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This diploma thesis deals with rheological properties of mayonnaise. The theoretical part of the thesis deals with the characterization of mayonnaise and the emulsion that mayonnaise represents, it deals with production of mayonnaise, components and storage too. Another issue is about rheological properties of foods and effects that affect them. The practical part deals with evaluation of analytical indicators, such as pH, titration acidity, fat content and dry matter and rheological properties. The aim of this thesis is to determine what type of fluid mayonnaise represents. The viscosity of samples was measured by a rotary viscometer at increasing shear rate and subsequently at constant shear rate for 300 seconds. Flow curves were created from these data, they represent dependence of shear stress on shear rate, which indicate that mayonnaise is a non-Newtonian fluid that have plastic and pseudoplastic behavior. Dependence of viscosity on time were created, it indicates that mayonnaise have thixotropic behavior. Control and adjustment of rheological properties such as viscosity provide a quality product.

The combination of traditional passive acoustic liners with Herschel-Quincke (HQ) waveguides is proposed in this work as a device for Turbofan Engine Noise Control. The approach consists of installing circumferential arrays of HQ tubes on the lined sector of the inlet of a turbofan engine. A theoretical model is developed to predict the performance of this system assuming that the engine inlet is a circular lined duct with uniform mean flow. The tube-duct interfaces are modeled as finite piston sources that couple the sound field inside the duct with the dynamics of the HQ tubes. The finite piston source radiation is modeled in terms of a new closed form Green's function, which is found as the solution of the non-homogeneous convected acoustic wave equation with soft wall boundary conditions. The Green's function is extended from a point source to a finite piston by using the Divergence Theorem in the appropriate form. The dynamics of the HQ tube are both modeled as plane waves inside a straight tube and experimentally determined. The experimental determination of the HQ-dynamics is undertaken using impedance tubes with a 4-microphone technique. The newly developed theoretical model was used to predict the performance of a combined HQ-Liner system, which was tested on a scale simulated turbofan rig. The model is validated for broadband noise with the experimental data obtained from this test rig. The analytical predictions are shown to correlate well with experimental data. The results of the application of a HQ-Liner on a turbofan engine show a great potential in order to improve the performance of traditional passive acoustic liners. / Ph. D.

Commercial aviation transportation has experienced an overwhelming growth over the years. However, this expansion has encountered an important barrier: noise. Several studies have shown that residents in these areas experience problems such as stress and sleep disturbance. These problems have translated into demands for a better quality of life from airport residents which in turn have translated into more stringent aircraft noise regulations. As a result, large amounts of resources have been diverted towards the improvement of existing noise attenuation technologies and the development of more effective ones. In terms of turbofan generated noise, the most widely used technology is that of absorbent materials or liners. In recent investigations Alonso et al. have combined Herschel/Quincke (HQ) tubes with liners. This combination has the potential of effectively controlling pure tones and broadband noise in inlet sections of modern turbofan engines. Since a comprehensive approach for engine noise reduction will involve both inlet and aft HQ-Liner systems, additional research efforts were needed to evaluate their performance at reducing aft fan radiation In the present work, a combination of traditional liners and Herschel/Quincke waveguide resonators for aft fan radiation control is proposed. A theoretical model is developed in order to predict noise reduction due to such systems. The newly developed tool was then utilized to design an HQ-liner that was installed and tested in the aft section of the NASA Active Noise Control Fan (ANCF) rig. This experimental data was utilized to prove the potential of these systems and to validate the mathematical model. Analytical predictions correlate well with experiments. The NASA ANCF rig is not representative of a real turbofan engine. In order to assess the behavior of HQ-Liners in a more realistic environment a new system was specifically designed for a generic turbofan engine and its performance analyzed. The sound field inside HQ tubes has been described assuming plane waves only. This assumption limits the model to frequencies below the tube first resonance. In order to overcome this limitation a new model accounting for higher order modes inside the tubes has been developed. / Ph. D.

