EXCELLERATP2 D2.11 Updated Report on the Alya Application Use Case

This document summarises the progress made in the 4th use case (UC-4) Fully integrated air-craft simulations with emissions models from the beginning of EXCELLERAT P2 and at the last section it focuses on the progress made since Month (M) 12. The first section introduces the use case, and the second details its objectives. The workflow is presented in the third section. The fourth section describes progress made during the first year, and section five presents the steps for the following period.In summary, the workflow development for UC-4 has progressed according to the schedule defined in deliverable D2.1. Work has been performed on the individual tasks planned for the project's first and second year. This use case focuses on generating a multiphysics platform that integrates advanced simulation techniques from Computational Fluid Dynamics (CFD) codes and massively parallel work-flows using leading-edge HPC architectures. Fully integrated simulations of the aircraft and propulsive system will be conducted with advanced High-Performance Computing (HPC) al-gorithms to obtain detailed predictions of aerodynamic parameters and emissions characteris-tics, including non-CO2 effects like nitrous oxide (NOx) or soot. To enable digital twins of fully integrated aircraft simulations, we plan to integrate coupled external aerodynamics with engine emissions simulations over scale resolving simulation meth-ods, including flow control devices and high-fidelity combustion simulations. In EXCELLERAT P1, Alya's standard low-order finite element version was used. For EXCEL-LERAT P2, we are working on a new high-order version. During the project's first year, we focused on validating the code for problems of increased complexity. Section four presents result for a Taylor Green vortex, channel flow, flow around a Windsor model car, and a simpli-fied aircraft. Progress had been slightly slower than expected due to a lack of computational resources originated by the delay in the installation of Marenostrum 5. The system is fully op-erational since March 2024. The project's second year was devoted to improving Wall Modelled Large Eddy Simulations (WMLES) of more complex geometries and coupling the flow simulations with a combustion model. For the second task, the Combustion group, led by Daniel Mira, opened a position and it has been filled since January 2025. The activity on this task is still going on.