Dissertations / Theses: 'Turbomachinery'

1

Görling, Martin. "Turbomachinery in Biofuel Production." Licentiate thesis, KTH, Energiprocesser, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-28901.

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The aim for this study has been to evaluate the integration potential of turbo-machinery into the production processes of biofuels. The focus has been on bio-fuel produced via biomass gasification; mainly methanol and synthetic natural gas. The research has been divided into two parts; gas and steam turbine applications. Steam power generation has a given role within the fuel production process due to the large amounts of excess chemical reaction heat. However, large amounts of the steam produced are used within the production process and is thus not available for power production. Therefore, this study has been focused on lowering the steam demand in the production process, in order to increase the power production. One possibility that has been evaluated is humidification of the gasification agent in order to lower the demand for high quality steam in the gasifier and replace it with waste heat. The results show that the power penalty for the gasification process could be lowered by 18-25%, in the specific cases that have been studied. Another step in the process that requires a significant amount of steam is the CO2-removal. This step can be avoided by adding hydrogen in order to convert all carbon into biofuel. This is also a way to store hydrogen (e.g. from wind energy) together with green carbon. The results imply that a larger amount of sustainable fuels can be produced from the same quantity of biomass. The applications for gas turbines within the biofuel production process are less obvious. There are large differences between the bio-syngas and natural gas in energy content and combustion properties which are technical problems when using high efficient modern gas turbines. This study therefore proposes the integration of a natural gas fired gas turbine; a hybrid plant. The heat from the fuel production and the heat recovery from the gas turbine flue gas are used in a joint steam cycle. Simulations of the hybrid cycle in methanol production have shown good improvements. The total electrical efficiency is increased by 1.4-2.4 percentage points, depending on the fuel mix. The electrical efficiency for the natural gas used in the hybrid plant is 56-58%, which is in the same range as in large-scale combined cycle plants. A bio-methanol plant with a hybrid power cycle is consequently a competitive production route for both biomass and natural gas.
QC 20110128

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2

Sheard, Anthony Geoffrey. "Innovation in industrial turbomachinery." Thesis, Aston University, 2015. http://publications.aston.ac.uk/28116/.

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3

Medd, Adam Jon. "Inverse design of turbomachinery blades." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0010/MQ34391.pdf.

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4

Borges, J. E. "Three-dimensional design of turbomachinery." Thesis, University of Cambridge, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.384285.

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5

Neal, P. M. "Data acquisition for turbomachinery (MORDAS)." Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.282719.

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6

Cooke, Adam. "Turbomachinery disc heat transfer uncertainty." Thesis, University of Sussex, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.442442.

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7

Molinari, Massimiliano. "Reduced order modelling for turbomachinery." Thesis, University of Cambridge, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.608710.

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8

Evers, Ingmar. "Sound generation in turbomachinery flow." Thesis, University of Cambridge, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.624316.

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9

Sieburg, H. O. "Creep predictions for turbomachinery components." Master's thesis, University of Cape Town, 1989. http://hdl.handle.net/11427/18697.

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Several theories of creep and creep rupture are reviewed. Specific attention is devoted to the brittle damage theory proposed by Kachanov. Creep, damage and life predictions for rectangular or circular cross section beams under bending and tensile loads are presented. Comparison with data for a Ni Superalloy showed life predictions could be 30X in excess of experimental values. This beam model also revealed that it is imperative that no bending moments be inadvertently applied during tensile creep testing. The creep-damage material model is extended to multidimensional situations. A refinement, whereby no damage accumulates in compression, is incorporated. A User-Material subroutine for this constitutive model has been formulated, and incorporated into the ABAQUS FEM package. Several verification examples are presented; one example is the creep-damage behaviour of a notched bar in tension. The value of reference stress techniques is discussed. Reference stress estimates for a centrifugally loaded bar, as well as for a cantilever under distributed loads, are presented. These could be useful in turbine blade design. Bibliography: pages 91-92.

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10

Almroth, Jonas, and Daniel Johansson. "Kapitalbindningsanalys vid Siemens Industrial Turbomachinery AB." Thesis, Linköping University, Department of Science and Technology, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-3758.

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Examensarbetet sammanfattar de mekanismer som binder kapital i den speciella miljö som råder i företagets gasturbintillverkning. De pågående verksamhetsutvecklande åtgärderna recenseras ur ett kapitalbindningsperspektiv och rekommendationer inför det fortsatta kapitalbindningsarbetet hos företaget presenteras. Rapporten visar även hur gängse mätmetoder och nyckeltal behöver anpassas för de långa ledtiderna och den höga grad av kundanpassning som företagets produkter kännetecknas av.

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11

Bringner, Martin. "Energianalys av Lavalverkstaden : Siemens Industrial Turbomachinery." Thesis, Linköping University, Energy Systems, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-52124.

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Det svenska elpriset har under de senaste åren stigit kraftigt vilket inneburit avsevärt högre energikostnader för många företag. Siemens Industrial Turbomachinery i Finspång är en av dessa och har under en längre tid sett hur energianvändningen ökar för varje år, framförallt på grund av en allt intensivare produktion. Företaget vill därför se över energianvändningen i verksamheten. En energikartläggning och åtgärdsförslag av den största produktionsbyggnaden på området, Lavalverkstaden, är ett steg i den riktningen.

Energikartläggningen har i grunden baserats på mätningar för att få en översiktlig bild över hur energianvändningen ser ut. Det sker genom att dela in energianvändningen i enhetsprocesser. Med mätningarna som stöd har också åtgärdsförslag identifierats och till viss del har det varit möjligt att kvantifiera besparingspotentialen. Investeringskostnaden är beräknad för de två största investeringarna, i övriga åtgärder är bara hänsyn tagen till besparingen.

Resultatet visar att det finns stora möjligheter att energieffektivisera verksamheten. Byte till ny allmänbelysning och ny tryckluftskompressor är de åtgärder som kräver störst investeringar men som också ger störst besparingar. LCC-analyser visar i båda fallen stor lönsamhet och investeringarna är betalda inom fyra respektive sex år. För övrigt föreslås bland annat konvertering, styrning av belysning och reducerad tomgång. Till följd av åtgärderna kan totalt 1,6 Mkr sparas genom reducering av

1 540 MWh el (-13 %)
733 MWh fjärrvärme (-15 %)
261 MWh fjärrkyla (-12 %)

Förutom de åtgärder som kan konkretiseras just nu finns en stor potential på lång sikt. Genom att fokusera mer på energianvändningen i det dagliga arbetet och ersätta energikrävande utrustning mot energieffektivare alternativ kan företagets energianvändning reduceras även framöver. Bland annat finns förslag i rapporten på vad som bör finnas med i inköpsrutiner för att främja inköp av energieffektiv utrustning.

