Дисертації з теми "Inverse heat transfer problems"
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Van, Cong Tuan Son. "Numerical solutions to some inverse problems." Diss., Kansas State University, 2017. http://hdl.handle.net/2097/38248.
Повний текст джерелаDepartment of Mathematics
Alexander G. Ramm
In this dissertation, the author presents two independent researches on inverse problems: (1) creating materials in which heat propagates a long a line and (2) 3D inverse scattering problem with non-over-determined data. The theories of these methods were developed by Professor Alexander Ramm and are presented in Chapters 1 and 3. The algorithms and numerical results are taken from the papers of Professor Alexander Ramm and the author and are presented in Chapters 2 and 4.
Morales, Rebellon Juan Carlos. "Radiation exchange within enclosures of diffuse gray surfaces : the inverse problem /." Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.
Повний текст джерелаMoore, Travis J. "Application of Variation of Parameters to Solve Nonlinear Multimode Heat Transfer Problems." BYU ScholarsArchive, 2014. https://scholarsarchive.byu.edu/etd/4254.
Повний текст джерелаSilieti, Mahmood. "INVERSE BOUNDARY ELEMENT/GENETIC ALGORITHM METHOD FOR RECONSTRUCTION O." Doctoral diss., University of Central Florida, 2004. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3325.
Повний текст джерелаPh.D.
Department of Mechanical, Materials and Aerospace Engineering;
Engineering and Computer Science
Mechanical Engineering
Rogers, Craig. "PARAMETER ESTIMATION IN HEAT TRANSFER AND ELASTICITY USING TRAINED POD-RBF NETWORK INVERSE METHODS." Master's thesis, University of Central Florida, 2010. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4143.
Повний текст джерелаM.S.M.E.
Department of Mechanical, Materials and Aerospace Engineering;
Engineering and Computer Science
Mechanical Engineering MSME
Cremonini, Guilherme Ernesto Serrat de Oliveira. "Aplicação do método inverso de condução de calor na avaliação de fluidos de resfriamento para têmpera." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/18/18158/tde-11052015-125002/.
Повний текст джерелаSteels quenching involves part austenitization followed by a fast cooling to promote martensitic microstructure formation. It is necessary to evaluate quenchants in order to keep the quenching process under control. The most important cooling process parameters are the heat transfer coefficient and/or the heat flux between the quenchant and the part to be cooled. One of the methods to evaluate quenchants (cooling media) and to know what is happening inside the part during the cooling in the thermal point of view is the inverse heat conduction problem. The inverse heat conduction problem consists in the determination of parameters like heat flux, cooling rate and temperature in any position across the part, as well as the heat transfer coefficient. These parameters are obtained from temperature measurements in one or more points inside the part. The scope of this work was to develop a software based in the inverse heat conduction problem in order to evaluate quenchants for quenching. The validation of this code was made using water, soybean oil, mineral oil and NaNO3 aqueous solution.
Mansour, Salwa. "Contribution to certain physical and numerical aspects of the study of the heat transfer in a granular medium." Thesis, Rennes 1, 2015. http://www.theses.fr/2015REN1S088/document.
Повний текст джерелаIn this work, we are interested in studying heat and mass transfer in water saturated and unsaturated porous medium with a strong heating at the surface. Applications concerned are archaeology, agriculture and geothermal engineering. The first part of this work concerns the improvement of the AHC (Apparent Heat Capacity) method used in the numerical resolution of phase change problem in a homogeneous medium: the phase change temperature interval, over which the heat capacity varies, appears as a key parameter which must be chosen proportional to the mesh size. Accurate and smooth results are obtained thanks to a local refinement of the mesh near the phase change interface. The second part is about the estimation of the thermophysical properties of the soil by inverse problem using both synthetic and experimental data. The Damped Gauss-Newton and the Levenberg-Marquardt algorithms are used to solve the problem. In relation with the AHC method, the choice of the phase change temperature interval caused convergence problems which have been fixed by chaining many inverse problems. The obtained results show good convergence to the desired solution. The third part presents a simple model to calculate the effective thermal conductivity of a granular medium which contains a small quantity of liquid water. The exact shape of the liquid menisci between the grains is calculated at equilibrium. The effective thermal conductivity experiences a hysteresis behavior with respect to the liquid volume. A future work that concerns a new unsaturated model, restricted to the pendular regime and detailed at the end of this thesis, should be able to use this result
Hřibová, Veronika. "Vývoj inverzní sub-doménové metody pro výpočet okrajových podmínek vedení tepla." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2015. http://www.nusl.cz/ntk/nusl-232179.
