Study of the Various Charactertics of a Helical Vertical Axis Wind Turbine Compared to a Straight Bladed Darrieus Design

As the wind energy market continues to expand, the need for a more diverse range of wind turbine technologies becomes increasingly apparent. Horizontal axis wind turbines (HAWT) have become the standard design for wind turbines over the past few decades and have been the go-to design used in wind farms both on land and off-shore. However, in residential and urban environments other types of turbine designs can help expand the reach of wind energy. Specifically, vertical axis wind turbines (VAWT) have shown potential for new applications of wind turbines in areas that are less suitable for typical HAWTs. The most common VAWT design is the Darrieus turbine, which use a series of straight, vertically oriented blades that rotate around an axis that is perpendicular to the incoming wind. However, this design has shown several disadvantages such as being unable to self-start and creating large amounts of noise. This project seeks to improve these characteristics by adding a helical twist to the blades of a Darrieus wind turbine and evaluating its benefits. With the addition of a helical twist, the gap between each blade begin to decrease as there is now a more fluid transition from one blade to the next as it rotates through the incoming wind. In VAWTs the blades chop through the incoming wind and in front of the center axis, which creates turbulence and causes a fluctuation in the torque produced by the center shaft. Adding a helical twist diminishes this “chopping” motion by allowing for a portion of the blades to nearly always be in front of the center axis. In order to evaluate the benefits of a helical VAWT, this thesis used a series of live wind tunnel tests and computational fluid dynamic simulations to measure the power output, torque fluctuation, and wake region turbulence of this type of turbine. It compared a helical VAWT with a straight bladed VAWT of the same dimensions. In addition, simulations were used to examine the turbulence in the wake region of the turbines as well as the torque fluctuation produced in the center shaft. The results showed the helical design was found to have an improvement in the power output compared to the straight bladed design and showed improved self-starting capabilities. From the CFD analysis, the helical design did not have any significant improvement in velocity recovery or in the torque fluctuation, and the helical design did only show a slight improvement in the wake region turbulence, which can translate into some noise reduction. The results of this research demonstrate how adding a helical angle to a Darrieus VAWT design improves multiple characteristics compared to its straight bladed counterpart

Study of the Various Charactertics of a Helical Vertical Axis Wind Turbine Compared to a Straight Bladed Darrieus Design

As the wind energy market continues to expand, the need for a more diverse range of wind turbine technologies becomes increasingly apparent. Horizontal axis wind turbines (HAWT) have become the standard design for wind turbines over the past few decades and have been the go-to design used in wind farms both on land and off-shore. However, in residential and urban environments other types of turbine designs can help expand the reach of wind energy. Specifically, vertical axis wind turbines (VAWT) have shown potential for new applications of wind turbines in areas that are less suitable for typical HAWTs. The most common VAWT design is the Darrieus turbine, which use a series of straight, vertically oriented blades that rotate around an axis that is perpendicular to the incoming wind. However, this design has shown several disadvantages such as being unable to self-start and creating large amounts of noise. This project seeks to improve these characteristics by adding a helical twist to the blades of a Darrieus wind turbine and evaluating its benefits. With the addition of a helical twist, the gap between each blade begin to decrease as there is now a more fluid transition from one blade to the next as it rotates through the incoming wind. In VAWTs the blades chop through the incoming wind and in front of the center axis, which creates turbulence and causes a fluctuation in the torque produced by the center shaft. Adding a helical twist diminishes this “chopping” motion by allowing for a portion of the blades to nearly always be in front of the center axis. In order to evaluate the benefits of a helical VAWT, this thesis used a series of live wind tunnel tests and computational fluid dynamic simulations to measure the power output, torque fluctuation, and wake region turbulence of this type of turbine. It compared a helical VAWT with a straight bladed VAWT of the same dimensions. In addition, simulations were used to examine the turbulence in the wake region of the turbines as well as the torque fluctuation produced in the center shaft. The results showed the helical design was found to have an improvement in the power output compared to the straight bladed design and showed improved self-starting capabilities. From the CFD analysis, the helical design did not have any significant improvement in velocity recovery or in the torque fluctuation, and the helical design did only show a slight improvement in the wake region turbulence, which can translate into some noise reduction. The results of this research demonstrate how adding a helical angle to a Darrieus VAWT design improves multiple characteristics compared to its straight bladed counterpart

