Speakers
Description
The French Space Operation Act (LOS) adopted in 2008 has established a national regime of authorization and supervision for space activities. CNES, the French Space Agency, is in charge of ensuring the right application of this Space Operation Act. In this context, to predict the debris survivability of a space vehicle and its associated fragments during their atmospheric re-entry, and assess the prospective risk on the ground, CNES develops its own spacecraft-oriented tool named PAMPERO. PAMPERO is a multidisciplinary tool that models the complete atmospheric reentry of a spacecraft including the fragmentation and ablation processes, along a six DOF trajectory.
Over the past 30 years, numerous methods and tools have been developed to simulate spacecraft breakup during atmospheric re-entry, predict the characteristics of the surviving fragments, and estimate the ground casualty risk. With the introduction of the Design for Demise concept, these tools are used for designing spacecraft that eventually break up and burn up during re-entry, thus usually reducing debris impact risk. To enhance both the accuracy and efficiency of predictions, researchers made continuous improvements in this field, especially in the last decade, but uncertainties and gaps in knowledge remain.
The PAMPERO Hifi (high-fidelity) code has been developed since 2019, with the aim of using high-fidelity codes to deal with the physics of atmospheric re-entry. Recent studies show that the parameters that have the most impact on the spacecraft's demise are the predictions of the heat load and the fragmentation process. It is therefore of prime importance to close the gaps that are existing in the spacecraft-oriented codes,
Especially :
Start discarding correlations based on Modified Newton laws, as the shock interaction and wake flows cannot be accounted for. New methodology has been developed based on CFD/DSMC computations and Machine Learning Techniques : For continuous regime : activity ongoing between 2019-2024; For rarefied regime activity ongoing between 2024 and 2026
Take into account the detailed geometry and the aerodynamics load at each time step to compute a mechanical analysis. Activity completed between 2019 – 2022
Take into account the in-depth Pyrolysis process and gas fluxes generation, Mass transfer fluxes, Advection fluxes,Char creation, char ablation process and associated fluxes with outgasing phenomena activity ongoing between 2021-2024
The aim of this presentation is to show the strategy implemented in PAMPERO Hifi in order to be able to estimate the aerothermodynamics load and the fragmentation/ablation process with precision, while keeping computation time to a minimum.
