Dissertations / Theses on the topic 'Moving boundary'
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Vuta, Ravi K. "Numerical simulation of moving boundary problem." Link to electronic thesis, 2007. http://www.wpi.edu/Pubs/ETD/Available/etd-050407-082551/.
Full textZerroukat, Mohamed. "Numerical computation of moving boundary phenomena." Thesis, University of Glasgow, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285256.
Full textBailey, R. H. "Unstructured grid methods and moving boundary problems." Thesis, Swansea University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.636006.
Full textMoody, R. O. "The numerical solution of moving-boundary problems using moving-finite-element methods." Thesis, University of Reading, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383463.
Full textTremel, U. W. "Parallel unstructured adaptive remeshing for moving boundary problems." Thesis, Swansea University, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.496680.
Full textle, coupanec erwan. "Boundary conditions for the lattice Boltzmann method : Mass conserving boundary conditions for moving walls." Thesis, Norwegian University of Science and Technology, Department of Energy and Process Engineering, 2010. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-10154.
Full textBased on the no-slip boundary condition for walls at rest for the lattice Boltzmann Bathnagar-Gross-Krook method by J.C.G. Verschaeve [Phys. Rev. 80,036703 (2009)], a no-slip boundary condition for walls with a tangential movement is derived. Numerical tests verify that the present boundary condition is second order accurate and stable for relaxation frequencies close to two.
Tsuji, Tetsuro. "Studies on Moving Boundary Problems in Rarefied Gas Dynamics." 京都大学 (Kyoto University), 2013. http://hdl.handle.net/2433/174878.
Full textDufresne, Sophie. "Optimization of an airfoil's performance through moving boundary control." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-09292009-020211/.
Full textMorrow, Liam Christopher. "A numerical investigation of Darcy-type moving boundary problems." Thesis, Queensland University of Technology, 2020. https://eprints.qut.edu.au/204264/1/Liam_Morrow_Thesis.pdf.
Full textChiang, Sio Iam. "Reflected stochastic differential equations with a random and moving boundary." Thesis, University of Macau, 2000. http://umaclib3.umac.mo/record=b1446666.
Full textMokhtarian, Farzad. "Fluid dynamics of airfoils with moving surface boundary-layer control." Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/29026.
Full textApplied Science, Faculty of
Mechanical Engineering, Department of
Graduate
Araki, Daisuke. "Boundary-layer separation on a moving surface in supersonic flow." Thesis, University of Manchester, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.488392.
Full textCai, Shang-Gui. "Computational fluid-structure interaction with the moving immersed boundary method." Thesis, Compiègne, 2016. http://www.theses.fr/2016COMP2276/document.
Full textIn this thesis a novel non-body conforming mesh formulation is developed, called the moving immersed boundary method (MIBM), for the numerical simulation of fluid-structure interaction (FSI). The primary goal is to enable solids of complex shape to move arbitrarily in an incompressible viscous fluid, without fitting the solid boundary motion with dynamic meshes. This novel method enforces the no-slip boundary condition exactly at the fluid-solid interface with a boundary force, without introducing any artificial constants to the rigid body formulation. As a result, large time step can be used in current method. To determine the boundary force more efficiently in case of moving boundaries, an additional moving force equation is derived and the resulting system is solved by the conjugate gradient method. The proposed method is highly portable and can be integrated into any fluid solver as a plug-in. In the present thesis, the MIBM is implemented in the fluid solver based on the projection method. In order to obtain results of high accuracy, the rotational incremental pressure correction projection method is adopted, which is free of numerical boundary layer and is second order accurate. To accelerate the calculation of the pressure Poisson equation, the multi-grid method is employed as a preconditioner together with the conjugate gradient method as a solver. The code is further parallelized on the graphics processing unit (GPU) with the CUDA library to enjoy high performance computing. At last, the proposed MIBM is applied to the study of two-way FSI problem. For stability and modularity reasons, a partitioned implicit scheme is selected for this strongly coupled problem. The interface matching of fluid and solid variables is realized through a fixed point iteration. To reduce the computational cost, a novel efficient coupling scheme is proposed by removing the time-consuming pressure Poisson equation from this fixed point interaction. The proposed method has shown a promising performance in modeling complex FSI system
Ilić, Milos̆. "A class of moving boundary problems arising in drying processes." Thesis, Queensland University of Technology, 1991.
