Tlakové vířivé trysky (TVT) jsou používané v mnoha aplikacích, kde je potřebná velká plocha kapek nebo kde povrch musí být nanesen kapalinou, např. spalování, sprejové chlazení nebo nanášení barev. Parametry spreje z TVT jsou úzce spojené s jejich vnitřním prouděním. Obtokové trysky vylepšují koncepci klasických TVT přítomností otvoru, skrz který může kapalina odtékat zpět do nádrže. Díky této koncepci je možné regulovat vstřikovací množství kapaliny změnou průtoku tímto otvorem, zatímco se ve vířivé komůrce udržuje vysoký tlak, který zaručí dobrou kvalitu spreje. Obtokové trysky byly historicky málo prozkoumány a jejich vnitřní proudění nebylo studováno téměř vůbec. V této práci je popsáno vnitřní proudění několika obtokových trysek jak experimentálně, tak numericky. Tato data jsou následně korelována s měřenými vlastnostmi spreje. Výsledky ukazují, že přidání obtokového otvoru silně ovlivní vnitřní proudění i v případech, kdy obtokem neproudí žádná kapalina. V některých případech se vůbec nezformuje vzdušné jádro a tím se destabilizuje výtok z trysky, čímž vznikne nestabilní sprej. Mimoosé obtokové otvory generují a stabilizují vzdušné jádro, což pomáhá formovat kapalinovou stěnu a vysoce kvalitní sprej. Nicméně některé konfigurace změnily charakter rozpadu kapalinové stěny, což se projevilo i na kvalitě spreje. Navíc regulační schopnost a stabilita spreje závisí na vzdálenosti obtokových otvorů od osy vířivé komůrky. Na závěr byla upravena neviskózní teorie, která analyticky popisuje vnitřní proudění v TVT, tak aby byla aplikovatelná i na obtokové trysky. Pomocí tohoto přístupu byla odvozena teoretická predikce výtokového součinitele a velikosti vzdušného jádra v závislosti na obtokovém poměru (SFR). Zároveň byly pro obtokové trysky upraveny empirické korelace původně odvozené pro TVT. Tato práce přináší nový vhled k porozumění vnitřního proudění obtokových trysek a její výsledky najdou uplatnění při jejich návrhu.

Thesis dissertate power reactors and analyses techniques of an air-core power coils and inductors with ferromagnetic circuit and an air gap. Construction of the inductors verified the accuracy of the calculated values against the measured parameters. According to the outcome of this analysis, corrections of the design process are derived. Thesis design optimization to minimize size, weight, efficiency and in comparsion of these two factoctors.

<p>U ovoj doktorskoj tezi razvijen je postupak za ispitivanje uticaja<br />oklopa na merni transformator bez jezgra sa stanovišta<br />linearnosti transformatora i zaštite transformatora od<br />uticaja elektromagnetske smetnje. Formiran je parametarski model<br />oklopa i mernog transformatora bez jezgra. Izvedena su merenja<br />magnetskih karakteristika feromagnetskih materijala, dat je novi<br />analitički model histerezisa i određene su krive magnetisanja i<br />permeabilnosti materijala. Na osnovu numeričkih i<br />eksperimentalnih rezultata, a u skladu sa definisanim<br />kriterijumom, izvršena je analiza kvaliteta oklapanja za<br />razmatrane tipove oklopa.</p> / <p>In this thesis a method for examining the effects of shielding on a coreless<br />measuring transformer from the standpoint of transformer linearity and EM<br />radiation shielding is developed. A parametric model of the shield and the<br />coreless measuring transformer is constructed. Measurements of magnetic<br />properties of ferromagnetic materials were performed; a new analytical model<br />of hysteresis is developed; magnetization curves and permeability of the<br />materials are determined. Based on numerical and experimental results, and<br />using the defined criterion, the analysis of shielding quality of the considered<br />shield types was performed.</p>

No description available.

A new measurement of the neutron electric dipole moment (nEDM) is being developed at TRIUMF, where a high density source of ultra cold neutrons (UCN) is currently under construction. A fast, high-efficiency UCN detector is needed for the experiment, and a 6-Li doped glass scintillation detector is being explored for this purpose. In this work, simulations and test measurements were carried out to optimize the light guide design for the new UCN detector. Acrylic and air-core light guides, the latter with two different reflecting surfaces, were considered. Three prototype light guides were constructed and tested, and results were compared with simulations. The best solution was found to be an acrylic guide, wrapped with mylar foil. For a guide 12 cm in length as required by the experimental layout, a lower limit of approximately 25 photoelectrons per neutron capture was established for the proposed geometry and photomultiplier configuration. / May 2016