In recent years the Swedish electricity price has risen sharply, which resulted in significantly higher energy costs for the companies. Siemens Industrial Turbomachinery in Finspång is one of those companies and for a long time they have seen how the energy usage is increasing every year, mainly due to an increased production. Therefore the company wants to investigate the energy usage and make an energy analysis of Laval workshop, the biggest production plant of the company.

The energy analysis is fundamentally based on measurements to get an overview of the energy usage of the plant. By dividing those in support and production processes, possibilities to energy efficiency measures have been identified and the savings potential quantified. The investment cost is quantified for the two largest investments, in other energy efficiency measures only the saving is taken into account.

The conclusion is that there are great possibilities to increase energy efficiency. A change of general illumination and a new air compressor calls for the greatest investments but also provides the greatest savings. LCC-analysis shows in both cases high profitability and investments are payed back within four and six years respectively. Moreover, a conversion, reduced lighting and idling losses is suggested. Due to the proposed actions, savings of totally 1.6 million SEK a year can be made by reducing

1537 MWh (-13 %) of electricity
733 MWh (-15 %) of district heating
261 MWh (-12 %) of district cooling

In addition to the energy efficiency measures that can be concretized there is a great potential to reduce the energy use also in longer term by focusing more of energy use in daily work. By adding routines when purchasing, energy efficient equipment can be promoted and energy use will be reduced even more.

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12

Mayorca, Maria Angelica. "Numerical Methods for Turbomachinery Aeromechanical Predictions." Doctoral thesis, KTH, Kraft- och värmeteknologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-48418.

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In both aviation and power generation, gas turbines are used as key components. An important driver of technological advance in gas turbines is the race towards environmentally friendly machines, decreasing the fuel burn, community noise and NOx emissions. Engine modifications that lead to propulsion efficiency improvements whilst maintaining minimum weight have led to having fewer stages and lower blade counts, reduced distance between blade rows, thinner and lighter components, highly three dimensional blade designs and the introduction of integrally bladed disks (blisks). These changes result in increasing challenges concerning the structural integrity of the engine. In particular for blisks, the absence of friction at the blade to disk connections decreases dramatically the damping sources, resulting in designs that rely mainly on aerodynamic damping. On the other hand, new open rotor concepts result in low blade-to-air mass ratios, increasing the influence of the surrounding flow on the vibration response. This work presents the development and validation of a numerical tool for aeromechanical analysis of turbomachinery (AROMA - Aeroelastic Reduced Order Modeling Analyses), here applied to an industrial transonic compressor blisk. The tool is based on the integration of results from external Computational Fluid Dynamics (CFD) and Finite Element (FE) solvers with mistuning considerations, having as final outputs the stability curve (flutter analysis) and the fatigue risk (forced response analysis). The first part of the study aims at tracking different uncertainties along the numerical aeromechanical prediction chain. The amplitude predictions at two inlet guide vane setups are compared with experimental tip timing data. The analysis considers aerodynamic damping and forcing from 3D unsteady Navier Stokes solvers. Furthermore, in-vacuo mistuning analyses using Reduced Order Modeling (ROM) are performed in order to determine the maximum amplitude magnification expected. Results show that the largest uncertainties are from the unsteady aerodynamics predictions, in which the aerodynamic damping and forcing estimations are most critical. On the other hand, the structural dynamic models seem to capture well the vibration response and mistuning effects. The second part of the study proposes a new method for aerodynamically coupled analysis: the Multimode Least Square (MLS) method. It is based on the generation of distributed aerodynamic matrices that can represent the aeroelastic behavior of different mode-families. The matrices are produced from blade motion unsteady forces at different mode-shapes fitted in terms of least square approximations. In this sense, tuned or mistuned interacting mode families can be represented. In order to reduce the domain size, a static condensation technique is implemented. This type of model permits forced response prediction including the effects of mistuning on both the aerodynamic damping as well as on the structural mode localization. A key feature of the model is that it opens up for considerations of responding mode-shapes different to the in-vacuo ones and allows aeroelastic predictions over a wide frequency range, suitable for new design concepts and parametric studies.
QC 20111125
Turbopower, AROMA

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13

Guerra, Mario. "Turbomachinery turbine blade vibratory stress prediction." Mémoire, École de technologie supérieure, 2006. http://espace.etsmtl.ca/535/1/GUERRA_Mario.pdf.

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Ce mémoire comportera quatre parties principales. Premièrement, une analyse des résultats expérimentaux de tests moteurs pour en retirer l'amortissement total des aubes ainsi que les contraintes vibratoires associées à chacune des résonances sera présentée. Deuxièmement, une méthode d'analyse par éléments finis avec des éléments de contact pour déterminer les fréquences naturelles et les modes sera présentée. Troisièmement, une analyse modale expérimentale en situation contrôlée sera effectuée sur une aube pour en déterminer la déformée modale ainsi que la valeur de l'amortissement pour chacun des modes. Ces résultats seront comparés avec les résultats obtenus lors des tests moteurs ainsi que les résultats obtenus par les modèles analytiques. Finalement, la méthode de prédiction des contraintes de la réponse forcée de l'aube ainsi que la comparaison entre les résultats analytiques et expérimentaux seront présentées.

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14

He, Li. "Unsteady flows around oscillating turbomachinery blades." Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385407.

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15

Naghshineh, Majid. "Structural investigation of high speed turbomachinery." Thesis, Imperial College London, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326668.

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16

Forhad, Md Moinul Islam. "Robustness analysis for turbomachinery stall flutter." Master's thesis, University of Central Florida, 2011. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4894.

