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Diplomová práce se zabývá prouděním v hydrocyklónu. Hydrocyklón je separační stroj, kterým slouží k oddělování pevných částice z kapaliny (nejčastěji z vody). Díky tangenciálnímu vstupu do zařízení nastává silné vířivé proudění, které způsobuje přisávání vzduchu přes horní a dolní výtok. Toto vzduchové jádro hraje důležitou roli v separaci částic. Výpočty jsou provedeny pomoci CFD.

L'exploitation minière des sables bitumineux requiert une succession de nombreuses opérations pour séparer le bitume, l'eau et le sable. La séparation solide/liquide fait intervenir un hydrocyclone. Afin de limiter l'ajout d'eau, l'hydrocyclone doit fonctionner dans des conditions inhabituelles correspondant à une concentration élevée à l'alimentation. Une étude expérimentale a permis de caractériser l'ensemble des régimes de fonctionnement, l'influence de la concentration et des caractéristiques géométriques. De plus, des simulations numériques ont été réalisées avec NEPTUNE_CFD@Tlse. Deux méthodes sont proposées pour modéliser les comportements observés à faible et à forte concentration. Les résultats numériques sont en bon accord avec les expériences sur toute la gamme de concentration. L'étude des phénomènes locaux permet une meilleure compréhension des mécanismes de séparation. / Tar sands beneficiation requires a series of processing steps for separation of bitumen, water and sand particles. In this process, hydrocyclones are used to separate sand from water and bitumen, thereby recovering additional bitumen and concentrating sand particles before sending them off to tailing ponds. In order to reduce fresh water consumption (environmental policy), hydrocyclones need to operate with high feed solids content, say 50% in mass, which lays outside their standard operating regime. The response and performance of hydrocyclones need to be understood under such stringent operating conditions. A pilot scale experiment was commissioned for testing a 100mm diam. hydrocyclone under different operating regimes of discharge and measuring the corresponding separation performance. Feed solids concentration and geometrical properties were varied extensively. Separation performance indicators, including partition curve, cut-size, sharpness index and water recovery to underflow were obtained by standard data reconciliation. The experimental data provided all the information required to test the CFD model that was derived to simulate the hydrocyclone. Eulerian simulations of the three-dimensional liquid-solid flow inside the hydrocyclone were carried out, using a multi-fluid model (NEPTUNE_ CFD@Tlse). The actual geometrical features and operating conditions of the hydrocyclone were accurately matched in the simulations. Two simulation approaches have been proposed for hydrocyclone modelling, depending on their operating under dilute conditions, with a spray discharge or dense conditions, with a rope discharge. Numerical simulation results are in good agreement with experiments. Local analysis of hydrodynamic features yields new insights into the behaviour of hydrocyclones at high feed solids concentration.

京都大学 / 新制・課程博士 / 博士(工学) / 甲第23201号 / 工博第4845号 / 新制||工||1757(附属図書館) / 京都大学大学院工学研究科電気工学専攻 / (主査)教授 引原 隆士, 教授 松尾 哲司, 特定教授 中村 武恒 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

The research presented in this doctoral dissertation introduces a developmental path to realize micro coaxial transmission lines for wafer-level microwave and millimeter wave circuits. The micro coax lines conceptualized in this research are three-dimensional, with a uniquely low vertical profile of 20 mu m. They are distinguishable from other transmission line topologies due to frequency limitless, cross-talk free performance in high density circuits resulting from the totally shielded construction. Design and optimization was done using equations and electromagnetic simulations. Extensive process development has been carried out to fabricate these devices on CMOS grade silicon wafers using processes amenable to the IC manufacturing industry. Micro coax lines of three different core types including air, semi-dielectric and all-dielectric cores were designed, fabricated and analyzed from 1 - 40 GHz with respect to line impedance and the volume of polyimide (dielectric) in the micro coax cavity. The insertion loss of the lines was found to vary from 2 to 9 dB/cm depending on the width the center conductor, total cross-sectional area and core type. The versatility of the micro coax technology developed in the earlier part of this research has been successfully integrated with RF MEMS to embed a MEM varactor inside the micro coax cavity capable of achieving a capacitance ratio around 7 with an actuation voltage of 40 - 60V. The vertical integration capability of the micro coax was demonstrated by locating a millimeter wave slot antenna on the top side shield of a rectangular micro coax line, also acting as the electromagnetically coupled feed for the antenna. The antenna was designed to operate in the full range of the unlicensed 57 - 64 GHz spectrum capable of Gbps data rates. A 15 dB bandwidth of 17% and a hemispherical radiation pattern was achieved. Lastly, a diversified application involving the application of an integrated micro coax probe-microfluidic chamber approach to detect bacteria through impedance measurements has been introduced. In summary, the development and implementation of micro coax technology on a large scale is bound to create a paradigm shift in the development of high density microwave and millimeter wave circuits for RF MEMS and integrated antennas.

