Tesi sul tema "Water tunnel experiments"

An inverted airfoil mounted above a flat plate was used to create laminar separation bubbles on a flat plate in water tunnel experiments at low Reynolds numbers. Boundary layer suction ensured that the flow remained attached to the wing. Two-dimensional PIV measurements were used to qualitatively and quantitatively characterize the spanwise bubble variation on an unswept wing and on the same wing featuring a 22 degree sweep. The separation bubbles were recorded at varied span-wise locations in a 31.5 cm wide region of the flow. The limitations of this measurement region were dictated by the focal length of the laser optic used for PIV measurements. The straight wing exhibited approximately uniform time averaged separation positions across the span of the wing. The reattachment locations varied only slightly which was expected due to the transition to turbulent flow before reattachment. A form of bubble "breathing" was observed in the laminar separation bubbles on the straight wing and is believed to have affected the mean reattachment locations for two data points recorded. The shedding frequencies on the straight wing were slightly higher than those obtained from CFD simulations. The swept wing planform showed significantly more variation in the mean separation and reattachment locations with respect to the leading edge of the wing. There is a general trend of the separation locations moving upstream in the direction of the aft leading edge. The reattachment points are shown to move downstream as the separation points move upstream relative to the leading edge and visa versa, displaying an inverse relationship between the two. The bubble lengths were found to be slightly longer on the swept wing compared to the straight wing usually by about 10%. The shedding frequencies on the swept wing were found to be lower than the straight wing. The quality of flow in the water tunnel may have degraded over time, showing signs of increased free stream turbulence. After data collection, it was also discovered that the boundary layer suction on the wing was not constant at all span-wise locations. It is believed that the introduction of wing sweep intensified the effect of insufficient suction on the structure of the bubbles observed. The present results were in agreement with previous research for bubble structure but the dynamic instabilities were found to differ slightly.

Dans le cadre des études de sûreté, il est nécessaire de disposer de modèles validés des forces fluides s’exerçant sur des assemblages combustibles en cas de séisme. Dans la technologie REP (réacteur à eau pressurisée) utilisée en France, les assemblages sont constitués de faisceaux de crayons cylindriques disposés en réseau carré et soumis à un écoulement axial. En cas de séisme, ces assemblages sont soumis à des oscillations latérales. Ces vibrations peuvent mener à la déformation des assemblages. Des campagnes d’essais sur assemblage combustible réel ont été réalisées et ont mis en évidence l'existence de forces fluides dissipatives dont l'évolution et la répartition spatiale reste encore mal documentées. L'objectif des présents travaux est de contribuer à la description de ces forces en dynamique. Le modèle de référence pour la description de la dynamique des structures élancées sous écoulement axial est le modèle de TLP (Taylor-Lighthill-Païdoussis). Dans la littérature ce modèle a été validé pour une structure très proche du faisceau de cylindres. Des études statiques réalisées sur un cylindre dans un faisceau ont montré une influence non négligeable des extrémités sur les efforts exercés par le fluide sur la structure. La littérature propose peu de cas de validation du modèle TLP pour des structures plus complexes et proches d'un assemblage combustible. Afin d'évaluer la capacité du modèle à décrire les efforts fluides s'exerçant sur une structure plus proche d'un assemblage combustible, un nouveau banc d'essai a été conçu et mis en service. Ce banc d'essais permet de faire osciller latéralement un faisceau de cylindre 5 x 5 muni de grilles à chaque extrémité dans un écoulement axial. Des mesures de force au niveau de chaque grille donne accès à la résultante d'effort de la structure. Un modèle numérique complète cette approche expérimentale et donne accès à la répartition des efforts dans la structure. Les forces obtenues expérimentalement semble indiquer un effet important des grilles. Les forces issues des simulations confortent les observations faites sur un faisceau de cylindres et apportent de nouveaux éléments sur la répartition des efforts locaux ainsi que l'influence des extrémités
Within the framework of safety studies, it is necessary to have validated models of the fluid forces exerted on fuel assemblies in the event of an earthquake. In the PWR (Pressurized Water Reactor) technology used in France, fuel assemblies are made of cylindrical rods bundles arranged in a square array and subjected to an axial flow. In case of an earthquake, these assemblies are subjected to lateral oscillations. These vibrations can lead to the deformation of the assemblies. Test campaigns on real fuel assemblies have been carried out and have revealed the existence of dissipative fluid forces whose evolution and spatial distribution are still poorly documented. The objective of the present work is to contribute to the description of these forces in dynamics. The reference model for the description of the dynamics of slender structures under axial flow is the TLP model (Taylor-Lighthill-Païdoussis). In the literature this model has been validated for a structure very close to the cylinder bundle. Static studies performed on a cylinder in a bundle have shown a non-negligible influence of the extremities on the forces exerted by the fluid on the structure. The literature proposes few validation cases of the TLP model for more complex structures close to a fuel assembly. In order to evaluate the capacity of the model to describe the fluid forces exerted on a structure closer to a fuel assembly, a new test bench was designed and put into service. This test rig allows to laterally oscillate a cylinder bundle 5 x 5 with grids at each end in an axial flow. Force measurements at each grid give access to the resultant force of the structure. A numerical model completes this experimental approach and gives access to the distribution of forces in the structure. The forces obtained experimentally seem to indicate an important effect of the grids. The forces obtained from the simulations confirm the observations made on a bundle of cylinders and bring new elements on the distribution of the local forces as well as the influence of the extremities

