Un grand effort a été réalisé ces dernières années dans la compréhension du champ d'écoulement et du transfert de chaleur dans les canaux de refroidissement internes présents dans les pales de turbine. En effet, des systèmes de refroidissement avancés ont non seulement conduit à l'augmentation de l'efficacité de la turbine à gaz en augmentant la température d'entrée de la turbine au-dessus de la température de fusion du matériau, mais également en augmentant la durée de vie de la turbine. Pour permettre de tels progrès, des techniques expérimentales et numériques modernes ont été largement appliquées afin d'interpréter et d'optimiser l'aérodynamique et le transfert de chaleur dans les canaux de refroidissement internes. Cependant, les données disponibles sont limitées dans le cas des canaux de refroidissement internes dans les aubes de rotor de turbine. Les gradients de rotation et de température introduisent des forces de flottabilité de type Coriolis et centripète dans le référentiel rotatif, modifiant de manière significative l'aérothermodynamique par rapport aux passages stationnaires. Dans le cas des pales de rotor de turbine, la plupart des investigations sont soit basées sur des mesures ponctuelles, soit sont contraintes à des régimes de rotation faibles. L'objectif principal de ce travail est d'étudier le débit détaillé et le transfert de chaleur d'un canal de refroidissement interne à des conditions de fonctionnement dimensionnelles sans moteur représentatives. Ce travail introduit une section d'essai en laboratoire qui exploite des canaux à nervures sur un large éventail de nombres de Reynolds, de rotation et de flottabilité. Dans le présent travail, le nombre de Reynolds va de 15,000 à 55,000, le nombre de rotation maximum est égal à 0.77 et le nombre maximal de flottabilité est égal à 0.77. La nouvelle installation expérimentale consiste en une conception polyvalente qui permet l'interchangeabilité de la géométrie testée, de sorte que les canaux de différents rapports d'aspect et les géométries de nervure peut être facilement installé. La particle image velocimetry et la thermographie à cristaux liquides sont effectuées pour fournir des mesures précises de vitesse et de transfert de chaleur dans les mêmes conditions opératoires, ce qui conduit à un ensemble de données expérimentales unique. De plus, des simulations à grands virages sont réalisées pour donner une image de l'ensemble du champ d'écoulement et compléter les observations expérimentales. En outre, l'approche numérique vise à fournir une méthodologie robuste qui est capable de fournir des prédictions haute-fidélité de la performance des canaux de refroidissement internes. / A great effort has been carried out over the recent years in the understanding of the flow field and heat transfer in the internal cooling channels present in turbine blades. Indeed, advanced cooling schemes have not only lead to the increase of the gas turbine efficiency by increasing the Turbine Inlet Temperature above the material melting temperature, but also the increase of the turbine lifespan. To allow such progresses, modern experimental and numerical techniques have been widely applied in order to interpret and optimize the aerodynamics and heat transfer in internal cooling channels. However, the available data is limited in the case of internal cooling channels in turbine rotor blades. Rotation and temperature gradients introduce Coriolis and centripetal buoyancy forces in the rotating frame of reference, modifying significantly the aerothermodynamics from that of the stationary passages. In the case of turbine rotor blades, most of the investigations are either based on point-wise measurements or are constraint to low rotational regimes. The main objective of this work is to study the detailed flow and heat transfer of an internal cooling channel at representative engine dimensionless operating conditions. This work introduces a laboratory test section that operates ribbed channels over a wide range of Reynolds, Rotation and Buoyancy numbers. In the present work, the Reynolds number ranges from 15,000 to 55,000, the maximum Rotation number is equal to 0.77, and the maximum Buoyancy number is equal to 0.77. The new experimental facility consists in a versatile design that allows the interchangeability of the tested geometry, so that channels of different aspect ratios and rib geometries can be easily fitted. Particle Image Velocimetry and Liquid Crystal Thermography are performed to provide accurate velocity and heat transfer measurements under the same operating conditions, which lead to a unique experimental data set. Moreover, Large Eddy Simulations are carried out to give a picture of the entire flow field and complement the experimental observations. Additionally, the numerical approach intends to provide a robust methodology that is able to provide high fidelity predictions of the performance of internal cooling channels.

