The objective of the proposal is to advance fundamental science in reactive porous material modeling to foster innovation on the second pillar of the work program "Leadership in Enabling and Industrial Technologies". Starting from the most advanced development done at NASA in the last decade, state-of-the-art reactive porous material models will be improved further with the contribution of expert theoreticians and implemented in a simulation tool released open source. The fundamental developments will be validated and applied to design optimization and process innovation for two industrial applications. The first one is the design of efficient and optimized thermal protection systems for space exploration vehicles (subprogram "space").The second one targets bio-hydrocarbon and bio-carbon production from lignocellulosic biomass. The biomass pyrolysis process will be studied from the wood-cell scale to the process level. The goal is to develop advanced predictive engineering tools to enable process optimization and guide innovation in progress. This second effort will eventually benefit to two "Societal Challenges" of the work program: "Energy" and "Climate action, environment, resource efficiency, and raw materials".

The main objective of the ASSALA project is to develop a methodology to predict defect generation likelihood induced by the interaction of robot inaccuracies and thermal effects during the Laser Wire Deposition (LWD) process of Titanium integrating deterministic and advanced statistical models applied on the manufacturing of new generation aero engine structures. The novel activities to carry out during the project will be based on: - The development of a tool focused on the automatic path generation applied on to robotic LWD based on 5 degree of freedom deposition. - A dynamic robot model to compensate and estimate through Monte Carlo simulation the temporal positioning accuracy. - A fast and precise computation algorithm that will allow to solve the time consuming dynamic thermo-mechanical phenomena of the solidification process based on Finite Element Modelling through model order reduction strategies. - Implementation of process monitoring (thermal and visible) and control tools (CAM correction) for the implementation of adaptive control strategies which will correct the component distortion. - Integration of the developed algorithms in a methodology to predict the failure probability based on Monte Carlo statistical tools. - Testing and validation of the developed simulation tools and implemented adaptive control strategies. ASSALA aims at contributing to achieve more efficient and robust LWD processes provided that the end effector-to-component relative distance plays a major role in the stability of the process and in the generation of defects such as cracks or flaws that can induce the rejection of the deposits due to the critical structural nature of the aero engine components.

This project will combine wind tunnel experiments with numerical simulations and a sensitivity analysis to improve the control authority of pulsed jet actuators (PJAs) to separated turbulent flows over a 2.5D airfoil equipped with a flap. The target of this approach is to determine the minimum net-mass-flux required by pulsed jet actuators to compensate for the momentum deficit in the boundary layer. Controlling separation contributes to a decrease in the energy demand, leading to a decrease in CO2 emissions. It also improves the maneuvering capability, safety, and durability of the aircraft by reattaching the boundary layer and suppressing instabilities. The present work considers the sensitivity analysis, using a hierarchy of numerical models, using Reynolds-averaged Navier-Stokes simulations and large eddy simulations for both the flow inner and outer flow. These simulations will be calibrated using wind tunnel experiments by means of a data-assimilation method. The sensitivity analysis will then allow for determining the optimal parameters of the pulsed jet actuators such as operating frequency, output velocity together with their geometry including the actuators’ outflow aspect ratio, chordwise position and inter-actuator distance in the spanwise direction. The selected technology of PJAs will be an improved design of energy efficient fluidic oscillators capable of reaching high outflow velocities with operating frequencies ranging in the natural unstable frequencies of the outer flow. Novel manufacturing techniques such as xurography will also be tested to improve the cost and fabrication time of the PJAs, as well as their integration on the wing. Furthermore, the project will investigate the manufacturing and flow-control capabilities of dual-frequency fluidic oscillators, which may allow for further decreasing the net-mass-flux of the actuators by triggering instabilities with greater potential in altering boundary-layer separation.