Wirkungsgradsteigerungen moderner Turbomaschinen machen dort auch zukünftig verstellbare Leitschaufeln unverzichtbar. Infolge komplexer Ringraumgeometrie entstehen bei der Schaufelverstellung betriebspunktabhängige Radialspalte, welche hinsichtlich Effizienzoptimierungen eine zunehmende Rolle spielen. Die vorliegende Arbeit charakterisiert die aerodynamischen Mechanismen und das Potential von spezifischen radialen Teilspalt- und Seitenwandkonturgeometrien solcher Verstellstatoren. Anders als bei durchgehenden radialen Spalten variiert der Einfluss der Teilspalte abhängig von deren axialer Position. Ein Teilspalt im hinteren Schaufelsehnenbereich erreicht reduzierte Totaldruckverluste gegenüber einer spaltfreien Referenz- beschaufelung. Dieser Vorteil vergrößert sich mit steigender Gitterbelastung und erhöht sich nochmals im Vergleich mit Konfigurationen eines vorderen Teilspaltes. Die Ergebnisse zei- gen, dass die Position entlang der Sehne der wesentliche Ein- flussfaktor auf die Radialspaltcharakteristik ist, die Spaltlänge als auch deren radiale Variation spielen nur eine untergeordnete, quantitative Rolle. Auch die untersuchten modellhaften Seitenwandkonturen wirken sich aufgrund sekundärer geome- trischer Einflüsse positiv auf Verlust und Gitterumlenkung in der Abströmung aus. Reduzierte Abmessungen der Teilspalte schwächen auch charakteristische Periodizitäten in Verbindung mit Spaltströmung bzw. resultierendem Spaltwirbel ab. Diese Erkenntnisse erlauben aerodynamische Optimierungen der Geometrie eines spezifischen Statordesigns. Ebenso ergibt sich ein Anwendungspotential im Randbereich starrer Leitschaufeln.

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För att industrier ska hålla sig tekniskt uppdaterade krävs det att studenter, som så småningom blir personal, får utbildning som strävar efter modernisering. En viktig del inom modernisering i dag är automatisering via exempelvis automatiserad additiv tillverkning och off-line-programmering (OLP) som båda besitter stor potential, inte minst inom tillverkningsindustrin. Dessvärre så förekommer det brist på dokumentation om hur denna process går till steg för steg till färdig produkt, därför ämnar sig denna studie till att försöka täcka denna kunskapslucka genom att tillhandahålla en nybörjarvänlig dokumentation om processerna. Dokumentationen ska kunna bidra som referensverktyg i utbildningssyfte, där användaren kan genom nybörjarvänliga guider följa processen steg-för-steg från CAD-modell i SolidWorks till skapandet av robotbanor via 3D-printerprogrammet Slic3r och genom simuleringsprogrammen RoboDK och MotoSim utföra OLP som leder till simulering av additiv tillverkning. Tillvägagångssättet som tagits fram i denna studie valideras även genom automatiserad additiv tillverkning i verklig robotcell. Olika problem och idéer kring framtida forskning tas även upp i denna studie för att kunna utveckla och optimera processen. / In order for industries to stay technically up-to-date, it is necessary that students, who eventually become staff, receive education that strives for modernization. An important part of modernization today is automation via, for example, automated additive manufacturing and off-line programming (OLP), both of which have great potential, not least in the manufacturing industry. Unfortunately, there is a lack of documentation on how this process goes step by step to the finished product, so this study aims to try to cover this knowledge gap by providing a beginner-friendly documentation on the processes. The documentation should be able to contribute as a reference tool for educational purposes, where the user can through beginner-friendly guides follow the process step-by-step from CAD model in SolidWorks to the creation of robot paths via the 3D printer program Slic3r and through the simulation programs RoboDK and MotoSim perform OLP leading to simulation of additive manufacturing. The approach developed in this study is also validated through automated additive manufacturing in real robot cells. Various problems and ideas about future research are also addressed in this study in order to be able to develop and optimize the process.

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Selon une étude récente, le Guide de recherche d’une orientation professionnelle (GROP-3; Roy & Roy, 2008) est l’outil le plus utilisé par les conseillers d’orientation dans un contexte d’exploration de choix de carrière (Le Corff, Yergeau, Savard, Lamarche & Gingras, 2011). Il s’agit d’un instrument de 277 items répondus sur une échelle en cinq points qui comprend trois sections mesurant les intérêts professionnels, les traits personnels et les valeurs. Des études ont permis de démontrer la validité du GROP-3 auprès d’étudiants (Gingras, 2013; Keck, 2015; Morin-Saint-Hilaire, 2010), mais il s’avère maintenant pertinent de s’intéresser aux qualités métriques de la nouvelle édition du GROP (GROP-4; Roy & Roy, 2018), et ce, auprès de groupes de travailleurs. Pour ce faire, 477 participants recrutés auprès de différents regroupements de travailleurs préalablement identifiés pour représenter chacun des thèmes de la typologie de Holland (Holland, 1966, 1973, 1985) ont rempli l’Orientation par soimême (OPSM; Holland, 1994), le Mini International Personality Item Pool (Mini-IPIP; Donnellan, Oswald, Baird, & Lucas, 2006) et le GROP-4. Les corrélations entre le GROP-4 et les autres mesures s’avèrent conformes aux hypothèses émises et constituent de bons indices des validités convergente et divergente de l’instrument. De plus, les personnes occupant un emploi nécessitant la réalisation d’activités types de la théorie de Holland montrent des scores d’intérêts plus élevés à ce type d’activités au GROP. Le domaine d’occupation des travailleurs peut aussi être prédit en fonction des scores au GROP dans 77,5 % des cas. Somme toute, les résultats suggèrent que le GROP-4 est un outil d’évaluation des intérêts et de la personnalité valide et qu’il peut prédire le domaine d’occupation des travailleurs. Des études additionnelles sont toutefois nécessaires pour vérifier la validité de la section de l’instrument qui porte sur les valeurs et la pertinence de l’ajout du domaine d’intérêts Éveilleur à la typologie de Holland.

