Master of Science / Department of Mechanical and Nuclear Engineering / Kirby S. Chapman / The purpose of this thesis is to present on the development and results of the cooling system logic tree and model developed as part of the Pipeline Research Council International, Inc (PRCI) funded project at the Kansas State National Gas Machinery Laboratory. PRCI noticed that many of the legacy engines utilized in the natural gas transmission industry were plagued by cooling system problems. As such, a need existed to better understand the heat transfer mechanisms from the combusting gases to the cooling water, and then from the cooling water to the environment. To meet this need, a logic tree was developed to provide guidance on how to balance and identify problems within the cooling system and schedule appropriate maintenance. Utilizing information taken from OEM operating guides, a cooling system model was developed to supplement the logic tree in providing further guidance and understanding of cooling system operation. The cooling system model calculates the heat loads experienced within the engine cooling system, the pressures within the system, and the temperatures exiting the cooling equipment. The cooling system engineering model was developed based upon the fluid dynamics, thermodynamics, and heat transfer experienced by the coolant within the system. The inputs of the model are familiar to the operating companies and include the characteristics of the engine and coolant piping system, coolant chemistry, and engine oil system characteristics. Included in the model are the various components that collectively comprise the engine cooling system, including the water cooling pump, aftercooler, surge tank, fin-fan units, and oil cooler. The results of the Excel-based model were then compared to available field data to determine the validity of the model. The cooling system model was then used to conduct a parametric investigation of various operating conditions including part vs. full load and engine speed, turbocharger performance, and changes in ambient conditions. The results of this parametric investigation are summarized as charts and tables that are presented as part of this thesis.

Large depression cone in water table was formed due to mining in surroundings of Střeleč quarry. The concentrated inflow from conduits to quarry is up to 70 l/s. Large conduit systems are created by flowing water into the quarry. The biggest conduit system was at least 300 m long and 17 m high with maximum calculated volume of 22 thousands m3 . Evolution of these conduits usually takes several months to few years. Fast conduit evolution allows to study erosion processes in detail in situ. In the thesis I am describing conduits, character of flow and erosion processes. Measured flow velocities in conduits are up to 0,4 m/s with hydraulic gradient 1 to 5%. Flow velocities and hydraulic gradients are typical for piping erosion. Piping initially forms small protoconduits. The bigger conduits are formed as water is progressively drained from larger area. Conduits are following fracture surfaces, which are also limiting the conduit propagation to the sides. Above water table the conduits are enlarged mainly by mass wasting of undercut sandstone slabs. For distinguishing less and more erodible parts of sandstone, we adapted and partially developed a method for measuring erodability (REI) and drilling resistance (DR). Both are used to compare different types of sandstone surfaces. In lowermost part of the...

