Eating disorders are serious psychological disorders associated with debilitating lifestyle, multiple health problems and high rates of suicidality and mortality. Despite extensive research, the aetiology of eating disorders still remains unclear. Amongst the identified risk factors for eating disorders, stress has been frequently studied. The purpose of the present study was to explore the possibility that tail-pinch administered to rats could provide an animal model of stress-induced eating disturbances in humans, and whether environmental enrichment might ameliorate the effects of stress. In Experiment 1, we compared eating behaviours of rats that were reared in either enriched or standard environments and later exposed to tail-pinch and allowed to eat when food deprived. The study showed that a single exposure to tail-pinch induced eating disturbances in most of the rats. When rats were not food deprived, but were conditioned to eating when placed in test chamber, tail-pinch suppressed eating in all rats, but significantly more for rats reared under standard than in enriched conditions. Experiment 2 used a between-subjects design in which rats were reared in either a standard or enriched environment, and were either exposed to tail-pinch or not exposed during sessions in which they were not food deprived and allowed to eat. Tail-pinch suppressed the food intake of rats reared in enriched but not standard environments. Although this finding appeared to contradict results of Experiment 1, analysis of body weight revealed that exposure to tail pinch suppressed increases in weight gain across sessions more for rats reared in standard than enriched environments. The suppression of food intake during test sessions for enriched but not standard rats exposed to tail-pinch was attributed to differences in contextual conditioning and discrimination of the test chamber from home cages. Overall, results of the present study suggest that rats reared in enriched environments were more resilient to the effects of tail-pinch as a stressor. Implications of these findings for the understanding of human eating disorders are discussed.

Orientador: Roger Josef Zem / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-11T09:37:16Z (GMT). No. of bitstreams: 1 Pires_VictorFloresdaMatta_M.pdf: 1892182 bytes, checksum: c990e6a52afe4eaf849fcd1d3d10d3af (MD5) Previous issue date: 2003 / Pires, Victor Flores da Matta / Resumo: A constante busca pela redução dos custos energéticos na indústria petroquímica, proporcionou o desenvolvimento de novas metodologias de otimização energética, dentre as quais se destaca a Análise Pinch. Esta metodologia apresenta bons resultados quando aplicada a processos isolados, porém, quando a análise é estendida a todo um complexo industrial, o resultado final não é satisfatório, uma vez que o sistema de utilidades e a interdependência entre os processos não são considerados. O presente trabalho apresenta a Análise Energética Global ("Total SUe"), que amplia a Análise Pinch da escala de processo para todo o complexo, incluindo o sistema de utilidades como parte integrante do problema, permitindo uma melhor compreensão da interface processo-utilidade, e um aumento do potencial de ganho energético. A metodologia é baseada nos Perfis Térmicos do complexo, obtidos a partir da Análise Pinch de cada processo individual, e sua interação com o sistema de utilidades, que possibilita a determinação das metas de consumo total de combustível, vapor, refrigeração, trabalho de co-geração e emissões atmosféricas do complexo. Com estas metas, é possível obter diagnósticos claros da eficiência energética do complexo, mostrando possibilidades de otimização, mesmo em unidades como alto grau de integração e eficiência energética. No trabalho ainda é proposta uma abordagem especial para as utilidades importadas e exportadas pela central de utilidades do complexo. A Análise Energética Global é aplicada a uma central de matérias pnmas e utilidades de um Polo Petroquímico, para cálculo de suas metas de energia. Também é realizado uma série de estudos abordando paradas de unidades; entrada em operação de nova unidade; modificações de processo; e modificações no sistema de utilidades. Os resultados obtidos confirmam a metodologia como uma