Modern gas turbine designs' ever-increasing turbine inlet temperature raises challenges for the nozzle guide vane cooling. Two typical endwall cooling schemes, jump cooling and louver cooling, result in different interactions between the injected coolant and the mainstream, leading to different cooling effects. This study investigates these two cooling schemes on the endwall cooling experimentally and numerically. Wind tunnel tests and the CFD simulations are carried out with engine-representative conditions of an exit Mach number of 0.85, an exit Reynolds number of 1.5×10^6, and an inlet Turbulence intensity of 16%. The jump cooling scheme experiments investigate two blowing ratios, 2.5 and 3.5, two density ratios, 1.2 and 1.95, and three endwall profiles with different NGV-turbine alignments. Four coolant mass flow ratios from 1.0% to 4.0% are tested for the louver cooling. The results show that the cavity vortex, the horseshoe vortex, and the passage vortex are the main factors that prevent the upstream coolant from reaching the NGV passage. The jump cooling scheme generally provides high momentum to the cooling jets. As a result, the coolant at the design case density ratio of 1.95 and blowing ratio of 2.5 is sufficiently energized to penetrate the horseshoe vortex. It then forms a relatively uniform coolant film near the NGV passage inlet, leading to a minimum adiabatic cooling effectiveness of 0.4 throughout the passage. Reducing the coolant density or increasing the blowing ratio leads to higher coolant momentum, so the coolant jets can further suppress the horseshoe vortex. However, high momentum may cause coolant lift-off, mitigating the coolant reattachment. Therefore, the density ratio needs to be carefully balanced with the blowing ratio to optimize the cooling effect. This balance is also affected by the combustor-NGV misalignment, as a higher step height requires higher coolant momentum to overcome the step-induced vortices. On the contrary, the louver cooling scheme provides less momentum to the coolant. The results showed that only by exceeding a coolant mass flow rate of 1~2% can the coolant form a uniform film which provides good coverage upstream of the NGV passage inlet. As for the cooling of the NGV passage, the mass flow rate ratio of the range investigated is not sufficient for desirable cooling performance. The pressure side endwall proves most difficult for the coolant to reach. In addition, the fishmouth cavity at the combustor-NGV passage causes a three-dimensional cavity vortex that transports the coolant in the pitch-wise direction. Moreover, the coolant transport pattern is dependent on the coolant blow rate. Overall, the more-energized coolant film generated by the jump cooling tends to survive longer, but it is also more prone to lift-off. At the same time, the less-energized coolant film caused by the louver cooling is more susceptible to vortices and the discontinuity of the endwall geometry. However, it develops faster, especially in the lateral direction. The two schemes could be applied simultaneously for an ideal cooling system. The jump cooling can provide enough momentum for the coolant to persist in the NGV passage. Meanwhile, the louver cooling covers the upstream region before the jump cooling coolant reattaches to the endwall. / Doctor of Philosophy / Gas turbines, sometimes called combustion turbines, are widely used to generate power or propulsion for various applications. The three main components of a gas turbine are compressor, combustor, and turbine. Modern gas turbines run at a high turbine inlet temperature that exceeds the current metal limits to increase efficiency. However, this brings significant challenges to the cooling of the first stage of the turbine, the nozzle guide vane. In this research, two commonly used endwall cooling methods, jump cooling and louver cooling, are investigated under engine-representative conditions experimentally and numerically. In addition, flow physics is demonstrated to explain the endwall cooling performance, mainly the upstream boundary layer caused by the interaction between the mainstream and the coolant flow. The results show that the cavity vortex, the horseshoe vortex, and the passage vortex are the main factors that prevent the upstream coolant from reaching the NGV passage. The jump cooling scheme provides high momentum to the cooling jets. As a result, the coolant in the design case is sufficiently energized to penetrate the horseshoe vortex, providing a desirable cooling effect in the NGV passage. Reducing the density ratio or increasing the blowing ratio can help the coolant jets further suppress the horseshoe vortex but also causes more lift-off, which adversely affects the cooling performance. On the contrary, the louver cooling scheme provides less momentum to the coolant, forming a less energized coolant film. The lack of coolant causes the louver coolant film to provide good coverage immediately downstream of the louver scheme exit. However, due to unfavorable interaction with vortices and endwall discontinuity, the cooling effect decays quickly downstream. Overall, the more-energized coolant film generated by the jump cooling tends to survive longer, but it is also more prone to lift-off. At the same time, the less-energized coolant film caused by the louver cooling is more susceptible to vortices and the discontinuity of the endwall geometry. However, it develops faster, especially in the lateral direction. The two schemes could be applied simultaneously for an ideal cooling system to work mutually beneficially.