Current source is used in auxiliary power supplies, battery chargers, and LED drivers. The battery chargers are required to provide constant current within a wide output voltage range, similar to LED drivers. The load-independent (LI) Class-E inverter is a promising topology for such applications since it can realize zero-voltage switching (ZVS) within a wide load range. Class-E current source can be achieved by converting constant voltage (CV) Class-E inverter to current source with a trans-susceptance network or using parallel resonant topology. The design and analysis of LI Class-E inverters usually assume a high-Q resonant load tank so that the load current/voltage is sinusoidal. While this is the case in RF applications, it's not required in DC-DC power conversion. Besides, high-Q design leads to high inductance and increased voltage/current stress on the resonant components, increasing converter volume, loss, and cost. This work aims to provide a design guideline for the CC Class-E inverter when significant harmonics are present by reflecting the trade-off between load range and voltage stress, with the help of a modified frequency domain analysis method to eliminate the iteration existing in the time domain analysis. Output current variation and voltage stress can be automatically quantified when circuit parameters vary. Generalized load range contours are obtained to guide the circuit design. With the help of the analysis, a 10-W dual-output Class-E gate power supply is designed with optimized magnetics and reduced isolation capacitance. Compared with CC Class-E based on trans-susceptance network, the parallel resonant CC Class-E inverter has smaller part counts due to its low-order resonant network. However, the current topology suffers from limited maximum output power. In this work, a coupled-inductor based parallel resonant CC Class-E inverter is proposed with more than 2 times maximum power without increasing part counts. / Doctor of Philosophy / Current source is used in auxiliary power supplies, battery chargers, and LED drivers. The battery chargers are required to provide constant current within a wide output voltage range, similar to LED drivers. The load-independent (LI) Class-E inverter is a promising topology for such applications since it can realize zero-voltage switching (ZVS) within a wide load range. This work aims to provide a new design guideline for the CC Class-E inverter when significant harmonics are present by reflecting the trade-off between load range and voltage stress, with the help of a modified frequency domain analysis method to eliminate the iteration existing in the time domain analysis. Output current variation and voltage stress can be automatically quantified when circuit parameters vary. Generalized load range contours are obtained to guide the circuit design. With the help of the analysis, a 10-W dual-output Class-E gate power supply is designed with optimized magnetics and reduced isolation capacitance. Compared with CC Class-E based on trans-susceptance network, the parallel resonant CC Class-E inverter has smaller part counts due to its low-order resonant network. However, the current topology suffers from limited maximum output power. In this work, a coupled-inductor based parallel resonant CC Class-E inverter is proposed with more than 2 times maximum power without increasing part counts.

This thesis focuses on inductive base sensor design at MHz range frequency. The background theory, design, experiments and results for a new magnetic particles sensor is presented. A new magnetic sensor based on a planar coil was investigated for DNA pathogen detection. Change in inductance of the planar coil due to the presence of magnetic particles with varying mass was measured. The experimental set-up consisted of different sized planar coil with associated electronics for inductance measurements. The best sensor performance was accomplished using two different inductors while oscillating at frequencies 2.4MHz using 9.5μH inductor and 7.2MHz with 85μH inductor. The sensor has very large signal to noise ratio (580×103), while the average amount of frequency drift was 0.58. This sensor was tested with various types of magnetic particles. In addition, iron-oxide nanoparticles were synthesized through water in oil microemulsion method and with an average size of 25nm. The best sensitivity achieved for detection of 50μg iron-oxide particles was with the bead size of 10nm. 81Hz frequency shift was attained in regard to that amount of particles. This research shows that increasing the resonance frequency to 7.2MHz can cause the larger output signal difference (frequency shift) in the presence of magnetic particles; however, the sensor stability is the most important factor for determining the detection resolution and sensitivity. The sensitivity is better if the sensor can detect smaller amount of magnetic sample. The results of this research demonstrate that while the sample consists of smaller size particles, the sensor can detect the lower amount of sample. This is due to the heating effect of nanoparticles. On the other hand the sample distance from the sensor has a major impact on the sensitivity too; the shorter the distance, the higher the sensitivity. This technique can potentially be extended to detect several different types of bacterial pathogens and can be modified for multiplex quantitative detection. This sensing technique will be incorporated into a handheld, disposable microfluidic chip for point-of-care diagnostics for sexually transmitted diseases.

