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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Modelling the dispersion of SO2 emissions from the chevron (Cape Town) oil refinery using the US EPA dispersion models AERMOD and CALPUFF

Mtiya, Khanyisa Siyakudumisa January 2013 (has links)
Thesis submitted in partial fulfilment of the requirements for the degree Master of Technology: Chemical Engineering in the Faculty of Engineering at the Cape Peninsula University of Technology 2013 / In South Africa, the Department of Environmental Affairs (DEA) under the National Environmental Management Act, 1998 (Act 107 of 1998) (“NEMA”) sets out a series of environmental management principles that apply to the interpretation and application of all legislation that may affect the environment. Since 1998, various specific environmental statutes that fall under the NEMA framework have been promulgated, including the National Environmental Management: Air Quality Act, Act 39 of 2004 (NEM: AQA).NEM:AQA provides norms and standards for all technical aspects of air quality management. The National Framework (Sections 7 and 8 of NEM:AQA) must provide mechanisms, systems and procedures to promote holistic and integrated air quality management through pollution prevention and minimisation at source, and through impact management with respect to the receiving environment, from local scale to international issues. Among other measures, the NEM:AQA (Section 9) requires the establishment of Ambient Air Quality Standards and Emission Standards. These standards were promulgated in December 2009 and March 2010 respectively. Air quality monitoring stations, which sample and analyse pollutant concentrations continuously, are a common method of assessing air quality in a region. But a few continuous monitors located in source given region or airshed are inadequate for assessing compliance with ambient air quality standards – they are only able to monitor concentrations at a fixed site, not through the entire region of impact. In contrast, the ambient air quality standards are applicable everywhere. Air quality models estimate ground level ambient concentrations throughout the modelling domain, and in principle (subject to proper validation) provide better estimates of area-wide concentrations and hence the basis for assessing compliance with air quality standards. The United States Environmental Protection Agency (US EPA) approved atmospheric air dispersion models AERMOD and CALPUFF were used in this thesis to predict the ground level concentrations of SO2 emitted from Chevron Refinery (Cape Town), for the year 2010. The modelling is validated by comparing measured ambient concentrations with modelled concentrations. The results showed AERMOD-modelled annual average values for 2010, based on refinery emissions only, are in good agreement with monitored values at the Table View and Bothasig sites, predicting the monitored values by -11% and +17% respectively. The 24-hr average values similarly are in good agreement with monitored values, on average over-predicting by 9% at Table View, although the fit of the day-to-day modelled vs monitored values is comparatively poor (R2=0.32); at the Bothasig site the corresponding values are - 36% and R2= 0.089. The AERMOD-modelled isopleths imply that the 2010 annual average concentrations exceeded the South African Standard of 50 μg/m3 in a small area in the immediate vicinity of the refinery. The hourly and 24-hourly average standard concentrations of 350μg/m3 and 125μg/m3 respectively are exceeded in significantly larger areas. The allowable exceedences for hourly and 24-hourly averages are also exceeded, implying that the hourly and 24-hourly standards were exceeded. CALPUFF-modelled average values for 2010, based on refinery emissions only, are in comparatively poor agreement with monitored values at the Table View and Bothasig sites, under-predicting the monitored values by -20% and -61% respectively. Since the AERMOD-modelled concentrations are in far better agreement with monitored concentrations, only AERMOD was used for further analysis. The Emission Standards promulgated in March 2010 included emission limit values for sulphur dioxide emitted from oil refineries. If the actual 2010 emission rates were adjusted downwards to match the emission standards (to be complied with from 1 April 2015), AERMOD modelling indicates that the annual, 24-hourly and hourly Ambient Air Quality Standards would not be exceeded. Based on this case study, the current Emission Standard for SO2 emissions from existing crude oil refineries is therefore coherent with the Ambient Air Quality Standards. Regulatory air dispersion modelling practices in South Africa are being standardised for model applications regulatory purposes and to ensure that dispersion modelling practices are undertaken in a compatible form to ensure that results from one dispersion model study can be compared directly to those from another. In this study both AERMOD and CALPUFF modelling complied with the draft South African guidelines for Air Quality Modelling, yet the CALPUFF- modelled outputs differed significantly from the monitored values. This emphasizes the importance of the inclusion of modelling validation in guidelines for modelling for regulatory purposes. The 2012 draft regulation should be amended to make validation of regulatory dispersion modelling compulsory rather than optional as per the draft.
102

Centrifugal pump derating non-Newtonian slurries: analysis of the viscosity to be used in the hydraulic institute method