Повний текст джерелаMusil, Jiří. "Software pro řešení inverzních úloh přenosu tepla." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2020. http://www.nusl.cz/ntk/nusl-417446.
Повний текст джерелаAZEGAMI, Hideyuki, Yutaro IWATA, Eiji KATAMINE, 秀幸 畔上, 侑太朗 岩田 та 英次 片峯. "放熱量最大化を目的とした非定常熱伝導場の形状最適化". 一般社団法人日本機械学会, 2008. http://hdl.handle.net/2237/21114.
Повний текст джерелаKůdelová, Tereza. "Řešení inverzních úloh v oblasti výměníků hmoty a tepla." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2014. http://www.nusl.cz/ntk/nusl-231153.
Повний текст джерелаGaspar, Jonathan. "Fluxmétrie et caractérisation thermiques instationnaires des dépôts des composants face au plasma du Tokamak JET par techniques inverses." Thesis, Aix-Marseille, 2013. http://www.theses.fr/2013AIXM4739/document.
Повний текст джерелаThis work deals with the successive resolution of two inverse heat transfer problems: the estimation of surface heat flux on a material and equivalent thermal conductivity of a surface layer on that material. The direct formulation is bidimensional, orthotropic (real geometry of a composite material), unsteady, non-linear and solved by finite elements. The studied materials are plasma facing components (carbon-carbon composite tiles) from Tokamak JET. The searched heat flux density varies with time and one dimension in space. The surface layers conductivity varies spatially and can vary with time during the experiment (the other thermophysical properties are temperature dependent). The two inverse problems are solved by the conjugate gradient method with the adjoint state method for the exact gradient calculation. The experimental data used for the first inverse problem resolution (surface heat flux estimation) is the thermogram provided by an embedded thermocouple. The second inverse problem uses the space and time variations of the surface temperature of the unknown surface layer (infrared thermography) for the conductivity identification. The confidence calculations associated to the estimated values are done by the Monte Carlo approach. The method developed during this thesis helps to the understanding of the plasma-wall interaction dynamic, as well as the kinetic of the surface carbon layer formation on the plasma facing components, and will be helpful to the design of the components of the future machines (WEST, ITER)
Maia, Neto Alfredo dos Santos. "Simulação computacional do processo de soldagem MIG de uma junta de topo de chapas de aço inoxidável da série 304 com deposição de material." Universidade Federal de Uberlândia, 2014. https://repositorio.ufu.br/handle/123456789/14780.
Повний текст джерелаThis work presents a 3D computational/mathematical model to solve the heat diffusion equation with phase change, considering addition of material and complex geometry. The finite volume method was used and the computational code was implemented in C++, using Borland compiler. Experimental tests were carried out for validation of the model in question. It was used a material whose thermal properties, varying with temperature, are well known: the stainless steel AISI 304. In addition, an inverse technique based on Golden Section was implemented to estimate the heat flux supplied to the sample. Experimental temperatures were measured using thermocouples type J - in a total of 07 (seven) - all connected to the metal sheet and the Agilent 34970A datalogger. The metal had a \"V\" Groove of 45°. In this location was conducted the deposition of material on only one welding pass and the dimensions (width and height) were measured after welding. The thermal model was validated from comparisons between measured and calculated temperatures. The results were consistent and validated the computational/mathematical model proposed. An innovation presented in this work consists in the calculation and visualization of the dimensions of the welding pool during welding. The complex geometry obtained proves that more studies are needed and new models must be designed to clarify and explain the formation of welding pool during welding of metal sheet.