[pt] Os modelos mais populares para solucionar escoamentos turbulentos são baseados no esquema RANS (Reynolds Average Navier Stokes) que necessita de fechamento para relacionar o tensor de tensões de Reynolds com os tensores médios cinemáticos. A solução clássica é a aproximação por Bussinesq que assume uma relação linear entre a parte deviatórica do Tensor de Reynolds e o tensor das taxas de deformação. Trabalhos anteriores mostraram que uma relação não linear entre o tensor das taxas de deformação pode melhorar a predição do modelo. No presente trabalho, primeiramente é realizada uma avaliação entre modelos lineares presentes na literatura seguido de uma análise de três modelos de ordem elevada que expandem a base tensorial para incluir tensores ortogonais. Duas adimensionalizações, uma com a energia cinética turbulenta e taxa de dissipação e outra com energia cinética turbulenta e intensidade do tensor de deformação, haviam sido propostas. As previsões dos modelos são comparados com dados DNS para um canal e para uma gama variada de número de Reynolds. Todos os modelos são implementados na plataforma aberta OpenFoam. Predições razoáveis para a componente cisalhante de todos os modelos foram obtidas quando comparadas com os dados DNS. Entretanto, modelos não lineares provaram superioridade na predição das outras componentes. Também foi observado que o modelo não linearmente dependente do tensor taxa de deformação e o tensor não persistencia das deformações foi o que melhor representou os campos providos por DNS. / [en] The most popular models to solve turbulent flows are based on the Reynolds Average Navier Stokes approach (RANS), which needs closure equations to relate the Reynolds stress tensor to the mean kinematic tensors. The classical approach is the Boussinesq approximation that assumes a linear relation between the deviatoric part of the Reynolds stress tensor, and the rate of strain tensor. Previous works have shown, that the non-linear dependence on the rate of strain tensor can improve the model predictions. At the present work, first an evaluation of linear models available in the literature is performed, followed by the analysis of three higher order methods, that expands the tensorial basis to include other objective orthogonal tensors. Two different nondimensionalization, one with the turbulent kinetic energy and dissipation rate and the other one with turbulent kinetic energy and the intensity of the rate of strain, had also been proposed for the models. The performance of the new models is assessed by comparing their numerical predictions to available channel flow and for a broad range of Reynolds Numbers. All models are implemented in the open source platform OpenFOAM. Reasonable predictions of the Reynolds shear component of all models were obtained when compared with the DNS data. However, the non-linear models proved superior in the prediction of the other components. It was also observed that the model which depends nonlinearly with the rate of strain and linearly with the non-persistence of strain was the one that best represented the DNS data field.

In some species, including humans, red blood cells (RBCs) under low shear stress tend to clump together and form into regular stacks called rouleaux. These stacks are not static, and constantly move and break apart. This phenomenon is referred to as red blood cell aggregation and disaggregation. When modelled as a single liquid, blood behaves as a non-Newtonian fluid. Its viscosity varies, mainly due to the aggregation of RBCs. The aim of this research is to develop a mesoscale computational model for the simulation of RBCs in plasma. This model considers RBC interaction and aggregation to predict blood-flow characteristics such as viscosity, rouleaux size and velocity distribution. In this work, the population-balance modelling (PBM) approach is utilized to model the RBC aggregation process. The PBM approach is a known method that is used for modelling agglomeration and breakage in two-phase flow fluid mechanics to find aggregate size. The PBM model is coupled to the incompressible Navier-Stokes equations for the plasma. Both models are numerically solved simultaneously. The population-balance equation has been used previously in a more restricted form, the Smoluchowski equation, to model blood viscosity, but it has never been fully coupled with the Navier-Stokes equation directly for the numerical modelling of blood flow. This approach results in a comprehensive model which aims to predict RBC aggregate size and their velocities for different flow configurations, as well as their effects on the apparent macro-scale viscosity. The PBM approach does not treat the microscopic physics of aggregation directly but rather uses experimental correlations for aggregation and disaggregation rates to account for the effects of aggregation on the bulk. To find the aggregation rate, a series of experiments on RBC sedimentation due to gravity is designed. In these tests, aggregated RBCs (rouleaux) tend to settle faster than single RBCs and, due to low shear stresses, disaggregation is very low and can be neglected. A high-speed camera is used to acquire video-microscopic pictures of the process. The size of the aggregates and their velocities are extracted using image processing techniques. For image processing, a general Matlab program is developed which can analyze all the images and report the velocity and size distribution of rouleaux. An experimental correlation for disaggregation rate is found using results from a previous steady-state Couette flow experiment. Aggregation and disaggregation rates from these experiments are used to complete the PBM model. Pressure-driven channel flow experiments are then used for the final validation of the model. Comparisons of the apparent viscosity of whole blood in previous experiments show reasonable agreement with the developed model. This model fills a gap between micro-scale and macro-scale treatments and should be more accurate than traditional macro-scale models while being cheaper than direct treatment of RBCs at the micro-scale.