Kalombo, Jean-Jacques Ntambwe January 2013 (has links)
Thesis (MTech (Chemical Engineering))--Cape Peninsula University of Technology, 2013 / Centrifugal pumps are the most commonly used pumps in slurry transport systems. The design of pumping systems dealing with liquids more viscous than water requires a reliable method of pump performance prediction for the pump selection. For Newtonian fluids, the Hydraulic Institute method is well established, but there is no generally accepted method for non-Newtonian fluids. Many authors have fallen back on using the Hydraulic Institute method for non-Newtonian fluids. This requires a constant viscosity while non-Newtonian fluid viscosity varies with the shear rate. The question arises: What viscosity should be used in this method for non-Newtonian fluids? Two approaches have been developed: the use of a Bingham plastic viscosity made by Walker and Goulas (1984) and the use of the apparent viscosity calculated using an “equivalent hydraulic pipe” diameter, designed by Pullum et al. (2007). Previous results obtained from these two approaches are not in agreement. Therefore, the aim of this study is to explore a suitable procedure to determine a representative non-Newtonian viscosity to be used in the Hydraulic Institute method to predict the pump performance. To achieve this goal, a set of data was experimentally obtained and the existing data were reused. Test work was conducted using the pump test rig in the Flow Process Research Centre at the Cape Peninsula University of Technology. A Warman 4/3 pump was tested, using four concentrations of kaolin suspension and three concentrations of CMC solution. Five pump speeds were chosen to run these tests: 1200, 1400, 1600, 1800, and 2000 rpm. An additional data set obtained by testing two submersible centrifugal pumps with eight concentrations of sludge, in Stockholm, Sweden, was also analysed. These sets of data were analysed firstly according to the Walker and Goulas (1984) approach and secondly according to the Pullum et al. (2007) approach. The use of the apparent viscosity led to the better pump head prediction. The results of this prediction were close to those obtained in the Pullum et al. (2007) work, and even better in some cases. On the other hand, the use of the Bingham plastic viscosity showed better pump efficiency prediction, although the Walker and Goulas (1984) efficiency prediction range was achieved only for one pump out of five. The apparent viscosity reflected the non-Newtonian behaviour but it could not represent alone the non-Newtonian viscosity because of the poor efficiency predictions and the sensitivity of the Pullum et al. (2007) approach to a change in viscosity. From the results of this work, it is advisable that the pump performance prediction be done using both apparent and Bingham plastic viscosity, the apparent viscosity for the head prediction and the Bingham plastic viscosity for the efficiency prediction.
103

Using rheometry for prediction the pumping characteristics of highly concentrated W/O emulsion explosives

