To see the other types of publications on this topic, follow the link: Turbomachine design.
Dissertations / Theses on the topic 'Turbomachine design'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Turbomachine design.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Zangeneh-Kazemi, Mehrdad. "Three-dimensional design of radial-inflow turbines." Thesis, University of Cambridge, 1989. https://www.repository.cam.ac.uk/handle/1810/250944.
Full textAbstract:
The main part of this dissertation is concerned with the development of a fully three dimensional compressible inverse design method, suitable for the design of radial-inflow turbines and other turbomachines with arbitrary meridional geometry. The basic idea of the method is to represent the action of the blades by sheets of vorticity whose strength is determined from prescribed distribution of rVθ (or circulation 2πrVθ). The flow is assumed subsonic and inviscid and the blades are assumed to have negligible thickness. But the blade blockage effects are approximately accounted for by using a mean streamsurface thickness parameter in the continuity equation. As a first approach, the pitchwise variation of density was neglected and the problem was solved by using an approximate form of the continuity equation. Simple expressions were derived for the terms neglected in the approximate continuity equation. The problem was also solved by using the exact form of the continuity equation and the results of the approximate and exact methods were compared for a number of test cases. The comparison showed that the approximate method can compute the blade shape accurately. A small high (subsonic) speed radial-inflow turbine was designed by the new method. In order to assess the accuracy of the method, the flow through the designed impeller was computed by three dimensional inviscid and viscous flow analysis programs and good correlation was obtained between the computed and specified rVθ distributions. The designed impeller was manufactured and its performance was measured and compared to three other baseline impellers, one conventional and two experimental. The new impeller performed substantially better than all the baseline turbines and showed a 5.5% improvement over the conventional impeller. However, only 2.5% of this improvement was attributed to the aerodynamically superior blade shape designed by the new method. An appreciable improvement in efficiency was also observed at off-design conditions. Finally, the presence of a, generally observed, high loss region near the shroud at exit of radial-inflow turbines was investigated and it was found that secondary flow is the basic mechanism behind this phenomenon.
2
Ragula, Vivian Vineeth Raj. "Streamline based Analysis and Design Technique for Turbomachines." University of Cincinnati / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1304022216.
Full text
3
Ji, Min. "Fully three-dimensional and viscous semi-inverse method for axial/radial turbomachine blade design." Related electronic resource: Current Research at SU : database of SU dissertations, recent titles available full text, 2008. http://wwwlib.umi.com/cr/syr/main.
Full text
4
Cai, Jun. "Diffuseur à aspiration pariétale avec application aux turbines à vapeur." Châtenay-Malabry, Ecole centrale de Paris, 1987. http://www.theses.fr/1987ECAP0035.
Full text
5
Chaves-Jacob, Julien. "Développement d'une méthodologie de réduction des défauts géométriques : application à l'usinage 5-axes de composants de turbomachine." Phd thesis, Paris, ENSAM, 2009. http://pastel.archives-ouvertes.fr/pastel-00005522.
Full textAbstract:
Ces travaux contribuent à l'amélioration de la fabrication de pièces complexes de turbomachine. Elles sont principalement composées de veines fluides souvent délimitées par des pales, dont la fonction première est de transférer de l'énergie entre un fluide et une partie mécanique. Dans ce cas précis, la géométrie de ces pièces est essentielle pour obtenir un bon rendement du mécanisme. Cependant, lors de l'usinage, les flexions des pales et/ou de l'outil ainsi que les interférences locales occasionnent des défauts géométriques pouvant nuire à l'efficacité du système. Dans le but de résoudre cette problématique, une approche globale est utilisée dans ce mémoire. Elle débute par l'étude de la conception de ces pièces, en introduisant des concepts de Design For Manufacturing, utilisables grâce à la proposition d'indicateurs de fabricabilité par usinage 5-axes de pièces de turbomachine. Cette démarche permet donc de garantir que les pièces conçues sont économiquement réalisables. Les travaux ont continué avec la mise en place d'une méthodologie d'aide au choix de la meilleure stratégie d'usinage basée sur des critères de respect des besoins fonctionnels de la pièce et des critères économiques. La seconde partie de ce mémoire est consacrée à l'étude d'une approche novatrice permettant la réduction des interférences locales lors de l'usinage par le flanc de surfaces non développables. Cette méthode, baptisée Computation of Adapted Tool Shape, optimise la forme de l'outil, pour une trajectoire et une surface données, afin d'obtenir un meilleur respect des besoins fonctionnels de la pièce. La dernière partie de ces travaux définit le domaine d'application de cette nouvelle méthode par sa mise en oeuvre sur des études de cas académiques et industriels.
6
Patel, Karnal. "Design and development of a pulsatile axial flow blood pump as a left ventricular assist device." Thesis, Brunel University, 2012. http://bura.brunel.ac.uk/handle/2438/11085.
Full textAbstract:
Each year all over the world, Millions of patients from infants to adults are diagnosed with heart failure. A limited number of donor hearts available for these patients results in a tremendous demand of mechanical circulatory support (MCS) system, either in the form of total artificial heart (TAH) or a ventricular assist device (VAD). Physiologically MCS are expected to provide heart; a time to rest and potential recovery by unloading the ventricle, while maintaining the adequate peripheral as well as coronary circulation. Existing ventricular assist devices (VAD) have employed either displacement type pulsatile flow pumping systems or continuous flow type centrifugal/rotodynamic pumps systems. Displacement type devices produce a pulsatile outflow, which has significant benefits on vital organ function and end organ recovery. Continuous flow devices are small and can be placed within body using minimal invasive procedures, in addition they reduces infection as well as mechanical failure related complications. Despite availability of success stories for both types of pumping systems, the selection of the either of them is an ongoing debate. This thesis aims to merge the advantages of displacement pumps (pulsatile flow) and axial-flow pumps (continuous flow) into a novel left vertical assist device (LVAD), by designing a novel minimal invasive, miniature axial-flow pump producing pulsating outflow for the patients having early heart failure and myocardial infarction as a Bridge-To-Recovery (BTR) or Bridge-To-Decision (BTD) device. The design of VAD, the experimental setup and dedicated control system were developed for the in vitro evaluation of pulsatile flow. Computational fluid dynamics (CFD) had been employed for the detail investigation of pulsatile flow. In addition, CFD was also applied to optimize the pulse generation for low haemolysis levels. Outcome of the study produces comprehensive understanding for the generation of pulsatile flow using an axial flow pump. Further, it provides the means of generating a controlled pulse that can regulate flow rate for varying heart rate within low haemolysis levels.