En 2014, le réseau de pipelines à travers le monde est estimé à près de 3 500 000 km. Ces conduites en acier traversent plusieurs continents, régions, climats et donc différents types de sols. Elles sont protégées contre la corrosion externe par des revêtements et une protection cathodique. Néanmoins, il subsiste toujours un risque infime de dégradation de l’acier. Afin d’évaluer le risque de rupture d’une conduite, il est nécessaire d’étudier l’influence du sol sur la corrosion de l’acier nu non protégé composant cette conduite. Les paramètres régissant la corrosion des aciers dans les sols étant nombreux, nous nous sommes focalisés sur l’un des paramètres clés, à savoir « la teneur en eau » qui est directement reliée à d’autres paramètres très influents comme : l’aération ou taux d’oxygène, la résistivité du sol et la surface active. Dans cette thèse, nous nous sommes intéressés aux phénomènes se produisant lors de périodes transitoires de séchage/humidification de plusieurs types de sols : argileux, limoneux argileux et sableux. Une électrode multi-coupons a aussi été utilisée afin d’étudier les phénomènes liés à l’hétérogénéité de surface (formation de piles d’aération différentielle). Pour cela, différents coupons en acier provenant d’une conduite d’Air Liquide ont été enfouis pendant de longues périodes (4, 6 et 12 mois) dans différents types de sols. Les vitesses de corrosion sont estimées par électrochimie via la modélisation des courbes de voltammétrie autour du potentiel d’abandon. La surface active de l’électrode est estimée via la mesure de la résistance d’électrolyte par spectroscopie d’impédance électrochimique. Les échantillons sont ensuite analysés par micro-spectroscopie Raman, diffraction des rayons X et microscopie (optique, confocale et électronique à balayage) afin de déduire les mécanismes de corrosion de l’acier. Les résultats montrent, notamment, qu’en cas d’un fort taux d’humidité et d’une faible aération, les vitesses de corrosion sont très faibles (de l’ordre de 20 à 30 µm.an-1) mais atteignent 200 à 400 µm.an-1 lors des phases de séchage. La mesure de courants de couplage effectuée avec l’électrode multi-coupons ainsi que l’analyse de surface des coupons conventionnels ont confirmé la présence de piles d’aération différentielle et le caractère localisé de la corrosion. / In 2014, the pipelines network extended over 3500000 km worldwide. These pipes are passing through various continents, regions, areas and thus different types of soils. They are protected against external corrosion by coatings and cathodic protection. However, there is always a slight risk of carbon steel degradation. In order to evaluate the pipeline failure threat, it is necessary to study the influence of soil corrosion on the uncoated steel which composes this pipe. There are many parameters governing the steel corrosion in soils. We focused on one of the most important parameter “water content”. It is directly linked to other prominent parameters such as oxygen concentration, soil resistance and active area. In this thesis, we addressed the phenomena occurring at transitory periods of drying and remoistening in different types of soils : clayey, silt-loamy and sandy. A multi-coupon electrode was used as well in order to study the phenomena linked to surface heterogeneity (formation of differential aeration cells). For this aim, several steel coupons were buried in different types of soil for long periods (4, 6 and 12 months). The corrosion rates are estimated via electrochemical methods by fitting with a theoretical law the voltammetric curves acquired around the open circuit potential. The active area of the electrode was estimated via the determination of the soil electrolyte resistance by electrochemical impedance spectroscopy. Afterwards, the coupons were analyzed by micro-spectroscopy Raman, X-rays diffraction and microscopy in order to understand the corrosion mechanisms. Results showed that in case of very high moisture content and deaerated conditions, the corrosion rates were very weak (about 20 to 30 µm.yr-1) but reached 200 to 400 µm.yr-1 in the drying periods. The galvanic current measurements performed with the multi-coupon electrode and the surface analysis of the conventional electrodes both confirmed the presence of differential aeration cells and the localized nature of the corrosion.

Embedded systems are becoming ubiquitous, primarily due to the fast evolution of digital electronic devices. The design of modern embedded systems requires systems to exhibit, high performance and reliability, yet have short design time and low cost. Application Specific Instruction set processors (ASIPs) are widely used in embedded system since they are economical to use, flexible, and reusable (thus saves design time). During the last decade research work on ASIPs have been carried out in mainly for single pipelined processors. Improving performance in processors is possible by exploring the available parallelism in the program. Designing of multiple parallel execution paths for parallel execution of the processor naturally incurs additional cost. The methodology presented in this dissertation has addressed the problem of improving performance in ASIPs, at minimal additional cost. The devised methodology explores the available parallelism of an application to generate a multi-pipeline heterogeneous ASIP. The processor design is application specific. No pre-defined IPs are used in the design. The generated processor contains multiple standalone pipelined data paths, which are not necessarily identical, and are connected by the necessary bypass paths and control signals. Control unit are separate for each pipeline (though with the same clock) resulting in a simple and cost effective design. By using separate instruction and data memories (Harvard architecture) and by allowing memory access by two separate pipes, the complexity of the controller and buses are reduced. The impact of higher memory latencies is nullified by utilizing parallel pipes during memory access. Efficient bypass network selection and encoding techniques provide a better implementation. The initial design approach with only two pipelines without bypass paths show speed improvements of up to 36% and switching activity reductions of up to 11%. The additional area costs around 16%. An improved design with different number of pipelines (more than two) based on applications show on average of 77% performance improvement with overheads of: 49% on area; 51% on leakage power; 17% on switching activity; and 69% on code size. The design was further trimmed, with bypass path selection and encoding techniques, which show a saving of up to 32% of area and 34% of leakage power with 6% performance improvement and 69% of code size reduction compared to the design approach without these techniques in the multi pipeline design.