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As compared with other robustness analysis tools, such as Hsubscript inf], the Mu analysis is less conservative and can handle both structured and unstructured perturbations. Finally, Genetic Algorithm is used as an optimization tool to find ideal parameters that will ensure best performance in terms of damping out flutter. Simulation results show that the procedure described in this thesis can be effective in studying the flutter stability margin and can be used to guide the gas turbine blade design.; Flutter is an aeroelastic instability phenomenon that can result either in serious damage or complete destruction of a gas turbine blade structure due to high cycle fatigue. Although 90% of potential high cycle fatigue occurrences are uncovered during engine development, the remaining 10% stand for one third of the total engine development costs. Field experience has shown that during the last decades as much as 46% of fighter aircrafts were not mission-capable in certain periods due to high cycle fatigue related mishaps. To assure a reliable and safe operation, potential for blade flutter must be eliminated from the turbomachinery stages. However, even the most computationally intensive higher order models of today are not able to predict flutter accurately. Moreover, there are uncertainties in the operational environment, and gas turbine parts degrade over time due to fouling, erosion and corrosion resulting in parametric uncertainties. Therefore, it is essential to design engines that are robust with respect to the possible uncertainties. In this thesis, the robustness of an axial compressor blade design is studied with respect to parametric uncertainties through the Mu analysis. The nominal flutter model is adopted from (9). This model was derived by matching a two dimensional incompressible flow field across the flexible rotor and the rigid stator. The aerodynamic load on the blade is derived via the control volume analysis. For use in the Mu analysis, first the model originally described by a set of partial differential equations is reduced to ordinary differential equations by the Fourier series based collocation method. After that, the nominal model is obtained by linearizing the achieved non-linear ordinary differential equations. The uncertainties coming from the modeling assumptions and imperfectly known parameters and coefficients are all modeled as parametric uncertainties through the Monte Carlo simulation.
ID: 030423207; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Thesis (M.S.)--University of Central Florida, 2011.; Includes bibliographical references (p. 44-47).
M.S.
Masters
Mechanical, Materials, and Aerospace Engineering
Engineering and Computer Science

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17

Ning, Wei. "Computation of unsteady flow in turbomachinery." Thesis, Durham University, 1998. http://etheses.dur.ac.uk/4819/.

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Unsteady flow analysis has been gradually introduced in turbomachinery design systems to improve machine performance and structural integrity. A project on computation of unsteady flows in turbomachinery has been carried out. A quasi 3-D time-linearized Euler/Navier-Stokes method has been developed for unsteady flows induced by the blade oscillation and unsteady incoming wakes, hi this method, the unsteady flow is decomposed into a steady flow plus a harmonically varying unsteady perturbation. The coefficients of the linear perturbation equation are formed from steady flow solutions. A pseudo-time is introduced to make both the steady flow equation and the linear unsteady perturbation equation time-independent. The 4-stage Runge-Kutta time-marching scheme is implemented for the temporal integration and a cell-vertex scheme is used for the spatial discretization. A 1-D/2-D nonreflecting boundary condition is applied to prevent spurious reflections of outgoing waves when solving the perturbation equations. The viscosity in the unsteady Navier- Stokes perturbation equation is frozen to its steady value. The present time-linearized Euler/Navier-Stokes method has been extensively validated against other well- developed linear methods, nonlinear time-marching methods and experimental data. Based upon the time-linearized method, a novel quasi 3-D nonlinear harmonic Euler/Navier-Stokes method has been developed. In this method, the unsteady flow is divided into a time-averaged flow plus an unsteady perturbation. Time-averaging produces extra nonlinear "unsteady stress" terras in the time-averaged equations and these extra terras are evaluated from unsteady perturbations. Unsteady perturbations are obtained by solving a first order harraonic perturbation equation, while the coefficients of the perturbation equation are forraed from time-averaged solutions. A strong coupling procedure is applied to solve the time-averaged equation and the unsteady perturbation equation simultaneously in a pseudo-time domain. An approximate approach is used to linearize the pressure sensors in artificial smoothing

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18

Hamakhan, Idres Azzat. "Design of high efficiency turbomachinery blades." Thesis, Queen Mary, University of London, 2010. http://qmro.qmul.ac.uk/xmlui/handle/123456789/618.

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19

Appukuttan, Ajith. "Probe measurement errors in turbomachinery flows." Thesis, University of Cambridge, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.613303.

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20

Jaffa, Nicholas Andrew. "Unsteady measurement techniques for turbomachinery flows." Thesis, University of Notre Dame, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3732212.

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Accurate unsteady measurements are required for studying the flows in high speed turbomachines, which rely on the interaction between rotating and stationary components. Using statistics of phase locked ensembles simplifies the problem, but accurate frequency response in the 10-100 kHz range significantly limits the applicable techniques. This research advances the state of the art for phase resolved measurement techniques using for high speed turbomachinery flows focusing on the following areas: development, validation, and uncertainty quantification. Four methods were developed and implemented: an unsteady total pressure probe, the multiple overheat hot-wire method, the slanted hot-wire method, and the phase peak yaw hot-wire method. These methods allow for the entire phase locked average flow field to be measured (temperature, pressure, and velocity components, swirl angle, etc.). No trusted reference measurement or representative canonical flow exists for comparison of the phase resolved quantities, making validation challenging. Five different validation exercises were performed to increase the confidence and explore the range of applicability. These exercises relied on checking for consistency with expected flow features, comparing independent measurements, and cross validation with CFD. The combined uncertainties for the measurements were quantified using uncertainty estimates from investigations into the elemental error sources. The frequency response uncertainty of constant temperature hot-wire system was investigated using a novel method of illuminating the wire with a laser pulse. The uncertainty analysis provided estimates for the uncertainty in the measurements as well as showing the sensitivity to various sources of error.

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21

Das, Kaushik. "Numerical Simulations of Icing in Turbomachinery." University of Cincinnati / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1147363332.

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22

GASTALDI, CHIARA. "Vibration control and mitigation in turbomachinery." Doctoral thesis, Politecnico di Torino, 2017. http://hdl.handle.net/11583/2677053.

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The thesis project is directly concerned with safety and reliability as it addresses the problem of High Cycle Fatigue (HCF) failure of turbine blades. Turbine blades can be found in engines used to power aircrafts and electrical generators. Statistics suggest that on average 2.5 HCF events occur on each new design engine. These failures happen suddenly, as resonant vibrations cause cracks which usually propagate very rapidly. Since it is often impossible to avoid the presence and growth of such resonant vibrations, designers frequently incorporate dry friction devices into turbine designs. Typical examples of friction dampers are shrouds, snubbers and underplatform dampers. Despite the continuous effort found in the literature in terms of modeling and optimization strategies, the lack of knowledge on the damping mechanism and on the parameters used to characterize it cause problems at all levels of the life cycle of bladed disks. The design process is uncertain, and therefore lengthy and costly because the knowledge of the dynamic behavior of the system has to be substituted with extensive experimental verifications. Furthermore, the imperfect knowledge of the real life expectancy of components prevents scheduling opportune periodic maintenance leading to potential safety hazard and logistical problems associated with unreliability. The focus of the dissertation is on under-platform dampers and their effect on bladed disks. All numerical models of friction-damped bladed arrays require information of contact parameters. The main goal is to face part of this knowledge limitation through a purposely developed experimental-numerical method. Direct measurements on dampers are used to estimate contact parameters to be used as input to a state-of-the-art numerical model. The numerical model, validated against independent experimental evidence, is proven to be predictive, thus paving the way to the creation of a reliable design and optimization tool.

