro-thermal ice protection systems in particular, and thermal-based ones in general." --