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To alleviate the shock boundary layer interaction adverse effects, various active or passive flow control strategies have been investigated in the literature. This research sheds light on the behavior of perforated plates as passive flow control techniques applied to NACA0012 airfoils in cascade configurations. Two identical perforated plates with shallow cavities underneath are accommodated on the upper and lower surfaces of each airfoil in the cascade arrangement. Six different cascade arrangements, including a baseline configuration with no control applied, are additively manufactured, with different perforated plate orifice sizes in the range of 0.5–1.2 mm. A high-speed wind tunnel with Schlieren optical diagnosis and wall static pressure taps is used to investigate the changes in the shock waves pattern triggered by the perforated plates. Steady 3D density-based numerical simulations in Ansys FLUENT are conducted for further analysis and validation. In the cascade configuration, the perforated plates alter the shock structure, and the strong normal shock wave is replaced by a weaker X-type shock structure. Eventually, a 1% penalty in overall total pressure loss is induced by the perforated plates because of the negative loss balance between the reduced shock losses and the enhanced viscous losses. Further studies on perforated plate geometrical features are needed to improve this outcome in a cascade arrangement. [ABSTRACT FROM AUTHOR]

Since its accession to the European Union, Romania has been working to strengthen its support for area-based approaches in local development, including the implementation of the LEADER approach. This has been made possible through increased financial support and the establishment of Local Action Groups (LAGs) throughout the country. The growing number of LAGs in Romania indicates an increasing recognition of the importance of bottomup approaches and local empowerment. LAGs serve as platforms for collaboration and coordination among various stakeholders, including local authorities, civil society organizations, and businesses. They enable communities to take ownership of their development processes and design strategies that are tailored to their specific contexts. This paper presents a comparative analysis of LEADER programme implementation in Romania in two programming periods (2007 - 2013 and 2014 - 2020), from the point of view of territorial distribution of funds, type of projects and beneficiaries, using choropleth maps with data at NUTS3 and LAU2 level. The results of the analysis show a modification of the behaviour of public and private beneficiaries, willing to involve their own funds in the realization of their projects, and the LAGs maturity in financing innovative projects and projects that develop existing businesses. The article proposes future research of LEADER impact at national and regional levels from the social return perspective. [ABSTRACT FROM AUTHOR]