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23

Heng, Yaguang. "Décrochage tournant dans un diffuseur lisse radial : Étude de stabilité et effet sur la performance." Thesis, Paris, ENSAM, 2017. http://www.theses.fr/2017ENAM0049/document.

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Résumé: Le comportement des turbomachines (pompes, compresseurs) fonctionnant à des conditions hors conception, et particulièrement aux débits partiels, est sujet à des phénomènes d'instabilité qui pourraient affecter leur performance et peuvent être dramatiques pour les machines ou leur environnement. Cette étude se concentre sur la décrochage tournant dans un diffuseur lisse radial. L'objectif est proposer un modèle théorique pour prédire rapidement les caractéristiques de décrochage tournant. Une étude expérimentale est effectuée en premier pour obtenir les caractéristiques de décrochage tournant dans un transparent diffuseur lisse d’une roué radiale. L'effet de décrochage tournant sur la performance du diffuseur est discuté basé sur les mesures de pression statique. Le résultat montre que décrochage tournant amélioré la récupération de la diffuseur pression, et les raisons sont proposes. Basé sur la configuration expérimentale, une analyse de stabilité linéaire qui est construit par l'équation de continuité, l'équation de la quantité de mouvement et les équations de vorticité, est propose. Les caractéristiques expérimentales de décrochage tournant: le nombre et la vitesse de propagation des cellules de décrochage tournant, sont calculés théoriquement. Le taux de croissance dans le modèle linéaire, est proposé pour déterminer la critique condition de décrochage tournant, et le dominant mode de décrochage tournant lorsque différents modes existent par intermittence. La théorique vitesse et pression fluctuations sont tracées pour décrire le débit du diffuseur à l'état de décrochage. Les capacités et les limites de la linéaire stabilité analyse sont conclues par la comparaison entre les résultats théoriques et expérimentaux. Ensuit, une non linéaire stabilité analyse est étendue pour considérer les non linéaires combinaisons qui sont négligées dans le modèle linéaire. L'objectif est donner des corrections (par termes non linéaires) aux résultats linéaires, les conclusions et les discussions sont faites à la fin
Abstract:The behavior of work-absorbing turbomachines (pumps, compressors) operating at off design conditions, and especially at partial flow rates, is subject to instability phenomena that could affect their performance and can be dramatic for the machines or their environment. This study is focused on the rotating stall in the vaneless diffuser, the objective is to propose a theoretical model to fast predict the characteristics of such an instability. An experimental study is performed first to obtain those characteristics of rotating stall in a transparent vaneless diffuser of a radial impeller. The effect of rotating stall on the diffuser performance is discussed based on the static pressure measurements. The result shows rotating stall improved the diffuser pressure recovery, and the reasons are proposed. Based on the experimental setup, a linear stability analysis which is constructed by the continuity equation, momentum equation and vorticity equations, is proposed. The experimental characteristics of rotating stall: number and propagation velocity of stall cells, are theoretical calculated. The growth rate in the linear model, is proposed to determine the critical stall condition, and the dominant stall mode when different stall modes exist intermittently. The theoretical velocity and pressure fluctuations are also plotted to show the diffuser flow at stall condition. The abilities and limits of the linear stability analysis are concluded through the comparisons between theoretical and experimental results. Based on the linear model, a nonlinear stability analysis is extended to consider the nonlinear combinations which are neglected in the linear model, the aim is to give corrections (from nonlinear terms) to the linear results of rotating stall, the conclusions and discussions are made at the end

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24

Pelton, Robert John. "One-Dimensional Radial Flow Turbomachinery Performance Modeling." Diss., CLICK HERE for online access, 2007. http://contentdm.lib.byu.edu/ETD/image/etd2192.pdf.

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25

Sever, Ibrahim Ata. "Experimental validation of turbomachinery blade vibration predictions." Thesis, Imperial College London, 2004. http://hdl.handle.net/10044/1/8393.

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26

Harvey, Simon Alexander. "The design optimisation of turbomachinery blade rows." Thesis, University of Cambridge, 2003. https://www.repository.cam.ac.uk/handle/1810/251866.

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27

Gostelow, J. P. "Publications in turbomachinery aerodynamics and related fields." Thesis, University of Liverpool, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.384347.

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28

Ahmadi, Majid. "Aerodynamic inverse design of transonic turbomachinery cascades." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0003/NQ40321.pdf.

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29

Burdyshaw, Chad Eric. "QUASI 3D MULTI-STAGE TURBOMACHINERY PRE-OPTIMIZER." MSSTATE, 2001. http://sun.library.msstate.edu/ETD-db/theses/available/etd-07052001-111807/.

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A pre-optimizer has been developed which modifies existing turbomachinery blades to create new geometries with improved selected aerodynamic coefficients calculated using a linear panel method. These blade rows can then be further refined using a Navier-Stokes method for evaluation. This pre-optimizer was developed in hopes of reducing the overall CPU time required for optimization when using only Navier-Stokes evaluations. The primary method chosen to effect this optimization is a parallel evolutionary algorithm. Variations of this method have been analyzed and compared for convergence and degree of improvement. Test cases involved both single and multiple row turbomachinery. For each case, both single and multiple criteria fitness evaluations were used.

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30

Ghenaiet, Adel. "Turbomachinery performance degradation due to erosion effect." Thesis, Cranfield University, 2001. http://hdl.handle.net/1826/3542.

