Numerical analysis of the integration of wind turbines into the design of the built environment

The effect of wind distribution on the architectural domain of the Bahrain Trade Centre was numerically analysed using Computational Fluid Dynamics (CFD). Using the numerical data, the power generation potential of the building integrated wind turbines was determined in response to the prevailing wind direction. Simulating a reference wind speed of 6 m/s, the findings from the study quantified an estimate power generation of 6.4 kW indicating a capacity factor of 2.9% for the computational model. At the windward side of the building, it was observed that the layers of turbulence intensified in inverse proportion to the height of the building with an average value of 0.45 J/kg. The air velocity was found to gradually increase in direct proportion to the elevation with the turbine located at higher altitude receiving maximum exposure to incoming wind. This study highlighted the potential of using advanced computational fluid dynamics in order to factor wind into the design of any architectural environment

Design and Aerodynamic Investigation of Dynamic Architecture

The effect of the spacing between adjacent building floors on the wind distribution and turbulence intensity was analysed using computational fluid dynamics in this study. Five computational models were created with floor spacing ranging from 0.8 m (benchmark) to 1.6 m. The three-dimensional Reynolds-Averaged Navier–Stokes equations along with the momentum and continuity equations were solved using the FLUENT code for obtaining the velocity and pressure field. Simulating a reference wind speed of 5.5 m/s, the findings from the study quantified that at a floor spacing of 1.6 m, the overall wind speed augmentation was 39 % which was much higher than the benchmark model (floor spacing = 0.8 m) indicating an amplification in wind speed of approximately 27 %. In addition, the results indicated a gradual reduction in turbulence kinetic energy by up to 53 % when the floor spacing was increased from 0.8 to 1.6 m. Although the concept was to integrate wind turbines into the building fabric, this study is limited to the assessment of the airflow inside the spaces of building floors which can be potentially harnessed by a vertical axis wind turbine. The findings of this work have indicated that there is a potential for integration which will lead on to future research in this area

The Ionizing Radiation-Induced Bystander Effect: Evidence, Mechanism, and Significance

It has long been considered that the important biological effects of ionizing radiation are a direct consequence of unrepaired or misrepaired DNA damage occurring in the irradiated cells. It was presumed that no effect would occur in cells in the population that receive no direct radiation exposure. However, in vitro evidence generated over the past two decades has indicated that non-targeted cells in irradiated cell cultures also experience significant biochemical and phenotypic changes that are often similar to those observed in the targeted cells. Further, nontargeted tissues in partial body-irradiated rodents also experienced stressful effects, including oxidative and oncogenic effects. This phenomenon, termed the “bystander response,” has been postulated to impact both the estimation of health risks of exposure to low doses/low fluences of ionizing radiation and the induction of second primary cancers following radiotherapy. Several mechanisms involving secreted soluble factors, oxidative metabolism, gap-junction intercellular communication, and DNA repair, have been proposed to regulate radiation-induced bystander effects. The latter mechanisms are major mediators of the system responses to ionizing radiation exposure, and our knowledge of the biochemical and molecular events involved in these processes is reviewed in this chapter

COVID-19-related absence among surgeons: development of an international surgical workforce prediction model

Background: During the initial COVID-19 outbreak up to 28.4 million elective operations were cancelled worldwide, in part owing to concerns that it would be unsustainable to maintain elective surgery capacity because of COVID-19-related surgeon absence. Although many hospitals are now recovering, surgical teams need strategies to prepare for future outbreaks. This study aimed to develop a framework to predict elective surgery capacity during future COVID-19 outbreaks. Methods: An international cross-sectional study determined real-world COVID-19-related absence rates among surgeons. COVID-19-related absences included sickness, self-isolation, shielding, and caring for family. To estimate elective surgical capacity during future outbreaks, an expert elicitation study was undertaken with senior surgeons to determine the minimum surgical staff required to provide surgical services while maintaining a range of elective surgery volumes (0, 25, 50 or 75 per cent). Results Based on data from 364 hospitals across 65 countries, the COVID-19-related absence rate during the initial 6 weeks of the outbreak ranged from 20.5 to 24.7 per cent (mean average fortnightly). In weeks 7–12, this decreased to 9.2–13.8 per cent. At all times during the COVID-19 outbreak there was predicted to be sufficient surgical staff available to maintain at least 75 per cent of regular elective surgical volume. Overall, there was predicted capacity for surgeon redeployment to support the wider hospital response to COVID-19. Conclusion: This framework will inform elective surgical service planning during future COVID-19 outbreaks. In most settings, surgeon absence is unlikely to be the factor limiting elective surgery capacity