SHF Photoelektroneninjektoren sind eine vielversprechende Elektronquelle für hochbrillante Teichenbeschleuniger mit hohem mittlerem Strom und kurzen Teilchenpulsen, wie FELs und ERLs. Für das ERL Projekt bERLinPro wurde einer unabhängige Testanlage GunLab entwickelt um die Leistungsfähigkeit der Injektoren und die Strahlparameter zu überprüfen. Darüber hinaus können neue Komponenten zur Strahldiagnose getestet werden. Die Hauptaufgabe von GunLab ist die Beschreibung des vollständigen sechsdimensionalen Phasenraums der Elektronen in Abhängigkeit aller Injektorparameter. Die Anlage besteht aus einer kompakten Diagnosestrahlführungan dem SHF Photoelektroneninjektoren und einem Kathodenlasersystem. Im Rahmen dieser Arbeit wurden analytische und numerische Studien zu den SHF Photoelektroneninjektoren durchgeführt, um zu erwartende Strahlparameter zu detektieren und die Anforderungen an die Strahldiagnose festzulegen. Darüber hinaus wurden verschiedene Emittanzbeiträge der einzelnen Injektorkomponenten untersucht. Diesbezüglich wurde das Magnetfeld des aktuellen Solenoiden kartiert und auf Asymmetrien getestet, die ebenfalls zu Emittanzvergrößerungen beitragen können. Eine der wesentlichen Komponenten der Diagnosestrahlführung ist das (transversale) Phasenraummesssystem, für das eine besondere Magnetgeometrie entwickelt wurde. Weitere Diagnose Komponenten sind ein optimierter Spektrometerdipol und eine transversal ablenkende Kavität, durch die sich zusammen mit zwei Quadrupolmagneten die Scheibenemittanz bestimmen lässt. Für GunLab wurden unterschiedliche optische Messsysteme entwickelt und optimiert. Der herausforderndste Aufbau ist dabei das Strahl-Halo Messsystem. Es ermöglicht die Beobachtung der transversalen Ladungsverteilung über einen Dynamikbereich von bis zu 6 Größenordnungen. Die Leistungsfähigkeit und die Auflösung aller Messsysteme und Messroutinen wurden bestimmt, um die Visualisierung des kompletten Phasenraums durch GunLab sicher zu stellen. / SRF photoelectron injectors are promising electron sources for high brightness accelerators with high average current and short pulse duration like FELs and ERLs. For the ERL project bERLinPro an independent test facility called GunLab was developed and set up to optimize the operation performance of SRF photoinjectors and the electron beam parameters. Furthermore, GunLab allows to investigate the operation of different kinds of photocathodes in the environment of an SRF accelerator and to study new beam diagnostic concepts. Of outmost importance is the characterization of the full six dimensional phase space as a function of all injector parameters. GunLab consists of the compact diagnostic beam line, connected to the SRF photoinjetor module, and a drive laser. In the context of this thesis, analytical and numerical investigations of the SRF photoinjector were performed to estimate beam parameter ranges and to determine the diagnostics requirements. Furthermore, various emittance contributors of the injector were determined. Thereby the magnetic field of the final designed solenoid was measured to determine field asymmetries, which are one major source of emittance growth. One of the central diagnostic components of the beamline is the (horizontal) phase space scanner system. For this purpose, a dedicated air-coil magnet design was developed. Additional diagnostic components include an optimized spectrometer system, a transverse deflecting cavity (TCav) and two quadrupole magnets, to determine longitudinal and sliced emittance. For GunLab different optical measurement systems were developed and optimized, the most challenging setup is a beam halo measurement system. This device is able to observe the transverse charge density with a dynamic range of up to 6 orders of magnitude. The performance and the resolution of all measurement systems and routines for GunLab were determined to ensure the visualization of the electron beam phase space.

Moving parts cause vibrations and tend to wear out. In applications where maintenance is complicated, solutions without moving parts are therefore advantageous. Electrohydrodynamic pumps are such a solution. Instead of mechanical propulsion, they use strong electric fields to induce movement in a dielectric cooling liquid. These pumps require very little power, but to generate sufficiently strong electric fields, they need to be fed with very high voltage.  This project explored various methods for designing DC/DC-converters which fulfil the demands of an electrohydrodynamic pump. This was done by altering and combining existing topologies that were deemed to be relevant. The main method for testing and evaluation was by simulating in LTspice. The project also briefly investigated methods of overcurrent protection. This was relevant because gas bubbles in the cooling fluid can cause electric arcs which damage the pumps. Three converter topologies were chosen for further evaluation. First, a conventional resonant Royer-based converter that has previously been used by APR Technologies which was altered by the inclusion of a feedback loop. Second, a high-frequency resonant Royer-based converter with a planar air-core transformer. Third, a transformerless converter with a switched boost converter IC. All circuits included a Cockroft-Walton voltage multiplier bridge. The two resonant Royer-based converters fulfilled all requirements except the one on efficiency, while the transformerless converter fulfilled all requirements except the one on cost, set by APR. The more expensive transformerless converter had a significantly higher efficiency and a wider range of acceptable input voltages. Furthermore three general conclusions were drawn. The first was that planar air-core transformers are not beneficial compared to conventional transformers in these type of applications. The second was that a discrete voltage regulator controlled by feedback from the output is more effective than using a voltage regulator without feedback, as it also eliminates temperature and load variations. The third conclusion was that to protect the circuits from overcurrent, a large series resistor is needed, which causes significantly lowered efficiency.