Aerodynamics and modelling of vane-swirled flames in furnaces

Swirl produces notable effects on flames, generally making them shorter and highly stable over a wide range of air and fuel flows. One common method of generating a swirling jet is to employ a vane swirler. In this work the aerodynamics of vane-swirled premixed town gas-air flames are investigated in two furnaces, using the same swirlers. Variables investigated include the swirler vane angle, geometry, degree of confinement, Reynolds Number and fuel/air ratio. Cold tests were also carried out for the purpose of modelling. Significant changes in the flow and the combustion patterns were produced by swirl. Strong swirl created a central recirculation zone which when well established had a maximum diameter and length of nearly fixed proportions of the furnace diameter. The jet spread rate was found to increase mainly with the swirler-vane angle and to vary slightly with combustion and confinement particularly at strong swirl. The presence of a central hub in the swirler had little effect on the flow and combustion pattern. The survey of previous work and the present results showed the need for a revised measure of swirl, This was taken as the ratio of the tangential to axial velocity momentum fluxes divided by the furnace diameter. The values of this Swirl Number obtained by integrations of the flow properties were found to be a valuable index of the flow and combustion patterns. A critical value at which the flow reversal occurs was found to be the same for all input conditions tested. The strong relation between combustion and flow patterns shows the value of isothermal model results for furnace design. For a non-swirled flame a parameter was derived on the basis of the ratio of source to shear momenta. For swirling flames, the use of the Swirl Number defined above proved to be a satisfactory modelling criterion since it has a fixed relation to the flow pattern under both cold and burning conditions. A mathematical model was developed for the prediction of the flow and combustion patterns of confined swirling flows. The results obtained for weak and medium degrees of swirl were reasonably similar to those experimentally measured. The study of the measured combustion patterns shows that swirling flames are stabilized by a mechanism of mixing between the fresh charge and the recirculated gases. These contained direct combustion products and entrained gases from the surroundings. The effective fuel/air ratio at the reaction zone versus blow-off velocity relations were obtained and found to be the same for both free and confined swirling flames. Finally some recommendations to the choice of the optimum swirl range and suggestions for further work are presented. A paper presented at the Combustion Institute European Symposium (1973) is included as an Appendix

Hygge, Hope and Higher Education: A Case Study of Denmark

Higher education institutions have been profoundly reshaped by processes associated with neoliberalism. In this chapter, Larsen outlines the ways in which Denmark has ushered in marketdriven reforms to the Danish higher education system to enhance their institutional competitiveness over the past 30 years. Research on the impacts of neoliberal higher education reforms on faculty is reviewed and the author discusses her experiences (at a Canadian university) with market-driven, accountability reforms. The chapter shifts direction and provides the reader with an overview of the concept of hygge, an idealized Danish term that has connotations of coziness, safety, friendliness, and intimacy. Larsen recounts her experiences as a Canadian academic on sabbatical at a Danish university in 2017, illustrating the ways in which she experienced hygge in the Danish university setting. In the final section of the chapter, Larsen argues that hygge can be viewed as a retreat from the individualism, competition, market stratification and other challenges associated with neoliberalism. Hygge marks out the boundaries between the cold and heartless market-place and the warm and cozy home, and despite critiques that is instantiates exclusions, hygge offers hope to resist the alienation associated with neoliberalism and provide an alternative ethos for close and safe social relations within academia

Exaptation in a digital innovation ecosystem: the disruptive impacts of 3D printing

This research investigates disruptive innovation through the under-explored relationship between two ecological concepts, exaptation and ecosystems. Exaptation-driven innovation involves exploiting unintended latent functions of pre-existing technologies. Digital innovation ecosystems account for industry-spanning co-operative and competitive dynamics among firms related to innovations that combine physical and digital elements, such as 3D printing. In this work the evolution of the 3D printing ecosystem is traced over four decades, from the first patents—presented as exaptation-driven innovations—to the present threat of disruption to established manufacturing. Through a longitudinal narrative study of the formation and growth of this ecosystem, a four-phase process model is developed. This addresses gaps in the exaptation and disruptive innovation literatures with respect to innovation ecosystems. The implications for theory are that disruption requires an appropriate supporting ecosystem, but ecosystems take on a life of their own, so cultivating a healthy ecosystem means sowing the seeds of disruption within that ecosystem. For practice, this research highlights the managerial challenges of predicting disruption by exaptation-driven innovations and the constant competition for niches within ecosystems. For policy, it outlines implications concerning how best to support new innovation ecosystems and cultivate exaptation opportunities

Harnessing exaptation and ecosystem strategy for accelerated innovation: lessons from the VentilatorChallengeUK

The COVID-19 crisis has underlined the need for accelerated innovation to rapidly help business solve social problems. These problems require access to capabilities and knowledge that no single organization or existing supply chain possesses. Drawing on the experience of the open innovation and rapid-scale-up achieved by the VentilatorChallengeUK to address a shortage of ventilators required by patients seriously ill with COVID-19, this article develops a framework for accelerated innovation and delivery that crosses traditional industry boundaries. It offers a series of important lessons for how open innovation, exaptation, and ecosystem strategies—backed by a set of enabling initiatives—can be used to solve multi-faceted social and business problems at speed

Design scoreboard: capturing design spending in firms

The value of design is increasingly recognised, but design is often overlooked in favour of R&D in the measurement of innovation. Design is difficult to define, which makes it difficult to measure in financial terms. R&D was previously considered difficult to measure, but, as it is now well defined, financial measures of R&D have been established. Several previous studies demonstrated the commercial value of design, but failed to propose a reliable approach to capture design spending at the level of the firm. This paper presents a framework for classifying design activities and capturing design spending in firms. A number of exploratory case studies were conducted, four of which are described, to explore how companies understood design and how it could be measured. A conceptual model, by which the extent of design activity in firms may be better understood, is proposed. This model will be used as the basis of questions in a survey of design spending in UK firms

Towards a national design scoreboard: a model to enable comparison of performance between countries

Abstract--Recognising the growing importance of design at a national level, this paper reports on the development of a suite of measures relating to national design performance. These measures are based around a simplified model of design as a system at a national level, developed through a workshop with government, industry and design sector representatives. Detailed data on design in the UK is presented to highlight the difficulties in collecting reliable and robust data. Evidence is compared with four countries (Spain, Canada, South Korea and Sweden). This comparison highlights the inherent difficulties in comparing performance and a revised set of measures is proposed