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Roads are a key element of infrastructure connecting people, goods, and services. Increasing the sustainability of road construction helps balance the ecological impact of economic growth. Some road materials like hot mix asphalt (HMA) can be recycled and reused in new road construction. Increasing the amount of reclaimed asphalt product (RAP) in new road construction reduces waste and cost in raw materials but requires additional energy to reheat the RAP. Therefore, improving the thermal efficiency of HMA production is a necessary step for increasing RAP usage. Simulation offers a tool to improve the thermal efficiency of mixing equipment, but only if the numerical models can capture the relevant physics at the industrial scale. While conductive heat transfer is the dominant mode in some methods of aggregate and RAP heating because these materials have low thermal conductivity, much of the heat transfer will occur through interstitial gases. Multi-phase methods are often computationally expensive, placing many industrial scale applications beyond reach. The objective of this study is to create a tool to make the simulation of heat transfer in dense granular systems where the gas contribution is important tractable at the industrial scale. To that end, a simple particle-based model is proposed that includes the contribution of the interstitial gases to conduction in dense granular materials. The model was developed using a multi-scale approach to correlate the effect of interstitial gases on conduction heat transfer in randomly packed samples to the local packing structure. The model was then validated against an experiment of a static, heat column of glass beads and found to better approximate the temperature distribution than a more complex and computationally expensive method. The model was then tested in a dense, dynamic system by comparing the results to experimental data for glass beads in an indirectly heated rotating drum. The model was shown to capture the bulk average temperature rise in the glass beads. Further virtual tests were performed to validate the model against an experiment of mixing hot and cold aggregate particles in a flighted, inclined drum. Results from the simulation show a good agreement with the experiment for the temperature rise in the cold particles demonstrating the model's ability to capture the gas contribution in dynamic systems of irregular shaped particles. Finally, the model was used to improve heat exchange to recycled asphalt in a full-scale mixer, demonstrating the model's value to improve equipment design.

This thesis demonstrates that the most popular periodical genre of the second half of the nineteenth century was the provincial newspaper. Using evidence from news rooms, libraries, the trade press and oral history, it argues that the majority of readers (particularly working-class readers) preferred the local press, because of its faster delivery of news, and because of its local and localised content. Building on the work of Law and Potter, the thesis treats the provincial press as a national network and a national system, a structure which enabled it to offer a more effective news distribution service than metropolitan papers. Taking the town of Preston, Lancashire, as a case study, this thesis provides some background to the most popular local publications of the period, and uses the diaries of Preston journalist Anthony Hewitson as a case study of the career of a local reporter, editor and proprietor. Three examples of how the local press consciously promoted local identity are discussed: Hewitson’s remoulding of the Preston Chronicle, the same paper’s changing treatment of Lancashire dialect, and coverage of professional football. These case studies demonstrate some of the local press content that could not practically be provided by metropolitan publications. The ‘reading world’ of this provincial town is reconstructed, to reveal the historical circumstances in which newspapers and the local paper in particular were read. Evidence from readers demonstrates the many ways in which they used the local press, both collectively and individually, including its use in sustaining local identities and sense of place. However, the local press was only one factor among many in the development and sustenance of local identities. The originality of the thesis lies in its introduction of empirical reading evidence into English newspaper history, its challenge to the taken-for-granted but problematic concepts of ‘local’ and ‘national’ newspapers in this period, its detailed study of the journalistic techniques used to capitalise on local patriotism, and its critique of many theories of nineteenth-century press history which have been based on a minority of the period’s newspapers, those published in London.