Find full textSuzuki, Kosuke. "An immersed boundary-lattice Boltzmann method for moving boundary flows and its application to flapping flight." 京都大学 (Kyoto University), 2014. http://hdl.handle.net/2433/188584.
Full textMarella, Saikrishna V. Udaykumar H. S. "A Parallelized sharp-interface fixed grid method for moving boundary problems." Thesis supplements, 2006. http://ir.uiowa.edu/etd/88.
Full textPrimo, Ana Rosa Mendes. "Novel boundary integral formulations for slow viscous flow with moving boundaries." Thesis, Brunel University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242986.
Full textMarella, Saikrishna V. "A Parallelized sharp-interface fixed grid method for moving boundary problems." Diss., University of Iowa, 2006. https://ir.uiowa.edu/etd/88.
Full textBjøntegaard, Tormod. "High order methods for incompressible fluid flow: Application to moving boundary problems." Doctoral thesis, Norwegian University of Science and Technology, Department of Mathematical Sciences, 2008. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-2232.
Full textBaig, Saood Saeed. "A simple moving boundary technique and its application to supersonic inlet starting /." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=112555.
Full textThe developed technique is rather general and can be used with virtually any finite-volume or finite-difference scheme, since the modifications of the schemes themselves are not required. In the present study the proposed technique has been incorporated into a one-dimensional non-adaptive Euler code and a two-dimensional locally adaptive unstructured Euler code.
It is shown that the new approach is conservative with the order of approximation near the moving boundaries. To reduce the conservation error, it is beneficial to use the method in conjunction with local grid adaptation.
The technique is verified for a number of one and two dimensional test cases with analytical solutions. It is applied to the problem of supersonic inlet starting via variable geometry approach. At first, a classical starting technique of changing exit area by a moving wedge is numerically simulated. Then, the feasibility of some novel ideas such as a collapsing frontal body and "tractor-rocket" are explored.
Castro, Nicholas D. "Numerical Modeling of Synthetic Jets in Quiescent Air with Moving Boundary Conditions." VCU Scholars Compass, 2005. http://scholarscompass.vcu.edu/etd/1466.
Full textLippoth, Friedrich-Matthias [Verfasser]. "Singular limits and maximally continued solutions of moving boundary problems / Friedrich-Matthias Lippoth." Hannover : Technische Informationsbibliothek und Universitätsbibliothek Hannover, 2010. http://d-nb.info/1004973764/34.
Full textWahab, A. K. "A finite element solution to the shallow water equations incorporating a moving boundary." Thesis, Swansea University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.639320.
Full textHussain, Amer. "A Numerical Study of Compressible Lid Driven Cavity Flow with a Moving Boundary." ScholarWorks@UNO, 2016. http://scholarworks.uno.edu/td/2155.
Full textChen, Yuhao. "Conforming to interface structured adaptive mesh refinement technique for modeling moving boundary problems." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1492428866626613.
Full textMcCarvill, John. "The dynamics of a moving boundary between immiscible fluids in a porous medium /." Online version of thesis, 1991. http://hdl.handle.net/1850/11003.
Full textGusev, Ivan. "A mathematical study of the effect of a moving boundary and a thermal boundary layer on droplet heating and evaporation." Thesis, University of Brighton, 2012. https://research.brighton.ac.uk/en/studentTheses/092cc4ff-5890-4f6c-8969-f40b1afa9762.
Full textMedeiros, Luiz Adauto, and Juan Límaco. "On the Kirchhoff equation in noncylindrical domains of R." Pontificia Universidad Católica del Perú, 2014. http://repositorio.pucp.edu.pe/index/handle/123456789/97270.
Full textZhao, Xu. "Numerical study of moving boundary problems : applications in blood flow and coriolis mass flowmeters." Thesis, London South Bank University, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.618678.
Full textZhang, Hanzhong. "A moving boundary problem in a distributed parameter system with application to diode modeling." Access restricted to users with UT Austin EID, 2001. http://wwwlib.umi.com/cr/utexas/fullcit?p3037035.
Full textKrishnan, Sreedevi. "An Adaptively refined Cartesian grid method for moving boundary problems applied to biomedical systems." Diss., University of Iowa, 2006. https://ir.uiowa.edu/etd/87.