Darbo metu apžvelgiami metodai pereinamiesiems procesams vamzdyne realizuoti. Aprašyta vamzdyno tėkmės pereinamųjų procesų dinamika matematinės lygtys ir sudarytas baigtinių elementų modelis skaitiniam vamzdynų pereinamųjų procesų modeliavimui. Panaudojant atgalinį slėgio bangos modeliavimą esant idealizuotam slėgio bangos sklidimo modeliui, sudaromas slėgio impulso vietos nustatymo algoritmas ir įvertinamos atsirandančios paklaidos. Realizuota programine įranga patikrinamas sudarytų modelių ir algoritmo teisingumas, bei pateikiami pasiūlymai, atsiradusioms paklaidoms mažinti. / During this research, the methods to realize the transient processes in piping systems are overviewed, also finite element method and idealized wave propagation of pressure mathematical models are set up. Using the backward pressure wave modelling at idealized pressure wave propagation model, piping system rupture location algorithm and the assessment of estimated errors are set up. With released software, the developed models and correctness of the algorithm are verified, and suggestions to reduce the resulting errors are presented.

En ingénierie sismique, il est admis que le comportement d’une structure soumise à de forts séismes soit caractérisé par des boucles d’hystérésis qui peuvent être amples ou étroites selon le type de structure impactée. La prise en compte de ce type de comportement non-linéaire dans un calcul temporel présente des difficultés liées à l’identification des paramètres, au coût numérique élevé, au risque de non-convergence. Dans ce contexte, la méthode de linéarisation équivalente, a été introduite en géotechnique dès les années 70. Elle reste peu utilisée dans le domaine des structures malgré les efforts de nombreux auteurs. Ce travail de thèse a pour objet l’étude du comportement linéaire équivalent dans le contexte des méthodes simplifiées d'évaluation de la réponse non-linéaire d'une structure en ingénierie sismique. Nous passons en revue les critères de linéarisation adoptés par les différentes méthodes qui recherchent l’équivalence (1) du déplacement maximum ou (2) de la quantité d’énergie dissipée ou (3) de la force de rappel. Nos analyses montrent que ces trois critères ne sont pas pertinents et/ou efficaces, conduisant à des méthodes peu robustes qui conduisent dans certains cas à des résultats inexplicables. Nous montrons le rôle important, négligé par toutes les méthodes disponibles, du contenu fréquentiel respectif des signaux et du système dans la détermination de la ductilité appelée. Sur cette constatation, nous introduisons une nouvelle méthode de linéarisation équivalente basée sur la fonction de transfert. Nous utilisons cette méthode pour explorer un plan d’expérience numérique dans lequel nous calculons les caractéristiques de fréquence et d’amortissement équivalents en fonction de la ductilité appelée pour différente configurations caractérisées par (a) le rapport entre fréquence de l’oscillateur et fréquence centrale du signal excitateur, (b) la pente d’écrouissage et (c) le modèle de comportement qui varie continument de élastoplastique à endommageant. Nous proposons deux nouvelles approches du comportement linéaire équivalent. La première, visant à améliorer la procédure statique non-linéaire de l’ATC40, utilise la rigidité sécante et le déplacement maximal. Elle fait intervenir une estimation de l’amortissement différente de celle de l’ATC40. Sa pertinence est établie par le fait qu’elle permet d’évaluer avec exactitude le déplacement maximal de systèmes canoniques non-linéaires. La seconde consiste à restituer la dynamique de la réponse d'un oscillateur non-linéaire au travers de la fonction de transfert. Sa pertinence est démontrée au travers des critères d’Anderson, avec notamment un critère relatif au spectre transféré. La détermination du comportement linéaire équivalent par fonction de transfert est validée sur des structures réelles au travers des essais sur voiles en béton armé (SAFE) et sur systèmes des tuyauteries (BARC et EPRI) / In earthquake engineering, it is common that the behaviour of a structure undergoing a strong motion is characterized by wise or narrow hysteresis loops depending on the type of behaviour of the structure. Considering this non-linear behaviour in a transient calculation requires a huge need of resources in terms of calculation time and memory. In this context, the method of equivalent linearization, consisting in the evaluation of the non-linear response of the structure has been introduced by geotechnical engineers In the 1970s. Despite efforts of many authors, this method is still not used in structural field. The goal of this research is to examine the linear equivalent behaviour in the context of the simplified method of evaluating the non-linear response of a structure in earthquake engineering. We review the criteria of equivalence adopted by many methods searching for the equivalence of (1) the maximum of displacement or (2) quantity of dissipated energy or (3) the restore force. Our argumentative analyses carry out that these three criteria are not pertinent and/or efficient. This leads, in some cases, to some unexplained results. We show the important role, which is mostly neglected in existing method, of frequency content while evaluating the ductile demand. Based on this recognition, we introduce a new method of equivalent linearization based on the transfer function. We use this method in order to explore a numerical experimental plan in which we calculate the equivalent characteristics (frequency and damping) versus the ductile demand for different configuration characterized by (a) the ratio between the frequency of the oscillator and the central frequency of the input signal, (b) the hardening and (c) the behaviour which covers the elastoplastic and damaged ones. We propose two new approaches of the linear equivalent behaviour. The first one, aiming to improve the non-linear static procedure of ATC40, use the secant stiffness and the maximal displacement. This approach consists in an estimation of damping which is different to ATC40. Its pertinence is established by evaluating with accuracy the maximal displacement of the canonical non-linear systems. The second approach consists in restitution of the dynamic of the response of a non-linear oscillator by using the transfer function. The pertinence of this proposition is shown through the criteria of Anderson, especially in terms of transferred motion. In this effect, the linear equivalent behaviour based on the transfer function allows to cope the transferred motion through the non-linear oscillator without performing the non-linear transient calculation. The validation of the linear equivalent behaviour based on the transfer function has been examined on real structures through some experimental tests such as the reinforced concrete wall (SAFE) or piping systems (BARC and EPRI)