excelente ferramenta de análise, que pode ser utilizada tanto na fase inicial do projeto, para auxiliar a construção da melhor configuração energética do complexo, como em complexos existentes, na análise de impactos no seu perfil energético, causados por mudanças nos processos / Abstract: The constant search of energy costs reduction in the petrochemical industry, provided the development of new energy optimization methodologies, which Pinch Analysis stand out. However, the goods results achieved in single process, with this methodology, were not materialised at the site boundary. This problem is caused by the interdependence of the processes and the utility sistem, that are neglected. The present work presents the Total Site Analysis, that extends Pinch Analysis from process leveI to site level, including the utilitiy system as a part of the problem, providing a better understanding of process-utility interface, and increasing the potential of energy profit. The methodology is based on the site's Thermal Profiles, build from Pinch Analysis of each individual process, and its interaction with the utilities system, that makes possible the determination of the targets of fuel consumption, steam, refrigeration, cogeneration work and emissions of the site. With these targets, is possible to obtain a clear diagnostic of the energy efficiency of the site, showing optimization possibilities, for even units with a high degree of integration and energy efficiency. The work presents a special approach to handle the imported and exported utilities by the site's utilities central. The Total Site Analysis is applied to a raw material and utilities central of a Petrochemical Complex, for calculation of its energy targets. Also, a series of studies is carried through, approaching stops of units; start-up of new units; process modifications; and utilities system modifications. The results confirm the methodology as''tll excellent analysis tool, that can be used as in the initial phase of the project, to assist the construction of the best energy configuration ofthe site, as in existing sites, to analyse site's energy profile impacts, caused by changes in the processes / Mestrado / Sistemas de Processos Quimicos e Informatica / Mestre em Engenharia Química

Interfacial instabilities and wetting phenomena of phase separated colloid-polymer mixtures are addressed in this study. Colloidal particles offer certain advantages over molecular systems, due to their larger lengthscales and slower timescales. Moreover, the phenomena can be directly visualised using laser scanning confocal microscopy, and a perfect match with soft-lithography fabrication techniques can be exploited. In particular, we study the viscous fingering instability in three dimensions, focusing on the role of wetting conditions and of thermal fluctuations. Combined with results obtained by lattice Boltzmann simulations, we reveal that the cross-over of the meniscus in the direction across the channel thickness is controlled by the capillary and Peclet numbers, and viscosity contrast of the system. The curvature of the meniscus has a pronounced effect on the onset of the Saffman-Taylor instability, in which the formation of the viscous fingers is suppressed up to a certain threshold. Furthermore, we investigate a related contact line instability, which leads to entrainment and subsequent droplet pinch-off. A theoretical prediction for the onset of the instability is developed, which shows a good agreement with the experimental observations and yields a method to directly measure the slip length of the interface. The large thermal fluctuations of our interface play an important role in pinch-off events, leading to periodic emission of droplets of similar sizes. Finally, we study wetting phenomena at geometrically sculpted walls. We focus on the shape, the thickness and the radius of curvature of the adsorbed liquid film, and find good agreement with theory. Changing the curvature of the wedge from a flat surface to a capil- lary slit furthermore smoothly connects wetting behaviour and capillary condensation, again in qualitative agreement with theory. Non-equilibrium effects may interfere with the data and are difficult to rule out. We end with recommendations for future work.

