Experimental investigation on the effect of the duct geometrical parameters on the performance of a ducted wind turbine

This paper reports an experimental investigation on the effect of the duct geometry on the aerodynamic performance of an aerofoil shaped ducted wind turbine (DWT). The tested two-dimensional model is composed of an aerofoil equipped with pressure taps and a uniform porous screen. The experimental setup is based on the assumption that the duct flow is axisymmetric and the rotor can be simulated as an actuator disc. Firstly, different tip clearances between the screen and the aerofoil are tested to point out the influence of this parameter on the DWT performance in terms of aerofoil pressure distribution, aerofoil lift and flow field features at the duct exit area. Then, the combined effect of tip clearance, of the angle of attack and of the screen position along the aerofoil chord is evaluated through a Design of Experiments (DoE) based approach. The analysis shows that, among the analysed range of design factor variation, increasing angle of attack and the tip clearance leads to a beneficial effect on the lift and back-pressure coefficients, while they show a poor dependence upon the screen axial position. Finally, the configuration characterized by the maximum value of all three main factors (15 degree of angle of attack, 5% of tip clearance and 30% backward to the nozzle plane), has the best values of lift coefficient and back-pressure coefficient.Wind Energ

Garnering an In-depth Understanding of Men Who Have Sex with Men in Chennai, India: A Qualitative Analysis of Sexual Minority Status and Psychological Distress

Men who have sex with men (MSM) in India are a hidden and largely understudied population, and havean HIV prevalence 17 times higher than that of the general Indian population. Experiences of social marginalization and negative psychosocial conditions occur concurrent to HIV risk among Indian MSM. To better understand the contextual variables driving HIV risk and inform intervention development, five focus groups (n = 46) and nine key informant interviews were conducted with 55 MSM in Chennai in 2010. NVivo software was used to code the transcripts, and data were analyzed using qualitative descriptive analysis methodology. Participants described sources of psychological distress and low self-worth related to gender non-conformity and sexual minority status. These included stigma from society, pressure to marry, lack of familial acceptance, childhood sexual abuse, and the imperative to keep sexual minority status a secret. Participants' personal evaluations revealed that self-acceptance may be an important resilience factor that can shield these psychosocial and HIV risk factors. In promoting health-seeking behavioral changes for Indian MSM at an individual level, our findings point to the potential strength of strategies that focus on self-acceptance of one's sexual minority identity to foster better psychosocial and overall health