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Neste trabalho realiza-se um estudo do escoamento no interior de um canal com protuberâncias parietais para números de Reynolds menores que 103. Os ensaios foram conduzidos em um túnel hidrodinâmico vertical. Perfis de velocidade na seção de testes, assim como a intensidade turbulenta do túnel e emissões de vórtices, foram adquiridos por meio da anemometria de fio/filme quente. Técnicas de visualização de escoamentos, também, foram empregadas em diferentes circunstâncias, com três objetivos fundamentais: como ferramenta de análise qualitativa, na identificação de padrões de escoamento; como mecanismo de apoio à realização de medidas experimentais, para auxiliar no correto posicionamento de sondas anemométricas; e, finalmente, como instrumento complementar de análise, para facilitar a interpretação de resultados. Em todos os casos o escoamento foi tratado estritamente bidimensional. Outro fator importante deste trabalho refere-se a reconstrução do túnel hidrodinâmico vertical, o qual situa-se no Laboratório de Visualização de Escoamentos do Departamento de Engenharia Mecânica da UNESP - campus de Ilha Solteira; que com grande empenho dos Professores Edson Del Rio Vieira, Sergio Said Mansur, Técnicos do laboratório e com uma pequena contribuição de minha parte pode-se finalizar esse projeto
In the present work is accomplished a study of the flow within a channel with parietal 3 protuberances for Reynolds numbers less than 10 . The tests were conducted in a hydrodynamic tunnel vertical. Velocity profiles in the test section, as well as the turbulent intensity of the tunnel, vortex emissions were acquired through anemometry wire / hot film. Flow visualization techniques were employed as a tool for qualitative analysis, in the identification of flow patterns, as qualitative analytical tool to identify flow patterns; as a mechanism to support the implementation of experimental measurements, to assist in the correct positioning of airspeed probes; and finally as an additional tool of analysis, to facilitate interpretation of results. In every case the disposal was treated dimensional strictly. Another important factor of this work refers to the reconstruction of vertical hydrodynamic tunnel, which is located in the Flow View Laboratory, Department of Mechanical Engineering of UNESP - campus of Single Island; that with great commitment of Teachers Edson Vieira Del Rio, Sergio Said Mansur, lab technicians and a small contribution from me you can finish this project