The tearing mode (TM) is a resistive instability that can arise in magnetically confined plasmas. The TM can be driven unstable by the gradient of the plasma current. When the mode grows it destroys the magnetic field symmetry and reconnects the magnetic field in the form of a so-called magnetic island. The TMs are inherent to a type of device called the reversed-field pinch (RFP), which is a device for toroidal magnetic confinement of fusion plasmas. In the RFP, TMs arise at several resonant surfaces, i.e. where the field lines and the perturbation have the same pitch angle. These surfaces are closely spaced in the RFP and the neighboring TM islands can overlap. Due to the island overlap, the magnetic field lines become tangled resulting in a stochastic magnetic field, i.e. the field lines fill a volume instead of lying on toroidal surfaces. Consequently, a stochastic field results in an anomalously fast transport in the radial direction. Stochastic fields can also arise in other plasmas, for example, the tokamak edge when a resonant magnetic perturbation (RMP) is applied by external coils. This stochastization is intentional to mitigate the edge-localized modes. The RMPs are also used for control of other instabilities. Due to the finite number of RMP coils, however, the RMP fields can contain sidebands that decelerate and lock the TMs via electromagnetic torques. The locking causes an increased plasma-wall interaction. And in the tokamak, the TM locking can cause a plasma disruption which is disastrous for future high-energy devices like the ITER. In this thesis, the TM locking was studied in two RFPs (EXTRAP T2R and Madison Symmetric Torus) by applying RMPs. The experiments were compared with modern mode-locking theory. To determine the viscosity in different magnetic configurations where the field is stochastic, we perturbed the momentum via an RMP and an insertable biased electrode. In the TM locking experiments, we found qualitative agreement with the mode-locking theory. In the model, the kinematic viscosity was chosen to match the experimental locking instant. The model then predicts the braking curve, the short timescale dynamics, and the mode unlocking. To unlock a mode, the RMP amplitude had to decrease by a factor ten from the locking amplitude. These results show that mode-locking theory, including the relevant electromagnetic torques and the viscous plasma response, can explain the experimental features. The model required viscosity agreed with another independent estimation of the viscosity. This showed that the RMP technique can be utilized for estimations of the viscosity. In the momentum perturbation experiments, it was found that the viscosity increased 100-fold when the magnetic fluctuation amplitude increased 10-fold. Thus, the experimental viscosity exhibits the same scaling as predicted by transport in a stochastic magnetic field. The magnitude of the viscosity agreed with a model that assumes that transport occurs at the sound speed -- the first detailed test of this model. The result can, for example, lead to a clearer comparison between experiment and visco-resistive magnetohydrodynamics (MHD) modeling of plasmas with a stochastic magnetic field. These comparisons had been complicated due to the large uncertainty in the experimental viscosity. Now, the viscosity can be better constrained, improving the predictive capability of fusion science. / <p>QC 20171122</p>

Renewability and the carbonaceous basis of biomass provide potential for both energy and chemical production in biorefineries in a fashion similar to crude oil refineries. Biorefineries are envisaged as having a key role in the transition to a more sustainable industry, especially as a means to mitigate greenhouse gas (GHG) emissions. A biorefinery is a concept for the flexible, efficient, cost-effective and sustainable conversion of biomass through a combination of process technologies into multiple products. This implies that biorefineries must be integrated through designs that exploit the interactions between material and energy streams. The wide range of possibilities for biomass feedstock, processes and products poses a challenge to biorefinery design. Integrating biorefineries within evolving economic and environmental policy contexts requires careful analysis of the configurations to be deployed from early in the design stage. This research therefore focuses on the application and development of methodologies for biorefinery design encompassing process integration tools, economic and environmental sustainability analyses together. The research is presented in the form of papers published or submitted to relevant peer-reviewed journals, with a preamble for each paper and a final synthesis of the work as a whole. In a first stage, mass pinch analysis was adapted into a method for integration ofbiorefineries producing bioethanol as a final product and also utilising bioethanol asa working fluid within the biorefinery. The tool allows targeting minimum bioethanol utilisation and assessing network modifications to diminish revenue losses. This new application could stimulate the emergence of similar approaches for the design of integrated biorefineries. The thesis then moves to combine feedstock production models, process simulations in Aspen Plus® and process integration with LCA, to improve energy efficiency and reduce GHG emissions of biorefineries. This work, presented via two publications covering wheat to bioethanol and Jatropha to biodiesel or green diesel, provided evidence of the benefits of biorefinery integrationfor energy saving and climate change adaptation. The multilevel modelling approach is then further integrated into a methodologydeveloped for the combined evaluation of the economic potential and GHG emissions saving of a biorefinery from the marginal performances of biorefineryproducts. The tool allows assessing process integration pathways and targeting forpolicy compliance. The tool is presented via two further publications, the first drawing analogies between value analysis and environmental impact analysis inorder to create the combined Economic Value and Environmental Impact (EVEI)analysis methodology, the second extending this to demonstrate how the tool canguide judicious movement of environmental burdens to meet policy targets. The research embodied in this thesis forms a systematic basis for the analysis andgeneration of biorefinery process designs for enhanced sustainability. The toolspresented will facilitate both the implementation of integrated biorefinery designsand the cultivation of a community of biorefinery engineers for whom suchintegrated thinking is their distinctive and defining attribute.

