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.

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.

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.

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.

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.

Dissertation (MTech (Mechanical Engineering))--Cape Peninsula University of Technology, 2011 / This paper presents the development of a data collection system for a small unmanned Aerial Vehicle (UAV) flight. The following three facets comprise of a UAV system: (1) a UAV aircraft; (2) onboard avionics; and (3) a ground control station subsystem (Taha et al., 2010:1). In this project, the UAV aircraft is based on the low-cost autonomous quad-rotator system named “Arducopter Quad”, where the onboard avionic system utilizes both an ArduPilot Mega (APM) on-board controller and IMU sensor shield, while the “Mission Planner” software operates as GCS software to gather essential flight data (Xiang & Tian, 2011:176). The approach provides the UAV system structure and both hardware and software with a small UAV data collection system, which is examined throughout the study. And introduce the concept of Arducopter dynamics for better understanding with its flight control. The study also considers the communication process between the UAV and the ground control station. The radio wave is an important aspect in the UAV data collection system (Austin, 2010:143). The literature review introduced the basis of the radio wave in respect of its travelling speed, and its characteristics of propagation, including how different frequencies will affect radio wave propagation. The aim of this project was to develop a platform for a small UAV real-time data collection system. The pendulum system was involved to simulate the “Roll” movement of the small UAV, while real-time IMU sensor data was successfully collected at ground control station (GCS), both serial communication and wireless communication, which was applied in the data collection process. The microwave generator interference test proves that the 2.4 GHz XBee module is capable of establishing reliable indoor communication between the APM controller and the GCS. The work of this project is towards development of additional health monitoring technology to prevent the safety issue of the small UAV. The data collection system can be used as basis for the future research of real-time health monitoring for various small UAVs.

Thesis (DTech(Mechanical Engineering))--Cape Peninsula University of Technology, 2013 / The environment is polluted by many gases of which carbon dioxide is one of them and unfortunately during the emission of carbon dioxide, oxygen, which is very important for keeping all species alive, is depleted. Increased industrial activities led to more emission of carbon dioxide and ultimately global warming arose as a result of the greenhouse effect. Global warming has resulted with high temperatures and carbon dioxide production in the atmosphere and it was necessary to come up with mathematical modelling to investigate processes that may try to reduce temperature rise, carbon dioxide emission and oxygen depletion in a stockpile of combustible material. The work done in this thesis considered three differential equations, first for temperature behaviour, second for oxygen depletion and third for carbon dioxide emission. The three equations were solved simultaneously for a reactive slab of combustible material. An exothermic reaction in a stockpile of combustible material results due to the reaction of oxygen with reactive hydrocarbon material and the products are usually heat and carbon dioxide. A detailed discussion on this part is given in chapter 1, and also some definitions of terms applied in this work, together with literature review, statement of problem, aim of the study, objectives of the study and methodology are part of the chapter. In chapter 2, the nonlinear partial differential equations governing the process are derived.

Thesis submitted in fulfillment of the requirements for the degree Doctor of Technology: Mechanical Engineering Cape Peninsula University of Technology, 2013 / Fluid flow through a porous channel and cylindrical pipe walls are important area of research due to its wide applications in transpiration cooling, gaseous diffusion technology, cooling of rocket, mechanized irrigation and filtration processes. It is therefore necessary to examine the effect of Navier slip, combined effects of buoyancy forces and variable viscosity on the entire flow structure. Analyzing the magneto- hydrodynamics (MHD) of unsteady flow with buoyancy effect and also investigate numerically the entropy generation in an unsteady flow through porous pipe. We have also examined the thermal stability and entropy generation in the system. The problems were investigated theoretically using appropriate mathematical models for both transient and steady state scenario. Both analytical techniques and numerical methods are employed to tackle the model nonlinear equations derived from the law of conservation of mass, momentum and energy balance. Some definitions of terms to come across and introduction to fluid flow are given in chapter 1, together with literature reviews, statement of problem and objectives of the study. Chapter 2 lays the foundation for basic fundamental equations governing fluid flow. In chapter 3, the combined effect of suction/injection and asymmetric Navier slip on the entropy generation rate for steady flow of an incompressible viscous fluid through a porous channel subjected to different temperature at the walls are investigated. Chapter 4 analyze combined effects of buoyancy forces together with Navier slip on the entropy generation in a vertical porous channel wall with suction/injection wall. Analysis of MHD unsteady flow through a porous pipe with buoyancy effects are carried out in chapter 5, while chapter 6 investigates numerically entropy generation of unsteady flow through a porous pipe with suction and chapter 7 gives concluding remarks.