An innovative implementation of the Herschel-Quincke tubes concept for the reduction of noise from turbofan engines is proposed here. The approach consists of installing circumferential arrays of Herschel-Quincke (HQ) tubes or waveguides in the inlet of the turbofan engine. An analytical technique was developed to predict the effects of HQ tubes applied to circular inlets. The modeling technique involves modeling the tubes-inlet interfaces as finite piston sources that couple the acoustic field inside the inlet with the acoustic field within the HQ tubes. An optimization technique based on genetic algorithms was also developed to be able to design and optimize the system parameters. The accuracy of the model was validated with experimental data obtained from two types of turbofan engines. Analytical predictions are shown to correlate well with experimental data. The analytical model is then used to provide insight into the noise control mechanisms involved in the system. It is shown that the energy in an incident mode is in part reflected back to the fan and that some energy is also scattered into other higher-order modes. Thus, the suppression of a particular mode is due to the combination of the scattered contributions from the various incident modes. The effects of the system parameters were analyzed and parametric studies were conducted. Different configurations for the arrays of HQ tubes such as helical patterns or tubes at an angle with respect to the inlet axis were also investigated. The results show the great potential of the HQ tubes system to reduce noise from turbofan engines. / Master of Science

A fundamental study of the Herschel-Quincke (HQ) tube concept for the reduction of noise in circular ducts is presented here. Recent testing of the Herschel-Quincke tube concept on the Pratt-Whitney JT15D and AlliedSignal TFE731-60 engines showed the potential for the practical application of this approach. A model of the HQ-system has been developed to aid in the design of the system tested. The model has revealed new noise control mechanisms associated to the implementation of multiple HQ-waveguides in a duct in the presence of higher order modes. However, the practical nature of these engine facilities results in limitations with regard to the fundamental research knowledge that could be gained from testing in a more controlled laboratory environment. A series of experiments was conducted at the NASA Langley Research Center 0.30 m ducted fan test facility where detailed modal measurements were performed. The main goals of this research endeavor were to evaluate the accuracy of the previously developed theoretical model and provide insight into the noise control mechanisms. Experiments were performed with different disturbance mode structures, number of HQ tubes and arrays, and axial positions. The modes in the duct were generated with an array of acoustic drivers (no flow case) and measured with logarithmically spaced circumferential and helical microphone arrays located on the duct wall. The modal amplitudes of the incident, transmitted, and reflected modes in the duct were determined from the microphone measurements. This allowed for the comparison of analytical and experimental modal amplitudes, modal powers, total power, and reductions. The results of this study provide insight into the three noise control mechanisms associated with this approach: reflection, circumferential scattering, and radial scattering. Comparison with the experimental results shows that the model accurately predicts the sound power attenuation except near the cut-off frequency of the modes where it tends to overestimate the attenuation. The effect of the number of tubes in the array and its axial position was also evaluated. Overall, the results of this study validate the general modeling approach for the HQ tube concept. / Master of Science