Orientador: Sérgio Said Mansur
Co-orientador: Edson Del Rio Vieira
Banca: André Luiz Seixlack
Banca: Odenir de Almeida
Resumo: Neste trabalho realiza-se um estudo do escoamento no interior de um canal com protuberâncias parietais para números de Reynolds menores que 103. Os ensaios foram conduzidos em um túnel hidrodinâmico vertical. Perfis de velocidade na seção de testes, assim como a intensidade turbulenta do túnel e emissões de vórtices, foram adquiridos por meio da anemometria de fio/filme quente. Técnicas de visualização de escoamentos, também, foram empregadas em diferentes circunstâncias, com três objetivos fundamentais: como ferramenta de análise qualitativa, na identificação de padrões de escoamento; como mecanismo de apoio à realização de medidas experimentais, para auxiliar no correto posicionamento de sondas anemométricas; e, finalmente, como instrumento complementar de análise, para facilitar a interpretação de resultados. Em todos os casos o escoamento foi tratado estritamente bidimensional. Outro fator importante deste trabalho refere-se a reconstrução do túnel hidrodinâmico vertical, o qual situa-se no Laboratório de Visualização de Escoamentos do Departamento de Engenharia Mecânica da UNESP - campus de Ilha Solteira; que com grande empenho dos Professores Edson Del Rio Vieira, Sergio Said Mansur, Técnicos do laboratório e com uma pequena contribuição de minha parte pode-se finalizar esse projeto
Abstract: In the present work is accomplished a study of the flow within a channel with parietal 3 protuberances for Reynolds numbers less than 10 . The tests were conducted in a hydrodynamic tunnel vertical. Velocity profiles in the test section, as well as the turbulent intensity of the tunnel, vortex emissions were acquired through anemometry wire / hot film. Flow visualization techniques were employed as a tool for qualitative analysis, in the identification of flow patterns, as qualitative analytical tool to identify flow patterns; as a mechanism to support the implementation of experimental measurements, to assist in the correct positioning of airspeed probes; and finally as an additional tool of analysis, to facilitate interpretation of results. In every case the disposal was treated dimensional strictly. Another important factor of this work refers to the reconstruction of vertical hydrodynamic tunnel, which is located in the Flow View Laboratory, Department of Mechanical Engineering of UNESP - campus of Single Island; that with great commitment of Teachers Edson Vieira Del Rio, Sergio Said Mansur, lab technicians and a small contribution from me you can finish this project
Mestre

Road and rail tunnels are important parts of the modern infrastructure. High strength concrete (HSC) is commonly used for tunnels and other civil engineering structures, since it allows high load carrying capacity and long service life. In general, Swedish road and rail tunnels should be designed for a service life of 120 years. However, HSC has shown to be sensitive to severe fires in the moist tunnel environment, i.e., fire spalling may occur. Extensive research shows that addition of polypropylene (PP) fibres in the fresh concrete mix significantly reduces the risk of fire spalling. The durability of a concrete structure is mainly governed by the transport properties. Further, experimental studies aimed at understanding the protective mechanism of PP fibres indicate that fluid transport increases in connection with the melting temperature of such fibres. This might reduce the durability of fire exposed concrete with addition of PP fibres. This study aims to investigate whether the use of PP fibres has any significant effect on the durability of moderate fire exposed concrete structures. The experimental study focused on transport properties related to durability and stiffness reduction of fire exposed civil engineering concrete with and without addition of PP fibres. The study consists of three parts; (i) unilateral fire exposure in accordance with the standard time-temperature curve (Std) and a slow heating curve (SH), (ii) uniformly heating of non-restrained samples to 250oC, and (iii) moderate unilateral fire exposure, 350oC, of restrained samples. Changes in material properties caused by the fire exposure were studied by means of ultrasonic pulse velocity, full field-strain measurements during uniaxial compression core tests, polarization and fluorescence microscopy (PFM), water absorption and non-steady state chloride migration. The study shows that fire exposure influences different properties of importance for load carrying capacity and durability. To get a clear image of the fire damage one has to combine different test methods during damage assessments. Transport properties of concrete both with and without addition of PP fibres were considerably affected even at moderate fire exposure. Hence, the service life might be reduced. All series with addition of PP fibres exhibited higher water absorption compared to the series without PP fibres. The practical importance of this might, however, be small since also the water absorption of concrete without PP fibres was considerably affected for the fire scenarios considered in this study. Behind the fire exposed surface, i.e., between 30 and 60 mm, no change in water absorption was observed for concrete without PP fibres. However, higher water absorption of the series with addition of PP fibres was observed. Indicative fire tests aimed to evaluate the resistance to fire spalling during a subsequent severe fire was also conducted. The concretes with addition of PP fibres showed no signs of fire spalling, while progressive spalling was observed for the concrete without PP fibres.

QC 20150603

Etude en tunnel hydrodynamique de l'influence de la teneur en germes libres de l'eau sur la cavitation se developpant sur un profil bidimensionnel en ecoulement permanent. On etudie le type de cavitation (poche attachee ou bulle separee) et son developpement en fonction de l'incidence du profil, du nombre de reynolds, du parametre de cavitation et de la concentration en germes libres. On determine des zones d'influence des germes. On montre l'importance de la couche limite et du nombre de germes actifs dans la determination du debut de cavitation et du type de cavitation. Application aux machines tournantes

