Multiple high-fidelity, time-accurate computational fluid dynamics simulations were performed to investigate the effects of upstream stator loading and rotor shock strength on vortex shedding characteristics in a single stage transonic compressor. Various configurations of a transonic axial compressor stage, including three stator/rotor axial spacings of close, mid, and far in conjunction with three stator loadings of decreased, nominal, and increased were simulated in order to understand the flow physics of transonic blade-row interactions. Low-speed compressors typically have reduced stator/rotor axial spacing in order to decrease engine weight, and also because there is an increase in efficiency with reduced axial spacing. The presence of a rotor bow shock in high-speed compressors causes additional losses as the shock interacts with the upstream stator trailing edge. This research analyzes the strength of shock-induced vortices due to these unsteady blade-row interactions. The time-accurate URANS code, TURBO, was used to generate periodic, quarter annulus simulations of the Blade Row Interaction compressor rig. Both time-averaged and time-accurate results compare well with experimentally-observed trends. It was observed that vortex shedding was synchronized to the passing of a rotor bow shock. Normal and large shock-induced vortices formed on the stator trailing edge immediately after the shock passing, but the large vortices were strengthened at the trailing edge due to a low-velocity region on the suction surface. This low velocity region was generated upstream of mid-chord on the suction surface from a shock-induced thickening of the boundary layer or separation bubble, due to the rotor bow shock reflecting off the stator trailing edge and propagating upstream. The circulation of the shock-induced vortices increased with shock strength (decreased axial spacing) and stator loading. Most design tools do not directly account for unsteady effects such as blade-row interactions, so a model is developed to help designers account for shock-induced vortex strength with varying shock strength and stator loading. An understanding of the unsteady interactions associated with blade loading and rotor shock strength in transonic stages will help compressor designers account for unsteady flow physics early in the design process.

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This research analyses how the medium of television has taken up the question of art history through the historical and critical review of series that have been acclaimed by their mass audiences. Viewed from a historical perspective, a number of milestone series have left their mark on the history of television and art. Some of them have contributed to the construction and dissemination of art-historical discourse, often formal and sometimes critical. This work examines film and television production on art in the developed countries of North America and Western Europe, notably the United States, France and the United Kingdom, at the time of the emergence and institutionalization of the medium of television, between 1945 and 1970, and then looks at the resonances in subsequent and contemporary programs. And, secondly, in a spirit of critical analysis, to try to understand what "television is doing to art and its history" in order to identify the specific discourse of television art history. In practical terms, the aim is to add to the literature on a subject that has so far received very little attention from art historians, and to help legitimize the medium as an object of art criticism. / Cette recherche analyse comment le média télévision s'est emparé de la question de l'histoire de l'art à travers l'examen historique et critique de séries plébiscitées par le grand public. Dans une perspective historique, un certain nombre de séries phares ont marqué l'histoire de la télévision et de l’art, dont certaines ont contribué à la construction et à la diffusion d'un discours sur l'histoire de l'art, souvent formel, parfois critique. Cet ouvrage examine d’une part, la production cinématographique et télévisuelle sur l'art dans les pays développés d'Amérique du Nord et d'Europe occidentale, notamment les États-Unis, la France et le Royaume-Uni, au moment de l'émergence et de l'institutionnalisation du média télévisuel, entre 1945 et 1970, puis leur résonance dans les programmes ultérieurs et contemporains. D'autre part, dans un esprit d'analyse critique, il s’agit de comprendre ce que "la télévision fait à l'art et à son histoire" afin d'identifier le discours spécifique de l'histoire de l'art télévisuelle. Concrètement, cette thèse vient enrichir la littérature sur un sujet jusqu'ici peu traité par les historiens de l'art et des médias, et contribuer à légitimer le média comme objet de la critique d'art.