En este estudio se han construido dos diferentes instalaciones para investigar primero los chorros de gas horizontales y en segundo lugar los chorros verticales de agua que impactan sobre superficies libres de fluido, también se ha desarrollado un modelo numérico integral para predecir las trayectorias de estos jets y sus parámetros más importantes, validándose con los resultados experimentales obtenidos. En la primera parte de este trabajo, se han realizado experimentos para investigar el comportamiento de chorros de gas horizontales penetrando en agua. Los resultados experimentales indicaron que la longitud de penetración de los chorros de gas está fuertemente influenciada por el diámetro de la boquilla y el número de Froude, así como con el flujo de masa de de entrada y su momento. Aumentar el número de Froude y el diámetro del inyector lleva a aumentar la inestabilidad de jet. Además, la máxima ubicación antes de jet pinch-off se muestra que mantiene una relación logarítmica con el número de Froude para todos los diámetros de jet. Se han desarrollado correlaciones empíricas para predecir estos parámetros. Se ha desarrollado un modelo basado en la integración de las ecuaciones de conservación para que resulte útil en el diseño de aplicaciones en las que participen chorros horizontales así como para asistir a la investigación experimental. Las predicciones del modelo integral se comparan con los datos de los datos experimentales obtenidos con muy buenos resultados. En la segunda parte de este trabajo, se realizaron una serie de experimentos con de chorros de agua, inyectados verticalmente hacia abajo, a través de toberas circulares que impactan sobre una superficie de agua. Los resultados obtenidos mostraron que la profundidad de penetración de la burbuja disminuye con la longitud del chorro, pero que después de ciertas condiciones se mantiene casi constante. Además ésta aumenta con los diámetros de la boquilla y la velocidad del chorro. La velocidad de arrastre / Harby Mohamed Abd Alaal, K. (2012). Experimental and Theoretical Study of the Characteristics of Submerged Horizontal Gas Jets and Vertical Plunging Water Jets in Water Ambient [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/18065 / Palancia

[ES] Las regulaciones medioambientales imponen el uso de refrigerantes con cada vez menor Poder de Calentamiento Atmosférico (PCA), y obligan a que la búsqueda de refrigerantes alternativos a los actuales sea una necesidad real acorde a las tendencias del sector. El paso de los refrigerantes actuales a la utilización de refrigerantes alternativos no es inmediato ni mucho menos sencillo. La complejidad a nivel tecnológico es muy elevada, dado que el uso de un nuevo refrigerante exige diseñar y desarrollar de cero todos los componentes del circuito, puesto que poseen unas especificaciones y requerimientos de funcionamiento totalmente diferentes de los que poseen los refrigerantes actuales. La motivación principal de la tesis doctoral es la de plantear lo primeros pasos para el desarrollo de un equipo de bomba de calor para climatización que utilice un refrigerante con un bajo índice de PCA como el propano, en sustitución del que emplea la unidad actualmente (R410A), reduciendo así el impacto medioambiental del equipo y mejorando sus propiedades. Todo esto se encuentra incluido en los siguientes puntos: - Anticipar el cambio de tecnología necesario para el cumplimiento de la regulación F-GAS, asegurando menores emisiones para el medio ambiente y manteniendo la eficiencia energética actual mediante el desarrollo de equipos de bomba de calor con capacidad de modulación y con propano como fluido refrigerante. - Desarrollar herramientas de modelado y simulación para las diferentes plataformas objetivo. - Obtener conocimiento específico sobre el comportamiento de la bomba de calor mediante el análisis experimental con prototipos funcionales bajo las condiciones de trabajo especificadas, con la intención de conocer su funcionamiento, además de sus limitaciones, exigencias prácticas y sus necesidades de control. - Facilitar el diseño y desarrollo industrial de nuevos equipos de climatización mediante las herramientas de simulación y los datos experimentales obtenidos a través de prototipos funcionales. Motivada por este nuevo escenario, esta tesis se centra en estudiar qué posibilidades existen en medio-largo plazo en el desarrollo de bombas de calor