Nkomo, Sithethi Espin January 2005 (has links)
Dissertation submitted in fulfilment of the requirements for the Masters Degree in Technology: Chemical Engineering in the Department of Chemical Engineering of Cape Peninsula University ofTechnology, 2005 / The emulsion used for this study is a new thermodynamically unstable multi-component waterin- oil (w/o) explosive type with an internal phase ratio of approximately 94%, i.e. far beyond the close packing limit of spherical droplets of 74%. Economic considerations and the ongoing need for continuous drilling, loading and blasting in the mining industry, has made long-distance pipeline transportation of these emulsion explosive systems a viable economic option. Presently, rheological characterization of emulsion explosives is well documented (Bampfield & Cooper, 1988, Utracki, 1980). However, very little or none has been done for this system, pertaining to the use of rheometry for prediction of pumping characteristics of these systems in long-distance pipeline transport. This Master's dissertation is devoted to develop rheological methods of testing, characterization and correlation in order to develop a basis for predicting the pumping characteristics of highly concentrated w/o emulsion explosives from rheometry. The literature and theory pertinent to the pipeline flow of high internal phase ratio emulsion explosives are presented, as well as the fundamentals of both concentric cylinder rheometry and pipe viscometry. The most relevant is the work of Bampfield and Cooper (1988), Utracki (1980) and Pal (1990). Two experimental test facilities were used for data collection. Pipeline experiments were done using an experimental test facility at African Explosives Limited (AEL), and rheometry was conducted at the Rheology Laboratory of the Cape Peninsula University of Technology Flow Process Research Centre. The AEL experimental test facility consisted of a four-stage Orbit progressive cavity pump, two fluid reservoirs, (a mixing tank and a discharge reservoir), five 45m HOPE (high density polyethylene) pipes of internal diameters of 35.9 mm, 48.1 mm, 55.9 mm, 65.9 mm and 77.6 mm pipes. The test work was done over a wide range of laminar flow rates ranging from 3 kg.min-I to 53 kg.min-I . Rheometry was done using a PaarPhysica MCR300 rheometer, and only standard rotational tests (i.e. flow curve) at 30 °c in controlled rate mode were done. Rheological characterisation was done using three rheological models, i.e. the Herschel-Bulkley, the Power Law and the Simplified Cross models. The coefficients obtained from these models were then used to predict pumping characteristics. The performances of these models were then evaluated by comparing the pipeline flow prediction to the actual pipeline data obtained from pipeline test experiments. It was found that the flow behaviour depicted by this explosive emulsion system was strongly non-Newtonian, and was characterized by two distinct regions of deformation behaviour, a lower Newtonian region of deformation behaviour in the shear rate region lower than 0.001 S-I and a strong shear thinning region in the shear rate range greater than 0.001 S-l. For all the models used for this study, it was evident that rheometry predicts the pumping characteristics of this high internal phase ratio emulsion reasonably well, irrespective of the choice of the model used for the predictions. It was also seen that the major difference between these models was in the lower shear rate domain. However, the Simplified Cross model was preferred over the other two models, since its parameter (the zero shear viscosity denoted by 110) can in general be correlated to the structure of the emulsion systems (i.e. mean droplet size, bulk modulus, etc.). Thus, structural changes induced by shearing (either inside the pump or when flowing inside a pipe) can be detected from changes in the value of the 110. The above statement implies that Tlo can be used as a quality control measure. Different pumping speeds were found to cause different degrees of shear-induced structural changes which were manifested by two opposing processes. These two opposing processes were the simultaneous coalescence and flocculation of droplets encountered at low rates of shear, and the simultaneous refinement and deflocculation of droplets encountered at high rates of shear. These two droplet phenomena were associated with a decrease or an increase in viscous effects, leading to both lower and higher viscous stresses and pumping pressures during pump start-up respectively.
104

Synthesis of zeolites from South African coal fly ash: investigation of scale-up conditions

Mainganye, Dakalo January 2012 (has links)
Thesis submitted in fulfilment of requirements for the degree Magister Technologiae: Chemical Engineering In the FACULTY OF ENGINEERING At the CAPE PENINSULA UNIVERSITY OF TECHNOLOGY, 2012 / The generation of electricity from coal in South Africa results in millions of tons of fly ash being produced each year. Less than 10 % of the fly ash generated is being used constructively and the remaining unused ash is currently inducing disposal and environmental problems. Intensive research on the utilisation of fly ash has been conducted either to reduce the cost of disposal or to minimise its impact on the environment. It has been shown that South African fly ash can be used as a feedstock for zeolite synthesis due to its compositional dominance of aluminosilicate and silicate phases. Most of the studies conducted on zeolite synthesis using South African fly ash are performed on small laboratory scale. Therefore, production of zeolites on an industrial/pilot plant scale would, in addition to producing a valuable product, help abate the pollution caused by the disposal of fly ash in the country. This research focuses on the investigation of the scale-up opportunity of zeolite synthesis from South African fly ashes with the view of understanding the effects of some reactor and operational parameters on the quality of the zeolite produced. Two types of zeolites (zeolite Na-P1 and zeolite A) were synthesised via two different routes in this study: (1) a two stage hydrothermal synthesis method (zeolite Na-P1) and (2) alkaline fusion prior to hydrothermal synthesis (zeolite A). The synthesis variables evaluated in this study were; the effect of impeller design and agitation rates during the aging step (zeolite Na-P1) using three different impellers (anchor, 4-flat-blade and Archimedes screw impeller) at three agitation speeds (150, 200 and 300 rpm), the effect of fly ash composition and solvents (water sources) on the phase purity of both zeolite Na-P1 and zeolite A, and the effect of the hydrothermal reaction time during the synthesis of zeolite Na-P1 using low amorphous phase fly ash i.e. aging time (12-48 hours) and hydrothermal treatment time (12-48 hours). The raw materials (fly ashes from Arnot, Hendrina, Tutuka, Lethabo and Matla power stations) and the synthesised zeolite product were characterised chemically, mineralogically and morphologically by X-ray fluorescence spectrometry, X-ray powder diffraction and scanning electron microscopy. Other characterisation techniques used in the study were 1) Fourier transform infrared spectroscopy to provide structural information and also monitor the evolution of the zeolite crystals during synthesis and 2) inductively coupled plasma atomic emission (ICP-AES) and mass spectrometry for multi-elemental analysis of the synthesis solution and the solvents used in this study. The experimental results demonstrated that the phase purity of zeolite Na-P1 was strongly affected by agitation and the type of impeller used during the aging step of the synthesis process. A high crystalline zeolite Na-P1 was obtained with a 4-flat-blade impeller at a low agitation rate of 200 rpm. Although a pure phase of zeolite Na-P1 was obtained at low agitation rates, the variation in the mineralogy of the fly ash was found to affect the quality of the zeolite produced significantly. The results suggested that each batch of fly ash would require a separate optimisation process of the synthesis conditions. Therefore, there is a need to develop a database of the synthesis conditions for zeolite Na-P1 based on the fly ash composition. As a consequence, the scale-up synthesis of zeolite Na-P1 would require step-by-step optimisation of the synthesis conditions, since this zeolite was sensitive to the SiO2/Al2O3 ratio, agitation and the mineralogy of the fly ash. On the other hand, zeolite A synthesis had several advantages over zeolite Na-P1. The results suggested that a pure phase of zeolite A can be produced at very low reaction temperature (i.e. below 100 °C, compared to 140 °C for zeolite Na-P1), shorter reaction times (i.e. less than 8 hours compared to 4 days for zeolite Na-P1), with complete dissolution of fly ash phases and more importantly less sensitive to the SiO2/Al2O3 ratio of the raw materials. The zeolite A synthesis process was found to be more robust and as a result, it would be less rigorous to scale-up despite the energy requirements for fusion. This study showed for the first time that different impeller designs and agitation during the aging step can have a profound impact on the quality of the zeolite produced. Therefore, it is not only the hydrothermal synthesis conditions and the molar regime but also the dissolution kinetics of the feedstock that influence the outcome of the zeolite synthesis process. This study has also shown for the first time that a pure phase of zeolite A can be synthesised from various sources of South African fly ash containing different mineralogical and chemical compositions via the alkali fusion method under the same synthesis conditions. Therefore, the effective zeolitisation of fly ash on a large scale would assist to mitigate the depletion of resources and environmental problems caused by the disposal of fly ash.
105