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Erosion of gas turbines operating in sandy or dusty environments can result in serious damage to the engine components, particularly the compressor unit. This phenomenon is a result of the ingestion of the sand particles into the engine and their consequent abrasive impacts on the blade surfaces. In order to understand the mechanism of sand ingestion and the resulting performance degradation, a general methodology has been developed for predicting the trajectories of particles, the erosion rates and blade profile changes, with predictive capabilities for performance degradations within more general configurations of turbomachines. This methodology was applied to an axial fan with upstream guide vanes (contra whirl) and was supported by experimental results. The numerical models for calculating the particle trajectory are based on the Lagrangian tracking technique and the eddy lifetime concept. The turbulence effect is assumed to prevail as long as the particle eddy interaction time is less than the eddy lifetime, and the displacement of a particle relative to the eddy is less than the eddy length. The flow field was solved separately using the Navier-Stokes finite volume flow solver " TASCflow " commercially available from ASC. The governing equations of the particle motion are solved using the Runge-Kutta Fehlberg technique. The tracking of particles and their locations is based on a finite element interpolation method. The developed Fortran code for predicting particle trajectory and erosion due to particle impact accounts for different types of boundary conditions and handles different frames of reference. The fragmentation of particles after rebound was also implemented. The number of particles seeded upstream of the IGV blades can be determined either by a user defined concentration profile or by a measured concentration profile. Also, particles can be seeded separately in a group at a release position. In the present study, the concentration profile and the initial particle velocity and angle of particle spread were determined from a laser transit anemometer. Two types of particles were used, a narrow size bandwidth (150-300micron) quartz particle and MIL-E5007E quartz particle, both of which have a normal distribution. The global rate of erosion, the reduced mass of blades and the changes of the blade geometry were predicted and compared with experimental results at different concentration levels. The baseline axial fan characteristics were measured at different mass flow conditions at a constant speed of rotation. To assess the effects of erosion, the characteristic measurement was repeated after each step of sand ingestion. The predicted aerodynamic performance; adiabatic efficiency, pressure rise coefficient and stall margin before and after erosion degradation were also determined from a developed Fortran program, which is basically a mean line method that uses advanced correlations for aerodynamic losses. Prediction of the particle trajectories show that high numbers of impacts (and maximum erosion) occurred near leading edge and tip region, which were also borne out by locally injected sand tests. The global rate of erosion and the consequent changes of the blade geometry were also predicted and compared with experimental results. The erosion pattern at high concentration of MIL-E5007E sand particles depicts net loss of material over the leading edge and the tip corner. The tip clearance increased markedly with a rounding of blade leading edge, which is the main cause of the decrease in efficiency, pressure rise, and surge margin. A parametric study with turbulence and fragmentation effects show that both parameters can influence the erosion rate and blade geometry deterioration. The results of the aerodynamic performance simulation using mean line method, which includes an erosion fault model, show good agreement with experimental results.

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Khobeiz, Mohamed Hussien. "Numerical simulation of viscous incompressible turbomachinery flow." Thesis, University of Sheffield, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.338828.

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Birch, N. T. "Turbulence and transition modelling in turbomachinery flows." Thesis, Cranfield University, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.379491.

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Teo, Chiang Juay. "MEMS turbomachinery rotordynamics : modeling, design and testing." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/36180.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2006.
Includes bibliographical references (p. 347-350).
One of the major challenges encountered for the successful operation of high-power-density micro-devices lies in the stable operation of the bearings supporting the high-speed rotating machinery. This thesis presents the analysis, design, microfabrication, testing and operation of high speed micro-hydrostatic gas bearings for microturbomachinery in power-MEMS applications. A novel turbine driven microbearing test device for demonstrating repeatable high-speed gas bearing operation was designed, microfabricated and tested. The new microbearing test device incorporates numerous features, including a four plena journal bearing feed system enabling both isotropic and anisotropic journal bearing operation, labyrinth seals for reducing rotordynamic coupling, a redesigned turbine for satisfying power requirements, reinforced thrust bearing structural design, a novel rotor fabrication technology for achieving low radial imbalance and a symmetric feed system to avoid rotor sideloading arising from pressure or flow non-uniformities. A rigorous theory is presented to analyze the effects of compressibility in micro-flows (characterized by low Reynolds numbers and high Mach numbers) through hydrostatic thrust bearings for application to microturbomachines.
(cont.) Operating protocols for ensuring thrust bearing static stability have been established and successfully demonstrated on several micro-devices in the MIT Microengine Project. In addition, a simple and useful dynamic stability criterion has been identified: Dynamic instability occurs when the flow through both thrust bearings chokes. A-priori dynamic stability predictions were subsequently verified experimentally for the first time on a micro-turbocharger. A generalized Green's function approach has been successfully implemented for analyzing tilting effects and geometric non-uniformities in micro-hydrostatic gas thrust bearings. The effects of a non fully-developed circumferential flow in low length-to-diameter ratio (L/D << 1) micro-hydrostatic journal bearings are analyzed for the first time. Effects on journal bearing whirl stability and viscous power dissipation are quantified using a simple analytical model and CFD calculations. A dimensionless parameter characterizing the ratio of the flow-through time of the axial hydrostatic flow to the viscous diffusion time was identified to govern the evolution of the circumferential flow field. Singular behavior of the stability boundary or whirl-ratio occurs when the flow through time of the axial hydrostatic flow is approximately half the characteristic viscous diffusion time.
(cont.) Operating conditions for high speed, stable journal bearing operation can thus be ascertained. Experimental techniques and data reduction schemes facilitating the evaluation of key journal bearing rotordynamic information such as the stiffness, natural frequency and damping ratio, as well as the imbalance of the rotor have been successfully implemented. Imbalance-driven whirl response curves for providing an improved understanding of the rotordynamic behavior of micro-hydrostatic gas journal bearings have been obtained for the first time. Effects of journal bearing width and anisotropy are systematically investigated on the redesigned microbearing test device. For low levels of journal differential pressures DP, high whirl ratios ranging between 20 and 40 were achieved. These whirl-ratios were one order of magnitude higher than those encountered in macro-scale journal bearings. Almost all devices tested anisotropically at high values of DP achieved speeds in excess of 1 million rpm. The improvements in bearings and seals design, the high reliability of the novel microfabrication processes, and the repeatability and successful implementation of the operating protocols were vindicated.
(cont.) A first-of-a-kind controlled high speed operation up to 70% of the design speed was also demonstrated. This corresponds to a rotation rate of 1.7 million rpm, a rotor tip speed of 370 m/s and a DN number of 7 million mm-rpm. The technical feasibility of high-speed gas bearings required for achieving high power densities in MEMS-based micro-turbomachinery has thus been experimentally demonstrated.
by Chiang Juay Teo.
Ph.D.

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Chen, Gwo-Tung. "Vortical structures in turbomachinery tip clearance flows." Thesis, Massachusetts Institute of Technology, 1991. http://hdl.handle.net/1721.1/43153.

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Shrinivas, Gorur N. "Three-dimensional design methods for turbomachinery applications." Thesis, University of Oxford, 1996. http://ora.ox.ac.uk/objects/uuid:8ace58b5-e251-491e-9753-ae8b236d6c3b.