7
Boukider, Akli. "Conception des pompes centrifuges assistee par ordinateur : dimensionnement et trace, optimisation du profil meridien." Paris, ENSAM, 1988. http://www.theses.fr/1988ENAM0001.
Full text
8
Yoo, Hanyung. "A computational package to aid the design and to evaluate centrifugal turbopumps /." Online version of thesis, 1995. http://hdl.handle.net/1850/12289.
Full text
9
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.
Full text
10
Borges, J. E. "Three-dimensional design of turbomachinery." Thesis, University of Cambridge, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.384285.
Full text
11
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.
Full text
12
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.
Full textAbstract:
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.
13
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.
Full text
14
Teo, Chiang Juay. "MEMS turbomachinery rotordynamics : modeling, design and testing." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/36180.
Full textAbstract:
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2006.<br>Includes bibliographical references (p. 347-350).<br>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.<br>(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.<br>(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.<br>(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.<br>by Chiang Juay Teo.<br>Ph.D.
15
Brown, Jeffrey M. "Reduced Order Modeling Methods for Turbomachinery Design." Wright State University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=wright1229962254.
Full text
16
Harvey, Simon Alexander. "The design optimisation of turbomachinery blade rows." Thesis, University of Cambridge, 2003. https://www.repository.cam.ac.uk/handle/1810/251866.
Full text
17
DiPietro, Anthony Louis. "Design and experimental evaluation of a dynamic thermal distortion generator for turbomachinery research." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-09292009-020206/.
Full text
18
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.
Full text
19
Tsay, W. C. "The analysis and design methods for turbomachinery flows." Thesis, Cranfield University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233928.
Full text
20
Thiagarajan, Manoharan. "A Design Study of Single-Rotor Turbomachinery Cycles." Thesis, Virginia Tech, 2004. http://hdl.handle.net/10919/10076.
Full textAbstract:
Gas turbine engines provide thrust for aircraft engines and supply shaft power for various applications. They consist of three main components. That is, a compressor followed by a combustion chamber (burner) and a turbine. Both turbine and compressor components are either axial or centrifugal (radial) in design. The combustion chamber is stationary on the engine casing. The type of engine that is of interest here is the gas turbine auxiliary power unit (APU). A typical APU has a centrifugal compressor, burner and an axial turbine. APUs generate mechanical shaft power to drive equipments such as small generators and hydraulic pumps. In airplanes, they provide cabin pressurization and ventilation. They can also supply electrical power to certain airplane systems such as navigation. In comparison to thrust engines, APUs are usually much smaller in design.
The purpose of this research was to investigate the possibility of combining the three components of an APU into a single centrifugal rotor. To do this, a set of equations were chosen that would describe the new turbomachinery cycle. They either were provided or derived using quasi-one-dimensional compressible flow equations. A MathCAD program developed for the analysis obtained best design points for various cases with the help of an optimizer called Model Center. These results were then compared to current machine specifications (gas turbine engine, gasoline and diesel generators). The result of interest was maximum specific power takeoff. The results showed high specific powers in the event there was no restriction to the material and did not exhaust at atmospheric pressure. This caused the rotor to become very large and have a disk thickness that was unrealistic. With the restrictions fully in place, they severely limited the performance of the rotor. Sample rotor shapes showed all of them to have unusual designs. They had a combination of unreasonable blade height variations and very large disk thicknesses. Indications from this study showed that the single radial rotor turbomachinery design might not be a good idea. Recommendations for continuation of research include secondary flow consideration, blade height constraints and extending the flow geometry to include the axial direction.<br>Master of Science
21
Gutzwiller, David. "Automated Design, Analysis, and Optimization of Turbomachinery Disks." University of Cincinnati / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1258579409.
Full text
22
Wissinger, Gordon J. "Computational analysis of space transfer vehicle engine turbopump diffuser design for deep-throttling : by Gordon J. Wissinger /." Online version of thesis, 1991. http://hdl.handle.net/1850/11001.
Full text
23
Albusaidi, Waleed. "Techno-economic assessment of radial turbomachinery in process gas applications." Thesis, Cranfield University, 2016. http://dspace.lib.cranfield.ac.uk/handle/1826/9872.
