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The purpose of this paper is to describe experimental and numerical investigations focussed on the shock wave modification induced by a dc glow discharge. The model is a flat plate in a rarefied Mach 2 air flow, equipped with a plasma actuator composed of two electrodes. The natural flow without actuation exhibits a shock wave with a hyperbolic shape. When the discharge is on, the shock wave shape remains hyperbolic but the shock wave is pushed forward, leading to an increase in the shock wave angle. In order to discriminate thermal effects from purely plasma ones, the plasma actuator is then replaced by an heating element.

The experimental study is carried out with the super/hypersonic wind tunnel MARHy located at the ICARE Laboratory in Orléans. The experimental configuration with the heating element is simulated with a code using the 2D full compressible Navier-Stokes equations adapted for the rarefied conditions.

For heating element temperatures equal to the flat plate wall surface ones with the discharge on, experimental and numerical investigations showed that the shock wave angle was lower with the heating element, only 50 percent of the values got with the plasma actuator, meaning that purely plasma effects must also be considered to fully explain the flow modifications observed. The results obtained with the numerical simulations are then used to calculate the aerodynamic forces, i.e. the drag and the lift. These numerical results are then extrapolated to the plasma actuator case and it was found that the drag coefficient rises up to 13 percent when the plasma actuator is used, compared to only 5 percent with the heating element.

This paper matters in the topic of atmospheric entries where flow control, heat management and aerodynamic forces are of huge importance.

This study compares retirement in Chile and Uruguay, and focuses on current individuals legally entitled to retire, particularly women. The article analyses how labour market and family resources shape the access of women and men to social insurance by investigating the likelihood of retirement after reaching the legal age of retirement.

This study uses the Longitudinal Social Protection Survey (LSPS), a biannual or triennial longitudinal survey carried out in six Latin American countries. To study gender differences in the chance of being retired, the study conducts a series of logit regression models to model retirement as a function of labour market and life course conditions as well as providing descriptive and contextual information.

Main findings support labour market explanations of gender differences in retirement. Work experience, human capital and contribution densities largely explain the chances of retirement and economic autonomy among elderly women. Further analysis reveal that they are both less likely than men to retire but also to work in old age, limiting their economic autonomy.

Data for Uruguay are recent. To maximize comparison between countries, the paper selects the more recent waves with complete administrative information. As a result, the article uses cross-sectional data that might not capture the accumulation of family resources and could fail to provide a complete gendered life course explanation of current disadvantages faced by women.

The article uses novel data in order to place two Latin American countries within mainstream sociological theories of retirement, thus complementing literature that mainly focuses on European and North-American societies. The paper also documents gender gaps in retirement in two different Latin American societies, one with a traditionally generous public pension system (Uruguay) and one with a largely privately-run contributory system (Chile).