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This thesis studies the application of sensitivity analysis and optimization methods to the design of turbomachinery components. Basic design issues and a survey of current design trends are presented. The redesign of outlet guide vanes (OGV's) in an aircraft high bypass turbofan engine is attempted. The redesign is necessitated by the interaction of the pylon induced static pressure field with the OGV's and the fan, leading to reduced OGV efficiency and shortened fan life. The concept of cyclically varying camber is used to redesign the OGV row to achieve suppression of the downstream disturbance in the domain upstream of the OGV row. The redesign is performed using (a) a linear perturbation CFD analysis and (b) a minimisation of the pressure mismatch integral by using a Newton method. In method (a) the sensitivity of the upstream flow field to changes in blade geometry is acquired from the linear perturbation CFD analysis, while in method (b) it is calculated by perturbing the blade geometry and differencing the resulting flow fields. Method (a) leads to a reduction in the pylon induced pressure variation at the fan by more than 70% while method (b) achieves up to 86%. An OGV row with only 3 different blade shapes is designed using the above method and is found to suppress the pressure perturbation by more than 73%. Results from these calculations are presented and discussed. The quasi-Newton design method is also used to redesign a three dimensional OGV row and achieves considerable reduction of upstream pressure variation. A concluding discussion summarises the experiences and suggests possible avenues for further work.

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Read, Simon. "Transition to turbulence in a turbomachinery environment." Thesis, Cranfield University, 1997. http://dspace.lib.cranfield.ac.uk/handle/1826/10509.

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This thesis aims to contribute to the understanding of transitional flows in the blade boundary layers of axial compressors. Two experiments are described, the first examining in detail the transitional boundary layer on a simulated controlled-diffusion blade and the second surveying the mid-height flowfield in an embedded stage of a low-speed axial compressor. The velocity distribution on the simulated blade is identical to the Velocity distribution on the suction surface of the blades in the axial compressor. At 2 Reynolds numbers and 3 levels of freestream turbulence, a single hot wire was used to conduct a boundary layer survey on a simulated controlled-diffusion blade. Integral parameters of the boundary layers are explored to dene the length and nature of transition. At low Reynolds number there is a separated or near separated region at the leading edge which does not lead to turbulence. Transition covers a length of approximately 20% of the blade chord, starting between 20% and 30% chord. The position of transition is strongly influenced by the level of freestream turbulence. Most of the transition process occurs within the decelerating flow region which exists from 20% of the chord. At high Reynolds number, a leading edge separation bubble leads to transition within 2% of the blade chord. Abu-Ghannam & Shaws correlation for the start and length of transition was found to predict the start of transition well for attached flows, but could not be relied upon for separated flows. It is apparent that the correlation was not designed for the very strong Velocity gradients in the leading edge region, and probably not for separated flow. _ Three flow conditions in the axial compressor were used: design speed, peak efficiency, low Reynolds number at peak efficiency (the machine was slowed to one-quarter speed) and design speed near the stall. Using hot wires at mid-height, axial and circumferential velocity and turbulence information was obtained. Wakes and structure within wakes are visible in the turbulence and Reynolds stress distributions. The wakes of more than one upstream blade row are visible; the region where two wakes intersect gives some information about interaction between a stator blade Wake and a rotor blade boundary layer. Some information is available about the length scale 'distribution inside and outside wakes. Secondary flow in the axial-circumferential plane shows motion within wakes and a vortex in the near-stall flowfield, shed preferentially at one point in the blade-passing cycle.

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Pervier, Marie-Laure. "Mechanics of ice detachment applied to turbomachinery." Thesis, Cranfield University, 2012. http://dspace.lib.cranfield.ac.uk/handle/1826/11572.

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Flying in icing conditions is a real hazard for aircraft as they can undergo potential disastrous increase in drag, reduction in maximum lift which lead to an increase in fuel consumption. Additionally pitot tubes and other sensors can become blocked or their operation compromised. Ice shed from other parts of the aircraft can enter the engine and lead to blade damage. Whilst ice protection systems are comonly used on propellers, the potential benefit of applying them to a fan have not, as yet, been considered suffi cient to o set the cost and energy penalties of such system. As engines become larger, it is more diffi cult to contain ice and self-shedding becomes an increasing hazard for the nacelle and other parts downstream of the fan. The main objectives of the project were to determine the mechanical proper- ties of ice such as might form on an engine fan, in order to help Rolls-Royce in building a finite elements model able to simulate ice shedding from fan blades. Lots were written about ice however only little information about the mechanical properties of impact ice was available in the literature and the values which were, were generally not applicable in the case of aeroengine in icing conditions. According to the literature and from Rolls-Royce photos and films of ice shedding from fan blades, self-shedding mechanisms were ruled by adhesive shear strength and tensile strength. Therefore, the experimental part of the project consisted of measuring these two mechanical properties as well as the density, the sti ness and the grain size of ice grown on titanium substrate. Two test rigs were used to measure the mechanical properties: the \mode I" and the \shear" test rig. The mode I test rig was already available and was only modified in order to test more specimens during each run. This test al- lowed to measure the pressure needed to remove the ice from the substrate in a running icing tunnel. Using equations from the literature, fracture energy, fracture toughness and tensile strength were calculated. The influence of ambient total temperature, cloud liquid water content and tunnel wind speed were investigated. Tensile strength was found to be increasing as the total temperature is decreasing, decreasing as the LWC is increasing and going trough a maximum as the tunnel wind speed is increasing. Values obtained lied in the range from 0.6 to 1.5 J.m-2 (corresponding to between 2 and 10 MPa) which is, in general, higher than the ones reported by other authors. This difference can be explained by the fact that the mode I test was conducted in a running icing tunnel while the previous authors have conducted the mechanical test after the tunnel has been stopped. In parallel, finite element models have been developed and results similar to the experiments were obtained ...[cont.].

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Brown, Jeffrey M. "Reduced Order Modeling Methods for Turbomachinery Design." Wright State University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=wright1229962254.