La vélocimétrie par intercorrélation d'images de particules (V. I. I. P. ) a fait l'objet d'un développement complet ayant pour but l'étude d'écoulements dans un tunnel hydrodynamique. Elle consiste en une analyse bidimensionnelle par intercorrélation (corrélation-croisée) de deux images prises simultanément par un capteur CCD standard. Ces images sont obtenues en éclairant, par un plan laser, des particules préalablement ensemencées dans l'écoulement. L'algorithme de corrélation-croisée a été comparé au traitement généralement utilisé : l'autocorrélation, et ceci à l'aide d'un programme générateur d'images simulées. Cette comparaison montre que l'intercorrélation d'images séparées résout à la fois le problème du signe et des mesures de vitesse autour de zéro, cela permet de bénéficier d'une dynamique de vitesse maximum dans la fenêtre d'analyse. Elle met aussi en évidence qu'on peut accepter des densités de particules beaucoup plus élevées et du même ordre que la densité utilisée pour la visualisation par tomographie. Enfin, nous abordons l'application de la méthode aux écoulements dans un tunnel hydrodynamique autour de profils immergés (cylindre, hélice). Nous montrons qu'en dépit d'un ensemencement utilisant des microbulles d'air de différents diamètres et en faible concentration, la V. I. I. P. Permet d'étudier les écoulements propres au tunnel. Dans ce contexte, les informations instantanées, obtenues après l'utilisation de critères de validation de vecteurs vitesse et l'application de post-traitements, permettent ainsi l'analyse de phénomènes de fluctuation spatiale qui apparaissent par exemple dans le sillage d'un cylindre.

When a real fluid flow passes over the surface of a flat plate, the velocity of the fluids on the surface of the object becomes same as that of the object. If object is at rest, the fluid will also have zero velocity because of no slip condition at the boundary. Away from the boundary the velocity increase gradually and reaches to free stream velocity and hence there exists a region closed to the object where velocity gradient exists, this region is known as boundary layer region. The flow in the boundary layer is viscous and rotational. Due to viscous effect shear stress is developed inside the boundary layer, above the boundary layer region the flow is non viscous. Study of boundary layer is vital for design of streamline bodies such as air foil. Generally most of wind tunnel is mainly designed for the study of aeronautic action with laminar flow and produces low depth of boundary layer due to lack of turbulence intensity in test section of wind tunnel. This thesis describes how thick boundary layer can be produced in a short wind tunnel. Several type of thickening (passive) devices are used to increase the boundary layer growth in low speed wind tunnel. This project is a study of four different passive devices (spire, mat, square and diamond blocks) separately and in various combination so that boundary layer can be increased and analyzes the effect of these roughness elements on boundary layer parameter using velocity profile at various free stream velocity at various sections in wind tunnel. This thesis is also used to simulate the atmospheric boundary layer in wind tunnel with a short test section (8m ×.6m×.6m). This project presents the design, computation analysis and experimental study of passive device of different configuration.

碩士
國立臺灣科技大學
機械工程系
98
The purpose of this research is to study the flow fields caused by a round tube jet in a crossflow within the near-wake region. The experiments of a crossflow passing around a cylindrical tube and a round tube jet under different static pressures are observed by using flow visualization and Particle Image Velocimeter (P.I.V.) techniques. Crossflow is produced by a vertical water tunnel, with ReD = 250 1080. The jet is supplied and controlled by pumping water through a rotameter into the cylindrical tube, with Rej = 260 ~ 2200. Experimental observations on crossflow passing around a cylindrical tube are divided into vertical longitudinal and cross sections. Vertical longitudinal section of the flow field is located at Z/D = 0. When ReD increases, the bifurcation line of downwash barely changes, but the region of the lee-side of cylindrical tube close to the tip has some variations. Vertical cross sections of the flow field are located at X/D = 0, -2.5, -5, -10, respectively. At X/D = 0, ambient fluid around the cylindrical tube tends to move toward the center region of the lee-side of cylindrical tube. There is no vortex observed. At X/D = -2.5, there is a stronger shear layer to confine the wake region. Wake tends to move toward the central region of the lee-side of the cylindrical tube. At X/D = -5, low ReD case shows vortices are created periodically and switch between left and right. For high ReD cases, periodical appearing vortices seem to be disturbed by stronger downwash crossflow. At X/D = -10, both high and low ReD cases show vortices appear periodically and interchange between left and right. Wakes move in S-shape pattern. For experiments of various Rej at two different water levels in stationary fluid. When Rej < 1330, jet breakdown position in the high water level is more close to the jet nozzle source, but when Rej > 1330, the comparison results are reversed. When Rej = 1330, jets in the low and the high water levels show a similar breakdown point position.