Full textAbstract:
This research aims to assess the causes of inefficient and unstable operation of centrifugal compressors and turboexpanders in process gas applications in order to provide a solution for performance restoration and enhancement. It encompasses thermodynamic and flow evaluations to examine the efficiency and operating range improvement options of new units. Besides, this work is complemented by a technoeconomic analysis to provide a rounded outcome from these studies. In order to achieve the desired objectives, a novel integrated approach has been developed to assess the design and performance of multi-stage centrifugal compressors. The proposed systematic methodology involves five basic elements including evaluation of compressor selection, compressor sizing and casing structure, performance prediction at the design and off-design conditions, modelling of efficiency and head deterioration causes; and stage design evaluation. This will contribute towards evaluating the geometrical parameters of the new units’ designs at the early preliminary design phase, and thus, will be useful to identify the options for efficiency and operating range enhancements. For installed units, this approach can be implemented to assess the cause of inefficient and unstable operation by assessing the available operation data. A method was developed to predict the performance curve of multi-stage centrifugal compressor based on a stage stacking technique. This approach considers the advantages of Lüdtke and Casey-Robinson methods with an incorporation of a methodology for compressor selection and sizing to generate more accurate results. To emphasize the validity of the developed model, it has been evaluated for both low and high flow coefficient applications. The obtained results show a significant improvement in the estimated efficiency, pressure ratio, shaft power and operating range as compared with the existing methods. The centrifugal compressor is designed to run under various operating conditions and different gas compositions with the primary objective of high efficiency and reliability. Therefore, a new iterative method has been developed to predict the equivalent compressor performance at off-design conditions. This technique uses the performance parameters at design conditions as a reference point to derive the corresponding performance characteristics at numerous suction conditions with less dependency on the geometrical features. Through a case study on a gas transport centrifugal compressor, it was found that the developed approach can be applied for design evaluation on the expected variation of working conditions, and for the operation diagnosis of installed units as well. Furthermore, a parametric study has been conducted to investigate the effect of gas properties on the stage efficiency, surge margin, and compressor structure. The obtained results support the need for considering the gas properties variation when the off-design performance is derived. To evaluate the impact of internal blockage on the performance parameters, this study proposed an approach to model the effect of non-reactive deposits, which has been qualified using four operation cases and the obtained results are compared with the internal inspection findings from the stage overhauling process. This also covers the influential aspects of flow blockage on the technical and economic values. Since the main challenge here is to analyze the process gas composition in real time, the influences of the non-reactive deposits have been compared with the effect of the unanticipated gas composition change. Subsequently, it has turned out that the pressureratio parameter is not enough to assess the possibility of flow blockage and unexpected gas properties change. Moreover, it was observed that the stage discharge pressure was more sensitive to the fouled aftercooler comparing with suction and internal blockage. However, the effect of contaminated aftercooler on the surge point and discharge pressure and temperature of the upstream stage was found greater than its impact on the shaft power. Thus, a substantial surge margin reduction was detected when the first stage was operating with a fouled aftercooler comparing with the measured reduction as a result of unanticipated gas properties change. Furthermore, a larger pressure ratio drop was measured in the case of liquid carryover which revealed a more significant impact of the two phases densities difference comparing with the gas volume fraction (GVF) effect. The possibility of hydrate formation has been assessed using hydrate formation temperature (HFT) criteria. Additionally, this research highlights a number of challenges facing the selection of typical centrifugal stage design by assessing the contribution of design characteristics on the operating efficiency and stable flow range. Besides, an empirical-based-model was established to select the optimum impeller and diffuser configurations in order to make a compromise decision based on technical and economic perspective. It was concluded that there is no absolute answer to the question of optimum rotor and stator configuration. The preliminary aerothermodynamic evaluation exposed that the selection of the optimum impeller structure is governed by several variables: stage efficiency, pressure loss coefficient, manufacturing cost, required power cost, resonance frequency and stable operating range. Hence, an evaluation is required to compromise between these parameters to ensure better performance. Furthermore, it was argued throughout this study that the decision-making process of the typical stage geometrical features has to be based upon the long-term economic performance optimization. Thus, for higher long-term economic performance, it is not sufficient to select the characteristics of the impeller and diffuser geometry based on the low manufacturing cost or efficiency improvement criterion only. For turboexpanders, a simple and low cost tool has been developed to determine the optimum turboexpander characteristics by analysing the generated design alternatives. This approach was used in designing a turboexpander for hydrocarbon liquefaction process. Moreover, since the turboexpanders are expected to run continuously at severe gas conditions, the performance of the selected turboexpander was evaluated at different inlet flow rates and gas temperatures. It has turned out that designing a turboexpander with the maximum isentropic efficiency is not always possible due to the limitations of the aerodynamic parameters for each component. Therefore, it is necessary to assess the stage geometrical features prior the construction process to compromise between the high capital cost and the high energetic efficiency.
24
Raharjo, R. Firson Joko. "Two-dimensional inverse design and optimization of turbomachinery blades." Thesis, University College London (University of London), 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.406622.
Full text
25
Chen, Kuo-Shen 1966. "Materials characterization and structural design of ceramic micro turbomachinery." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/9396.
Full text
26
MA, XIANG. "NUMERICAL SOLUTIONS FOR DIRECT AND INDIRECT (DESIGN) TURBOMACHINERY PROBLEMS." University of Cincinnati / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1146077765.
Full text
27
Benamara, Tariq. "Full-field multi-fidelity surrogate models for optimal design of turbomachines." Thesis, Compiègne, 2017. http://www.theses.fr/2017COMP2368.