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Lohner, Kevin Andrew 1974. "Microfabricated refractory ceramic structures for micro turbomachinery." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/9479.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1999.
Includes bibliographical references (p. 103-109).
The MIT Microengine Project was initiated in 1995 as a joint effort between the Gas Turbine Laboratory (GTL) and Microsystems Technology Laboratory (MTL) to develop a MEMS-based micro-gas turbine engine. The thermodynamic requirements of power-generating turbomachinery drive the design towards high rotational speeds and high temperatures. To achieve the specified performance requires materials with high specific strength and creep resistance at elevated temperatures. The thermal and mechanical properties of silicon carbide make it an attractive candidate for such an application. Silicon carbide as well as silicon-silicon carbide hybrid structures are being designed and fabricated utilizing chemical vapor deposition of relatively thick silicon carbide layers (10-100 [mu]m) over time multiplexed deep etched silicon molds. The silicon can be selectively dissolved away to yield high aspect ratio silicon carbide structures with features that are hundreds of microns tall. Positive mold, negative mold, and hybrid Si/SiC processing techniques appear to be feasible microfabrication routes with potential for increasing microengine performance. Research has been performed to characterize the capabilities of these processes. Specimens fabricated in the course of this research show very good conformality and step coverage with a fine (~0.1 [mu]m diameter) columnar microstructure. Surface roughness (Rq) of the films is on the order of 100 nm, becoming rougher with thicker deposition. Residual stress limits the achievable thickness, as the strain energy contained within the compressive film increases its susceptibility to cracking. Room temperature biaxial mechanical testing of CVD silicon carbide exhibits a reference strength of 724 MPa with a Weibull modulus, m =16.0. This thesis documents the design trades that led to the selection of CVD SiC as the primary candidate refractory material for the microengine, and the initial experiments performed to assess its suitability and guide future material and process development.
by Kevin Andrew Lohner.
S.M.

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Venturelli, Giovanni. "Development of numerical procedures for turbomachinery optimizaion." Doctoral thesis, Università degli studi di Padova, 2015. http://hdl.handle.net/11577/3424102.

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This Doctoral Thesis deals with high speed turbomachinery optimization and all those tools employed in the optimization process, mainly the optimization algorithm, the parameterization framework and the automatic CFD-based optimization loop. Optimization itself is not just a mean to improve the performance of a generic system, but can be a powerful instigator that helps gaining insight on the physic phenomena behind the observed improvements. As for the optimization engine, a novel surrogate-assisted (SA) genetic algorithm for multi-objective optimization problems, namely GeDEA-II-K, was developed. GeDEA-II-K is grounded on the cooperation between a genetic algorithm, namely GeDEA-II, and the Kriging methodology, with the aim at speeding up the optimization process by taking advantage of the surrogate model. The comparison over two- and three-objective test functions revealed the effectiveness of GeDEA-II-K approach. In order to carry out high speed turbomachinery optimizations, an automatic CFD-based optimization loop built around GeDEA-II-K was constructed. The loop was realized for a UNIX/Linux cluster environment in order to exploit the computational resources of parallel computing. Among the tools, a dedicated parameterization framework for 2D airfoils and 3D blades has been designed based on the displacement filed approach. The effectiveness of both the CFD-based automatic loop and the parameterization was verified on two real-life multi-objective optimization problems: the 2D shape optimization of a supersonic compressor cascade and the 3D shape optimization of the NASA Rotor 67. To better understand the outcomes of the optimization process, a wide section has been dedicated to supersonic flows and their behavior when forced to work throughout compressor cascades. The results obtained surely have demonstrated the effectiveness of the optimization approach, and even more have given deep insight on the physic of supersonic flows in the high speed turbomachinery applications that were studied.
“Sviluppo di procedure numeriche per l’ottimizzazione di turbomacchine” raccoglie la ricerca svolta dall’autore nel periodo di Dottorato che va dal 2010 al 2013. Il lavoro è nato con una duplice finalità: da una parte sviluppare un algoritmo per l’ottimizzazione multi obiettivo; dall’altra, accoppiare il motore di ottimizzazione con strumenti di analisi basati sulla fluidodinamica computazionale (CFD) per studiare casi di interesse nell’ambito del “high speed turbomachinery”. Gli algoritmi evolutivi hanno dimostrato alta affidabilità e robustezza nel raggiungimento del “Fronte di Pareto” (i.e., è la soluzione di un problema multi obiettivo), richiedendo però un numero di valutazioni delle funzioni obiettivo molto elevato, talvolta impraticabile dal punto di vista industriale. Infatti, quando la CFD è impiegata per valutare le funzioni obiettivo del sistema in esame, il costo computazionale può diventare il vero collo di bottiglia dell’intero processo. Una possibile soluzione viene fornita dai modelli surrogati, o metamodelli, cioè tecniche matematiche il cui scopo è quello di approssimare le funzioni obiettivo permettendo, di fatto, di diminuire le chiamate dirette alla CFD e di conseguenza anche il tempo totale del processo di ottimizzazione. Il vero dilemma è come affiancare gli algoritmi evoluti a uno o a più modelli surrogati, al fine di migliorare le prestazioni del motore di ottimizzazione. A oggi il problema non ha una soluzione univoca. La tesi è costituita da cinque capitoli. Il primo capitolo vuol essere di introduzione sia ai modelli surrogati visti nell'ottica dell’ottimizzazione, sia alle strategie di ottimizzazione che sono state applicate per migliorare i compressori transonici e le schiere supersoniche di compressori, che rappresentano i casi di interesse studiati in questa Tesi. Il secondo capitolo è dedicato al motore di ottimizzazione sviluppato dall’autore, denominato GeDEA-II-K. Il GeDEA-II-K nasce dall’unione del preesistente algoritmo genetico GeDEA-II e di un modello surrogato basato sul Kriging. Le prestazioni del nuovo algoritmo sono state testate su problemi matematici a due e a tre obiettivi ben noti in letteratura. Nel terzo capitolo è stato approfondito in grande dettaglio la fisica alla base delle schiere supersoniche, cercando di comprendere il legame profondo tra la geometria della schiera e il campo di moto che si viene a creare. Nel quarto e nel quinto capitolo è stato testato il loop automatico di ottimizzazione sviluppato dall’autore che comprende il motore di ottimizzazione, il tool di parametrizzazione della geometria, i modelli CFD, e tutti quegli elementi indispensabili per garantire robustezza ad una procedura automatica. Nello specifico è stata condotta l’ottimizzazione di una schiera supersonica e del compressore transonico NASA Rotor 67.

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Rajagopalan, Vinayaka Narayanan. "Diagnosing subsynchronous vibrations in turbomachinery - stable or unstable." Thesis, [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-1572.

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Kempe, Andreas. "Low coherence interferometry in turbomachinery and flow velocimetry /." Zürich : Laboratory of Fluiddynamics, Swiss Federal Institute of Technology (ETH) Zürich, 2007. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=16962.

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43

Gabrielsson, Petter. "Internal material transports at Siemens Industrial Turbomachinery AB." Thesis, Linköping University, Department of Science and Technology, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-15133.

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This report is the result of a master thesis work which has been carried out at Siemens Industrial Turbomachinery AB (SIT). The aim of the study has been to examine the possibilities of improving the internal material handling at SIT by making the flow of materials more efficient.