Desenvolve-se, neste trabalho, um modelo matemático/computacional 3D (tridimensional) de difusão de calor com mudança de fase, acréscimo de material e geometria complexa. O método de volumes finitos foi implementado em linguagem C, utilizando o compilador Borland. Foram realizados testes experimentais para a validação do modelo em questão. Usou-se um material cujas propriedades térmicas, variando com a temperatura, são bem conhecidas: o aço inox AISI 304. Além do modelo direto já citado, foi implementada uma técnica inversa para o cálculo do fluxo de calor. Utilizou-se neste caso a amplamente conhecida Seção Áurea: técnica que exige uma simplificação, fluxo de calor constante ao longo do tempo de soldagem. As temperaturas na chapa foram medidas utilizando termopares do tipo J - em um total de 07 (sete) - todos ligados ao datalogger Agilent 34970A. As medições foram feitas do lado oposto à tocha de soldagem. A chapa metálica possuía um chanfro em V de 45º. Neste local foi realizada a deposição de material (reforço) em somente um passe de soldagem. As dimensões da geometria do reforço (largura e altura) foram medidas depois da realização da soldagem. Em relação aos resultados, além da comparação entre as temperaturas medidas e calculadas, foi também determinada a eficiência térmica da soldagem. Os resultados foram consistentes e validaram o modelo matemático/computacional proposto. Uma inovação apresentada neste trabalho consiste no cálculo e visualização gráfica tridimensional da poça de fusão ao longo do tempo. A complexa geometria obtida comprova que mais estudos se fazem necessários e que novos modelos devem ser concebidos para esclarecer e explicar a formação da poça de fusão durante a soldagem de chapas metálicas.
Doutor em Engenharia Mecânica
Mohebbi, Farzad. "Optimal shape design based on body-fitted grid generation." Thesis, University of Canterbury. Mechanical Engineering, 2014. http://hdl.handle.net/10092/9427.
Повний текст джерелаKomínek, Jan. "Heuristické algoritmy pro optimalizaci." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2012. http://www.nusl.cz/ntk/nusl-230306.
Повний текст джерелаHadad, Waseem Al. "Thermique des mini-canaux : comportement instationnaire et approche convolutive." Thesis, Université de Lorraine, 2016. http://www.theses.fr/2016LORR0121/document.
Повний текст джерелаA semi-analytical model allowing to simulate the transient conjugate heat transfer in mini/macro plane channel subject to a heat source(s) localized on the external face(s), was presented and verified. The developed model takes into account advection-diffusion in the fluid and conduction in the solid. As the hydraulic diameter of the channel becomes small, the internal experimental characterization (measurement of temperature and heat flux) using internal sensors become tricky because internal sensors located may compromise the structural integrity of the whole system. A non-intrusive method for estimating the internal conditions from infrared temperature measurements on the external faces using the semi-analytical model was performed. Since the classic convective heat transfer coefficient loses its meaning in transient state, an alternative approach based on a transfer function, valid for Linear Time-Invariant (LTI) systems, was highlighted. This function can be calculated analytically only for a simple geometry. For complex geometries it can be estimated experimentally. Thanks to intrinsic character of this function, two characterization methods were designed. The first to estimate the temperature at a point from a measurement at another point in the system (virtual temperature sensor). The second method concerns the detection of fouling layers that may appear in the heat exchanger from temperature measurements on the external faces
Zhang, Xinxin. "Métrologie thermique par méthode quasi-stationnaire : modélisation, identification et application a la caractérisation de solides." Vandoeuvre-les-Nancy, INPL, 1993. http://www.theses.fr/1993INPL037N.
Повний текст джерелаLlanos, Luis Alberto Quezada. "Estudo experimental de estabilidade e emissão de radiação térmica em chamas não pré-misturadas de gás natural diluídas com dióxido de carbono." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/178794.
Повний текст джерелаPredicting models for turbulent diffusion flame lengths have several applications driven the attention of many research groups. Since several studies use photographs to measure the flame length, with photographic parameters varying among authors, in other cases simple visualizations were used. It is important to explore possible discrepancies among measurement technics that could affect the results. Optical visualizations of turbulent diffusion flames are used to estimate the visible average flame length (VFL) and the lift-off. The study presents a study of three different methods to measure the VFL using optical techniques. The effect on the image of the main optic parameters such as focus, exposure time and ISO sensibility are analyzed. The VFL obtained with images in low exposure time and long exposure time are compared with a third optical method that is based on the luminous intensity and the frequency of flame images occupying a pixel. One method was used to characterize the behavior of turbulent diffusion flames of natural gas for a range of flames in function of the flow velocity. Universal non-dimensional models that describe the VFL, lift-off and the blow-out stability limit of gaseous jet diffusion flames in the still air have been compared with new experimental data. The numerical coefficients of the best models are adjusted. Finally, maps of stability related to lift-off and blow-out were obtained for each diameter in function of the dilution with CO2 and flow exit velocity expressed in non-dimensional Reynolds number The third part of this work focuses on the estimation of the thermal distribution of radiative flux from turbulent diffusion flames in laboratory-scale. The experimental measurements were gotten from the previous stability study. In particular, was considered three radial distances measured in flame lengths (0,5 Lf, 1 Lf, 2 Lf) aiming at obtaining the experimental radiant flux along a vertical axis adjacent to the flames. Finally, the experimental data was used as input data in an inverse analysis with the purpose of computing weight coefficients of the weighted multi-point source (WMPS) model. Then, experimental data that include: radiant fractions and radiative heat flux are presents for several flames with different dilutions with carbon dioxide and burner´s diameters.