The theme of this thesis is to compare free housing with a milking robot, milking of serious housing in the pipeline. The evaluation is focused on milk yield and its quality, reproductive performance and health. It is also monitored by the free choice of milking cows during the day. Consideration is also observed in stable microclimate. Everything is assessed under operational conditions. Object of study is a refurbished barn, where both systems are in operation. Were measured and compared observed values of milk production, reproduction and health status between groups. The observed values were evaluated in the program Statistica 9th of a computerized milking robot system was speciaed the period of time when Nada dairy milk provides the most of milk through a robot.. In the area of dairy cattle milking robot reaches a higher milk yield and increasing the percentage of lactose recovery. Milking stalls of the pipeline has better results in the percentage of protein recovery. The choice of time period of milking cows, the most milk by dairy cows wasprovided between 10:00-18:00 pm. In the area of reproduction achieved better results with loose housing milking robot. The issue of health status showed a statistically better health outcomes for the free housing with a milking robot.

Orientador: Antonio Carlos Bannwart / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica, Instituto de Geociencias / Made available in DSpace on 2018-08-14T16:09:37Z (GMT). No. of bitstreams: 1 Lima_IvanNovilleRochaCorrea_M.pdf: 2854489 bytes, checksum: fec392ec12651861ca4547ea5ce279c9 (MD5) Previous issue date: 2009 / Resumo: O presente trabalho tem por objetivo central a medição experimental do coeficiente de transferência de calor bifásico no padrão gás-líquido horizontal intermitente, por ser este um padrão muito comum nas operações de produção de petróleo. Para alcançar esse objetivo, foi construído um aparato experimental consistindo de uma seção de testes alimentada por uma mistura pré-aquecida de ar e água, a diferentes pares de vazões e temperaturas de entrada. Para realizar a troca térmica, o tubo foi circundado por uma jaqueta de água gelada submetida a diversas vazões e temperaturas de entrada, formando, com o tubo central, uma seção de troca térmica de correntes paralelas. A metodologia experimental consistiu em medir a taxa de transferência de calor do fluido interno para o fluido externo e, a partir da diferença média de temperatura entre o fluido quente e a parede, determinar o coeficiente de transferência de calor entre o fluido quente e a parede, para cada elenco de condições de operação. O procedimento foi realizado tanto para os ensaios em escoamento monofásico como para o escoamento bifásico. Os resultados para o coeficiente de transferência de calor do fluido quente foram comparados às correlações e aos modelos existentes e apresentaram resultados satisfatórios. / Abstract: The main objective of the present work is the experimental measurement of the two-phase heat transfer coefficient in the intermittent horizontal gas-liquid flow pattern. This flow pattern is very common in oil production pipelines. In order to reach this objective, an experimental apparatus was built, consisting of a test section fed with an air-water mixture pre-heated at different pairs of inlet flow rates and temperatures. In order to realize the heat transfer, the pipe was surrounded by a jacket containing cold water under various inlet flow rates and temperatures, forming with the central pipe a heat transfer section of parallel current. The experimental methodology consisted of measuring the heat transfer rate from the internal to the external fluid, and from the average difference of the temperature between the hot fluid and the pipe wall, determine the heat transfer coefficient between the hot fluid and the pipe wall for each cast of operating condition. The procedure was carried through for both single phase and two-phase tests. The results of the heat transfer coefficients between the hot fluid were compared with some correlations and existing models and presented satisfactory results. / Mestrado / Explotação / Mestre em Ciências e Engenharia de Petróleo