SIT develops, manufacture and sell steam and gas turbines to industrial customers all over the world. The site in Finspång consists of a number of workshops which are geographical spread across a fairly large area. This creates a need for material movements and transports that does not add any value to the final products being made.

To examine the possibilities of making the material handling at SIT more efficient, a description of the present situation and a mapping of the internal material flows have been made. With the mapping as a starting point, a proposal for how to improve the material flow is presented and analyzed regarding both quantitative and qualitative aspects.

The proposal, which is overarching and describes general effects rather than details, suggests that SIT relocate the core engine assembly department from the area called “Centrum” to the area called “Norrmalm” and locate the incoming goods area as close as possible to the place of the consumption of the material.

The analysis of the mapping shows that there is 180 kilometers of internal transports at SIT every week. In this distance, transport between different departments and different working stations in the same building, are not included. The need for transports exists mainly because of the fact that SIT has its incoming goods area located at Norrmalm, approximately 2.2 kilometers away from its warehouse building and by implementing the proposal given in this work, the weekly transport distance will decrease by 60 percent. Apart from the decrease in distance, the change will also make it possible to simplify the goods receiving process.

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Sadri, Malek Arsalan. "Numerical modelling of rotor/stator interactions in turbomachinery." Thesis, Imperial College London, 1997. http://hdl.handle.net/10044/1/7828.

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Schulte, Volker Benno. "Unsteady separated boundary layers in axial-flow turbomachinery." Thesis, University of Cambridge, 1995. https://www.repository.cam.ac.uk/handle/1810/252035.

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Wang, Xiao. "A preconditioned algorithm for turbomachinery viscous flow simulation." Diss., Mississippi State : Mississippi State University, 2005. http://sun.library.msstate.edu/ETD-db/ETD-browse/browse.

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Addison, John Stephen. "Wake-boundary layer interaction in axial flow turbomachinery." Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357704.

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Dahlquist, Henrik, and Mattias Ahlbert. "Return process Development at Siemens Industrial Turbomachinery AB." Thesis, Linköpings universitet, Logistik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-107018.

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Siemens Industrial Turbomachinery AB (SIT) manufactures gas turbines, conducts service and develop gas and steam gas turbines. The organization is located in Finspång and in Trollhättan with customers positioned all over the world. During later years the service operation has grown in volume significantly, and at the moment the organization returns number of parts for repair and recondition every year. During maintenance of a Customer turbine SIT uses both tools and instruments that when the maintenance is completed are returned to SIT in Finspång. The master thesis has studied the return processes for Siemens Industrial Turbomachinery AB for goods from the Customer site to Siemens Industrial Turbomachinery in Finspång and Trollhättan. The return processes can be divided into three main types: Planned Maintenance, Unplanned Maintenance and Tools and Instruments. The return processes and their adjacent processes have been mapped up in order to receive a picture over the present situation. The study has also summarized the demands from the processes before, during and after the return process. From the summarized demands, 26 actions have been formed that are directed at the return process. The actions have been prioritized and discussed during two seminars with personal with knowledge about the return process from different departments at Siemens. The prioritization and the authors’ own knowledge about the return process have resulted in suggestions for how Siemens Industrial Turbomachinery shall focus their work of improvement. The suggestions have been divided up into three steps so Siemens shall focus on the right action in the right order during the work of improvement. The actions include better communication, a reduced variation, correct hand over between processes and sub processes, change in work routines and an idea regarding necessary information for the process to be able to improve. One of the most important areas is that Siemens need to improve the basic data to be able to manage the returns when the maintenance of the customer turbine is planned. Siemens also needs to be able to carry out information regarding the return to the personal at customer site in a better way. The study has also examined how an internal measurement system would improve the return process. Of 22 measure points the study has suggested 6 measure points to be implemented in the return process that would help Siemens to better control their return process, make it easier to improve and to be able to make conclusions regarding future changes.
Siemens Industrial Turbomachinery AB (SIT) tillverkar gasturbiner och bedriver service av både gas och ångturbiner. Verksamheten har man belägen i Finspång och Trollhättan och kunderna finns belägna i hela världen. Under senare år har Siemens Industrial Turbomachinery AB serviceverksamhet vuxit kraftigt och i dag returnerar företaget en stor mängd delar för reparation och rekonditionering. Vid ett underhåll på kundens turbin används både verktyg och instrument som hyrs ut till underhåll över hela värden och när underhållet är klart ska de returneras till Siemens Industrial Turbomachinery AB i Finspång. Examensarbetet har studerat Siemens Industrial Turbomachinery ABs returprocesser för gods från kundens plats till Siemens Industrial Turbomachinery ABs i Finspång och Trollhättan. Returprocesserna kan delas in i tre huvud typer: Planerade delar, Oplanerade delar och Verktyg och Instrument. Returprocesserna och dess angränsade processer har kartlagts för att få en bild av nuläget, arbetet har även sammanställt kraven utifrån processerna före, under och efter returprocessen. Utifrån kravbilden har 26 åtgärder tagits fram som berör returprocesserna. Åtgärderna har prioriterats och diskuterats på två seminarier med Siemens personal från flera olika avdelningar som hanterar returer. Prioriteringen samt författarnas egen förståelse för processerna har utmynnat i ett förslag till hur Siemens ska gå till väga för att förbättra returprocesserna. Förslagen har då delats in i tre steg för att Siemens ska kunna fokusera på rätt sak i rätt ordning under förändringsarbetets gång. Åtgärderna behandlar bättre kommunikation, minskad variation i utfallet av processerna, korrekta överlämningar mellan processer och delprocesser, förändringar i arbetsrutiner och vilken information som krävs för att processerna ska fungera bättre. Ett av de viktigaste områdena är att Siemens måste förbättra underlaget för returerna när de planerar ett underhåll för kundens turbin. Siemens måste även bli bättre att föra ut information om returen till deras personal på plats hos kund. Studien har även undersökt hur ett internt mätsystem skulle förbättra processen. Av 22 mätpunkter har studien visat att 6 mätpunkter är intressanta för returprocesserna, de skulle hjälpa Siemens att skaffa kontroll på processen, styra mot förbättringar och kunna dra slutsatser om framtida förändringar.

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MacPherson, William Neil. "Fibre optic sensors for applications in turbomachinery research." Thesis, Heriot-Watt University, 1999. http://hdl.handle.net/10399/585.

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Tiow, Wee Teck. "Inverse design of turbomachinery blades in rotational flow." Thesis, University College London (University of London), 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325463.

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Dissertations / Theses on the topic 'Turbomachinery'

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