Loussouarn, Thomas. "Maîtrise de la thermique des fours de maintien en fonderie." Thesis, Université de Lorraine, 2018. http://www.theses.fr/2018LORR0105.
Повний текст джерелаVacuum holding induction furnaces are used for the manufacturing of turbine blades by loss wax foundry process. Heat transfer control in a holding furnace is crucial to ensure the quality of manufacturing. This work has 3 major parts, which are the detailed modelling, reduced modelling and experiments. An axyisymmetric furnace and its load have been numerically modelled using FlexPDE and COMSOL Multiphysics, finite element codes. Modelling takes as inputs the electric power consumed by inductors and gives the temperature field in the heating module. The studied reduced models are phyisical convolutive models (enthalpic (0D), 1 dimension analytical (1D)) and parametric like AutoRegressive with eXogeneous inputs (ARX). ARX models have been compared to convolutive models (identification, validation). The goal is to get temperatures in the heating module without local presence of physical sensors (virtual sensor). Detailed and reduced models have been compared to experiments on the furnace. This last part is not described in this document
Jones, Alastair Stephen. "Convection heat transfer problems." Thesis, Keele University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267356.
Повний текст джерелаBerntsson, Fredrik. "Numerical methods for inverse heat conduction problems /." Linköping : Univ, 2001. http://www.bibl.liu.se/liupubl/disp/disp2001/tek723s.pdf.
Повний текст джерелаOkamoto, Kei. "Optimal numerical methods for inverse heat conduction and inverse design solidification problems." Online access for everyone, 2005. http://www.dissertations.wsu.edu/Dissertations/Fall2005/k%5Fokamoto%5F120905.pdf.
Повний текст джерелаFigueiredo, Patric. "Iterative method for solving inverse heat conduction problems." Master's thesis, Universidade de Aveiro, 2014. http://hdl.handle.net/10773/14400.
Повний текст джерелаHorák, Aleš. "Návrh experimentu pro řešení inverzní úlohy vedení tepla." Doctoral thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2011. http://www.nusl.cz/ntk/nusl-233977.
Повний текст джерелаHussein, Mohammed Sabah. "Coefficient identification problems in heat transfer." Thesis, University of Leeds, 2016. http://etheses.whiterose.ac.uk/12291/.
Повний текст джерелаKaya, Mujdat. "Inverse Problems For A Semilinear Heat Equation With Memory." Phd thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606106/index.pdf.
Повний текст джерелаjdat Ph.D, Department of Mathematics Supervisor: Prof. Dr. A. Okay Ç
elebi Co-Supervisor: Prof. Dr. Varga Kalantarov May 2005, 79 pages In this thesis, we study the existence and uniqueness of the solutions of the inverse problems to identify the memory kernel k and the source term h, derived from First, we obtain the structural stability for k, when p=1 and the coefficient p, when g( )= . To identify the memory kernel, we find an operator equation after employing the half Fourier transformation. For the source term identification, we make use of the direct application of the final overdetermination conditions.
Hazanee, Areena. "Boundary element method for solving inverse heat source problems." Thesis, University of Leeds, 2015. http://etheses.whiterose.ac.uk/10570/.
Повний текст джерелаBuckley, Donovan O. "Solution of Nonlinear Transient Heat Transfer Problems." FIU Digital Commons, 2010. http://digitalcommons.fiu.edu/etd/302.