La modélisation des phénomènes physiologiques induits par un écoulement, tels que l'écoulement sanguin au travers d'une sténose ou l'écoulement d'air lors de la production de parole, repose souvent sur des théories quasi-unidimensionnelles ou bi-dimensionnelles. Cependant, il est établi que le développement des couches limites dépend de la section transversale. Le but de cette thèse est de modéliser, simuler et caractériser l'importance potentielle de la section transversale sur les écoulements laminaires, contrôlés en pression, en l'absence ou en présence d'une constriction. Des coordonnées de translation sont utilisées pour obtenir des solutions pour des écoulement visqueux au travers d'une section de forme arbitraire. Cette paramétrisation est appliquée à la résolution des équations physiques pour des formes à deux et à trois dimensions. Un modèle d'écoulement simplifié quasi-tridimensionnel, qui prend en compte les pertes dissipatives par convection, la viscosité et la forme de la section est présenté et appliqué à la description de l'écoulement le long d'une sténose. Des données expérimentales et issues de simulations numériques sont collectées afin de caractériser l'influence de la forme de la section transversale dans le cas d'une constriction. simulation numérique sont comparées. / Physical models of physiological flow-induced phenomena, such as blood flow through a stenosis or air flow during human speech production, often rely on a quasi-one-dimensional or two-dimensional flow model, so that details of the cross section shape are neglected. Nevertheless, boundary layer development is known to depend on the cross section shape. The aim of this thesis is to model, simulate and characterize the potential impact of the cross section shape for pressure-driven laminar channel flow without and with constriction. Stretched coordinates are introduced to obtain viscous flow solutions for channels with an arbitrary cross section. The proposed cross section shape parametrization is applied to solve physical equations for two-dimensional and three-dimensional shapes. A simplified quasi-three-dimensional flow model, which accounts for kinetic losses, viscosity and the cross section shape, is presented and applied to describe the flow through a stenosis. Finally, flow data are gathered experimentally and numerically in order to characterize the influence of the cross section shape in the case of a constricted channel. Modeled, experimental and numerical data are compared.

Flow induced self-oscillations cause acoustic pressure oscillations of large amplitude in pipe flows. If Reynolds number is treated as a parameter, these floinduced oscillations occur only at discrete and critical values of Reynolds number. However, for a small range of Reynolds numbers around such a critical value, such periodic oscillations may appear intermittently. If intermittency, which is a precursor to these self-oscillations, can be detected, prediction of an impending instability may be possible. In experiments done by Vineeth and Sujith (Int. J. Aeroacoustics, 2016) on flow in a duct orifice arrangement, where flow enters through the duct inlet, and leaves into the atmosphere through the orifice exit, “whistling” was observed at a Reynolds number of 4200 (based on the orifice thickness and flow speed within the orifice), where large amplitude pressure oscillations were observed. At slightly lower Reynolds numbers, bursts of relatively smaller amplitudes of pressure oscillations were observed to appear intermittently. For a similar configuration, Large Eddy Simulations (LES) have been carried out with explicit filtering as a sub­ grid scale model here. Both whistling and intermittency are observed in the simulations. As air flows from the duct into the orifice, it turns sharply around the corner at the duct­ orifice interface. Due to this sharp turn, flow separation occurs, and hence, a shear layer is formed at the mouth of the orifice. The mechanism of whistling is found to be this shear layer within the orifice flapping about and hitting the trailing edge of the orifice periodically, thus causing the shear layer to break and roll up into a vortex. At Reynolds numbers where intermittency is observed, the shear layer is found to very mildly come in contact with the edges of the orifice walls, thus disturbing it. In the simulations, time series data of pressure are recorded at various probe locations. In a given time series, if scale invariance behaviour exists, it can be quantified by measuring the Hurst exponent. The numerical value of the Hurst exponent is an index of “long range or short range dependence” in a time series. Hurst exponent is measured in the time series data obtained. It is found to drop to zero as the flow approaches the state of a self-sustained oscillation, since the growth rates of all the long term as well as short term trends in the time series vanish. A loss of multifractality in the time series is also observed as the flow approaches whistling. As a part of the this thesis, new, split high resolution schemes of high order are designed following the Hixon Turmel Proposal.