Supporting regional growth from the higher education community: the Energy Coast Campus Programme in West Cumbria

West Cumbria is a predominantly rural, but post-industrial region undergoing a transition from one that has been dominated by heavy industry over a 200 year period. The regional economy has latterly been dominated by one of the world’s largest nuclear technology hubs, which continues to influence the structure of the economy. The region has aspirations to evolve a high technology manufacturing base, with a continued strong role for nuclear, but with a more diversified economy, including an expanded focus on low carbon and renewable energy generation. The region has aspirations to evolve a high technology manufacturing base, with a continued strong role for nuclear, but with a more diversified economy. As part of this strategy, a large investment has been made to build a higher education community in this largely rural area, to support its strategic objectives to promote innovation through applied research, research demonstration, enterprise, business support, skills and training and other transformational actions. Three case studies are described in detail: the Cumbrian Centre for Health Technologies (CaCHeT), the Sustainable Energy Technology Group and the Knowledge Action Network (KAN). The lessons learned are evaluated and presented, with details of future plans

The design and optimization of sustainable biopolymer-based adsorbents for the removal of a model aromatic naphthenic acid from aqueous solution

During the extraction of bitumen from the Alberta oil sands, a wide range of contaminants are concentrated in oil sands process-affected water (OSPW), among which is a family of organic carboxylic acids known collectively as naphthenic acids (NAs). NAs have shown to be both corrosive toward process equipment and acutely toxic toward a number of aquatic organisms. Therefore, for oil sands producers to either recycle OSPW or reintroduce it back into the environment, the concentration of NAs must be reduced to acceptable levels. Adsorption is one technique that has been investigated for their removal. This thesis reports on the removal of a model aromatic NA from aqueous solution using sustainable quaternized chitosan hydrogel adsorbents. Using optimized processing conditions to prepare the adsorbent material, an adsorption efficiency of 315 mg g-1 was observed. The kinetic and equilibrium adsorption characteristics were investigated by performing several batch adsorption experiments under a range of conditions. To improve the compressive strength of the hydrogel, cellulose nanocrystals (CNC) and quaternized cellulose nanocrystals (QCNC) were incorporated into the adsorbent formulation. Improvements in compressive strength of up to 179% were observed. However, this improvement was coupled with reductions in the efficiency of model NA adsorption. To the best of our knowledge, this work is one of very few studies to investigate the adsorption of NAs using polymeric resins and is the first to report the use of biopolymer based hydrogels and nanocomposite hydrogels for this application. When compared to other adsorbent materials reported in the literature, the adsorption efficiency of the presently reported material was on par if not superior

Interpreting institutional architecture : the long lives and layered meanings of Ireland's asylums

Ireland’s asylum network was remarkable for its early inception, peak extent and relative longevity, yet it was merely one element of the nation’s architecture of containment. Ireland’s health, education and welfare systems relied so heavily on residential institutions that by the late 1950s, over one-tenth of the population had direct experience of living within a ‘total institution’ at some point. But as contemporary society grapples with the implications of mass-institutionalisation, there is a real risk of oversimplifying complex histories and effacing earlier readings. This thesis is based on the premise that the close study of buildings and landscapes over the longue durée, from conception to ‘afterlife,’ can help to recover the layers of meaning with which successive generations imbued them. Asylum sponsors encoded their buildings with multiple messages for different audiences, but later generations were influenced less by a founding vision than by the conditions of their continuing service, as recorded in patterns of alteration and maintenance, of neglect and demolition. I focus on the metropolitan asylums of Dublin and Cork cities as my core case studies, in the context of a growing religious and voluntary sector which came to dominate the Irish institutional landscape. Along the way, I discuss themes of civic pride and architectural grandeur, local and national politics, finance and governance, voluntary and statutory initiatives. In drawing together these original geographic, temporal and contextual strands, I challenge the value judgements employed in current practices of architectural conservation and cultural heritage, which despite claiming greater concern for social values, paradoxically perpetuate the elite and sometimes repressive values embodied in the enduring divide between pauper and polite spaces. Understanding the long and contingent lives of buildings runs contrary to architectural history’s fascination with founding ideas, but is essential to recovering the evolving social meanings of architecture