Повний текст джерелаCao, Kai. "Inverse problems for the heat equation using conjugate gradient methods." Thesis, University of Leeds, 2018. http://etheses.whiterose.ac.uk/22611/.
Повний текст джерелаCopiello, Diego <1980>. "Multiobjective genetic algorithms applied to heat transfer problems." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1218/.
Повний текст джерелаYi, Hak-Chae J. "Solution of time-independent inverse problems for linear transport theory /." Thesis, Connect to this title online; UW restricted, 1990. http://hdl.handle.net/1773/10677.
Повний текст джерелаLangmore, Ian. "Inverse transport with angularly averaged measurements /." Thesis, Connect to this title online; UW restricted, 2008. http://hdl.handle.net/1773/5771.
Повний текст джерелаZhong, Rong. "Inverse algorithm for determination of heat flux." Ohio : Ohio University, 2000. http://www.ohiolink.edu/etd/view.cgi?ohiou1173380355.
Повний текст джерелаIbrahim, Yasser Aly Abdel-Hamid. "Hydrodynamics, heat, and mass transfer characteristics of three-phase inverse fluidized beds." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0006/NQ42566.pdf.
Повний текст джерелаBaleine, Erwan. "ON THE USE OF VARIABLE COHERENCE IN INVERSE SCATTERING PROBLEMS." Doctoral diss., University of Central Florida, 2006. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4114.
Повний текст джерелаPh.D.
Other
Optics and Photonics
Optics
Lesnic, Daniel. "Boundary element methods for solving steady potential flow problems and direct and inverse unsteady heat conduction problems." Thesis, University of Leeds, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.404773.
Повний текст джерелаChen, Tzu-Fang. "Analytical and experimental studies for space boundary and geometry inverse heat conduction problems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ39790.pdf.
Повний текст джерелаValha, Jan. "Interfacial instability and spray heat transfer problems of two phase flow." Thesis, Middlesex University, 1996. http://eprints.mdx.ac.uk/6408/.
Повний текст джерелаChiang, Jaw-Yeong, and 江照勇. "Application of Grey Prediction to Inverse Heat Transfer Problems." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/66221404697119960269.
Повний текст джерела國立成功大學
機械工程學系碩博士班
96
This article applies Grey Prediction Method of Grey System Theory to improve the problem of errors in inverse operation due to the error of temperature measurement when analyze Inverse Heat Transfer Problems (IHTP) with Reversed Matrix Method. For IHTP, this research adopted Revered Matrix Method with Linear Least-squares Error Method to construct a linear inverse model. With finite difference method, we discretized governing equation that is designed to solve IHTP to construct a linear matrix equation. Through the re-arrangement of matrix equation, the unknown conditions (such as initial conditions, boundary conditions, thermal property or geometrical shape) could be demonstrated clearly and independently. Then substitute a small amount of successive measuring points temperature into the linear inverse model and solve the problems by Linear Least-squares Error Method. The process of inverse operation only need to measure a small amount points temperature to estimate the solution of IHTP, but in practical measurement of temperature, the errors of measurement of temperature are inevitable. Such errors will affect the accuracy of estimation value of inverse operation or even lead to an erroneous results. One of improvement method is to increase the number of temperature measurement points. Certainly, more accurate results of inverse operation we want to obtain, the number of measurement points we should increase. Therefore, this research uses the Grey Prediction Method to improve the defect with a hope that significant reduction of the number of practical temperature measurement points could also obtain the same accurate results of inverse operation. The small amount of direct temperature measurement points can increase to more amount of temperature points by Grey Prediction Method, and the temperatures of those increased points could still keep the correlations with previous temperatures from direct measurement. The increased number of temperature points could replace the number of temperature points that is necessary to increase for inverse operation. In other words, Grey Prediction Method could significantly reduce the number of practical temperature measurement points while keep the same accuracy as the results of inverse operation using a great number of direct temperature measurement points.
Tsai, Pi-Fei, and 蔡璧妃. "Estimation of transient heat transfer coefficient for 2-D inverse heat conduction problems." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/53418219955040193227.