Full textChalmers, Alexander David. "Mathematical Modelling of Atherosclerosis." Thesis, The University of Sydney, 2015. http://hdl.handle.net/2123/14986.
Full textKlinga, Emil. "Modeling of the Melting Process in an AdBlue Tank." Thesis, Linköpings universitet, Fordonssystem, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-122298.
Full textTeixeira, Elizabeth. "Reflection and transmission of a plane electromagnetic wave on a moving boundary between two dielectrics." Link to electronic thesis, 2006. http://www.wpi.edu/Pubs/ETD/Available/etd-050306-154254/.
Full textYang, Jianming. "An embedded boundary formulation for large-eddy simulation of turbulent flows interacting with moving boundaries." College Park, Md. : University of Maryland, 2005. http://hdl.handle.net/1903/3083.
Full textThesis research directed by: Mechanical Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
Sikorsky, Alison A. "Concentration enhancement and device fabrication for the improved performance of gradient elution moving boundary electrophoresis." Thesis, University of Maryland, College Park, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3644192.
Full textMany recent efforts in the field of microfluidics have been focused on reducing the size and the complexity of devices and on simplifying the methods of analysis performed with them. Gradient elution moving boundary electrophoresis (GEMBE) is a recently described counterflow electrophoresis method that was developed to simplify the analysis of ions in complex matrices. In this thesis, the improvement of the limit of detection of GEMBE and reduction of the GEMBE channel length is investigated.
Integration of simple and robust device components required for the successful adaptation of many analytical methods to multiplexed and field-portable devices often has negative effects on detection sensitivity, such as in the optical detection components in a capillary electrophoresis (CE) system. One of the simplest methods to improve sensitivity in the CE field is known as sample stacking. This method involves preparing the sample in a buffer with a different concentration (and conductivity) than that of the run buffer, such that when an electric field is applied the analyte concentration is increased at the boundary between the two different buffer concentrations. A method in which the sample is prepared in a buffer at a lower concentration than the run buffer has been implemented. This method achieves a significantly greater signal enhancement than expected for sample stacking. The concentration enhancement ability of this method is demonstrated utilizing GEMBE with channel current detection.
Current GEMBE device construction methods impose limitations on the minimum length of the separation channel. One technique well suited for minimizing the size of the GEMBE separation channel is multiphoton absorption polymerization (MAP). Because MAP is a non-linear optical fabrication method, polymerization is limited to a small region near the focal point of a laser beam. As a result, three-dimensional structures with small feature sizes can be easily created. The 3D capabilities of MAP have been exploited to create channels with circular cross sections and ∼300 &mgr;m lengths for GEMBE. The integration of device components fabricated with MAP and molded with PMDS allows visualization of the GEMBE separations, and provides insights into the effect of channel length on GEMBE step width.
Narimanyan, Arsen. "Stefan-Signorini moving boundary problem arisen from thermal plasma cutting mathematical modelling, analysis and numerical solution /." [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=980807719.
Full textPiqueras, García Miguel Ángel. "Numerical Methods for Multidisciplinary Free Boundary Problems: Numerical Analysis and Computing." Doctoral thesis, Universitat Politècnica de València, 2018. http://hdl.handle.net/10251/107948.
