Flow control has always been an intense research subject with the pursuit of favourable control effects like drag reduction, transition delay, and separation prevention. In practice, these flow control effects are achieved using mechanical actuators such as deflectors, vortex generators, transverse jets and so on. However, such mechanical actuators may face the drag penalty and limitation of actuation response time. In recent years, energy deposition has been suggested as a novel flow control technique in high-speed flow with preferable characteristics like non-intrusive, easy arrangement and high actuation frequency. The motivation of this work is to experimentally explore the flow behaviour after the certain amount of energy is deposited in Mach 5 flow. The energy deposition is implemented using a thermal bump (surface energy deposition) and laser beam focusing (volumetric energy deposition).This work starts with the development of a measurement technique of luminescent paint for the present challenging hypersonic testing environment, which is used for the further energy deposition experiment. The successes of the luminescent paint development is demonstrated both on two-dimensional and axisymmetric models. The luminescent paint shows high spatial resolution and the accuracy comparing to the pressure transducer reading. The surface energy deposition is performed using an embedded heating element (thermal bump) on a flat plate. Qualitative and quantitative measurement techniques are utilised to study the modification to the flow structure and the alteration to the distribution of pressure and heat transfer rate after thermal bump is activated. The results reveal the appearance of induced shock wave and suspicious vortices traces due to the activated thermal bump as reported in other literatures. Re-distribution of surface pressure and heat transfer rate are also found.For the volumetric energy deposition, the laser beam is firstly focused in quiescent air in order to understand the induced flow pattern and the impingement to a solid plate. High-speed schlieren photography is utilised to provide an insight to the dynamic evolution of the induced shock wave propagation and plasma kernel development after laser-induced air breakdown. Then, the laser energy deposition is conducted over a flat plate with the presence of Mach 5 flow. The outward motion of the induced shock wave significantly distorts the boundary layer and changes the surface pressure distribution. The results show the different pattern of boundary distortion when laser beam energy is deposited at different positions downstream of the leading edge of flat plate. The entire induced flow pattern is similar to those induced by a pulsed micro-jet. In spite of the laser pulse width of 4 ns, the entire dynamic process lasts about 100 μs.

Ce travail a pour objectifs d’évaluer le potentiel d'une technique spécifique de caractérisation des propriétés d'écoulement des poudres : le rhéomètre à poudre FT4. L'objectif est de pouvoir mettre en place une analyse complète sur les avantages, les inconvénients et les limites d'utilisation des tests, l'impact de la cohésion des poudres et la répétabilité des mesures. Tout d'abord, des efforts sont faits pour explorer les différences entre la consolidation test de FT4 et le tap-tap. Les résultats indiquent que la consolidation test de FT4 a une bonne répétabilité, mais il peut sous-estimer la compressibilité des poudres. Cette méthode peut être optimisée en améliorant sa procédure d'initialisation pour donner des résultats cohérents en tant que le tap-tap. Deuxièmement, le cisaillement test de FT4 est comparé avec Schulze Ring Shear Tester et Evolution Powder Tester. Cette comparaison indique que le cisaillement test de FT4 peut sous-estimer la cohésion des poudres. Par conséquent, les dimensions des accessoires doivent être optimisées. Enfin, une nouvelle technique de caractérisation a été mise au point. Dans cette méthode, les poudres présentent des mouvements périodiques et la période correspondant peut être liée aux propriétés d'écoulement des poudres. Cette méthode a une très bonne capacité à identifier et à catégorier les propriétés d'écoulement de la poudre dans les conditions de faible contrainte. / This research has been dedicated to evaluate the reliability of the FT4 and to improve the current tests for a better and convenient powder characterization. Firstly, efforts are made to explore the differences between the compaction test provided by the FT4 and the traditional tapped density measurement. Results indicate that the FT4 compaction test has good repetability but it may underestimate powder compressibility. This method can be optimized by improving its initialization procedure to give consistent results as the tapped density measurement. Secondly, the shear tests provided by the FT4 are evaluated by comparing with the methodologies provided by Schulze Ring Shear Tester and Evolution Powder Tester. This comparison indicates that the FT4 shear cell test may underestimate powder strength, especially when a cohesive powder sample is measured, which may cause blockage when using the FT4 method to design a silo. To overcome this shortage, the dimensions of the shear accessories should be optimized. Most importantly, a new characterization technique has been developed. ln this method, powder materials present periodic motions and the cycle time of the periodic flow can be linked to the powder flow properties. This method has very good capability to identify and classify powder flow properties under low stress conditions.