Full textAbstract:
L’optimisation des différents composants d’une turbomachine reste encore un sujet épineux, malgré les récentes avancées théoriques, expérimentales ou informatiques. Cette thèse propose et investigue des techniques d’optimisation assistées par méta-modèles vectoriels multi-fidélité basés sur la Décomposition aux Valeurs Propres (POD). Le couplage de la POD à des techniques de modélisation multifidélité permet de suivre l’évolution des structures dominantes de l’écoulement en réponse à des déformations géométriques. Deux méthodes d’optimisation multi-fidélité basées sur la POD sont ici proposées. La première consiste en une stratégie d’enrichissement adaptée aux modèles multi-fidelité par Gappy-POD (GPOD). Celle-ci vise surtout des problèmes associés à des simulations basse-fidélité à coût de restitution négligeable, ce qui la rend difficilement utilisable pour la conception aérodynamique de turbomachines. Elle est néanmoins validée sur une étude du domaine de vol d’une aile 2D issue de la littérature. La seconde méthodologie est basée sur une extension multi-fidèle des modèles par POD Non-Intrusive (NIPOD). Cette extension naît de la ré-interprétation du concept de POD Contrainte (CPOD) et permet l’enrichissement de l’espace réduit par ajout important d’information basse-fidélité approximative. En seconde partie de cette thèse, un cas de validation est introduit pour valider les méthodologies d’optimisation vectorielle multi-fidélité. Cet exemple présente des caractéristiques représentatives des problèmes d’optimisation de turbomachines. La capacité de généralisation des méta-modèles par NIPOD multifidélité proposés est comparée, aussi bien sur cas analytique qu’industriel, à des techniques de méta-modélisation issues de la littérature. Enfin, nous utilisons la méthode développée au cours de cette thèse pour l’optimisation d’un étage et demi d’un compresseur basse-pression et comparons les résultats obtenus à des approches à l’état de l’art<br>Optimizing turbomachinery components stands as a real challenge despite recent advances in theoretical, experimental and High-Performance Computing (HPC) domains. This thesis introduces and validates optimization techniques assisted by full-field Multi-Fidelity Surrogate Models (MFSMs) based on Proper Orthogonal Decomposition (POD). The combination of POD and Multi-Fidelity Modeling (MFM) techniques allows to capture the evolution of dominant flow features with geometry modifications. Two POD based multi-fidelity optimization methods are proposed. Thefirst one consists in an enrichment strategy dedicated to Gappy-POD (GPOD)models. It is more suitable for instantaneous low-fidelity computations whichmakes it hardly tractable for aerodynamic design of turbomachines. This methodis demonstrated on the flight domain study of a 2D airfoil from the literature. The second methodology is based on a multi-fidelity extension to Non-IntrusivePOD (NIPOD) models. This extension starts with a re-interpretation of theConstrained POD (CPOD) concept and allows to enrich the reduced spacedefinition with abondant, albeit inaccurate, low-fidelity information. In the second part of the thesis, a benchmark test case is introduced to test fullfield multi-fidelity optimization methodologies on an example presenting featuresrepresentative of turbomachinery problems. The predictability of the proposedMulti-Fidelity NIPOD (MFNIPOD) surrogate models is compared to classical surrogates from the literature on both analytical and industrial-scale applications. Finally, we employ the proposed tool to the shape optimization of a 1.5-stage boosterand we compare the obtained results with standard state of the art approaches
28
Jouini, Dhafer Ben Mahmoud Carleton University Dissertation Engineering Mechanical and Aerospace. "Experimental investigation of two transonic linear turbine cascades at off-design conditions." Ottawa, 2000.
Find full text
29
Jones, James A. "A multidisciplinary algorithm for the 3-D design optimization of transonic axial compressor blades." Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2002. http://library.nps.navy.mil/uhtbin/hyperion-image/02Jun%5FJones%5FJames.pdf.
Full textAbstract:
Thesis (Ph. D. in Aeronautics and Astronautics)--Naval Postgraduate School, June 2002.<br>Dissertation supervisor: Raymond P. Shreeve. Includes bibliographical references (p. 157-161). Also available online.
30
Wang, Dingxi. "Turbomachinery aerodynamic and aeromechanic design optimization using the adjoint method." Thesis, Durham University, 2008. http://etheses.dur.ac.uk/2057/.
Full textAbstract:
The thesis documents the investigation of the application of the adjoint method to turbomachinery blading design optimization, with emphasis on blading aerodynamic design optimization in a multi-bladerow environment and concurrent blading aerodynamic and aeromechanic design optimization for a single bladerow. Based on the nonlinear flow equations, a steady adjoint system has been developed using the continuous adjoint approach. The capability of the conventional adjoint system has been augmented by the introduction of an adjoint mixing-plane treatment. This treatment is a counterpart of the flow mixing-plane treatment, enabling the steady adjoint equations to be solved in multi-bladerow computational domains. This allows turbomachinery blades to be optimised to enhance their aerodynamic performance in a multi-bladerow environment with matching between adjacent bladerows dealt with in a timely manner. The Nonlinear Harmonic Phase Solution method, a neat frequency domain method catered specifically for turbomachinery aeromechanics prediction, has been chosen to integrate with the adjoint method to calculate objective function sensitivities efficiently for concurrent aeromechanic and aerodynamic design optimization for single row turbomachinery blades. The Nonlinear Harmonic Phase Solution method, unlike the time-linearized methods, solves the unsteady flow equations at two or three carefully selected phases of a period of unsteadiness. This approach not only can conveniently turn a steady flow solver to one solving the unsteady flow equations efficiently, but also provides a good basis on which the corresponding adjoint system can be formulated and solved in a similar manner by extending a steady adjoint system. In order to resolve the issue of having a good blading performance over a whole operating range at a given operation speed, a multi-operating-point design optimization is implemented by formulating an objective function of a weighted sum of performance at more than one operating point
31
Mehra, Amitav. "Computational investigation and design of low Reynolds number micro-turbomachinery." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/10516.
Full text
32
Powers, Laura M. "Computer-aided design of axial-flow fans." Thesis, Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/91059.
Full textAbstract:
This thesis examines the application of computer-aided design techniques to the field of turbomachinery. Specifically, the process of designing low- to medium-speed, axial-flow fans and blowers is discussed, and a Fortran program called FANJD is introduced. The first purpose of F AN3D is to perform the aerodynamic and mechanical calculations needed to establish the basic geometry of an axial-flow fan blade. Next, geometric modeling techniques are used to model the curves and surfaces of the blade, thereby completing the geometric description of the blade. Finally, FAN3D uses the CADCD component of the CADAM (CADAM, Inc.) Geometry Interface to automatically enter the three-dimensional blade model in the CADAM database.<br>M.S.
33
Fowler, Andrew. "A new advanced turbine-stage test facility : the concept, design, construction and commissioning." Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386786.
Full text
34
Kurtulus, Berkin. "Development of a Tool for Inverse Aerodynamic Design and Optimisation of Turbomachinery Aerofoils." Thesis, KTH, Flygdynamik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-293353.