The impact of the attacks on 11 September 2001 on the World Trade Centre on the tourism industry in the Western Cape: a case study

Von Wielligh, Jacobus Petrus January 2009 (has links)
Mini Thesis submitted in partial fulfillment of the requirements for the M Tech: Business Administration in the FACULTY of BUSINESS at the CAPE PENINSULA UNIVERSITY OF TECHNOLOGY 2009 / The tourism industry is subject to the perception of the tourist whether the chosen destination is perceived as a safe destination. No tourist wants their planned vacation interrupted by acts of violence, placing his and his family’s lives in danger. The attacks on the World Trade Centre in September 2001, has changed the way we travelled for ever. The tourism industry realized that no destination, no mater how far removed from the so called “hot spots” (areas of conflict), could be seen as a safe destination. Acts of violence can occur at any destination at any time. This attack also had a significant impact on the way tourist travel and how they plan their vacations. Added security at all international airports were upgraded to ensure passenger safety, but with that came delays and longer check in times. All of these have a negative impact on the airlines. Tourist also opted for the more safer destinations, those that are removed form potential conflict areas. In the months following directly after the attacks, most popular destination experienced a significant decline in tourist numbers. Major airline across the globe also lost out on revenue, with some of them being forced to close their operations. This had an impact on employment figures in the tourism industry. The attacks however had a positive side to it as well. Some destinations benefited in tourism numbers, due to the fact that these destinations were seen a safe areas to spend one’s vacation at. South Africa, and in particular the Western Cape, is one of these areas that benefited with increasing tourism numbers, due to its status as a safe destination.
106