Les écoulements turbulents de gaz denses, qui sont d’un grand intérêt pour un large éventail d'applications, sont le siège de phénomènes physiques encore peu connus et difficiles à étudier par des approches expérimentale. Dans ce travail, nous étudions pour la première fois l’influence des effets de gaz denses sur la structure de la turbulence compressible à l’aide de simulations numériques. Le fluide considéré est le PP11, un fluorocarbure lourd, dont le comportement thermodynamique a été représenté à l’aide de différentes lois d’état, afin de quantifier la sensibilité des solutions aux choix de modélisation. Nous avons considéré d’abord la décroissance d’une turbulence homogène isotrope compressible. Les fluctuations de température sont négligeables, alors que celles de la vitesse du son sont importantes à cause de leur forte dépendance de la densité. Le comportement particulier de la vitesse du son modifie de manière significative la structure de la turbulence, conduisant à la formation de shocklets de détente. L’analyse de la contribution des différentes structures à la dissipation d’énergie et à la génération d’enstrophie montre que, pour un gaz dense, les régions de forte dilatation jouent un rôle similaire à celles de forte compression, contrairement aux gaz parfaits, dans lesquels le comportement est fortement dissymétrique. Ensuite, nous avons mené des simulations numériques pour une configuration de canal plan en régime supersonique, pour plusieurs valeurs des nombres de Mach et de Reynolds. Les résultats confirment la validité de l’hypothèse de Morkovin. L’introduction d’une loi d’échelle semi-locale prenant en compte le variations de densité et viscosité, permet de comparer les profils des grandeurs turbulentes (contraintes de Reynolds, anisotropie, budgets d’énergie) avec ces observés en gaz parfait. Les variables thermodynamiques, quant à elles, présentent une évolution très différente pour un gaz parfait et pour un gaz dense, la chaleur spécifique élevée de ce dernier conduisant à un découplage des effets dynamiques et thermiques et à un comportement proche de celui d’un fluide incompressible avec des propriétés variables. / Dense gas turbulent flows, of great interest for a wide range of engineering applications, exhibit physical phenomena that are still poorly understood and difficult to reproduce experimentally. In this work, we study for the first time the influence of dense gas effects on the structure of compressible turbulence by means of numerical simulations. The fluid considered is PP11, a heavy fluorocarbon, whose thermodynamic behavior is described by means of different equations of state to quantify the sensitivity of solutions to modelling choices. First, we considered the decay of compressible homogeneous isotropic turbulence. Temperature fluctuations are found to be negligible, whereas those of the speed of sound are large because of the strong dependence on density. The peculiar behavior of the speed of sound significantly modifies the structure of the turbulence, leading to the occurrence of expansion shocklets. The analysis of the contribution of the different structures to energy dissipation and enstrophy generation shows that, for a dense gas, high expansion regions play a role similar to high compression ones, unlike perfect gases, in which the observed behaviour is highly asymmetric. Then, we carried out numerical simulations of a supersonic turbulent channel flow for several values of Mach and Reynolds numbers. The results confirm the validity of the Morkovin' hypothesis. The introduction of a semi-local scaling, taking into account density and viscosity variations across the channel, allow to compare the wall-normal profiles of turbulent quantities (Reynolds stresses, anisotropy, energy budgets) with those observed in ideal gases. Nevertheless, the thermodynamic variables exhibit a different evolution between perfect and dense gases, since the high specific heats of the latter lead to a decoupling of dynamic and thermal effects, and to a behavior close to that of variable property incompressible fluids.