Full textAbstract:
The automation of airfoil design process is an ongoing effort within the field of turbo-machinery design, with significant focus on developing new reliable and consistent methods that can meet the needs of the engineers. A wide variety of approaches has been in use for inverse airfoil design process which benefit from theoretical inverse design, statistical methods, empirical discoveries and many other ways to solve the design problem. This thesis work also develops a tool in Python to be used in airfoil aerodynamic design process that is simple, fast and accurate enough for initial design of turbo-machinery blades with focus on turbine airfoils used for operation in aircraft engines. To convey the decision-making process during development a simplified case is presented. The underlying considerations are discussed. Other available methods in the literature used for similar problems, are also evaluated and compared to demonstrate the advantages and limitations of the methods used within the tool. The inverse design problem is formulated as a multi-objective optimization problem to handle various different objectives that are relevant for aerodynamic design of turbo-machinery airfoils. Test runs are made and the results are discussed to assess how robust the tool is and how the current capabilities can be modified or extended. After the development process, the tool is verified to be a suitable option for real-life design optimization tasks and can be used as a building block for a much more comprehensive tool that may be developed in the future.<br>Automatisering av processen för design av vingprofiler kräver fortlöpande insatser inom området turbomaskindesign, med stort fokus på att utveckla nya tillförlitliga och konsekventa metoder som kan tillgodose ingenjörernas behov. Ett stort antal olika tillvägagångssätt har provats för omvänd design av vingprofiler såsom teoretisk invers design, statistiska metoder, empiriska upptäckter och många andra sätt att lösa designproblemet. Detta avhandlingsarbete är också ett lyckat försök att utveckla ett verktyg i Python som ska användas i den aerodynamiska designprocessen; det är enkelt, snabbt och noggrant för den initiala designen av turbomaskinblad med fokus på turbinblad som för användning i flygmotorer. För att förmedla beslutsprocessen under utvecklingen presenteras ett förenklat fall. De underliggande övervägandena diskuteras. Andra tillgängliga metoder i litteraturen som används för liknande problem utvärderas och jämförs för att visa fördelarna och begränsningarna med de metoder som används i verktyget. Det omvända designproblemet formuleras som ett multi-objektivt optimeringsproblem för att hantera olika mål som är relevanta för aerodynamisk design av turbomaskiner. Testkörningar görs och resultaten diskuteras för att bedöma hur robust verktyget är och hur de nuvarande funktionerna kan modifieras eller utökas. Efter utvecklingsprocessen verifieras verktyget som ett lämpligt alternativ för verkliga designoptimeringsuppgifter och kan användas som en byggsten för ett mycket mer omfattande verktyg som kan utvecklas i framtiden.
35
Klostermeier, Christian. "Investigation into the capability of large eddy simulation for turbomachinery design." Thesis, University of Cambridge, 2008. https://www.repository.cam.ac.uk/handle/1810/252106.
Full text
36
Moon, Hyung-Soo 1969. "Design of Si/SiC hybrid structures for elevated temperature micro-turbomachinery." Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/29222.
Full textAbstract:
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2002.<br>This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.<br>Includes bibliographical references.<br>thermal softening behavior at temperatures above 900 K. This thermal softening behavior limits the turbine inlet temperature, which in turn significantly degrades the overall engine efficiency. Previous studies have shown that hybrid structures of silicon and silicon carbide have good potential for improved engine performance. Detailed design of Si/SiC hybrid structures for high temperature micro-turbomachinery, however, has been hampered by the relatively poor performance of single crystal Si at elevated temperatures and high stresses and by the unavailability of accurate material properties data for both Si and SiC at the temperatures of interest. From previous work, the critical structures and materials issues to be resolved, in order to proceed with the design of high temperature Si/SiC hybrid structures, were identified as follows: 1. the safety margin of the Si/SiC hybrid structures based on the upper yield strength of Si 2. reliable estimation of the service life of the Si/SiC hybrid structures 3. structural instabilities caused by the combination of stress concentrations and strain softening. In the course of this thesis, these issues provided the key motivations of the work, and have been substantially resolved. As a first step, it is critical to obtain a better understanding of the mechanical behavior of this material at elevated temperatures in order to properly exploit its capabilities as a structural material. Creep tests in simple compression with n-type single crystal silicon, with low initial dislocation density, were conducted over a temperature range of 900 K to 1200 K and a stress range of 10 MPa to 120 MPa. The compression specimens were machined such that the multi-slip <100> or <111> orientations were coincident with the compression axis.<br>(cont.) The creep tests reveal that the response can be delineated into two broad regimes: (a) in the first regime rapid dislocation multiplication is responsible for accelerating creep rates, and (b) in the second regime an increasing resistance to dislocation motion is responsible for the decelerating creep rates, as is typically observed for creep in metals. An isotropic elasto-viscoplastic constitutive model that accounts for these two mechanisms has been developed in support of the design of the high temperature turbine structure of the MIT microengine. From the experimental observations and model validation, basic guidelines for the design of Si/SiC hot structures have been provided. First, the use of the upper yield strength of single crystal Si for design purpose is non-conservative. Also from the perspective of the design of Si hot structures, the lower yield strength is insufficient, particularly for micro-turbomachinery operating at elevated temperatures and high stresses. The recommended approach to the design of Si hot structures is to use the Si model for extracting appropriate operating conditions, and to reinforce the Si structures with SiC in strategic locations. Second, at high temperatures, the effect of stress concentrations is not crucial ...<br>by Hyung-Soo Moon.<br>Ph.D.
37
Abhay, Srinivas. "Novel Compressor Blade Design Study." University of Cincinnati / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1439279520.
Full text
38
Serafino, Aldo. "Méthode d'optimisation robuste multi-fidélité pour les cycles organiques de Rankine." Thesis, Paris, HESAM, 2020. http://www.theses.fr/2020HESAE055.