para ajustarse a la regulación existente, no solo en cuanto a requerimientos ambientales sino también energéticos. Para ello, el primer paso ha sido el de realizar una sustitución directa del refrigerante original de la unidad aerotérmica, el R410A, por R290 para establecer el punto de referencia y poder conocer qué prestaciones es capaz de desarrollar esa misma unidad sin un rediseño del circuito de refrigerante. Tras esta primera evaluación, se ha llevado a cabo un estudio teórico de distintas configuraciones de circuito frigorífico con propano para evaluar las ventajas e inconvenientes entre ellas, con el objetivo de elegir la que mejor se ajuste al cumplimiento de los objetivos marcados. Este estudio se ha efectuado en tres ámbitos distintos: calefacción a baja temperatura, alta temperatura y condiciones de alta temperatura de impulsión de agua hasta 75ºC. En todos ellos, el resultado principal que se ha considerado ha sido el de eficiencia, lo que ha permitido obtener un orden de las tipologías estudiadas en función de los resultados obtenidos. A pesar de esto, esta evaluación también ha puesto de manifiesto otra característica intrínseca a cada uno de ellos como es su límite de funcionamiento en relación con la máxima temperatura de impulsión de calefacción. Tras ello, se ha construido un prototipo de bomba de calor funcional completo para ejecutar la fase experimental, que incluya hasta tres de las tipologías evaluadas en la fase teórica previa, para que, con todos los ensayos pertinentes, los resultados permitan seleccionar la tipología de circuito de refrigerante que se integre en un prototipo final. Este prototipo permitirá caracterizar el funcionamiento del sistema tanto para una plataforma aire-agua, como para una plataforma salm / [CA] Les regulacions mediambientals imposen l'ús de refrigerants amb cada vegada menor Poder d'Escalfament Atmosfèric (PCA), i obliguen a que la recerca de refrigerants alternatius als actuals sigui una necessitat real d'acord amb les tendències del sector. El pas dels refrigerants actuals a l'utilització de refrigerants alternatius no és immediat ni tampoc fàcil. La complexitat a nivell tecnològic és molt elevada, ja que l'ús d'un nou refrigerant exigeix dissenyar i desenvolupar de zero tots els components del circuit, tenint en conta que tenen unes especificacions i requeriments de funcionament totalment diferents dels que posseeixen els refrigerants actuals. La motivació principal de la tesi doctoral és la de plantejar el primers passos per al desenvolupament d'un equip de bomba de calor per a climatització que utilitzi un refrigerant amb un baix índex de PCA com el propà, en substitució del què empra la unitat actualment (R410A), reduint així l'impacte mediambiental de l'equip i millorant les seves propietats. Tot això es troba inclòs en els següents punts: - Anticipar el canvi de tecnologia necessari per al compliment de la regulació F-GAS, assegurant menors emissions per al medi ambient i mantenint l'eficiència energètica actual mitjançant el desenvolupament d'equips de bomba de calor amb capacitat de modulació i amb propà com a fluid refrigerant. - Desenvolupar ferramentes de modelatge i simulació per a les diferents plataformes objectiu. - Obtenir el coneixement específic sobre el comportament de la bomba de calor mitjançant l'anàlisi experimental amb prototips funcionals en les condicions de treball especificades, amb la intenció de conèixer el seu funcionament, a més de les seues limitacions i exigències pràctiques i les seues necessitats de control. - Facilitar el disseny i desenvolupament industrial de nous equips de climatització mitjançant les ferramentes de simulació i les dades experimentals obtingudes a través de prototips funcionals. Motivada per aquest nou escenari, aquesta tesi es centra a estudiar quines possibilitats hi ha al mitjá-llarg termini en el desenvolupament de bombes de calor per a ajustar-se a la regulació existent, no només en relació amb el requeriments ambientals sinó també energètics. Per això, el primer pas ha sigut el de fer una substitució directa del refrigerant original de la unitat aerotèrmica, el R410A, per R290 per establir el punt de referència i poder conèixer quines prestacions és capaç de desenvolupar aquesta mateixa unitat sense un redisseny del circuit de refrigerant. Després d'aquesta primera avaluació, s'ha dut a terme un estudi teòric de diferents configuracions