Impact of Mandatory Diversity Training: Lessons from a Private University

Attendance at diversity training programs is often dictated by management, and participants find themselves caught between their genuine desire to broaden their understanding of the subject and resentment at being forced to do so. The outcomes of these mandatory training programs have not been systematically assessed. This study looks at the cognitive, attitudinal, and behavioral impacts of attending such a program and finds valuable lessons learned and cautious room for optimism

Progress Toward Affordable High Fidelity Combustion Simulations Using Filtered Density Functions for Hypersonic Flows in Complex Geometries

Significant progress has been made in the development of subgrid scale (SGS) closures based on a filtered density function (FDF) for large eddy simulations (LES) of turbulent reacting flows. The FDF is the counterpart of the probability density function (PDF) method, which has proven effective in Reynolds averaged simulations (RAS). However, while systematic progress is being made advancing the FDF models for relatively simple flows and lab-scale flames, the application of these methods in complex geometries and high speed, wall-bounded flows with shocks remains a challenge. The key difficulties are the significant computational cost associated with solving the FDF transport equation and numerically stiff finite rate chemistry. For LES/FDF methods to make a more significant impact in practical applications a pragmatic approach must be taken that significantly reduces the computational cost while maintaining high modeling fidelity. An example of one such ongoing effort is at the NASA Langley Research Center, where the first generation FDF models, namely the scalar filtered mass density function (SFMDF) are being implemented into VULCAN, a production-quality RAS and LES solver widely used for design of high speed propulsion flowpaths. This effort leverages internal and external collaborations to reduce the overall computational cost of high fidelity simulations in VULCAN by: implementing high order methods that allow reduction in the total number of computational cells without loss in accuracy; implementing first generation of high fidelity scalar PDF/FDF models applicable to high-speed compressible flows; coupling RAS/PDF and LES/FDF into a hybrid framework to efficiently and accurately model the effects of combustion in the vicinity of the walls; developing efficient Lagrangian particle tracking algorithms to support robust solutions of the FDF equations for high speed flows; and utilizing finite rate chemistry parametrization, such as flamelet models, to reduce the number of transported reactive species and remove numerical stiffness. This paper briefly introduces the SFMDF model (highlighting key benefits and challenges), and discusses particle tracking for flows with shocks, the hybrid coupled RAS/PDF and LES/FDF model, flamelet generated manifolds (FGM) model, and the Irregularly Portioned Lagrangian Monte Carlo Finite Difference (IPLMCFD) methodology for scalable simulation of high-speed reacting compressible flows

Supporting regional growth from the higher education community: the Energy Coast Campus Programme in West Cumbria

West Cumbria is a predominantly rural, but post-industrial region undergoing a transition from one that has been dominated by heavy industry over a 200 year period. The regional economy has latterly been dominated by one of the world?s largest nuclear technology hubs, which continues to influence the structure of the economy. The region has aspirations to evolve a high technology manufacturing base, with a continued strong role for nuclear, but with a more diversified economy, including an expanded focus on low carbon and renewable energy generation. The region has aspirations to evolve a high technology manufacturing base, with a continued strong role for nuclear, but with a more diversified economy. As part of this strategy, a large investment has been made to build a higher education community in this largely rural area, to support its strategic objectives to promote innovation through applied research, research demonstration, enterprise, business support, skills and training and other transformational actions. Three case studies are described in detail: the Cumbrian Centre for Health Technologies (CaCHeT), the Sustainable Energy Technology Group and the Knowledge Action Network (KAN). The lessons learned are evaluated and presented, with details of future plans