In this dissertation, we are concerned with the numerical simulation for flows of electrically conducting fluids exposed to an external magnetic field (also known as magnetohydrodynamics or in short MHD). The aim of the present dissertation is twofold. First, the in-house CFD hydrodynamic solver SFELES is extended to MHD problems. Second, MHD turbulence is studied in the simple configuration of a MHD pipe flow within an external transverse magnetic field. Chapter 2 of this dissertation aims at reminding the physical equations that govern incompressible MHD problems. Two equivalent formulations are put forward in the particular case of quasi-static MHD. Chapter 3 is devoted to the detailed development of the hybrid spectral - stabilized finite element methods for quasi-static MHD problems. The extension of SFELES is made for both Cartesian and axisymmetric systems of coordinates. The short chapter 4 follows to provide the performances of SFELES executed by several processes in a parallel environment. The addition of a parallel direct solver is studied in regards with the memory and time requirements. The extension of SFELES is then validated in chapter 5 with test cases of increasing complexity. For this purpose, laminar flows with an existing analytical-asymptotic solution are considered. The subject of chapter 6 is the MHD turbulent pipe flow within an external transverse and uniform magnetic field. The results are partially compared with the corresponding hydrodynamic flow and with a few data available in the literature. / Le thème de cette thèse de doctorat est la simulation numérique d'écoulements de fluides conducteurs d'électricité qui sont exposés à un champ magnétique extérieur (également connu sous le nom de magnétohydrodynamique ou encore MHD). L'objectif de ce travail est double. Premièrement, le code CFD maison SFELES est étendu aux problèmes MHD. Deuxièmement, la turbulence MHD est étudiée dans la configuration de l'écoulement en conduite cylindrique à l'intérieur d'un champ magnétique transverse. Le chapitre 2 de cette thèse a pour but de rappeler les équations qui gouvernent les problèmes de MHD incompressible. Deux formulations équivalente sont mises en évidence dans le cas particulier de la MHD quasi-statique. Le chapitre 3 est dévoué au développement détaillé des méthodes spectrale - éléments finis pour la MHD quasi-statique. L'extension de SFELES est réalisée dans les systèmes de coordonnées cartésiennes et axisymétriques. Le court chapitre 4 suit pour fournir les performances de SFELES exécuté sur plusieurs processeurs dans un environnement parallèle. L'ajout d'un solveur parallèle direct est étudié en ce qui concerne les demandes en temps et mémoire. L'extension de SFELES est alors validée dans le chapitre 5 avec des cas d'étude de complexité croissante. Dans ce but, des écoulements laminaires avec solution théorique-asymptotique sont envisagés. Le sujet du chapitre 6 est l'écoulement MHD turbulent en conduite cylindrique à l'intérieur d'un champ magnétique transverse et uniforme. Les résultats sont partiellement comparés avec l'écoulement hydrodynamique correspondant et avec des données disponibles dans la littérature. / Doctorat en Sciences de l'ingénieur / info:eu-repo/semantics/nonPublished

La simulation des grandes échelles (SGE ou LES pour large eddy simulation) commence à être très utilisée dans l’industrie. Par résolution directe des structures turbulents de grande tailles, le calcul LES est capable de calculer le bruit générée par la voilure ou de prédire avec précision le décollement de coin dans une configuration très simplifiée du compresseur. L’un des problèmes les plus importants pour effectuer un calcul LES est de fournir des conditions d’entrée avec des champs turbulents.Pour une approche hybride RANS/LES (RANS pour Reynolds Averaged Navier-Stokes), les conditions d’entrée turbulentes pour un calcul LES sont générées à l’aide des solutions fournies par le calcul RANS en amont. Il existe plusieurs méthodes pour générer les conditions d’entrée pour LES. Elles peuvent principalement être classées en deux catégories : 1) simulation avec pré-calcul ; 2) la méthode de turbulence synthétique. La simulation avec pré-calcul consiste à effectuer un calcul LES indépendant pour générer un champ turbulent comme conditions d’entrée pour alimenter le calcul principal. Cette méthode peut obtenir des turbulences de haute qualité, mais elle augmente considérablement le temps de calcul et le stockage des données. Le champ turbulent généré par la méthode de turbulence synthétique exige une « distance de adaptation », pendante laquelle le champ turbulent devient pleinement développé. L’objectif principal pour améliorer ce genre de méthodes est donc de diminuer cette distance nécessaire.Dans cette thèse, la méthode de vortex, qui est une approche de turbulence synthétique, est présentée et améliorée. A travers des expériences numériques, les paramètres de la méthode de vortex améliorée sont systématiquement optimisés. L’application à l’écoulement en canal plan et à couche limite en plaque plane, montrent que la méthode de vortex améliorée génère de manière efficace pour fournir des conditions d’entrée pour LES. Dans le cas de l’écoulement en canal plan, la distance d’adaptation nécessaire pour le rétablissement de la turbulence est d’environ 6 fois la demi-hauteur du canal. Pour le cas de l’écoulement en plaque plane, cette distance est environ 21 fois l’épaisseur de la couche limite. Enfin, dans le but de qualifier la turbulence obtenue par des calculs LES, nous utilisons les coefficients de dissymétrie des dérivées des