Full textMany problems in science and engineering are formulated as partial differential equations (PDEs). If the boundary of the domain where these equations are to be solved is not known a priori, we face "Free-boundary problems", which are characteristic of non-time dependent stationary systems; besides, we have "Moving-boundary problems" in temporal evolution processes, where the border changes over time. The solution to these problems is given by the expression of the dependent variable(s) of PDE(s), together with the function that determines the position of the boundary. Since the analytical solution of this type of problems is lacked in most cases, it is necessary to resort to numerical methods that allow an accurate enough solution to be obtained, and which also maintain the qualitative properties of the solution(s) of the continuous model. This work approaches the numerical study of some moving-boundary problems that arise in different disciplines. The applied methodology consists of two successive steps: firstly, the so-called Landau transformation, or "Front-fixing transformation", which is used in the PDE(s) model to maintain the boundary of the domain immobile; later, we proceed to its discretization with a finite difference scheme. Different numerical schemes are obtained and implemented through the MATLAB computational tool. Properties of the scheme and the numerical solution (positivity, stability, consistency, monotonicity, etc.) are studied by an exhaustive numerical analysis. The first chapter of this work reports the state of the art of the field under study, justifies the need to adapt numerical methods to this type of problem, and briefly describes the methodology used in our approach. Chapter 2 presents a problem in Mathematical Biology that consists in determining over time the evolution of an invasive species population that spreads in a habitat. This problem is modelled by a diffusion-reaction equation linked to a Stefan-type condition. The results of the numerical analysis confirm the existence of a spreading-vanishing dichotomy in the long-term evolution of the population density of the invasive species. In particular, it is possible to determine the value of the coefficient of the Stefan condition that separates the propagation behaviour from extinction. Chapters 3 and 4 focus on a problem of Concrete Chemistry with an interest in Civil Engineering: the carbonation of concrete, an evolutionary phenomenon that leads to the progressive degradation of the affected structure and its eventual ruin if preventive measures are not taken. Chapter 3 considers a system of two parabolic type PDEs with two unknowns. For its resolution, the initial and boundary conditions have to be considered together with the Stefan conditions on the carbonation front. The numerical analysis results agree with those obtained in a previous theoretical study. The dynamics of the concentrations and the moving boundary confirm the long-term behaviour of the evolution law for the moving boundary as a "square root of time". Chapter 4 considers a more general model than the previous one, which includes six chemical species, defined in both the carbonated and non-carbonated zones, whose concentrations have to be found. Chapter 5 addresses a heat transfer problem that appears in various industrial processes; in this case, the solidification of metals in casting processes, where the solid phase advances and liquid reduces until it is depleted. The moving boundary (the solidification front) separates both phases. Its position in each instant is the variable to be determined together with the temperature profiles in both phases. After suitable transformation, discretization is carried out to obtain a finite difference scheme to be implemented. The process was subdivided into three temporal stages to deal with the singularities associated with the moving boundary position in the initialisation and depletion stages.
Multitud de problemes en ciència i enginyeria es plantegen com a equacions en derivades parcials (EDPs). Si la frontera del recinte on eixes equacions han de satisfer-se es desconeix a priori, es parla de "Problemas de frontera lliure", propis de sistemes estacionaris no dependents del temps, o bé de "Problemas de frontera mòbil", associats a problemes d'evolució temporal, on la frontera canvia amb el temps. Atés que este tipus de problemes manca en la majoria dels casos de solució analítica coneguda, es fa precís recórrer a mètodes numèrics que permeten obtindre una solució prou aproximada a l'exacta, i que a més mantinga propietats qualitatives de la solució del model continu d'EDP(s). En aquest treball s'ha abordat l'estudi numèric d'alguns problemes de frontera mòbil provinents de diverses disciplines. La metodologia aplicada consta de dos passos successius: en primer lloc, s'aplica l'anomenada transformació de Landau o "Front-fixing transformation" al model en EDP(s) a fi de mantindre immòbil la frontera del domini; posteriorment, es procedix a la seva discretització a través d'un esquema en diferències finites. D'ací s'obtenen esquemes numèrics que s'implementen per mitjà de la ferramenta informàtica MATLAB. Per mitjà d'una exhaustiva anàlisi numèrica, s'estudien propietats de l'esquema i de la solució numèrica (positivitat, estabilitat, consistència, monotonia, etc.). En el primer capítol d'aquest treball es revisa