de circuit frigorífic amb propà per avaluar els avantatges i inconvenients entre elles, amb l'objectiu de triar la que millor s'ajusti a l'acompliment dels objectius marcats. Aquest estudi s'ha efectuat en tres àmbits diferents: calefacció a baixa temperatura, alta temperatura i condicions d'alta temperatura d'impulsió d'aigua fins a 75ºC. En tots ells, el resultat principal que s'ha considerat ha sigut el d'eficiència, el que ha permès obtenir un ordre de les tipologies estudiades en funció dels resultats obtinguts. Tot i això, aquesta avaluació també ha posat de manifest una altra característica intrínseca a cada un d'ells com és el seu límit de funcionament en relació amb la màxima temperatura d'impulsió de calefacció. Després d'això, s'ha construït un prototip de bomba de calor funcional complet per executar la fase experimental, que inclogui fins a tres de les tipologies avaluades en la fase teòrica prèvia, perquè, amb tots els assajos pertinents, els resultats permeten seleccionar la tipologia de circuit de refrigerant que s'integri en un prototip final. Aquest prototip permetrà caracteritzar el funcionament de sistema tant per a una plataforma aire-aigua, com per a una plataforma salmorra-aigua, a través del canvi del bescanviador / [EN] Environmental regulations impose the use of refrigerants with less and less Global Warming Potential (GWP), and force that the search for alternative refrigerants in order to substitute the current ones is a real need according to the trends in the sector. The transition from current refrigerants to the use of alternative refrigerants is neither immediate nor simple. The complexity at the technological level is very high, since the use of a new refrigerant requires a new design and a new development for all the components along the refrigerant circuit, since they may have totally different specifications and operating requirements compared to the traditional refrigerants. The main motivation of this thesis is to present the initial stages concerning the development of a heat pump unit for space heating that uses a lo GWP refrigerant like propane, replacing the current refrigerant of the unit (R410A), leading to a reduction of the environmental impact of this equipment and improving its properties. All this has been included on the following points: - Anticipate the required technology change to be compliant with the F-GAS regulation, ensuring low-impact emissions to the atmosphere and keeping a similar energy efficiency through the development of heat pump units with heating capacity modulation and with propane as refrigerant. - Develop modelling and simulation tools for the different platforms approaches. - Obtain specific knowledge about the heat pump performance through experimental analysis with functional prototypes under the specified working conditions, with the aim of acquiring knowledge not only about its operation, but also about its limitations, practical requirements and its control needs. - Contribute to the industrial design and development of new space heating equipment using simulation tools and experimental data obtained through functional prototypes. Motivated by this new scenario, this thesis focuses on studying the available options in the medium-long term concerning the heat pump development in order to be compliant with the applicable regulations, not only in terms of environmental requirements but also energy requirements. To do this, the first step has been related to carry out a direct replacement of the original refrigerant of the aerothermal unit, R410A, with R290 to establish the reference point and to be able to know the performance of the original unit without considering a redesign of the refrigerant circuit. After this initial evaluation, a theoretical study of different refrigerant circuit configurations with propane has been carried out with the purpose of evaluating the advantages and disadvantages among them, in order to choose the one that fulfils the performance requirements the best. This study has been executed in three different areas: low heating temperature, high heating temperature and high water flow temperature conditions up to 75ºC. In all of them, the main result considered has been the efficiency, which has enabled to obtain a priority order based on the results obtained. Despite this, this evaluation has also revealed another attached feature, such as their