Ma thèse s'inscrit dans l'étude de la physique extragalactique. Pendant mes trois années de thèse j'ai travaillé sur les méthodes d'ajustement de la distribution d'énergie spectrale des galaxies (ou SED fitting) en effectuant un bilan énergétique entre l'émission en ultraviolet et l'émission en infrarouge. A cet effet j'ai très largement utilisé le code CIGALE (Burgarella et al. 2005, Noll et al. 2009) qui permet d'estimer les paramètres physiques des galaxies à partir de l'analyse de leur émission dans des bandes larges et intermédiares de l'ultraviolet au submillimétrique. J'ai procédé pendant ma thèse à des améliorations de ce code en rajoutant des paramètres d'extinction en sortie et j'ai implémenté plusieurs modèles d'émission de noyaux actifs de galaxies pour compléter les modèles existants.En parallèle de l'étude de la méthode de SED fitting avec des données en bandes larges et intermédiaires, j'ai développé la construction originale d'un catalogue de galaxies artificielles, dont le but est de déterminer la fiabilité des paramètres de sortie du code CIGALE et des codes de SED fitting en général. La technique du SED fitting m'a permis d'analyser plusieurs échantillons de galaxies dans l'univers proche et dans l'univers lointain possédant des données multi longueurs d'onde. Pratiquement j'ai travaillé avec des données allant de l'ultraviolet (GALEX) à l'infrarouge lointain avec les téléscopes spatiaux AKARI et Herschel. Les données AKARI couplées à des données ancillaires ont été à la base d'une étude de galaxies de l'univers local pour lesquelles j'ai pu déterminer la quantité d'atténuation.J'ai également travaillé avec les données Herschel en tant que membre des consortiums HerMES et GOODS-H. Dans le cadre du projet GOODS-H j'ai participé à la mise en évidence et à l'étude du "bump" à 2175 A d'un échantillon de galaxies distantes ainsi qu'à la formulation d'une loi d'atténuation pour ces objets. Dans le cadre d'un groupe de travail sur le SED fitting au sein d'HerMES j'ai participé à l'étude d'un échantillon de galaxies avec 0<z<3 afin de déterminer la fiabilité des paramètres physiques estimés par différents codes de SED fitting.Une partie de ma thèse a été consacrée à l'étude de galaxies distantes et lumineuses en infrarouge et à la détermination des caractéristiques physiques de ces objets grâce au code CIGALE. L'étude des paramètres de formation stellaire et d'atténuation ont fait l'objet d'un article, Giovannoli et al. (2011) paru dans la revue scientifique A&A. Toujours dans le cadre du projet HerMES j'ai pu avoir accès aux données du télescope spatial Herschel pour ces objets et donc poursuivre mon étude afin de déterminer l'importance des données infrarouges et submillimétriques pour l'étude des galaxies à haut redshift. / My PhD thesis takes part of extragalactic physics. During three years I have worked on the fit of the spectral energy distribution (SED fitting) of galaxies by doing an energetic budget between the emission at ultraviolet wavelengths and the one at infrared wavelengths. I have extensively used the code CIGALE (Burgarella et al. 2005, Noll et al. 2009) allowing to estimate the physical parameters of galaxies from their broad bands and intermediate bands emission from ultraviolet wavelengths to submillimetric wavelengths. During my thesis I have improved this code by adding output parameters and several templates of active galactic nuclei to those already available.While I have studied the SED fitting technics I have also built original mock catalogues of galaxies to determine the reliability of the output parameters of CIGALE and, more generally, the reliability of parameters estimated by SED fitting codes.I have used the SED fitting method to analyse several samples of galaxies from low redshift to high redshift, with multi wavelength detections. I have used data from the ultraviolet (GALEX) to the far infrared using data from AKARI and Herschel space observatory. I have matched the AKARI data to ancillary data at other wavelengths to study nearby galaxies and determine their dust attenuation quantity. I have used Herschel data as part of HerMES and GOODS-H consortium members. In the framework of the GOODS-H project I have worked on the determination and the study of the so-called ultraviolet bump at 2175 A for a sample of high-redshift galaxies, and on the formulation of an attenuation law for these objects. In the framework of HerMES I have worked with the SED fitting working group to study a sample of galaxies with 0<z<3 to determine the reliability of the physical parameters of these objects estimated with differents SED fitting codes.A part of my thesis was devoted to the study of a sample of distant galaxies, luminous at infrared wavelengths. I have determined the physical parameters of these objects thanks to the code CIGALE. The study of the star formation parameters and the attenuation parameters has been published in Giovannoli et al. (2011), in the scientific journal A&A. With the HerMES project I could have access to Herschel data for these luminous galaxies and pursue my study to determine the importance of far infrared data to study high-redshift galaxies.determine the importance of far infrared data to study high-z galaxies.