Le travail présenté dans ce mémoire de thèse porte sur la modélisation discrète de l’évolution régressive du front d’un conduit d’érosion qui peut se produire dans les barrages ou digues en remblai. Des outils numériques ont été développés en se basant sur le couplage entre la méthode des éléments discrets (DEM) et la méthode de Boltzmann sur réseau (LBM) pour la description, respectivement, des phases solide et fluide. L’implémentation de la méthode DEM suit une approche standard de type dynamique moléculaire (DM) et les interactions intergranulaires sont modélisées par des contacts unilatéraux visco-élastiques frottants ou bilatéraux (ponts solides) viscoélastiques, afin de permettre la modélisation d’un sol légèrement cohésif. La méthode LBM est implémentée ici avec des temps de relaxation multiples (MRT) et une condition de rebondissement interpolée pour les frontières solides en mouvement, afin d’améliorer la stabilité numérique des calculs. Le schéma du couplage entre les deux méthodes, ainsi que les critères pour le choix des paramètres numériques des deux méthodes. Pour étudier le phénomène visé, un échantillon représentatif de sol granulaire situé au front d’un conduit d’érosion est d’abord assemblé par une procédure de préparation “à sec”, puis testé dans des conditions saturées sous un chargement hydraulique monotone croissant. L’érosion régressive se produit par amas de grains au niveau du front d’érosion ayant subi au préalable une dégradation due à de nombreuses ruptures de ponts solides en traction. L’autre phénomène important observé est la présence d’arcs associés a` des chaines de forces en compression qui parviennent à maintenir parfois totalement, parfois partiellement l’intégrité du matériau non érodé. / The work reported in this thesis consists in a discrete modelling of the backward front propagation of an erosion pipe, as can take place in embankment dams or dikes. Some numerical tools have been developed to this end, based on the coupling between the Discrete Element Method (DEM) and the Lattice Boltzmann Method (LBM) for the representation of the solid and uid phases, respectively. The implementation of DEM follows a standard molecular dynamics approach and the interaction among grains are regulated by unilteral frictional visco-elastic and breakable visco-elastic bonds, in order to take into account a slightly cohesive soil behaviour. The LBM was implemented according to the Multiple Relaxation Time (MRT) scheme along with an interpolated non-slip conditions for moving boundaries, in order to improve the numerical stability of the calculations. The coupling scheme is described along with the criteria for the numerical parameters of the two methods. A representative specimen of a granular soil located at the front of an erosion pipe is first assembled by a \dry" preparation precedure and then tested under fully-saturated conditions and increasing hydraulic load over time. Backward erosion is takes place in the form of clusters of grain being eroded at the erosion front after a degradation of the material due to the breakage of tensile bonds. The other interesting feature that was observed is the creation of arches of compressive force chains. These arches enabled the specimen to maintain a stable or metastable configuration under the increasing hydraulic load.

Tato práce se zabývá využitím distribucí neboli zobecněných funkcí k řešení nestacionárních okrajových problémů v mechanice kontinua. Nejprve je zavedena teorie distribucí a jejich definice jako spojitých lineárních funkcionálů na prostoru testovacích funkcí. Druhá část teoretické kapitoly představuje Laplaceovu integrální transformaci. Následující kapitola se věnuje řešení průhybu nosníků pod vlivem nespojitého časově proměnlivého zatížení. Jejím výsledkem je vytvoření obecného modelu řešení průhybových čar nosníků vužitím distribucí. Poslední kapitola se zabývá řešením nestacionárního proudění v trubicích spojených hydraulickými prvky.