Повний текст джерела國立成功大學
機械工程學系碩博士班
95
The study applies the method of Laplace transform and the finite difference method in conjunction with the least-squares methods, the cubic spline and the measured temperature inside the test material to predict the transient heat transfer coefficient on the boundary for the two-dimensional transient inverse heat conduction problems. For the inverse algorithm of the study, the functional form of the heat transfer coefficient is unknown a priori. The whole spatial domain is first divided into p sub-intervals. A series of connected cubic polynomial functions in space and a linear function in time are then introduced to simulate the distribution of the unknown surface heat flux over space and time for the transient inverse heat conduction problem. The study investigates into the effects of p value, the initial guesses of the unknown coefficient, the measurement locations and the measurement errors on the estimated results. The results show that when there is no temperature measurement error, a good estimation on the surface heat flux and the heat transfer coefficient can be derived with the inverse algorithm. The estimated results seem to be not very sensitive to the initial guesses, the measurement locations and the p value. Nevertheless, the predictions agree with the correct results perfectly even if there exist measurement errors, except for the long time estimations. It means that the inverse algorithm of the study presents a good accuracy.
Wu, Li-Wen, and 吳立文. "Study on Inverse Heat Transfer Problems of Force Convection in Circular Pipe." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/30006708125431734330.
Повний текст джерела國立成功大學
機械工程學系碩博士班
94
This study addresses the inverse problem of a finite cooled/heated length on the heat transfer characteristics of laminar or turbulent flows through thick-walled circular tubes. Using temperature measurements taken at several different locations within the fluid, the linear least-squares-error method is used to estimate the unknown heat flux on the external surface of the circular pipe and the unknown shape of the thermal insulation. Furthermore, the function specification method is used to estimate the time-varying inlet temperature and the outer-wall heat flux simultaneously on the basis of temperature measurements taken at two different locations within the pipe flow. While determining the steady unknown boundary conditions of the pipe flow, the present approach in this study rearranges the matrix forms of the governing differential equations, and then combines the reverse matrix method and the linear least-squares-error method. Another study about a transient inverse heat transfer problem is solved using a whole domain estimated technique with the function specification method and the linear least-squares-error method to determine the unknown boundary conditions of the pipe flow. The temperature data obtained from the direct problem are used to simulate the temperature measurement, and the influence of errors in these measurements upon the precision of the estimated results is considered. This study also considers the influence of the locations and numbers of sensors used upon the accuracy of the estimated results. The results indicate that the accuracy of the estimated results is improved by taking temperature measurements in locations close to the unknowns. The results confirm that the proposed methods are capable of yielding accurate results even when errors in the temperature measurements are present. The proposed methods provide several advantages compared to traditional methods: (1) it yields a solution within a single computational iteration, (2) no prior information is required regarding the functional form of the quantities of interest, (3) no initial guesses of the unknown parameter values are required, and (4) the inverse problem can be solved in a linear domain. This study also compares the application of the whole domain function specification method (WDFSM) and the sequential function specification method (SFSM) to the inverse problem of transient conjugate heat transfer of laminar forced convection in a circular pipe. These two inverse methods are used to estimate the time-varying inlet temperature and the outer-wall heat flux simultaneously on the basis of temperature measurements taken at two different locations within the pipe flow. The numerical results reveal that the estimations obtained from the WDFSM method are marginally better than those obtained from the SFSM approach. Finally, the performance of two classical algorithms (e.g. uniform and linear function) used in the whole domain function specification method (WDFSM) to obtain simultaneous estimates of the time-varying inlet temperature and outer-wall heat flux are compared. Additionally, this study proposes a modification to the linear assumption employed in the conventional WDFSM method to improve its estimation performance. The numerical results confirm that the proposed algorithm yields slightly more accurate estimates of the unknowns than the two classic algorithms.
許寶東. "Study of multi-dimensional inverse heat transfer problem." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/23932317774879277014.
Повний текст джерелаMirsepahi, Ali. "An intelligent approach to inverse heat transfer analysis of irradiative enclosures." Thesis, 2017. http://hdl.handle.net/2440/105377.
Повний текст джерелаThesis (Ph.D.) (Research by Publication) -- University of Adelaide, School of Chemical Engineering, 2017.
Osborne, Gregory Evan. "Novel Numerical Approaches for the Resolution of Direct and Inverse Heat Transfer Problems." 2007. http://trace.tennessee.edu/utk_graddiss/257.
Повний текст джерелаXu, Ming-Yao, and 許銘堯. "Study of Genetic Algorithm on Inverse Heat Transfer problem." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/12551962636922283344.