Les modèles et les observations actuels de l’Univers sont en accords aux grandes échelles. Néanmoins, cela ne permet pas d’expliquer la formation des structures baryoniques dans l’Univers. Afin de contraindre la formation des structures dans l’Univers, des observations sont nécessaires à différents redshifts pour observer les structures à différentes étapes d’évolutions. Le satellite Planck donne accès à des objets dont les redshifts sont compris entre z=2 et z=4. Ainsi environ 1200 objets extragalactiques susceptibles d’être à haut redshift sont détectés dans 26% du ciel, autour des pôles galactiques. Un sous échantillon de 228 sources est observé à plus grande sensibilité et résolution angulaire avec le satellite Herschel. Grâce à ces observations je peux résoudre les sources ponctuelles de Planck en plusieurs sources Herschel. J’identifie alors trois possibilités de type de sources, soit c’est une candidate de source amplifiée par lentillage gravitationnel, soit c’est un candidat d’amas de galaxies à haut redshift, soit c’est un alignement de sources fortuit le long de la ligne de visé. Après analyse, j’ai identifié dans cet échantillon 11 sources amplifiées par lentillage gravitationnel parmi les plus brillantes du ciel sub-millimétrique. Ces sources ont des redshifts compris entre z=2.2 et z=3.6 (Canameras et al., 2015) et permettent de sonder la formation stellaire dans l’Univers lointain. Il reste 217 surdensités de sources que j’ai étudié. En utilisant la couleur des sources Herschel, j’ai calculé une estimation de la densité des sources. 50% des champs Herschel de l’échantillon on une surdensité supérieur à 10sigma lorsque l’on sélectionne les sources rouges (S250/S350 < 1.4 et S500/S350 > 0.6). Cela montre que l’échantillon est principalement composé de surdensité de source rouge. En ajustant un corps noir modifié à 35K sur les données photométrique Herschel-SPIRE je montre que la distribution de redshift photométrique des sources piquent à z=2. Notre échantillon se compose donc de 11 sources lentillées et 217 potentiels amas de galaxies à redshift z~2. Ces potentiels amas de galaxies se compose d’en moyenne 9 sources dans 4.5’ de diamètre. Les sources individuelles ont des luminosités infrarouges d’environ 4.1012 Lsol ce qui correspond d’après Bell et al. 2003 à un taux de formation stellaire (SFR) de 700 Msol.yr-1. Cela mène pour les potentielles structures à une luminosité de 4.1013 Msol et un SFR de 7000 Msol.yr-1. Notre échantillon trace donc les structures denses du ciel à fort taux de formation stellaire. Cet échantillon sera donc clé dans la compréhension de la formation des structures et des étoiles à des redshifts autour de z=2. / Actual models and observations of the Universe agreed at large scale. But the formation of baryonic structures remains unknown. To constrain structure formation in the Universe, observatoins are needed at different redshift to see different evolution steps. Planck satellite gives an acces to objetcs in the redshift range z=2 to z=4. Thus we detect about 1200 extragalactic objects in 26% of the sky near galactic poles, candidates to be at high redshift. A sample of 228 sources is observed at higher sensibility and resolution than Planck with Herschel satellite. This lead to resolve ponctual Planck sources in several Herschel sources. So I identify three possible types of object : candidates sources of gravitationally amplified lenses, galaxy cluster candidates and alignement of sources along the line of sight. I find in the sample 11 sources amplified by gravitationnal lensing, some of the brightest of the submillimeter sky. Those have redshift between z=2.2 and z=3.6 (Canameras et al., 2015) and provide a zoom in the stellar formation of the far Universe. It let 217 overdensity of sources that I study. With their colour in Herschel data, I find an estimate of their density. 50% of Herschel fields have an overdensity greater than 10sigma using red sources colour selection (S250/S350 < 1.4 et S500/S350 > 0.6). This show that our ample is mainly composed of red overdensity. Fitting Herschel-SPIRE photometry with a modify black body at 35K, I show that the photmetric redshift distribution of Herschel sources peaks around z=2. Our sample is now composed of 11 lensed sources and 217 galaxy cluster candidates at z~2. These galaxy cluster candidates contain an average of 9 SPIRE sources in 4.5’ diameter beam. Individual sources have a luminosity distribution peaking at 4.1012 Lsun which leads to a star formation rate (SFR) of 700 Msun.yr-1 (Bell et al. 2003). This gives an estimate structure luminosity of 4.1013 Msun and an SFR of 7000 Msun.yr-1 assuming that sources are members of the same structure. Our sample traces dense structure at high star formation rate in the full sky. This sample will be a key in the comprehension of structure formation and star formation at redshift about z=2.