Orchideoid mycorrhizal symbiosis (OM) can be found in nearly one tenth of higher plant species. This symbiosis is absolutely critical for orchids as they are unable to grow from seeds without external energy which is in nature provided by symbiotic fungi. The mechanism of transport between symbionts remains unknown. It is supposed that trehalose is one of the substances transported from fungi to plants as the source of energy. This thesis mainly aims to find out which other fungal saccharides could contribute to the process. The ability to utilize selected compounds was tested on protocorms of the common marsh orchid, Dactylorhiza majalis. The results showed that arabitol, erythritol, mannitol and sucralose are not utilized, while xylitol, sorbitol, glycerol and mannose are. Glutamin, an amino acid also suspected of participation in the OM transport, does not suffice as a source of energy. In orchids there were identified three groups of sequences coding for manitol dehydrogenase and two groups of sequences coding for sorbitol dehydrogenase. Key words: orchideoid mycorrhizal symbiosis, sugar alcohols, mannose, glutamine, carbon flow, energy flow, sorbitol dehydrogenase, in vitro

Im Beitrag wird zunächst die konventionelle auf Signalflüssen basierte Modellbildung mit modernen leistungsflussbasierten Methoden, die auf dem Prinzip von Aktion und Reaktion aufbauen, verglichen. BG (Bond Graph), POG (Power Oriented Graph) und EMR (Energetic Macroscopic representation) sind solche modernen Methoden die den Leistungsaustausch zwischen Teilsystemen als Grundlage für den Modellbildungsansatz nutzen. Diese Werkzeuge erhalten die physikalische Struktur, erlauben es in das dynamische System hineinzuschauen und unterstützen das Verständnis des Leistungsflusses. Unterschiede werden anhand verschiedener Eigenschaften in einer Tabelle angegeben. Nach Erläuterung der Grundlagen zu POG und BG erfolgt die Vorstellung einer Freeware Zusatzbibliothek zur Simulation von Bondgraphen. Spezielle Eigenschaften werden kurz umrissen. Diese Blockbibliothek läuft unter Simulink, besteht aus nur 9 mittels Menü konfigurierbaren Blöcken und realisiert bidirektionale Verbindungen. Die Beispiele Gleichstrommotor, Pulssteller und elastische Welle demonstrieren die Vorteile der leistungsflussorientierten Modellbildung. Zustandsregelung, Energieeffizienz und Simulink LTI Analysewerkzeuge führen in die Anwendung der vorgestellten Simulink Zusatzbibliothek für Bondgraphen ein.:Modellbildung dynamischer Systeme mittels Leistungsfluß 1. Leistungsfluß versus Signalfluß 2. Konjugierte Leistungsvariablen und Kausalität 3. Grundlagen Leistungsfluß orientierter Modellierung 3.1 Definitionen zum POG (Power Oriented Graph) 3.2 Definitionen zu Grundelementen für Bondgraphen (BG) 4. Freeware Bibliothek zur Simulation von Bondgraphen 4.1 Übersicht und Nutzerfreundlichkeit 4.2 Besonderheiten 5. Beispiele 5.1 Gleichstrommotor mit starrer Welle 5.2 Elastische Welle 5.3 Eingangsfilter und Pulssteller 5.4 Vereinfachter Antriebsstrang 6. Anwendung der Simulink Bondgraph Blockbibliothek 6.1 Beispiel elastische Welle 6.2 Zustandsregelung 6.3 Energieeffizienz 6.4 Simulink Analysewerkzeuge 7. Vorteile im Überblick / The paper starts with a comparison of the conventional modelling method based on signal flow and modern power flow oriented modelling methods based on the principle of action and reaction. BG (Bond Graph), POG (Power Oriented Graph) and EMR (Energetic Macroscopic representation) are such modern methods based on the power exchange between partial systems as a key element for the basic modelling approach. These tools preserve the physical structure, enable a view inside dynamical systems and support understanding the power flow. Relationships between these graphical representations will be given. After the explanation of basics for POG and BG an overview and special features of a freeware add-on library for simulation of BGs will be outlined. The block library runs under Simulink, consists of nine menu-driven customised blocks only and realises bidirectional connections. Examples DC motor, chopper and elastic shaft demonstrate the advantages of power flow oriented modelling. State space control, energy efficiency and Simulink LTI analysis tools exemplify the application of the presented Simulink add-on BG library.:Modellbildung dynamischer Systeme mittels Leistungsfluß 1. Leistungsfluß versus Signalfluß 2. Konjugierte Leistungsvariablen und Kausalität 3. Grundlagen Leistungsfluß orientierter Modellierung 3.1 Definitionen zum POG (Power Oriented Graph) 3.2 Definitionen zu Grundelementen für Bondgraphen (BG) 4. Freeware Bibliothek zur Simulation von Bondgraphen 4.1 Übersicht und Nutzerfreundlichkeit 4.2 Besonderheiten 5. Beispiele 5.1 Gleichstrommotor mit starrer Welle 5.2 Elastische Welle 5.3 Eingangsfilter und Pulssteller 5.4 Vereinfachter Antriebsstrang 6. Anwendung der Simulink Bondgraph Blockbibliothek 6.1 Beispiel elastische Welle 6.2 Zustandsregelung 6.3 Energieeffizienz 6.4 Simulink Analysewerkzeuge 7. Vorteile im Überblick