Business relationships as a driver of success for SMMEs in Hout Bay

Xesha, Dumisani January 2012 (has links)
Dissertation submitted in fulfillment of the requirements for the degree Master of Technology: Business Administration (Entrepreneurship) In the faculty of Business At Cape Peninsula University of Technology, 2012 / As markets and businesses become more dynamic, administrative and technical skills of entrepreneurs are no longer sufficient to deal with the complexities of modern business management. Businesses wishing to compete at a world-class level must improve the way they interact and deal with the demands of the different stakeholders. One way to do this, is to develop and sustain relationships amongst the network of stakeholders that have the potential to assist in their development, survival and growth. Studies suggest that even if a business does not want to use relationships as a strategy for competing it still has to consider the complexity and connectedness of the marketplace in which it operates. The variety of networks any business finds itself in, requires a strategic perspective, at least to deter it from failing. This study attempted to outline the role played by business relationships in the success of businesses in the communities of Imizamo Yethu, Harbour and the Central Business District in Hout Bay. This research was designed to outline the importance of creating and maintaining a relationship with all stakeholders. The overall approach of this research is guided by the principle that the success of businesses in these communities is driven by the interrelationship between the business owner (as the decision-maker), the employees and the surrounding households (the immediate customers). The research provides guidelines for the business owners on the attributes they should possess in order to maintain these relationships. A relationship survey was designed for the three groups of participants. The information gained from this survey enabled the researcher to report on the nature of these relationships and the role these relationships play in the success of businesses in Hout Bay. The findings of the research were positive: meaning good relationships do exist in the majority of businesses in the community. The comments provided by the owners, staff and surrounding community, together with literature references, provided the researcher the opportunity to discuss the role these relationships have played in achieving success.
107

Evaluation criteria for selected administrative and support systems in South African higher education institutions

Weideman, Renee January 2008 (has links)
Dissertation prepared in fulfilment of the requirements for the degree of Magister Technologiae (Quality) CAPE PENINSULA UNIVERSITY OF TECHNOLOGY 2008 / The aim of this research is to identify criteria for the evaluation of support systems applicable to public higher education institutions from a limited international and national perspective. The objectives of the research are to identify the criteria available from existing and related fields through a literature review and to validate the evaluation criteria using an empirical study. The existing literature describes the relevant academic processes, but very little has been written on criteria for evaluating support systems. The research for this study attempts to address this deficiency. The criteria from the Coetzee Model were used as a basis for this research and other models in the existing literature were also referred to, including the Baldrige National Quality Program for Education Criteria, ISO 9001:2000, European Foundation Quality Model and the South African Excellence Model. This research also draws on information deemed important by the Higher Education Quality Committee and the South African Qualifications Authority. Both qualitative and quantitative data collection methods were used in the investigation. The research instruments used included questionnaires and interviews. Questionnaires were distributed to all public universities, universities of technology, and one technikon in South Africa. The results of the study revealed that most respondents agreed with the generic criteria against which units should be evaluated; namely “leadership”, “strategic goals and performance indicators”, “resourcing and funding”, “policies and procedures” and “self-evaluation guidelines”. Statistical analysis was done on the criteria. The two main findings of the research showed that the first five generic criteria were valid and reliable and that there was good internal consistency among the items in each of these criteria, which confirms that the results were valid. It is recommended that for future research, the study should be expanded to support units in higher education not included in this study. The suitability of generic criteria and the development of further specific criteria should be determined. Quality-related arrangements for community engagement, where appropriate, should be adequately resourced and monitored for each unit. Once evaluations and surveys have been conducted on support units using the criteria, the process of benchmarking should be used for preventing potential problems and improving results. KEYWORDS Administration, audit, core processes, criteria, customer, evaluation, higher education, key performance indicators, principles, quality, support processes, systems
108

Organisational transformation using total quality management and ISO 9000

Nabe, Percival Mvuyisi January 2008 (has links)
To be submitted in partial fulfilment of the requirements for the degree MAGISTER TECHNOLOGIAE in Quality Faculty of Engineering CAPE PENINSULA UNIVERSITY OF TECHNOLOGY 2008 / Engineering by its very nature is associated with quality processes. Ineffective processes have the potential to jeopardize the chances of providing consistently, products that meet customer and applicable regulatory requirements. By implication, this senario also calls for organizational transformation. SA Five Engineering (Pty) Ltd (SAF), which will serve as the target organization for this research study has in the past year suffered numerous complaints of poor products as a result of ineffective processes, impacting on production quality. Both 150 9000 and the concept of Total Quality Management have the potential to mitigate ineffective processes within SAF. The key research objective with this research study, is to recommend how to improve ineffective processes and the competitive advantage of SAF through improved products. Furthermore, to analyze the business organization in order to determine the extent to which Total Quality Management principles are deployed with the aim of developing a model, which will serve as a benchmark for sustained improvement. The research problem deals with ineffective processes within SAF which impacts adversely on delivery of quality products and services. The research design and methodology to be conducted within the ambit of this research study is applied research, as applied research is designed to apply its findings to solve a specific existing problem. The research will furthermore fall in the social world as the research relates to a structured business research study pertaining to how things are, and why. The research will be conducted from both an empirical and theoretical research paradigm, using a survey for the purpose of data collection. The research method that will be applied within the context of this research study will be a case study research.
109