Le fond extragalactique est le rayonnement relique issu de tous les processus de formation des structures dans l'Univers. Environ la moitié de ce fond, appelé fond infrarouge est émis dans l'intervalle 8-1000 microns, a un maximum d'émission autour de 150 microns, et est essentiellement dû aux processus de formation d'étoiles dans l'Univers. En effet, la luminosité infrarouge d'une galaxie est fortement liée à la formation d'étoiles en son sein. Pour bien comprendre l'origine du fond infrarouge, il faut donc également déterminer l'évolution des galaxies infrarouges.Une mesure statistique relativement simple permettant de comprendre l'origine du fond infrarouge, mais également l'évolution des galaxies, consiste à compter les sources en fonction de leur flux. J'ai mesuré les comptages de sources infrarouges dans les données des télescopes spatiaux Spitzer et Herschel, ainsi que celles de l'expérience BLAST, en utilisant des méthodes variées. Les sources détectées individuellement dans les cartes Spitzer à 24 microns émettent la majeure partie du fond. En revanche, à plus grande longueur d'onde, la sensibilité et la résolution angulaire des instruments décroît. Les sources détectées n'expliquent alors plus qu'une petite partie du fond. L'analyse par empilement (ou stacking) permet de mesurer le flux moyen infrarouge lointain ou sub-millimétrique d'une population détectée uniquement dans l'infrarouge moyen. Cette technique fournit des limites inférieures contraignantes sur la valeur du fond à grande longueur d'onde, mais permet également de compter les sources trop faibles pour être détectées individuellement. Ces résultats sont confirmés grâce à l'analyse dite P(D), qui permet de déterminer les comptages directement à partir de l'histogramme d'une carte infrarouge.Ces nouvelles contraintes permettent de préciser le scénario d'évolution des galaxies infrarouges. J'ai construit un modèle paramétrique d'évolution de ces objets permettant d'interpréter les comptages. Ce modèle reproduit de manière satisfaisant les propriétés statistiques de galaxies infrarouges de 15 microns à 1.1 mm. Il prédit que dans l'Univers jeune (z>2), la formation d'étoile a eu lieu majoritairement dans des galaxies ultra-lumineuses en infrarouges (LIR>10^12 luminosités solaires). Ces galaxies formaient des étoiles à un rythme très intense (plus de 100 masses solaires par ans) et n'ont que très peu d'équivalent dans l'Univers local. Depuis, le taux de formation d'étoiles a diminué d'un facteur 10, et la formation d'étoiles a aujourd'hui majoritairement lieu dans des galaxies semblables à la notre. Ce modèle d'évolution a par la suite été utilisé pour interpréter les fluctuations du fond infrarouge à grande longueur d'onde observées par BLAST, Planck et Herschel. / The extragalactic background light is the relic emission of the process of structure formation in the Universe. About half of this background, called cosmic infrared background, is emitted in the 8-1000 microns interval, peaks near 150 microns, and is essentially due to the star formation processes in the Universe. In fact, the infrared luminosity of a galaxy is linked to the hosted star formation. It is thus necessary to determine the evolution of infrared galaxies to well understand the origin of the cosmic infrared background.A rather simple statistical measurement, enabling to understand the origin of the cosmic infrared background, but also the evolution of the galaxies, consist in counting the sources as a function of their flux. I measured number counts of infrared galaxies using different methods in the data of the Spitzer and Herschel space telescopes, and of the BLAST experiment. The individually detected sources in the 24 microns Spitzer maps are responsible of the main part of the background. But, at larger wavelength, the sensitivity and the angular resolution of the instruments decreases, and the detected sources explain only a small part of the background. The stacking analysis enable to measure the mean far-infrared or sub-millimeter flux of a population detected only in the mid-infrared. This technique provides stringent lower limits on the level of the background, but also enables to count the sources which are too faint to be detected individually. These results are confirmed by the P(D) analysis, which determines the counts from the histogram of the infrared maps.These new measurements constrain the evolution of the infrared galaxies. I built a parametric evolution model to interpret the source counts. This model well reproduces the statistical properties of the infrared galaxies between 15 and 1100 microns. It predicts that the star formation in the young Universe (z>2) mainly happen in ultra-luminous infrared galaxies (LIR> 10^12 Lsun). These galaxies formed stars very quickly (more than 100 Msun/years), and have few equivalents in the local Universe. Nowadays, the star formation rate has decreased by a factor of ten, and the star formation mainly happen in galaxies like ours. This model has been used to interpret the fluctuations of the cosmic infrared background at large wavelength observed by BLAST, Planck, and Herschel.