operating limit in relation to the maximum heating flow temperature. After that, a complete functional heat pump prototype has been built to execute the experimental phase, which includes up to three of the typologies evaluated in the previous theoretical phase, so that, with all the corresponding tests, the results allow to select the typology of refrigerant circuit to be integrated into a final prototype. This prototype has also enabled the performance characterization for two different types of platforms, air-water and brine-water, by changing of the corresponding exchanger using cutting valves. In parallel to this, a certain phenomenon related to the behaviour of the refrigerant have been studied through different operating conditions for each typology as well as the proper measures to improve the system control. As / López Juárez, E. (2021). Desarrollo de una bomba de calor doméstica que usa propano como fluido de trabajo [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/174570 / TESIS

This thesis deals with the experimental study of magnetorheological shaft seal. The purpose of this diploma thesis is to describe the operating parameters of rotational magnetoreological shaft seal. In thesis, the effects of magnetic field and shaft speed on the pressure resistance and braking torque are described. Operating parameters were measured by an experimental device. Research has shown that the magnetoreological seal is characterized by a high pressure resistant. Disadvantages are the high braking torque and leakage of carrier oil from the magnetorheological fluid. These problems have been solved by a new design of magnetic circuit, that has been identified as a magnetoreological gradient pinch seal (MRGPS).

Magnetically confined fusion (MCF) plasmas are typically subject to several unstable modes. The growth of one mode can limit the plasma energy confinement and might cause a termination of the plasma. Externally applied resonant magnetic perturbations (RMPs) are used to control and to mitigate some of the unstable modes. Examples are, mitigation of edge localized modes and steering of neoclassical tearing mode position for stabilization by electron cyclotron current drive. Consequently, use of RMPs are considered necessary in planned future fusion machines. There are however negative consequences, the RMP interaction with a tearing mode (TM) of the same resonance can cause deceleration of the TM and possibly wall-locking. If a TM is non-rotating relative the machine-wall, it can grow and degrade fusion plasma performance and lead to a plasma disruption. Thus, all fusion confinement machines want to avoid wall-locked modes. Resonant magnetic fields can also be present in the form of machine-error-fields, which can produce the same effects. Clearly, it is of importance to understand the TM-RMP interaction. Typically, the modes with long wavelength are described by magnetohydrodynamic (MHD) theory. Considering the finite plasma resistivity, MHD predicts a mode that tears and reconnects magnetic field lines, called a tearing mode (TM). TMs occur at surfaces where the magnetic field lines close on themselves after a number of (m) toroidal and (n)poloidal turns. These surfaces are resonant in the sense that magnetic field and helical current perturbation has the same helicity, which minimize stabilizing effect of magnetic field line bending. In this thesis, the mechanisms of TM locking and unlocking due to external resonant magnetic perturbations (RMPs) are experimentally studied. The studies are conducted in two MCF machines of the type reversed-field pinch (RFP): EXTRAP T2R and Madison Symmetric Torus (MST). The studied machines exhibit multiple rotating TMs under normal operation. In EXTRAP T2R TM locking and unlocking are studied by application of a single harmonic RMP. Observations show that after the TM is locked, RMP amplitude has to be reduced significantly in order to unlock the TM. In similar studies in MST unlocking is not observed at all after turn-off of the RMP. Hence, in both machines, there is hysteresis in the locking and subsequent unlocking of a tearing mode. Results show qualitative agreement with a theoretical model of the TM evolution when subjected to an RMP. It is shown that the RMP cause a reduction of TM and plasma rotation at the resonant surface. The velocity reduction is opposed by a viscous torque from surrounding plasma. After TM locking, relaxation of the whole plasma rotation is observed, due to the transfer of velocity reduction via viscosity. This results in a reduced viscous resorting torque, which explains the observed hysteresis. The hysteresis is further deepened by the increase in amplitude of a locked mode. / <p>QC 20160111</p>