Detta examensarbete har utförts på uppdrag av Koenigsegg Automotive AB, som utvecklar, tillverkar och säljer högpresterande sportbilar. Företaget erbjuder fälgar tillverkade helt i kolfiberkomposit, som ger betydande viktbesparingar i jämförelse med traditionella metallfälgar. Efter tillverkningen kräver fälgarna viss bearbetning vid anläggningsytan mellan fälg och däck. Syftet med examensarbetet har varit att undersöka möjligheten att utföra bearbetningen av fälgarna in-house i Ängelholm, och målet har varit att konstruera en maskin för detta ändamål. Projektet inleddes med en litteratursökning, där svårigheter och möjligheter gällande bearbetning av kolfiberkompositer undersöktes. Till följd av de undersökningar som gjordes, valdes bearbetningsmetoden svarvfräsning och ett antal konstuktionskoncept genererades. Genom ett antal utvärderingar utvecklades ett speciellt koncept vidare till ett komplett produktförslag. Produktförslaget är komplett med analyser, beräkningar samt tillverkningsunderlag, som ger uppdragsgivaren bättre insikt i sina möjligheter. Även underlag som tillåter en framtida CE-märkning har tagits fram. Projektet har följt Fredy Olssons konstruktionsmetod. / The following thesis has been performed in cooperation with Koenigsegg Automotive AB, which develops, manufactures and sells high-performance sportscars. Koenigsegg offers rims made completely from carbon fiber composite, which yields substantial benefits in stiffness and weight compared to their traditional metal counterparts. After the manufacturing of the rims, some trimming is necessary in the contact surface between rim and tire. The purpose of this thesis has been to examine the possibility of performing the necessary trimming in-house in Ängelholm, by designing a special tool. The project began with a literature study, where possibilities and difficulties of machining carbon fiber composites were examined. As a result of the study, the manufacturing process turn-milling was chosen, and a number of concepts were generated. Through a series of evaluations, one concept was further developed to a final product. The suggested product is complete with calculations, analyses and drawings, which gives Koenigsegg a better insight of future possibilities. A solid foundation for future CE-marking has also been produced. The project has followed Fredy Olssons methods of Engineering Design.

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Thesis (MScEng)-- Stellenbosch University, 2013. / ENGLISH ABSTRACT: The objective of this project is to develop an electromagnetic model that can be used to accurately calculate the voltage distribution in a transformer winding structure when excited with standard impulse excitation waves. This voltage distribution is required during the design stage of a power transformer to ensure that the insulation is capable of withstanding the occurring electric field stresses during these tests. This study focuses on the modelling of a single disk-type power transformer winding without the presence of an iron-core. Methods of calculating self- and mutual-inductances of transformer windings are presented and validated by means of finite element method software simulations. The same is done for the calculation methods used for calculating the capacitances in and around the winding structure. The calculated and FEM-simulated results are compared to measured values as a final stage of validation. The methods used to calculate the various model parameters seem to produce results that agrees well with measured values. The non-linear frequency dependant dissipative nature of transformer windings is also investigated and a methodology to take this into account is proposed and implemented. The complete modelling methodology proposed in this thesis, which includes the calculation of the model parameters, model synthesis and solver algorithm, are applied to an actual case study. The case study is performed on an air-core reactor manufactured using a disk-type power transformer winding. The reactor is excited with standard lightning impulse waves and the voltages along the winding are measured. The calculated and measured voltage wave forms are compared in both the frequency and time-domain. From the comparison it is found that the model accurately represents the actual transient voltage response of the testunit for the frequency range of interest during standard factory acceptance tests. / AFRIKAANSE OPSOMMING: Die doel van hierdie projek is om 'n elektromagnetiese model te ontwikkel wat gebruik kan word om die spanningsverspreiding in 'n transformatorwindingstruktuur te bereken as standaard weerligimpulstoetse toegedien word. Hierdie spanningsverspreiding word vereis tydens die ontwerpstadium van ‘n kragtransformator om te verseker dat die isolasie in staat is om die elektriese veldsterkte tydens hierdie toetse te weerstaan. Hierdie studie fokus op die modelering van 'n enkele skyftipe-kragtransformatorwinding sonder die teenwoordigheid van 'n ysterkern. Metodes van berekening van self- n wedersydse-induktansie van transformatorwindings word aangebied en getoets deur middel van Eindige-Element-Metode (EEM) simulasies. Dieselfde word gedoen vir die metodes wat gebruik word vir die berekening van die kapasitansies in en rondom die windingstruktuur. Die berekende en EEM-gesimuleerde resultate word vergelyk met die gemeete waardes as 'n finale vlak van bekragtiging. Die metodes wat gebruik word om die verskillende modelparameters te bereken vergelyk goed met gemete waardes. Die nie-lineêre frekwensie-afhanklike verliese van transformatorwindings word ook ondersoek en 'n metode om hierdie in ag te neem is voorgestel en geïmplementeer. Die volledige voorgestelde modeleringsmetodiek in hierdie tesis, wat die berekening van die modelparameters, modelsintese en oplosingsalgoritme insluit word toegepas op 'n werklike gevallestudie. Die gevallestudie is uitgevoer op 'n lugkern-reaktor wat 'n skyftipe-kragtransformatorwinding. Die reaktor word onderwerp aan die standaard weerligimpuls golwe en die spanning al langs die winding word gemeet. Die berekende en gemete spanning golf vorms word met mekaar vergelyk in beide die frekwensie- en tyd-vlak. Uit die vergelyking blyk dit dat die model die werklike oorgangspanningsweergawe van die toetseenheid akkuraat verteenwoordig vir die frekwensie reeks van belang tydens standaard fabriekaanvaardingstoetse.