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The purpose of this paper is to study turbulent flow separation at the airfoil trailing edge. This work aims to improve the knowledge of stall phenomenon by creating a QDNS database for the NACA412 airfoil.

Quasi-DNS simulations of the NACA 4412 airfoil in pre-stall conditions have been completed. The Reynolds number based on airfoil chord and freestream velocity is equal to 0.35 million, and the freestream Mach number to 0.117. Transition is triggered on both surfaces for avoiding the occurrence of laminar separation bubbles and to ensure turbulent mixing in the wake. Four incidences have been considered, 5, 8 10 and 11 degrees.

The results obtained show a reasonably good correlation of the present simulations with classical MSES airfoil simulations and with RANS computations, both in terms of pressure and skin-friction distribution, with an earlier and more extended flow separation in the QDNS. The database thus generated will be deeply analysed and enriched for larger incidences in the future.

No experimental or HPC numerical database at reasonable Reynolds number exists in the literature. The current work is the first step in that direction.

Drawing on the French case, this article examines the size and scope of poverty resulting from the coronavirus disease 2019 (COVID-19) pandemic, the diversity of poverty's manifestations and the role of public action (among other actors) in addressing the poverty. This reflection unfolds at the confluence between the international literature on the economic effects of COVID-19 around the world and the methodological and conceptual issues on poverty.

Following a research report to the French Government in 2021, a new academic collaboration is initiated to assess the conceptual issues underlying the report's nine quantitative, qualitative and participatory studies. A thematic analysis is used to elaborate on an original framework.

COVID-19 not only had detrimental economic effects on specific groups, such as precarious workers and students, but also serious effects on social isolation, mental health, access to welfare and public services. Together with assessing the consequences of the COVID-19 pandemic on poverty in France, this paper highlights the lack of recognition of community support in the face of hard times.

The COVID-19 outbreak has not only deteriorated socioeconomic situations in France, but has also unmasked structural, long-term components of poverty. The paper discusses three policy implications of these revelations, concerning (1) the monitoring of non-monetary dimensions of poverty, (2) the needs of various groups under a welfare state with a dual structure and (3) the role of communities in public policy schemes.