l'estat de l'art del camp objecte d'estudi, es justifica la necessitat de disposar de mètodes numèrics adaptats a aquest tipus de problemes i es descriu breument la metodologia emprada en el nostre enfocament. El Capítol 2 es dedica a un problema pertanyent a la Biologia Matemàtica i que consistix a determinar l'evolució en el temps de la distribució de la població d'una espècie invasora que es propaga en un hàbitat. Este model consistix en una equació de difusió-reacció unida a una condició tipus Stefan, que relaciona les funcions solució i frontera mòbil a determinar. Els resultats de l'anàlisi numèrica confirmen l'existència d'una dicotomia propagació-extinció en l'evolució a llarg termini de la densitat de població de l'espècie invasora. En particular, s'ha pogut precisar el valor del coeficient de la condició de Stefan que separa el comportament de propagació del d'extinció. Els Capítols 3 i 4 se centren en un problema de Química del Formigó amb interés en Enginyeria Civil: el procés de carbonatació del formigó, fenomen evolutiu que comporta la degradació progressiva de l'estructura afectada i finalment la seua ruïna, si no es prenen mesures preventives. En el Capítol 3 es considera un sistema de dos EDPs de tipus parabòlic amb dos incògnites. Per a la seua resolució, cal considerar a més, les condicions inicials, les de contorn i les de tipus Stefan en la frontera. Els resultats de l'anàlisi numèrica s'ajusten als obtinguts en un estudi teòric previ. S'han dut a terme experiments numèrics, comprovant la tendència de la llei d'evolució de la frontera mòbil cap a una funció del tipus "arrel quadrada del temps". En el Capítol 4 es considera un model més general, en el que intervenen sis espècies químiques les concentracions de les quals cal trobar, i que es troben tant en la zona carbonatada com en la no carbonatada. En el Capítol 5 s'aborda un problema de transmissió de calor que apareix en diversos processos industrials; en aquest cas, en el refredament durant la bugada de metall fos, on la fase sòlida avança i la líquida es va extingint. La frontera mòbil (front de solidificació) separa ambdues fases, sent la seua posició en cada instant la variable a determinar, junt amb les temperatures en cada una de les dos fases. Després de l'adequada transformació i discretització, s'implementa un esquema en diferències finites, subdividint el procés en tres estadis temporals, per tal de tractar les singularitats asso
Piqueras García, MÁ. (2018). Numerical Methods for Multidisciplinary Free Boundary Problems: Numerical Analysis and Computing [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/107948
TESIS
Sander, Johannes. "Weakly nonlinear unidirectional shallow water waves generated by a moving boundary : a historical essay : experiments and computations /." Zürich, 1990. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=9156.
Full textAnderson, Adam. "Studies in the improvement of two dimensional and three dimensional boundary integral methods with free moving surfaces." Thesis, University of Bristol, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386058.
Full textTambyah, Tamara. "A novel free boundary mathematical model of epithelial tissues with mechanobiological coupling." Thesis, Queensland University of Technology, 2020. https://eprints.qut.edu.au/205987/1/Tamara_Tambyah_Thesis.pdf.
Full textKaraeren, Cenker. "Numerical Simulation Of Non-reacting Turbulent Flows Over A Constant Temperature Solid Surface In Regression." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12609111/index.pdf.
Full textBorrmann, Eric Verfasser], Marek [Akademischer Betreuer] [Behr, and Holger [Akademischer Betreuer] Schüttrumpf. "Moving boundary finite element fluid flow simulation methods for marine propulsion systems / Eric Borrmann ; Marek Behr, Holger Schüttrumpf." Aachen : Universitätsbibliothek der RWTH Aachen, 2016. http://d-nb.info/116249817X/34.
Full textBorrmann, Eric [Verfasser], Marek [Akademischer Betreuer] Behr, and Holger [Akademischer Betreuer] Schüttrumpf. "Moving boundary finite element fluid flow simulation methods for marine propulsion systems / Eric Borrmann ; Marek Behr, Holger Schüttrumpf." Aachen : Universitätsbibliothek der RWTH Aachen, 2016. http://d-nb.info/116249817X/34.
Full textQiqi, Kristos. "Finite Element Approximation of a Moving Boundary Problem Arising in the Modeling of the Spin Coating Process for Thin Films." Thesis, Karlstads universitet, Institutionen för matematik och datavetenskap (from 2013), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-78234.
Full textStoor, Daniel. "Solution of the Stefan problem with general time-dependent boundary conditions using a random walk method." Thesis, Örebro universitet, Institutionen för naturvetenskap och teknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-385147.
Full textTo, Thang Long Information Technology & Electrical Engineering Australian Defence Force Academy UNSW. "Video object segmentation using phase-base detection of moving object boundaries." Awarded by:University of New South Wales - Australian Defence Force Academy. School of Information Technology and Electrical Engineering, 2005. http://handle.unsw.edu.au/1959.4/38705.
Full textGao, Haotian. "POD-Galerkin based ROM for fluid flow with moving boundaries and the model adaptation in parametric space." Diss., Kansas State University, 2018. http://hdl.handle.net/2097/38776.