Повний текст джерела國立成功大學
機械工程研究所
84
In the last decade, the study of inverse heat conduction problem (IHCP) is an increasing branch of research. Usually, the mathematical models used in the study of IHCP is highly complicate. In the present study, a simple and novel methodology is adopted to solve the one-dimensional, trasient IHCP on the estimation of the unknown boundary conditions. This methodology used is the combination of Genetic Algorithms (GAs) with the finite difference method and the relative least square scheme. The mathematical model is simple. The advantage of GAs is that it is robust and the solution obtained is global optimum. Two cases are studied in this study. One is the estimation of the surface temperature with known form, the other is the estimation of the surface heat flux without the known form. For the latter case, we assume the surface heat flux is a polynomial with unknown coefficients, then those known coefficients are determined by using GAs. The influences of the noise, the number of simulated sensor data, and the location of the measurement are also investigated in the present study. The measurement error defined in the study is up to 5%. Results reveal that the better solution is obtained for the number of simulated sensor data is about 40 to 50. Also the more the location of the measurement point near the estimated boundary, the more accurate the estimation will be.
Cheng, Shun-Chung, and 鄭順中. "A Three-Dimensional Inverse Heat Transfer Problem of Estimating the Heat Generation." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/91298782736976455949.
Повний текст джерела國立成功大學
造船及船舶機械工程學系
88
We used to solve the general problem of engineering by the traditional method but in many practical problems it is very difficult therefore it can be solved by inverse method. In the present study using the Conjugate Gradient Method and the general-purpose commercial code CFX4.2-based inverse algorithm to estimate the unknown heat generation solves a three-dimensional transient inverse heat conduction problem. In the chapter 2 we use the inverse algorithm to estimate the unknown heat generation in any three-dimensional irregular composite medium and in the chapter 3 to estimate the strength of heat sources for chips on the PC-Board. The advantage of calling the CFX4.2 code as a subroutine in the present inverse calculation lies in that many difficult but practical 3-D inverse problems can be solved under this construction since the general-purpose commercial code has the ability to solve the direct problem easily. Results obtained by using the conjugate gradient method to solve these 3-D inverse problems are justified based on the numerical experiments with the simulated exact and inexact measurements. It is concluded that accurate heat generation can be estimated by the conjugate gradient method except for the final time. The reason and improvement of this singularity are addressed.
LU, WEN-SHENG, and 呂文聖. "Inverse of Resolution Heat Transfer of Electrical Discharge Machining for Two-Dimensional Nonlinear Problems." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/84450596753656856146.
Повний текст джерела國立高雄應用科技大學
模具工程系碩士班
92
This study investigates the phenomena in electric discharge machining (EDM) process which includes the relationship between the discharge energy and the machining crater outline curve, the influence of latent heat effect on the work piece, and the solution of the plasma flushing energy and the thermal conductivity coefficient. The arc, created between the work piece and the electrode in the range from a few microseconds to several hundred microseconds, produces a crater scope in this process. This crater scope, in the dimension between a few micrometers to several hundred micrometers, can be emulated by two-dimensional cylindrical coordinate by the nature of the EDM process itself presents the symmetrical type. During the machining, material will be melted by the enormous fusion heat generated in the evaporating area which will be expanded as the time increase. The solidification phenomenon will then be observed with latent heat released. This latent heat effect which causes nonlinear heat conduction problem is hard to compute by general numerical analysis, and often neglected in previous works. In this study, the average specific heat method is adopted in numerical model to effectively solve the latent heat problem. The results show the more latent heat will create the more depth of the crater. Since it is difficult to measure the inlet electric power when the arc acts on the material, however, the temperature measured from outline of crater curve in discharge process can be used to inversely solve the arc power. For the nonlinear heat transfer problem presented in this study, to the Beck’s development of the nonlinear least square method was used to deduce the numerical model, then the inlet power and the thermal physical properties can be inversely solved by this model. This study deduces the two-dimensional numerical model to simulate the EDM process. Both the direct solving and the inverse operation method were studied. The results can be contributed to the understanding of the relation of the inlet energy and the crater scope in EDM process.