Identification of flow patterns for coarse particles transported in a non-Newtonian carrier using electrical resistance tomography

Kabengele, Kantu January 2012 (has links)
A dissertation submitted to the Faculty of Engineering, Cape Peninsula University of Technology, Cape Town, in partial fulfilment of the requirements for the MTech Degree in Mechanical Engineering 2012 / Flow features provide considerable guidance for the rational selection of techniques to predict hydraulic behaviour and for suitable operating conditions for pipelines. Traditionally, water was used to transport coarse particles, and it was necessary to operate at velocities at which the flow was turbulent in order to avoid blockage. Consequently the friction losses were too high for economic operation. In addition, wear on pipes, fittings and pumps presented serious problems. Nowadays, it is well established that it is possible to operate at very high solids concentration in a heavy vehicle (carrier fluid). Similar solids throughputs may be achieved at very much lower velocities by operating in the laminar flow regime. This results not only in lower power requirement, but it also reduces wear and water consumption. In spite of these potential benefits, only a few studies dealing with the transport of coarse particles in heavy media have been reported. Since the distinction between different flow patterns is of paramount importance for modelling purposes, as equations are flow pattern dependent, and given the importance of avoiding excessive wear of pipes at low and high velocities, the present work was carried out in the context of dense or non-Newtonian carrier fluid. This project comprised analysis of existing data acquired at the Flow Process and Rheology Centre of the Cape Peninsula University of Technology. Kaolin in the range of 6% to 15% volumetric concentration was used as a carrier fluid and coarse material in the range of 10% to 30% volumetric concentration was simulated by silica sand ranging in size from 1 mm to 3 mm. For the purpose of this study flow patterns derived from resistance curves for various mixtures, particle concentrations, particle grading and flow conditions were compared with “concentration profiles” and images obtained from electrical resistance tomography (ERT). It appeared from this work that the sand concentration does not change the flow pattern but increases or reduces the pressure gradients depending on the case. The concentration of kaolin carrier can change the flow patterns from layered to homogeneous flow, inducing an increase in total pressure gradients as it increases. Flow patterns obtained from ERT compared reasonably well with those derived from pressure gradients profiles. The transition velocities from layered to heterogeneous flow obtained from both methods were similar, especially for low and moderate carrier concentrations. As the kaolin carrier concentration or as the sand concentration increased it became more difficult to distinguish the transition velocity between heterogeneous and layered flow. More work is still needed to improve the ERT instrument and its image reconstruction software.
110

Comparison of fixed diameter and variable diameter wind turbines driving a permanent magnet hub motor

Pietrangeli, Sven January 2012 (has links)
Thesis submitted in fulfilment of the requirements for the degree MAGISTER TECHNOLOGIAE: Mechanical Engineering in the FACULTY OF ENGINEERING at the CAPE PENINSULA UNIVERSITY OF TECHNOLOGY, 2012 / The amount of power a horizontal axis wind turbine (HAWT) can produce is determined by two main factors, wind velocity and rotor swept area. Theory dictates that the power production of a horizontal wind turbine is related to the cube of wind velocity and the square of the turbine diameter (or radius). The power produced at any given time is thus dependent on of the wind velocity and the rotor swept area of the turbine. Wind is variable in availability and consistency. Very little can be done to effect the wind velocity passing through the turbine rotor area and its effect is minimal. Thus understandably if more power is required, from the same wind velocity, the rotor diameter must be increased. A variable length blade can adapt lengthwise to accommodate low wind velocities and similarly high wind velocities during extreme conditions, thus increasing the operational time and power production of the turbine. The work undertaken in this thesis is a comparative study between standard design, fixed length blades to that of a modified design, variable length blade. The project entailed the design and development of small diameter HAWT blades and experimental testing. The turbine blades were designed using applicable theory and manufactured from available materials. For the experiments, the turbine was mounted on a vehicle and driven at various speeds. Due to size limitations, no dynamic adaption was done during testing. The variable length design blade was obtained by cutting increments off. The results obtained from each test were compared at corresponding points and conditions. Final interpretation of results lead to the conclusion that by increasing or decreasing the turbine blade length the area of turbine energy capture can be adjusted to affect the amount of power produced. Additional benefits included, force reduction during extreme operating conditions, extended production period for the turbine and a mechanical start up method during low wind speeds. The financial feasibility did not form part of the scope of this thesis and the technical feasibility of the concept can be thoroughly addressed in future research.

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