fluctuations de vitesse, et, nous les introduisons comme un nouveau critère pour la qualité de LES. / Large eddy simulation is becoming an important numerical tool in industry recently. Resolving large scale turbulent motions directly, LES is capable to compute the aeroacoustic noise generated by the airfoil or to precisely capture the corner separation in a linear compressor cascade. The main challenge to perform a LES calculation is to prescribe a realistic unsteady inflow field. For hybrid RANS/LES approaches, inflow conditions for downstream LES region must be generated from the upstream RANS solutions. There exist several methods to generate inflow conditions for LES. They can mainly be divided into two categories: 1) Precursor simulation; 2) Synthetic turbulence methods. Precursor simulation requires to run a separate calculation to generate a turbulent ow or a database to feed the main computation. This kind of methods can generate high quality turbulence. However, it requires heavy extra computing load. Synthetic turbulence methods consist in generating a fluctuating velocity field, and within a short “adaptation distance”, the field get fully developed. So main goal of synthetic turbulence methods is to decrease the required adaptation distance. The vortex method which is a synthetic turbulence method is presented and improved here. Parameters of the improved vortex method are optimized systematically with a series of calculations in this thesis. Applications on channel and flat-plate flows show that the improved vortex method is effective in generating the LES inflow conditions. The adaptation distance required for turbulence recovery is about 6 times the half channel height for channel flow, and 21 times the boundary-layer thickness (at the inlet of vortex) for at-plate ow. The velocity-derivative skewness is used to qualify the generated turbulence, and is introduced as a new criterion of LES calculation.

It is important for practical and legal reasons that water and sediments in disturbed areas around the mining operation should be controlled. The construction of a well-designed drainage system that controls erosion and thus restores the proper hydraulic function of the surface is one of the most important post-disturbance features which should be done as part of the mining activities. However, even with the best planning and design, unless proper construction practices are adapted; both the disturbed and reclaimed areas are very much likely to be susceptible to erosion, sedimentation and stability problems. In order to tackle the problem, guidelines on how to design and construct the drainage system should be well prepared. The main objective of this study was to prepare guidelines for the proper design, construction and monitoring of the water drainage management system in the study areas (Kankberg, Maurliden and Renström-Petiknäs). This report has analysed the results from the outcome of HEC-RAS software for the case study of the new ditch around the Maurliden mine site and integrated with different guidelines. Based on the results of the HEC-RAS, the most common problems in the drainage system have been identified. Moreover the thesis project identified important physical parameters such as cross-sections and slopes of the representative ditch which affect the function of the ditch in the study areas. Hydraulic parameters such as velocity which is very important for designing the type of lining and also Froude number which is very important in identifying the type of flow whether it is super-critical, critical or sub-critical were identified. The latter helps to select the type of guideline to be used between steep slope and mild slope.

This work presents the development and analysis of a system that combines the concepts of light field microscopy and particle image velocimetry (PIV) to measure three-dimensional velocities within a microvolume. Rectanglar microchannels were fabricated with dimensions on the order of 350-950 micrometers using a photolithographic process and polydimethylsiloxane (PDMS). The flow was seeded with fluorescent particles and pumped through microchannels at Reynolds numbers ranging from 0.016 to 0.028. Flow at Reynolds numbers in the range of 0.02 to 0.03 was seeded with fluorescent particles and pumped through microchannels. A light field microscope with a lateral resolution of 6.25 micrometers and an axial resolution of 15.5 micrometers was designed and built based on the concepts described by Levoy et al. Light field images were captured continuously at a frame rate of 3.9 frames per second using a Canon 5D Mark II DSLR camera. Each image was post processed to render a stack of two-dimensional images. The focal stacks were further post processed using various methods including bandpass filtering, 3D deconvolution, and intensity-based thresholding, to remove effects of diffraction and blurring. Subsequently, a multi-pass, three-dimensional PIV algorithm was used to measure channel velocities. Results from PIV analysis were compared with an analytical solution for fully-developed cases, and with CFD simulations for developing flows. Relative errors for fully-developed flow measurements, within the light field microscope refocusing range, were approximately 5% or less. Overall, the main limitations are the reduction in lateral resolution, and the somewhat low axial resolution. Advantages include the relatively low cost, ease of incorporation into existing micro-PIV systems, simple self-calibration process, and potential for resolving instantaneous three-dimensional velocities in a microvolume.