Full textDepartment of Mechanical and Nuclear Engineering
Mingjun Wei
In this study, a global Proper Orthogonal Decomposition (POD)-Galerkin based Reduced Order model (ROM) is proposed. It is extended from usual fixed-domain problems to more general fluid-solid systems with moving boundaries/interfaces. The idea of the extension is similar to the immersed boundary method in numerical simulations which uses embedded forcing terms to represent boundary motions and domain changes. This immersed boundary method allows a globally defined fixed domain including both fluid and solid, where POD-Galerkin projection can be directly applied. However, such a modified approach cannot get away with the unsteadiness of boundary terms which appear as time-dependent coefficients in the new Galerkin model. These coefficients need to be pre-computed for prescribed periodic motion, or worse, to be computed at each time step for non-prescribed (e.g. with fluid-structure interaction) or non-periodic situations. Though computational time for each unsteady coefficient is smaller than the coefficients in a typical Galerkin model, because the associated integration is only in the close neighborhood of moving boundaries. The time cost is still much higher than a typical Galerkin model with constant coefficients. This extra expense for moving-boundary treatment eventually undermines the value of using ROMs. An aggressive approach is to decompose the moving boundary/domain to orthogonal modes and derive another low-order model with fixed coefficients for boundary motion. With this domain decomposition, an approach including two coupled low-order models both with fixed coefficients is proposed. Therefore, the new global ROM with decomposed approach is more efficient. Though the model with the domain decomposition is less accurate at the boundary, it is a fair trade-off for the benefit on saving computational cost. The study further shows, however, that the most time-consuming integration in both approaches, which come from the unsteady motion, has almost negligible impact on the overall dynamics. Dropping these time-consuming terms reduces the computation cost by at least one order while having no obvious effect on model accuracy. Based on this global POD-Galerkin based ROM with forcing term, an improved ROM which can handle the parametric variation of body motions in a certain range is also presented. This study shows that these forcing terms not only represent the moving of the boundary, but also decouple the moving parameters from the computation of model coefficients. The decoupling of control parameters provides the convenience to adapt the model for the prediction on states under variation of control parameters. An improved ROM including a shit mode seems promising in model adaptation for typical problems in a fixed domain. However, the benefit from adding a shit mode to model diminishes when the method is applied to moving-boundary problems. Instead, a combined model, which integrates data from a different set of parameters to generate the POD modes, provides a stable and accurate ROM in a certain range of parametric space for moving-boundary problems. By introducing more data from a different set of parameters, the error of the new model can be further reduced. This shows that the combined model can be trained by introducing more and more information. With the idea of the combined model, the improved global ROM with forcing terms shows impressive capability to predict problems with different unknown moving parameters, and can be used in future parametric control and optimization problems.
Vasyliv, Yaroslav V. "Development of general finite differences for complex geometries using immersed boundary method." Thesis, Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/54425.
Full textTran, Phu Ho. "Analyse numérique des écoulements internes au sein des moteurs à propergol solide. Vers une prise en compte des mécanismes instationnaires couplés." Thesis, Chasseneuil-du-Poitou, Ecole nationale supérieure de mécanique et d'aérotechnique, 2013. http://www.theses.fr/2013ESMA0030/document.
Full textCharacterization and simulation of internaI flow within the solid rocket motors, considering the physicalmechanisms strongly coupled, are the main focus of this thesis objective. In this context, the conjunctionbetween fluid/regression surface/fluid coupling structure imposed deploy c1ean during the development ofnumerical modeling strategy. Indeed, the model incorporates treatment coupled with an immersed boundarytracking moving boundary in order to realize the tremendous internai geometric variation experienced during ashot. Fluid side, an automatic mesh is required and the management of the latter is based on a recursivehierarchical structure development with type 2" tree. Particular attention was paid to the solver itself with anexplicit approach to time and a numerical scheme based on the approach of Roe with flow limiter in the secondorder. Tests cases were conducted to validate the sol ver and different boundary conditions introduced, inc1udingspecific conditions developed for the purpose of simulation. The first results emphasize the interest of theproposed and unless our error model, for the first time, the analysis of the sources responsible vortex instabilitiesin these engines has been studied by incorporating the effects of continuous change in geometry. Finally, thefeasibility of a strong interaction between fluid and solid solver was conducted on a simplified model of a multiengine.AlI the developments allows access to complex mechanisms coupled and strong interactions in solidrocket motors and off ers new insights into the characterization of strongly coupled mechanisms