Thesis submitted in fulfilment of the requirements for the degree Doctor of Technology: Design in the Faculty of Informatics and Design at the Cape Peninsula University of Technology, 2012 / The aim of the research is to explore design education and designing as social practice; working with and for others to inform a more sustainable and meaningful future. Ways in which the lived experience of participants in the discipline of design, in the culturally diverse university and community contexts can be harnessed for social benefit, are interrogated. Themes are explored around the value of different world views and forms of knowing in design education to inform design research, in order to extend the knowledge paradigm to include lived experience not only as site of knowledge formation, but also of wisdom acquisition. The thesis presents an amalgamation of professional practice, creative practice and narrative set in qualitative research methods appropriate to the designer and artist who desire to work with lived experience in the academic context. Lived experience informs all we do and each educational event and encounter ought to be appraised and responded to in a contextually sensitive way. An important aspect flowing from this amalgamation is the recognition and analysis of the coexisting relationships of the roles inhering in the educator and the student. In order to immerse oneself in research and teaching, all aspects of the process have to be lived and filtered through the senses. This implies resisting abstractions by grounding research, teaching, design and making in the experience of the moment. The original contribution of this research then, is the synthesis of design, art and narrative writing that accompanied in a parallel line, the academic writing process to culminate in this design folio — a testament to grounding the research project in practice. Pedagogical approaches and lived experience embodied as recontextualised expressions in design teaching, supervision and creative practice, are presented in the folio. The boundaries of qualitative methods were tested with narrative and life writing, autoethnography, poetry, studio observations, extensive journalling, drawing, photography and printmaking processes. The results showed that a phenomenology of the senses in creative work, and locating the designer in her or his biography, is where original and imaginative design resides. Social and cultural aspects are some of the foundation stones of design education and ought to be informants of the creative process until the finish. Furthermore, authentic openness is required in supervision and teaching to facilitate deep listening, interpretation, intuition and “in-seeing” in educational encounters. Finally, being an active creative practitioner in design teaching is as important if not more important than content knowledge in that discipline, since the active practitioner “becomes” the Other through the collective dimension of design work.

THESIS Submitted in fulfilment of the requirements for the degree MAGISTER TECHNOLOGIAE in INFORMATION TECHNOLOGY in the FACULTY OF BUSINESS INFORMATICS at the CAPE PENINSULA UNIVERSITY OF TECHNOLOGY 2005 / The Internet has become the fastest growing technology the world has ever seen. It also has the ability to permanently change the face of business, including e-business. The Internet has become an important tool required to gain potential competitiveness in the global information environment. Companies could improve their levels of functionality and customer satisfaction by adopting e-commerce, which ultimately could improve their long-term profitability. Those companies who do end up adopting the use of the Internet, often fail to gain the advantage of providing a visible website. Research has also shown that even though the web provides numerous opportunities, the majority of SMMEs (small, medium and micro enterprises) are often ill equipped to exploit the web’s commercial potential. It was determined in this research project through the analysis of 300 websites, that only 6.3% of SMMEs in the Western Cape Province of South Africa appears within the top 30 results of six search engines, when searching for services/products. This lack of ability to produce a visible website is believed to be due to the lack of education and training, financial support and availability of time prevalent in SMMEs. For this reason a model was developed to facilitate the improvement of SMME website visibility. To develop the visibility model, this research project was conducted to identify potential elements which could provide a possible increase in website visibility. A criteria list of these elements was used to evaluate a sample of websites, to determine to what extent they made use of these potential elements. An evaluation was then conducted with 144 different SMME websites by searching for nine individual keywords within four search engines (Google, MSN, Yahoo, Ananzi), and using the first four results of every keyword from every search engine for analysis. Elements gathered through academic literature were then listed according to the usage of these elements in the top-ranking websites when searching for predetermined keywords. Further qualitative research was conducted to triangulate the data gathered from the literature and the quantitative research. The evaluative results provided the researcher with possible elements / designing techniques to formulate a model to develop a visible website that is not only supported by arrant research, but also through real current applications. The research concluded that, as time progresses and technology improves, new ways to improve website visibility will evolve. Furthermore, that there is no quick method for businesses to produce a visible website as there are many aspects that should be considered when developing “visible” websites.