Full textAbstract:
L’optimisation robuste (RDO) est un outil important pour la conception de produits industriels sous incertitude. Elle combine des algorithmes d’optimisation et des techniques de quantification de l’incertitude (UQ). La quantification d’incertitudes est généralement trop coûteuse pour des modèles numériques complexes de systèmes en ingénierie. Dans le but de développer des stratégies de RDO efficaces conçues pour des applications industrielles, le couplage de techniques UQ parcimonieuses avec un algorithme génétique multi-objectif basé sur des modèles substituts (SMOGA) a été étudié. A cet égard, une technique RDO prometteuse a été utilisée, basée sur le couplage de deux modèles substituts imbriqués: le premier est utilisé pour l’UQ, tandis que la surface de réponse du second est utilisée pour accélérer l’optimisation; un critère d’enrichissement est utilisé pour actualiser le modèle substitut pendant la convergence de l’optimiseur. Plusieurs méthodes d’UQ utilisant des informations sur les gradients de la solution par rapport aux variables incertaines ont été mises en oeuvre et comparées en termes de précision et coût de calcul. Nous avons ensuite sélectionné une méthode UQ dite «basse fidélité», c’est-à-dire peu coûteuse mais pas très précise, et une méthode «haute fidélité» afin de construire un modèle substitut multi-fidélité pour l’optimisation robuste. Ce modèle permet d’avoir une précision proche du modèle haute fidélité pour un coût de calcul bien moindre. Les méthodes étudiées ont été appliquées à la RDO de cycles thermodynamiques de Rankine à fluide organique (ORC) et à l’optimisation de forme d’une grille d’aubes de turbines ORC avec des résultats très prometteurs<br>Robust design optimization (RDO) is an important tool for the design of industrial products underuncertainty. It combines optimization algorithms and uncertainty quantification (UQ) techniques. Quantificationof uncertainties is generally too expensive for complex numerical models of engineering systems. With the aimof developing efficient RDO strategies designed for industrial applications, the coupling of parsimonious UQtechniques with a multi-objective genetic algorithm based on surrogate models (SMOGA) was studied. In thisregard, a promising RDO technique was used, based on the coupling of two nested surrogate models: the firstis used for UQ, while the response surface of the second is used to accelerate optimization; an infill criterion isused to update the surrogate model during optimizer convergence. Several UQ methods using information onthe gradients of the solution with respect to the uncertain variables were implemented and compared in termsof precision and computational cost. We then selected a so-called “low fidelity” UQ method, i.e. inexpensivebut not very accurate, and a “high fidelity” method in order to build a multi-fidelity surrogate model for robustoptimization. This model allows to have an accuracy close to the high fidelity model for a much lower computationcost. The methods under investigation were applied to the RDO of organic Rankine cycles (ORC) and to theshape optimization of an ORC turbine blade grid, with very promising results
39
Roddis, Mark Edward. "On the inverse design of marine ducted propulsor blading." Thesis, University College London (University of London), 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.265865.
Full text
40
Nemnem, Ahmed M. F. "A General Multidisciplinary Turbomachinery Design Optimization system Applied to a Transonic Fan." University of Cincinnati / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1415283694.
Full text
41
Chadha, Raman. "Design of high efficiency blowers for future aerosol applications." Texas A&M University, 2005. http://hdl.handle.net/1969.1/5002.
Full textAbstract:
High efficiency air blowers to meet future portable aerosol sampling applications were
designed, fabricated, and evaluated. A Centrifugal blower was designed to achieve a flow
rate of 100 L/min (1.67 x 10^-3 m^3/s) and a pressure rise of WC " 4 (1000 PA). Commercial
computational fluid dynamics (CFD) software, FLUENT 6.1.22, was used extensively
throughout the entire design cycle. The machine, Reynolds number (Re) , was around 10^5
suggesting a turbulent flow field. Renormalization Group (RNG) úâÂÂõ turbulent model
was used for FLUENT simulations. An existing design was scaled down to meet the
design needs. Characteristic curves showing static pressure rise as a function of flow rate
through the impeller were generated using FLUENT and these were validated through
experiments.
Experimentally measured efficiency (÷EXP) for the base-design was around 10%. This
was attributed to the low efficiency of the D.C. motor used. CFD simulations, using the
úâÂÂõ turbulent model and standard wall function approach, over-predicted the pressure
rise values and the percentage error was large.
Enhanced wall function under-predicted the pressure rise but gave better agreement (less
than 6% error) with experimental results. CFD predicted a blower scaled 70% in planar
direction (XZ) and 28% in axial direction (Y) and running at 19200 rpm
(70xz_28y@19.2k) as the most appropriate choice. The pressure rise is 1021 Pa at the design flow rate of 100 L/min. FLUENT predicts an efficiency value based on static head
(÷FLU) as 53.3%. Efficiency value based on measured static pressure rise value and the
electrical energy input to the motor (÷EXP) is 27.4%. This is almost a 2X improvement
over the value that one gets with the hand held vacuum system blower.
42
Mayorca, María Angélica. "Development and Validation of a Numerical Tool for theAeromechanical Design of Turbomachinery." Licentiate thesis, KTH, Energy Technology, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-11992.