Tsung-Po, Lin, and 林宗伯. "Inverse Heat Conduction Problem of Simultaneously Determining Thermal Conductivity, Heat Capacity and Heat Transfer Coefficient." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/57886664204503793306.
Повний текст джерела大同工學院
機械工程研究所
86
This study presents a theoretical approach for simultaneously estimating the thermal conductivity(k) and heat capacity(C) of a solid body as well as the heat transfer coefficient(h) on the body surface by solving an inverse heat conduction problem. The conjugate gradient method is adopted to obtain the predicted solutions. Concerning feasibility and simplification during measurement implementation, the present approach requires the recorded temperature history only at the solid surface. Three common metals, steel (Cr 18%, Ni 8%), lead, and copper, are considered as test samples for evaluating the accuracy of the approach developed. The evaluation of the accuracy is performed based on a set of pseudo-experimental temperature data which is generated by adding a time-dependent randomly-varying disturbance to the exact solution. Effects of the physical and geometric variables, including thickness of the solid plate(L), rate of heat input(q), temperature measurement error(σ), sampling period(tp), are investigated for each metal considered.
Hsiung, Tao-Yen, and 熊道彥. "The application of Boundary Element Method at Inverse Heat Transfer Problem." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/62383479656316285429.
Повний текст джерела國立成功大學
造船及船舶機械工程學系
87
An inverse design problem is solved to determine the shape of complex coolant flow passages in internal cooled turbine blades by using the conjugate gradient method (CGM). One of the advantages of using CGM lies in that it easily can handle problems having a huge number of unknown parameters and converges very fast. The boundary element method (BEM) is used to calculate the direct, sensitivity and adjoint problems due to its characteristics of easily-handling the problem considered here. Results obtained by using the CGM to solve the inverse problems are verified based on the numerical experiments in the analysis model. One concludes that the CGM is applied successfully in estimating the arbitrary shape of cavities and the rate of convergence is also very fast even when the number of unknown parameters is large. Moreover, the design model of the inverse problem is also performed to estimate the optimal shape of cooling passages in accordance with the desired blade surface temperature distributions.. The applications of inverse problems can be found in several engineering fields, such as the determination of boundary conditions, thermal properties, heat generation, contact resistance and thermal properties and thickness of frost on the tube of evaporator [1-4]. The purpose of the present study is to utilize the technique of inverse problem to estimate the thermal properties and thickness of frost on the tube of evaporator. This kind of problem is classfied as moving boundary problem as well as the inverse problem . In this paper the Conjugate Gradient Method is used for the numerical solution to the inverse geometry problem of identifying the unknown thickness of frost form temperature measurements, based on a boundary element method . The use of boundary element method is suggested bye the basic nature of the inverse problem (to search an unknown domain, thus an unknown surface), because domain discretization is avoided. More specifically, the advantages gained by BEM-based algorithm is the ability to readily accommodate the changes in the unknown boundary shape as it evolves from its initial to its final shape.
Kuo, Chi-Pin, and 郭啟彬. "Inverse Combined Conduction and Radiation Heat Transfer Problem in a Two-Layer Planar Medium." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/44801808250009657866.
Повний текст джерела國立交通大學
機械工程系
88
This study presents a systematic analysis of an inverse heat conduction-radiation problem in a two-layer planar medium by applying the space-marching technique. The use of this inverse technique allows for the estimation of the internal radiation fluxes, temperature distributions, and the surface heat flux histories, from transient temperature measurements within the semitransparent layers at two positions. The present analysis considers an absorbing, emitting, isotropically scattering and gray two-layer planar medium bounded by infinite opaque, diffusely absorbing, and diffusely reflecting surfaces. The results showed that the DDO approximation method was a precision and stable method to solve both direct and inverse combined conduction and radiation problem. Moreover, the modified space-marching technique could accurately estimate the surface fluxes and temperature histories of a inverse heat conduction-radiation problem in a semitransparent single-layer or two-layer planar medium from two internal temperature measurements with exact data (predicted values) and simulated experimental data, and the accuracy wasn’t significantly influenced by the sensor locations. The performance of the presented inverse method for a given time step was investigated. Furthermore, there exists an optimal value of grid number to obtain the minimum standard deviation. For a fixed number of grid points, the inverse solutions for the radiation dominant cases are more accurate than that of the pure conduction cases, but the sensitivity to measurement errors was almost the same.