Investigation of material wear formation on centrifugal fan impeller

Abstract: This paper reports the investigation of wear formation on centrifugal fan impeller which was exposed to bagasse ash particles in the sugar process plant and to simulate what took place as particles impact on the impeller surface. Computational Fluid Dynamics has been used as a tool to simulate impaction of flow around the impeller to determine the impingement angles and velocity particles. After performing simulation using SolidWorks, angle of impingement was found to be low at the impeller inlet and gradually increase angle toward 90°, in reference to the blade root. The lowest angle found after simulation was 23°. This angle correlate with the theory mentioned for ductile material, stating that ductile material is susceptible to wear formation when the impact angle is between 15° and 45° with a peak at 25°. Computational Fluid Dynamics using SolidWorks has been verified by using a third‐party company that worked on Creo 3.0 simulation. Research has revealed that material selection based on particles impingement angle, is key as when applied to centrifugal fans and related applications

COVID-19-related stigma within a rural South African community:A mixed methods analysis

BACKGROUND: Infectious disease-related stigma is a pervasive global issue that impedes disease control efforts by increasing reluctance to seek treatment or engagement in prevention behaviors for fear of ostracism. Despite this, there is limited research on COVID-19 stigma in Africa, specifically rural South Africa, which has faced infectious disease-related stigma throughout the HIV epidemic.METHODS: Population-based surveys were conducted among 1,662 adults living in the Agincourt Health and Socio-Demographic Surveillance System (AHDSS) area in Mpumalanga, South Africa, in August-October 2020 and August-October 2021. Surveys measured anticipated COVID-19-related stigma from low to high levels. Changes in stigma between surveys were compared using Wilcoxon ranked sign tests, and log-binomial models estimated the association between socio-demographic factors and anticipated stigma at both intervals. Qualitative interviews were conducted in 2022 among 31 adults who completed the original surveys, and the data were analyzed thematically to describe anticipated, perceived, and enacted stigma.RESULTS: Anticipated stigma significantly decreased from the first to the second survey (p-value:&lt;0.0001). Stigma was significantly higher among older age groups. In 2020, those less knowledgeable about COVID-19 were 2.24 times as likely to have higher levels of anticipated stigma compared to those who were more knowledgeable (RR:2.24, 95% CI: 1.90,2.64). Fear of being stigmatized influenced willingness to disclose infection. Participants perceived COVID-19 stigma as similar to HIV/AIDS stigma, but concern and fear reduced over time, with differences observed across generations and sexes. For some, fear of death and mistrust of others endorsed enacting stigma toward others.CONCLUSION: While COVID-19 stigma decreased over time in rural South Africa, different forms of stigma persisted and influenced participants' willingness to reveal their COVID-19 infection status. Given South Africa's history with infectious disease-related stigma hindering public health efforts, it is crucial that government bodies prioritize strategies to mitigate stigma in rural communities.</p

COVID-19 vaccine hesitancy in rural South Africa: Deepening understanding to increase uptake and access

Background: To date, COVID-19 vaccine coverage in the African region falls far too short of global goals. Increasing vaccination rates requires understanding barriers to vaccination so that effective interventions that sensitively and effectively address barriers to vaccination can be implemented. Methods: To assess COVID-19 vaccination levels and identify major barriers to vaccine uptake we conducted a population-based, cross-sectional survey among 1662 adults 18 and older from August 25 to October 29 2021 in the Agincourt Health and Socio-Demographic Surveillance System (AHDSS) area, Mpumalanga, South Africa. Results: Half of participants reported receiving a COVID-19 vaccine (50.4%) with 41.1% being fully vaccinated and 9.3% being partially vaccinated; 49.6% were unvaccinated. More women than men were vaccinated (55.5% vs 42.8%, P < 0.001), and older age groups were more likely to be vaccinated than younger age groups (P < 0.001). Among the unvaccinated, 69.0% planned to get vaccinated as soon as possible, while 14.7% reported definitely not wanting the vaccine. Major barriers to vaccination included lacking information on eligibility (12.3%) or where to get vaccinated (13.0%), concerns about side effects (12.5%), and inconvenient hours and locations for vaccination (11.0%). Confidence in the safety and efficacy of COVID-19 vaccines was higher among those vaccinated than unvaccinated (75.3% vs 51.2%, 75.8% vs 51.0%, both P < 0.001, respectively). Conclusions: Increasing vaccination in South Africa beyond current levels will require a concerted effort to address concerns around vaccine safety and increase confidence in vaccine efficacy. Clarifying eligibility and ensuring access to vaccines at times and places that are convenient to younger populations, men, and other vulnerable groups is necessary

The contribution of community gardens to food security in the Maphephetheni uplands

Although community gardens are widely promoted, very little empirical evidence exists of their contribution to food security. This study evaluated the contribution of community gardens to alleviating food insecurity for 53 community gardeners in Maphephetheni, KwaZulu-Natal, South Africa. Using the Household Food Insecurity Access Scale, it was found that 89% of these households were anxious about food supplies, consumed insufficient food and were severely food insecure. In addition, 72% consumed poor quality food. Community gardens were unable to solve the problem of food insecurity, but their contribution to consumption cannot be entirely ignored. Improved productivity and appropriate agricultural and nutritional advice are necessary. Land availability needs to be addressed through community and other redress systems to grant communities access to less marginal and more accessible productive land close to water. Programmes to support nonfarm income are needed and could provide incentives for increased production.http://www.tandfonline.com/loi/cdsa20hb2016Agricultural Economics, Extension and Rural Developmen