33 resultados para Industrial and Product Design
em Aston University Research Archive
Resumo:
The objective of this work was to design, construct and commission a new ablative pyrolysis reactor and a high efficiency product collection system. The reactor was to have a nominal throughput of 10 kg/11r of dry biomass and be inherently scalable up to an industrial scale application of 10 tones/hr. The whole process consists of a bladed ablative pyrolysis reactor, two high efficiency cyclones for char removal and a disk and doughnut quench column combined with a wet walled electrostatic precipitator, which is directly mounted on top, for liquids collection. In order to aid design and scale-up calculations, detailed mathematical modelling was undertaken of the reaction system enabling sizes, efficiencies and operating conditions to be determined. Specifically, a modular approach was taken due to the iterative nature of some of the design methodologies, with the output from one module being the input to the next. Separate modules were developed for the determination of the biomass ablation rate, specification of the reactor capacity, cyclone design, quench column design and electrostatic precipitator design. These models enabled a rigorous design protocol to be developed capable of specifying the required reactor and product collection system size for specified biomass throughputs, operating conditions and collection efficiencies. The reactor proved capable of generating an ablation rate of 0.63 mm/s for pine wood at a temperature of 525 'DC with a relative velocity between the heated surface and reacting biomass particle of 12.1 m/s. The reactor achieved a maximum throughput of 2.3 kg/hr, which was the maximum the biomass feeder could supply. The reactor is capable of being operated at a far higher throughput but this would require a new feeder and drive motor to be purchased. Modelling showed that the reactor is capable of achieving a reactor throughput of approximately 30 kg/hr. This is an area that should be considered for the future as the reactor is currently operating well below its theoretical maximum. Calculations show that the current product collection system could operate efficiently up to a maximum feed rate of 10 kg/Fir, provided the inert gas supply was adjusted accordingly to keep the vapour residence time in the electrostatic precipitator above one second. Operation above 10 kg/hr would require some modifications to the product collection system. Eight experimental runs were documented and considered successful, more were attempted but due to equipment failure had to be abandoned. This does not detract from the fact that the reactor and product collection system design was extremely efficient. The maximum total liquid yield was 64.9 % liquid yields on a dry wood fed basis. It is considered that the liquid yield would have been higher had there been sufficient development time to overcome certain operational difficulties and if longer operating runs had been attempted to offset product losses occurring due to the difficulties in collecting all available product from a large scale collection unit. The liquids collection system was highly efficient and modeling determined a liquid collection efficiency of above 99% on a mass basis. This was validated due to the fact that a dry ice/acetone condenser and a cotton wool filter downstream of the collection unit enabled mass measurements of the amount of condensable product exiting the product collection unit. This showed that the collection efficiency was in excess of 99% on a mass basis.
Resumo:
Product design and sourcing decisions are among the most difficult and important of all decisions facing multinational manufacturing companies, yet associated decision support and evaluation systems tend to be myopic in nature. Design for manufacture and assembly techniques, for example, generally focuses on manufacturing capability and ignores capacity although both should be considered. Similarly, most modelling and evaluation tools available to examine the performance of various solution and improvement techniques have a narrower scope than desired. A unique collaboration, funded by the US National Science Foundation, between researchers in the USA and the UK currently addresses these problems. This paper describes a technique known as Design For the Existing Environment (DFEE) and an holistic evaluation system based on enterprise simulation that was used to demonstrate the business benefits of DFEE applied in a simple product development and manufacturing case study. A project that will extend these techniques to evaluate global product sourcing strategies is described along with the practical difficulties of building an enterprise simulation on the scale and detail required.