Full textAbstract:
<p>In aeromechanical design one of the major rules is to operate under High Cyclic Fatigue (HCF) margins and away from flutter. The level of dynamic excitations and risk of HCF can be estimated by performing forced response analyses from blade row interaction forces or Low Engine Order (LEO) excitation mechanisms. On the other hand, flutter stability prediction can be assessed by calculation of aerodynamic damping forces due to blade motion. In order to include these analyses as regular practices in an industrial aeromechanical design process, interaction between the fields of fluid and structural dynamics must be established in a rather simple yet accurate manner. Effects such as aerodynamic and structural mistuning should also be taken into account where parametric and probabilistic studies take an important role.</p><p>The present work presents the development and validation of a numerical tool for aeromechanical design. The tool aims to integrate in a standard and simple manner regular aeromechanical analysis such as forced response analysis and aerodynamic damping analysis of bladed disks.</p><p>Mistuning influence on forced response and aerodynamic damping is assessed by implementing existing model order reduction techniques in order to decrease the computational effort and assess results in an industrially applicable time frame. The synthesis program solves the interaction of structure and fluid from existing Finite Element Modeling (FEM) and Computational Fluid Dynamics (CFD) solvers inputs by including a mapping program which establishes the fluid and structure mesh compatibility. Blade row interaction harmonic forces and/or blade motion aerodynamic damping forces are inputs from unsteady fluid dynamic solvers whereas the geometry, mass and stiffness matrices of a blade alone or bladed disk sector are inputs from finite element solvers. Structural and aerodynamic damping is also considered.</p><p>Structural mistuning is assessed by importing different sectors and any combinations of the full disk model can be achieved by using Reduced Order Model (ROM) techniques. Aerodynamic mistuning data can also be imported and its effects on the forced response and stability assessed. The tool is developed in such a way to allow iterative analysis in a simple manner, being possible to realize aerodynamically and structurally coupled analyses of industrial bladed disks. A new method for performing aerodynamic coupled forced response and stability analyses considering the interaction of different mode families has also been implemented. The method is based on the determination of the aerodynamic matrices by means of least square approximations and is here referred as the Multimode Least Square (MLS) method.</p><p>The present work includes the program description and its applicability is assessed on a high pressure ratio transonic compressor blade and on a simple blisk.</p><br>Turbopower<br>AROMA
43
Chernysheva, Olga V. "Flutter in sectored turbine vanes." Doctoral thesis, KTH, Energy Technology, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3737.
Full textAbstract:
<p>In order to eliminate or reduce vibration problems inturbomachines without a high increase in the complexity of thevibratory behavior, the adjacent airfoils around the wheel areoften mechanically connected together with lacing wires, tip orpart-span shrouds in a number of identical sectors. Although anaerodynamic stabilizing effect of tying airfoils together ingroups on the whole cascade is indicated by numerical andexperimental studies, for some operating conditions suchsectored vane cascade can still remain unstable.</p><p>The goal of the present work is to investigate thepossibilities of a sectored vane cascade to undergoself-excited vibrations or flutter. The presented method forpredicting the aerodynamic response of a sectored vane cascadeis based on the aerodynamic work influence coefficientrepresentation of freestanding blade cascade. The sectored vaneanalysis assumes that the vibration frequency is the same forall blades in the sectored vane, while the vibration amplitudesand mode shapes can be different for each individual blade inthe sector. Additionally, the vibration frequency as well asthe amplitudes and mode shapes are supposed to be known.</p><p>The aerodynamic analysis of freestanding blade cascade isperformed with twodimensional inviscid linearized flow model.As far as feasible the study is supported by non-linear flowmodel analysis as well as by performing comparisons againstavailable experimental data in order to minimize theuncertainties of the numerical modeling on the physicalconclusions of the study.</p><p>As has been shown for the freestanding low-pressure turbineblade, the blade mode shape gives an important contributioninto the aerodynamic stability of the cascade. During thepreliminary design, it has been recommended to take intoaccount the mode shape as well rather than only reducedfrequency. In the present work further investigation using foursignificantly different turbine geometries makes these findingsmore general, independent from the low-pressure turbine bladegeometry. The investigation also continues towards a sectoredvane cascade. A parametrical analysis summarizing the effect ofthe reduced frequency and real sector mode shape is carried outfor a low-pressure sectored vane cascade for differentvibration amplitude distributions between the airfoils in thesector as well as different numbers of the airfoils in thesector. Critical (towards flutter) reduced frequency maps areprovided for torsion- and bending-dominated sectored vane modeshapes. Utilizing such maps at the early design stages helps toimprove the aerodynamic stability of low-pressure sectoredvanes.</p><p>A special emphasis in the present work is put on theimportance for the chosen unsteady inviscid flow model to bewell-posed during numerical calculations. The necessity for thecorrect simulation of the far-field boundary conditions indefining the stability margin of the blade rows isdemonstrated. Existing and new-developed boundary conditionsare described. It is shown that the result of numerical flowcalculations is dependent more on the quality of boundaryconditions, and less on the physical extension of thecomputational domain. Keywords: Turbomachinery, Aerodynamics,Unsteady CFD, Design, Flutter, Low-Pressure Turbine, Blade ModeShape, Critical Reduced Frequency, Sectored Vane Mode Shape,Vibration Amplitude Distribution, Far-field 2D Non-ReflectingBoundary Conditions. omain.</p><p><b>Keywords:</b>Turbomachinery, Aerodynamics, Unsteady CFD,Design, Flutter, Low-Pressure Turbine, Blade Mode Shape,Critical Reduced Frequency, Sectored Vane Mode Shape, VibrationAmplitude Distribution, Far-field 2D Non-Reflecting BoundaryConditions.</p>
44
Mayorca, María Angélica. "Development and Validation of a Numerical Tool for the Aeromechanical Design of Turbomachinery." Licentiate thesis, KTH, Kraft- och värmeteknologi, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-11992.