Flowing behaviour of real fluid is very complex to understand. When real fluid flows over a solid body or a solid plate, the fluid particles adhere to the boundary of the stationary surface and the phenomenon of no slip condition occurs. This results that the velocity of fluid near to the boundary will be same as that of boundary. If the boundary is stationary, the velocity of fluid at the boundary will be zero. The velocity of fluid increases from zero velocity on the stationary boundary to the free stream velocity of the fluid in the direction normal to the boundary .Boundary layer is defined by its parameters as boundary layer thickness, momentum and displacement thickness. In boundary layer region viscous effect is prominent; drag force and shear force act within this layer on the body. Study of boundary layer is important for design of stream line bodies such as air foils. Most wind tunnels, typically designed for the study of aeronautics with smooth laminar flow, lack the turbulence intensity and sufficient boundary layer depths. The present work shows how thick boundary layers can be produced in a wind tunnel with a view to simulate atmospheric flows. The wind loading on structures depends on the velocity and turbulence parameters of the approaching flow. Therefore, in order to obtain similitude between the model loading in the wind tunnel and the real structure, different types of thickening devices are used which are 2.5 cm cube blocks as a floor roughness and 45cm height spires of different configurations in test section. Analysed the effect of different patterns of spires and floor roughness blocks on boundary layer parameter in test section using velocity profiles at variable free stream velocity, were measured at five sections in test section. And roughness parameter was measured for all configurations of spires and blocks using log-law of velocity profiles.This paper summarizes the recent investigations involving the computations of effects of roughness thickness, mainstream velocity and distance from roughness plate on turbulent boundary layer along with the correlations.

碩士
國立臺灣大學
機械工程學研究所
95
In the large underground cables tunnel, the part of the electric energy carried by the cables will dissipate and transform into heat. Therefore, an effective cooling system is demanded to take the heat away for decreasing the air temperature in the tunnel as well as keeping a safe and pleasant environment. In this work a semicircular tunnel were used as the main body to simulate the underground tunnel, within which an electrical heater could generate heat. Four PE water tubes were set to perform indirect water cooling. The air temperature distribution in the tunnel, the temperature change on the water tubes and the heater were all measured and analyzed. Both the non-dimensional variables Nusselt number, Nu, and Rayleigh number, Ra, were also calculated. The effect of the cold water flow rate（8LPM, 12LPM and 16LPM）, number of cold water tube（four and single）, the relative positions of the single heater and cold water tubes, and the surface temperature of the heater（from 100℃ to 250℃）were discussed. The whole study was conducted for the Rayleigh number between 4.41 x 104 and 8.19 x 104. In the experiment of four cold water tubes, the result shows that the larger the flow rate of cold water is, the larger the axial temperature gradient in the front section of the tunnel gets. However, the uniform air temperature in axial direction was obtained when the flow rate of cold water getting smaller. By the temperature distribution profile, a local relative high and low temperature area near the upper-right and lower-right of the semicircular wall of the tunnel can be found. In each cross-section in the axial direction, is maximized and minimized with the water flow rate at 16LPM and 8LPM, respectively, while rises in accordance with the increasing water flow rate. In the study of single heater and cold water tube, the tunnel temperature rises sharply at first and becomes uneven with increasing surface temperature of heater. rises to 5.2x104 from 4.7x104 when the surface temperature of heater is increased from 100℃ to 150℃. However, a large change in Rayleigh number（from 4.7 x 104 to 5.2 x 104） only makes small change in （from 10.1 to 10.3）. If the surface temperature of heater is raised to the range of 200℃ and 250℃, increases obviously. In addition, highest and can be obtained by arranging the cold water tube directly above the heater.

碩士
國立高雄第一科技大學
環境與安全衛生工程研究所
103
An experimental study of tunnel fire with both longitudinal ventilation and water spray systems were conducted in Taiwan. The tunnel was 88 m long , 10 m wide and 8 m high. The fire used was heptane and poured in 1, 4 and 9 m2 fuel pan, Equivalent to 2.5, 10 MW and 25 MW. The ventilation system can produce cross-sectional air flow with velocity of 1.5 m/s or 2.5 m/s. The water spray system can produce distributed water with volume per minute and unit area of 6 L/min∙m2 . Four fire scenarios were applied, free burning, with water spray system, with ventilation system, and with both ventilation and water spray system. The data show that the ventilation system can strongly decreased the temperature and heat flux downstream of fires, and can make a safe environment for evacutee and fire fighters. The water spray system even enhanced the performance of ventilation system. Additionally, the ventilation can reduce the temperature of tunnel structure, although the ceiling temperature downstream of the fires was still high. The water spray system can help decrease the downstream temperature of tunnel structure. Furthermore, the ventilation system can prevent the flame spread through vehicles.