Resumo:
This thesis presents a study of the sources of new product ideas and the development of new product proposals in an organisation in the UK Computer Industry. The thesis extends the work of von Hippel by showing how the phenomenon which he describes as "the Customer Active Paradigm for new product idea generation" can be observed to operate in this Industry. Furthermore, this thesis contrasts his Customer Active Paradigm with the more usually encountered Manufacturer Active Paradigm. In a second area, the thesis draws a number of conclusions relating to methods of market research, confirming existing observations and demonstrating the suitability of flexible interview strategies in certain circumstances. The thesis goes on to demonstrate the importance of free information flow within the organisation, making it more likely that sought and unsought opportunities can be exploited. It is shown that formal information flows and documents are a necessary but not sufficient means of influencing the formation of the organisation's dominant ideas on new product areas. The findings also link the work of Tushman and Katz on the role of "Gatekeepers" with the work of von Hippel by showing that the role of gatekeeper is particularly appropriate and useful to an organisation changing from Customer Active to Manufacturer Active methods of idea generation. Finally, the thesis provides conclusions relating to the exploitation of specific new product opportunities facing the sponsoring organisation.
Resumo:
This thesis is related to the subject of technical innovation, specifically to the activity of design in microenterprises operating in less industrialised economies. Design here is understood as a process, which is not the sole domain of formally trained categories such as engineers, architects or industrial designers. The 'professional boundary' discussion in this investigation is perceived as secondary as, in this context, products are designed, copied or adapted by workers, entrepreneurs themselves, or directly by the poor community. Design capacity at this level is considered to be important both in relation to the conception of capital and consumer goods and to the building up of technical knowledge. Although professional design emerged in Latin America little over three decades ago, this activity has remained marginalised throughout industry. Design activity tends to be concentrated in some product categories in the formalised industrial sector. For microenterprises operating informally, industrial design appears to be unknown. The existing literature pays little attention to 'informal design' capacity. Other areas of knowledge, such as development economies, recognise the importance of microenterprises and technological capability but neglect the potential role of industrial design in small manufacturing units. The management literature, though it focuses on technical innovation and design, has also paid little attention to 'informal design'. In less industrialised economies this neglect is felt by the lack of programmes specifically tailored to create or stimulate 'informal design'. There is a need for recognition of 'informal design' capacity and for the implementation of programmes which specifically target design as a central activity in the manufacturing firm, independent of their size and technological capability. Addressing 'design by the poor for the poor', requires a down-to-earth approach.
Resumo:
This study explores the ongoing pedagogical development of a number of undergraduate design and engineering programmes in the United Kingdom. Observations and data have been collected over several cohorts to bring a valuable perspective to the approaches piloted across two similar university departments while trialling a number of innovative learning strategies. In addition to the concurrent institutional studies the work explores curriculum design that applies the principles of Co-Design, multidisciplinary and trans disciplinary learning, with both engineering and product design students working alongside each other through a practical problem solving learning approach known as the CDIO learning initiative (Conceive, Design Implement and Operate) [1]. The study builds on previous work presented at the 2010 EPDE conference: The Effect of Personality on the Design Team: Lessons from Industry for Design Education [2]. The subsequent work presented in this paper applies the findings to mixed design and engineering team based learning, building on the insight gained through a number of industrial process case studies carried out in current design practice. Developments in delivery also aligning the CDIO principles of learning through doing into a practice based, collaborative learning experience and include elements of the TRIZ creative problem solving technique [3]. The paper will outline case studies involving a number of mixed engineering and design student projects that highlight the CDIO principles, combined with an external industrial design brief. It will compare and contrast the learning experience with that of a KTP derived student project, to examine an industry based model for student projects. In addition key areas of best practice will be presented, and student work from each mode will be discussed at the conference.
Resumo:
Productivity growth has long been associated with, among other things, contestability of markets which, in turn, is dependent on the ease with which potential competitors to the incumbent firms can enter the product market. There is a growing consensus that in emerging markets regulatory and institutional factors may have a greater influence on a firm's ability to enter a product market than strategic positions adopted by the incumbent firms. We examine this proposition in the context of India where the industrial policies of the 1980s and the 1990s are widely believed to be pro-incumbent and pro-competition, respectively, thereby providing the setting for a natural experiment with 1991 as the watershed year. In our analysis, we also take into consideration the possibility that the greater economic federalism associated with the reforms of the 1990s may have affected the distribution of industrial units across states after 1991. Our paper, which uses the experiences of the textiles and electrical machinery sectors during the two decades as the basis for the analysis, finds broad support for both these hypotheses.