The report comprises two separate parts: part 1:  Temperature needs for district heating in the paint shop for axles in building 210 part 2:  Energy and low temperature waste heat solutions in heating and cooling systems for   building 64 with surroundings The paint shop for axles in part 1 has air quality requirements in places for coating of axles. Toachieve desired air properties there are different process ventilation systems, which consist ofventilation coils for heating and cooling, plus air humidifier. The ventilations coils for heating usedistrict heating. Today the ventilation coils use water of 100°C to achieve necessary air demands inthe coating boxes. This part of the report investigates whether the existing system would achievethe air requirements with a water temperature of 75°C instead of 100°C in the ventilation coilsduring the coldest parts of the year. The conclusion is that it is not possible; the existing system isadjusted for a water temperature of 100°C to achieve the air requirements. To use a watertemperature of 75°C, more or major ventilation coils are needed. The focus of the report is at part 2. In this part, possibilities for low temperature waste heatsolutions are investigated. Those partly aim at specific local solutions for building 64 withsurroundings and on the other part of general waste heat solutions for new buildings andreconstructions in the future. To make these parts possible, the systems for heating and cooling inbuilding 64 have been identified. During this identification, potential savings that are not of wasteheat character have also been observed. The most profitable saving concerns the control of temperature for the inner hardening vat. It isthe hardening vat for gas carburizing oven SV16838 that has been studied in this report. Today thetemperature of the hardening vat is controlled very ineffective. The conclusion is that a betteradjustment of the controller would save 180 000 SEK/year with a pay off time around two months.Worth mentioning (SV16838 included), is that there are at least five similar gas carburizing ovens atthe Scania area in Södertälje. A pinch analysis has also been done for building 64, with it’s primarily conclusion that the groundheating is violating the pinch rules during long periods of the year. To remedy the ground heatingwill only need a different control and will lead to a saving between 20 000 – 75 000 SEK/year. Tomore accurate determine the saving, an investigation of the ground heating during winter time isneeded. Another conclusion concerning the pinch analysis is that the method for a real scenariorather shows the potential of the system than gives you an optimal solution possible to implement.More actions are to use the exhaustions of the endo gas generators and that the washing andrinsing systems if possible not should be heated with electricity. The exhaustions from the endo gasgenerators have a very high temperature, more then 300°C. If these, instead of hot water boilers,could warm the closely located water for the LPG (liquefied petroleum gas) evaporation, 125 000SEK/year can be saved. Today the hot water boilers are heated with electricity. If the washing andrinsing systems existing electricity heating instead can be heated with secondary heat (˜ districtheating), a save of 500 000 SEK/year is possible. For waste heat solutions there are a few different approaches. Close to building 64, the largestpotential to use waste heat is in building 62 and 75, where air heaters are assessed with the largestpotential. In difference to other investigated buildings, building 210 has the possibility to use wasteheat even during the summer. This building is located 1 km from building 64. To use waste water inbuilding 210, a complex net of waste heating will be required where several buildings with asurplus of waste heat can be connected. A net like this has calculated pipe costs of 5, 2 million SEK.The saving for the use of waste heat only in building 210 will be around 1,4 million SEK/year. Thissave corresponds to the air handling systems that occur in part 1.