碩士
臺灣大學
機械工程學研究所
98
Natural convection heat transfer in a circular enclosure has been developed for a long time. One of many applications is cooling system of underground cable tunnels. For Taiwan, We lack for experiences of building underground cable tunnels. We need more literatures to provide a lot of information for structuring underground cable tunnels. In underground cable tunnels, a part of electric energy is dissipated by electrical cable so the cooling-water system is needed. In this research the circular tunnel made of concrete was used to simulate underground cable tunnels. Tube-shaped heater was simulated electrical cables. Five pipes made of stainless structured indirect cooling water system. The purpose of this research is to optimize cooling efficiency. The effect of the position of cooling water pipes(A,B,C,D,E), the angle of the heat source(30°,60°,90°,120°), the power of the heat source(1300, 975, and 650 W), the flow rate of the cooling water(4, 8, 12, and 15LPM), the number of the cooling water pipes were discussed. T-type Thermocouples installed on cross section of downstream section of underground cable tunnel to measure air temperature. In the experiment of single pipe of cooling water, the smallest distance between single pipe of cooling water and heater was the highest efficiency but local relative high temperature was higher than any other case. When the position of single pipe of cooling water is fixed, the power of heater didn’t influence the distribution of temperature of air significantly. The average Temperature profile was like a parabolic line when the flow rate of cooling water increased from 4 LPM to 15 LPM and strong fluctuations of temperature of air occurred on the section of entrance of the tunnel as the flow rate of cooling water more than 12 LPM. The level of heat source was lower then the temperature of air was more uniform. In the experiment of number of pipes of cooling water, the result shows that more pipes of cooling water were activity then the temperature of cross section of the tunnel is lower due to increase the total area of cooling water pipes. The best layout is that Multi-pipes are arranged on the top of the tunnel and heater is the same but below the pipes.

The research detailed in this thesis was focused on developing an experimental testing system to characterize the non-dimensional performance coefficients of horizontal axis kinetic turbines, including both wind turbines and tidal turbines. The testing rig was designed for use in a water tunnel with Particle Image Velocimetry (PIV) wake survey equipment to quantify the wake structures. Precision rotor torque measurement and speed control was included, along with the ability to yaw the rotor. The scale of the rotors were purposefully small, to enable rapid-prototyping techniques to be used to produce many different test rotors at low cost to furnish a large experimental dataset. The first part of this work introduces the mechanical design of the testing rig developed for measuring the output power of the scaled rotor models with consideration for the requirements imposed by the PIV wake measurements. The task was to design a rig to fit into an existing water tunnel facility with a cross sectional area of 45 by 45 cm, with a rotor support structure to minimize the flow disturbance while allowing for yawed inflow conditions. A rig with a nominal rotor diameter of 15 cm was designed and built. The size of the rotor was determined by studying the fluid similarities between wind and tidal turbines, and choosing the tip speed ratio as a scaling parameter. In order to maximize the local blade Reynolds number, and to obtain different tip speed ratios, the rig allows a rotational speed in the range of 500 to 1500 RPM with accurate rotor angular position measurements. Rotor torque measurements enable rotor mechanical power to be calculated from simulation results. Additionally, it is included in this section a description of the instrumentation for measurement and the data acquisition system. It was known from the outset that measurements obtained in the experiments would be subject to error due to blockage effects inherent to bounded testing facilities. Thus, the second part of this work was dedicated to developing a novel Computational Fluid Dynamics (CFD) methodology to post-process the experimental data acquired. This approach utilizes the velocity field data at the rotor plane obtained from the water tunnel PIV test data, and CFD simulations based on the actuator disk concept to account for blockage without the requirement for thrust data which would have been unreliable at the low forces encountered in the tests. Finally, the third part of this work describes the practical aspects of the laboratory project, including a description of the operational conditions for turbine testing. A set of preliminary measurements and results are presented, followed by conclusions and recommendations for future work. Unfortunately, the water tunnel PIV system was broken and thus unavailable for more than a year, so only mechanical measurements were possible with the rig during the course of this thesis work.
Graduate