Full textAbstract:
In aeromechanical design one of the major rules is to operate under High Cyclic Fatigue (HCF) margins and away from flutter. The level of dynamic excitations and risk of HCF can be estimated by performing forced response analyses from blade row interaction forces or Low Engine Order (LEO) excitation mechanisms. On the other hand, flutter stability prediction can be assessed by calculation of aerodynamic damping forces due to blade motion. In order to include these analyses as regular practices in an industrial aeromechanical design process, interaction between the fields of fluid and structural dynamics must be established in a rather simple yet accurate manner. Effects such as aerodynamic and structural mistuning should also be taken into account where parametric and probabilistic studies take an important role. The present work presents the development and validation of a numerical tool for aeromechanical design. The tool aims to integrate in a standard and simple manner regular aeromechanical analysis such as forced response analysis and aerodynamic damping analysis of bladed disks. Mistuning influence on forced response and aerodynamic damping is assessed by implementing existing model order reduction techniques in order to decrease the computational effort and assess results in an industrially applicable time frame. The synthesis program solves the interaction of structure and fluid from existing Finite Element Modeling (FEM) and Computational Fluid Dynamics (CFD) solvers inputs by including a mapping program which establishes the fluid and structure mesh compatibility. Blade row interaction harmonic forces and/or blade motion aerodynamic damping forces are inputs from unsteady fluid dynamic solvers whereas the geometry, mass and stiffness matrices of a blade alone or bladed disk sector are inputs from finite element solvers. Structural and aerodynamic damping is also considered. Structural mistuning is assessed by importing different sectors and any combinations of the full disk model can be achieved by using Reduced Order Model (ROM) techniques. Aerodynamic mistuning data can also be imported and its effects on the forced response and stability assessed. The tool is developed in such a way to allow iterative analysis in a simple manner, being possible to realize aerodynamically and structurally coupled analyses of industrial bladed disks. A new method for performing aerodynamic coupled forced response and stability analyses considering the interaction of different mode families has also been implemented. The method is based on the determination of the aerodynamic matrices by means of least square approximations and is here referred as the Multimode Least Square (MLS) method. The present work includes the program description and its applicability is assessed on a high pressure ratio transonic compressor blade and on a simple blisk.<br>QC 20110324<br>Turbopower<br>AROMA
45
Cevik, Mert. "Desifn And Optimization Of A Mixed Flow Compressor Impeller Using Robust Design Methods." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/12611105/index.pdf.
Full textAbstract:
This is a study that is focused on developing an individual design methodology for a centrifugal impeller and generating a mixed flow impeller for a small turbojet engine by using this methodology. The structure of the methodology is based on the design, modeling and the optimization processes, which are operated sequentially. The design process consists of
engine design and compressor design codes operated together with a commercial design code. Design of Experiment methods and an in-house Neural Network code is used for the modeling phase. The optimization is based on an in-house code which is generated based on multidirectional search algorithm. The optimization problem is constructed by using the inhouse parametric design codes of the engine and the compressor. The goal of the optimization problem is to reach an optimum design which gives the best possible combination of the thrust and the fuel consumption for a small turbojet engine.
The final combination of the design parameters obtained from the optimization study are used in order to generate the final design with the commercial design code. On the last part of the thesis a comparison of the final design and a standard radial flow impeller is made in order to clarify the benefit of the study. The results have been showed that a mixed flow
compressor design is superior to a standard radial flow compressor in a small turbojet application.
46
Ugolotti, Matteo. "Implementation and Evaluation of Machine Learning Assisted Adjoint Sensitivities Applied to Turbomachinery Design Optimization." University of Cincinnati / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1593267985073912.
Full text
47
Iyengar, Vishwas. "A First Principles Based Methodology for Design of Axial Compressor Configurations." Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/16163.
Full textAbstract:
Axial compressors are widely used in many aerodynamic applications. The design of an axial compressor configuration presents many challenges. Until recently, compressor design was done using 2-D viscous flow analyses that solve the flow field around cascades or in meridional planes or 3-D inviscid analyses. With the advent of modern computational methods it is now possible to analyze the 3-D viscous flow and accurately predict the performance of 3-D multistage compressors. It is necessary to retool the design methodologies to take advantage of the improved accuracy and physical fidelity of these advanced methods.
In this study, a first-principles based multi-objective technique for designing single stage compressors is described. The study accounts for stage aerodynamic characteristics, rotor-stator interactions and blade elastic deformations. A parametric representation of compressor blades that include leading and trailing edge camber line angles, thickness and camber distributions was used in this study A design of experiment approach is used to reduce the large combinations of design variables into a smaller subset. A response surface method is used to approximately map the output variables as a function of design variables. An optimized configuration is determined as the extremum of all extrema.
This method has been applied to a rotor-stator stage similar to NASA Stage 35. The study has two parts: a preliminary study where a limited number of design variables were used to give an understanding of the important design variables for subsequent use, and a comprehensive application of the methodology where a larger, more complete set of design variables are used. The extended methodology also attempts to minimize the acoustic fluctuations at the rotor-stator interface by considering a rotor-wake influence coefficient (RWIC). Results presented include performance map calculations at design and off-design speed along with a detailed visualization of the flow field at design and off-design conditions.
The present methodology provides a way to systematically screening through the plethora of design variables. By selecting the most influential design parameters and by optimizing the blade leading edge and trailing edge mean camber line angles, phenomenon s such as tip blockages, blade-to-blade shock structures and other loss mechanisms can be weakened or alleviated. It is found that these changes to the configuration can have a beneficial effect on total pressure ratio and stage adiabatic efficiency, thereby improving the performance of the axial compression system. Aeroacoustic benefits were found by minimizing the noise generating mechanisms associated with rotor wake-stator interactions. The new method presented is reliable, low time cost, and easily applicable to industry daily design optimization of turbomachinery blades.
48
Leger, Timothy James. "Development of an Unsteady Aeroelastic Solver for the Analysis of Modern Turbomachinery Designs." Wright State University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=wright1283588070.
Full text
49
Naber, Logan A. "High Pressure Ratio Compressor Performance Design and Optimization." University of Cincinnati / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1626357000628287.
Full text
50
Schwalbach, Marc [Verfasser], and Nicolas R. [Akademischer Betreuer] Gauger. "An Efficient CAD-Based Multidisciplinary Optimization Framework for Turbomachinery Design / Marc Schwalbach ; Betreuer: Nicolas R. Gauger." Kaiserslautern : Technische Universität Kaiserslautern, 2021. http://d-nb.info/1228334285/34.
Full text