Resumo:
This study examines the effect of individual character types in design teams through case studies at ARUP associates and five United Kingdom university design degree programmes. By observing an individual's approach and contribution within a team, patterns of design behaviour are highlighted and compared within the industrial and academic examples. Initial findings have identified discreet differences in design approach and ways of working. By identifying these initial character clusters, design behaviour can be predicted to help teams and individuals to strengthen their design process. This research brings together: 1. The design process and how engineering and design teams work to solve problems. 2. The natural characteristics of individuals and how they approach problems. This difference of approach can be viewed in relation to the design process where engineers and designers will recognise their preference for certain stages of the design process. This study suggests that these individual preferences are suited to different stages of the design process, and that industry uses teams to ensure a broad range of views, an approach design education would do well to apply by establishing collaborative input in the design process.
Resumo:
While cross-cultural consumer behaviour and its impact on marketing strategies has received considerable interest within the marketing literature, differences between ethnic groups within countries have received significantly less attention. This study examines the effect of within-country ethnic differences on brand positioning, using the UK automobile industry as a context. Both qualitative and quantitative research is used to identify the perceptions of two sub-cultural groups: British of Indian extraction, and Caucasian British. It was found that these two groups display appreciably different values, and also place different levels of importance on different product attributes when evaluating brands. Furthermore, the two groups exhibited different perceptions of the same set of brands. The results suggest that, to position brands effectively, marketers should take account of cultural diversity within countries as well as between them.
Resumo:
With the competitive challenge facing business today, the need to keep cost down and quality up is a matter of survival. One way in which wire manufacturers can meet this challenge is to possess a thorough understanding of deformation, friction and lubrication during the wire drawing process, and therefore to make good decisions regarding the selection and application of lubricants as well as the die design. Friction, lubrication and die design during wire drawing thus become the subject of this study. Although theoretical and experimental investigations have been being carried out ever since the establishment of wire drawing technology, many problems remain unsolved. It is therefore necessary to conduct further research on traditional and fundamental subjects such as the mechanics of deformation, friction, lubrication and die design in wire drawing. Drawing experiments were carried out on an existing bull-block under different cross-sectional area reductions, different speeds and different lubricants. The instrumentation to measure drawing load and drawing speed was set up and connected to the wire drawing machine, together with a data acquisition system. A die box connected to the existing die holder for using dry soap lubricant was designed and tested. The experimental results in terms of drawing stress vs percentage area reduction curves under different drawing conditions were analysed and compared. The effects on drawing stress of friction, lubrication, drawing speed and pressure die nozzle are discussed. In order to determine the flow stress of the material during deformation, tensile tests were performed on an Instron universal test machine, using the wires drawn under different area reductions. A polynomial function is used to correlate the flow stress of the material with the plastic strain, on which a general computer program has been written to find out the coefficients of the stress-strain function. The residual lubricant film on the steel wire after drawing was examined both radially and longitudinally using an SEM and optical microscope. The lubricant film on the drawn wire was clearly observed. Therefore, the micro-analysis by SEM provides a way of friction and lubrication assessment in wire drawing.
Resumo:
This paper provides an updated review on fast pyrolysis of biomass for production of a liquid usually referred to as bio-oil. The technology of fast pyrolysis is described including the major reaction systems. The primary liquid product is characterised by reference to the many properties that impact on its use. These properties have caused increasingly extensive research to be undertaken to address properties that need modification and this area is reviewed in terms of physical, catalytic and chemical upgrading. Of particular note is the increasing diversity of methods and catalysts and particularly the complexity and sophistication of multi-functional catalyst systems. It is also important to see more companies involved in this technology area and increased take-up of evolving upgrading processes. © 2011 Elsevier Ltd.
Resumo:
The multiterminal dc wind farm is a promising topology with a voltage-source inverter (VSI) connection at the onshore grid. Voltage-source converters (VSCs) are robust to ac-side fault conditions. However, they are vulnerable to dc faults on the dc side of the converter. This paper analyzes dc faults, their transients, and the resulting protection issues. Overcurrent faults are analyzed in detail and provide an insight into protection system design. The radial wind farm topology with star or string connection is considered. The outcomes may be applicable for VSCs in the multi-VSC dc wind farm collection grid and VSC-based high-voltage direct current (HVDC) offshore transmission systems.