Does corporate reputation matter? Role of social media in consumer intention to purchase innovative food product

The exponential growth of the corporate reputation in food industry has resulted in innovations in every link of its supply chain. There have been studies that have characterized innovation in various industries from the perspective of technology, but far fewer in the area of corporate reputation, consumer perception, and intention towards innovations in food products. This research analyses the innovations in the food industry from the perspective of the consumer and provides a conceptual framework of food innovation stages. The study also investigates the relationship between corporate reputation and intention towards food innovation along with the other components of TPB model with an extension of social media engagement. The results from India and US samples confirm that social media engagement have a significant role to play in creating intention to purchase innovative food products. The study compares the US and Indian samples and identifies differences in subjective norms and perceived behavioural control

The influence of structural morphology on the efficiency of building integrated wind turbines (BIWT)

A numerical investigation was carried out to determine the impact of structural morphology on the power generation capacity of building-integrated wind turbines. The performance of the turbines was analysed using the specifications of the Bahrain Trade Centre which was taken as the benchmark model, the results of which were compared against triangular, square and circular cross-sections of the same building. The three-dimensional Reynolds-Averaged Navier-Stokes (RANS) equations along with the momentum and continuity equations were solved for obtaining the velocity and pressure field. Simulating a reference wind speed of 6 m/s, the findings from the study quantified an estimate power generation of 6.4 kW indicating a capacity factor of 2.9 % for the benchmark model. The square and circular configurations however determined greater capacity factors of 12.2 % and 19.9 %, recording an estimated power production capability of 26.9 kW and 35.1 kW and confirming the largest extraction of the incoming wind stream. The optimum cross-sectional configuration for installing wind turbines in high-rise buildings was the circular orientation as the average wind speed at the wind turbines was accelerated by 0.3 m/s resulting in an overall augmentation of 5 %. The results from this study therefore highlighted that circular building morphology is the most viable building orientation, particularly suited to regions with a dominant prevailing wind direction. - See more at: http://aimspress.com/aimse/ch/reader/view_abstract.aspx?file_no=20140302&flag=1#sthash.X2u7QIPC.dpu

Flame propagation and burning characteristics of pulverized biomass for sustainable biofuel

One of the critical energy challenges, which our planet is confronting today, is how to curtail the reliance on fossil fuels for a sustainable environment. Biomass is a promising source of renewable energy for sustainable power generation compared to the conventional coal. However, they are hard to mill to finer size due to their fibrous nature. In this study, the size dependency on the flame propagation and burning characteristics of pulverized biomass is examined compared to coals. Modified Hartmann and 1-m3 explosion vessels were used to perform flame speed and explosion tests. Fine-sized particles propagated the flame with a flame velocity of 2.5 m/s for non-spherical-shaped particles compared to round-shaped lycopodium and corn flour. For coarse size particles, the flame speeds were measured to be around 1 m/s. The minimum explosion concentration was measured to be 0.2–0.4 equivalence ratio for a size range of 40–200 μm and higher for larger particle sizes. Reactivity data showed functional correlations for selected biomass and coal samples. SEM images of post-explosion residues showed incomplete combustion of bigger particles and formation of the cenosphere because of siliceous contents. The study findings concluded that the fine-sized particles of biomass had higher fire/explosion risk due to greater burning characteristics and it could only be replaced with conventional coal after assessing their combustion data by reliable methods

Flame propagation and burning characteristics of pulverized biomass for sustainable biofuel

One of the critical energy challenges, which our planet is confronting today, is how to curtail the reliance on fossil fuels for a sustainable environment. Biomass is a promising source of renewable energy for sustainable power generation compared to the conventional coal. However, they are hard to mill to finer size due to their fibrous nature. In this study, the size dependency on the flame propagation and burning characteristics of pulverized biomass is examined compared to coals. Modified Hartmann and 1-m3 explosion vessels were used to perform flame speed and explosion tests. Fine-sized particles propagated the flame with a flame velocity of 2.5 m/s for non-spherical-shaped particles compared to round-shaped lycopodium and corn flour. For coarse size particles, the flame speeds were measured to be around 1 m/s. The minimum explosion concentration was measured to be 0.2–0.4 equivalence ratio for a size range of 40–200 μm and higher for larger particle sizes. Reactivity data showed functional correlations for selected biomass and coal samples. SEM images of post-explosion residues showed incomplete combustion of bigger particles and formation of the cenosphere because of siliceous contents. The study findings concluded that the fine-sized particles of biomass had higher fire/explosion risk due to greater burning characteristics and it could only be replaced with conventional coal after assessing their combustion data by reliable methods