[en] In this thesis, Soret, thermodiffusion and diffusion coefficients of several binary and ternary mixtures have been determined. In addition, thermophysical and optical properties such as density, thermal expansion, mass expansion, dynamic viscosity, refractive index and contrast factor such as derivatives of the refractive index as a function of temperature and concentration have been obtained. One of the mixtures that has been analyzed is composed by Toluene‐Methanol‐Cyclohexane. These mixtures correspond to the second phase of DCMIX project. We have studied 26 binary mixtures of this system. This analysis has been carried out by Prof. Köhler's group of Universität Bayreuth from Germany and Prof. Shevtsova's group of Université Libre de Bruxelles from Belgium. This work, has allowed to frame the ternary parameter space by thoroughly investigating the boundaries along the binary composition lines. Correlations for the thermophysical properties have been included in this study. By means of Thermogravitational Column, Slidding Symmetric Tubes, Optical Beam Deflection and Optical Digital Interferometry techniques, it has also been obtained Soret, thermodiffusion and diffusion. Additionally, we have determined the diffusion coefficients of Toluene‐Methanol‐Cyclohexane of a ternary mixture by Slidding Symmetric Tubes technique. In the third phase of DCMIX project, the thermodiffusion coefficient of Triethylene Glycol‐Water‐Ethanol system has been determined. In total, 12 binary mixtures and 2 ternary mixtures have been analyzed. Moreover, we have determined the Soret coefficient of ternary mixtures composed by Methylnaphthalene‐Toluene‐nDecane. The diffusion coefficients have been measured by Slidding Symmetric Tubes technique and the thermodiffusion coefficients were measured previously in Fluid Mechanic groups. Lastly, we have applied the Digital Interferometry analysis method to the thermogravitational micro‐column. By this method, the entire concentration distribution in the height of the column has been determined. Besides, the installation is equipped by two different wavelength laser in order to ternary mixtures under the hermogravitational effect using optical analysis method.

[eu] Tesi honetan, hainbat nahasketa bitar eta hirutarren Soret, termodifusio eta difusio garraio propietateak neurtu dira. Horrekin batera, zenbait propietate termofisiko nahiz optiko ere neurtu dira, esaterako, dentsitatea, espantsio termikoa, espantsio masikoa, biskositate dinamikoa, errefrakzio indizea eta kontraste faktore deritzon, errefrakzio indizearen aldaketa tenperatura eta kontzentrazioaren arabera. Aztertutako nahasketen artean, DCMIX proiektuko bigarren faseko Toluenoa‐Metanola‐Ziklohexanoa osagaiak daude. Guztira, 26 nahasketa bitar aztertu dira Alemaniako Universität Bayreuth‐ko Prof. Köhler eta Belgikako Université Libre de Bruxelles‐ko Prof. Shevtsovaren taldeekin elkarlanean. Lan honetako hainbat nahasketa bitarren azterketak, nahasketa hirutarrak kokatzea ahalbidetu du. Horretarako, literaturako datuekin eta lan honetako neurketekin, propietate termofisikoen doikuntzak aurkeztu dira. Guztira, lau teknika esperimental erabili dira, Columna Termogravitacional, Slidding Symmetric Tubes, Optical Beam Deflection eta Optical Digital Interferometry. Bestalde, Toluenoa‐Metanola‐Ziklohexanoa osagaiez osatutako nahasketa hirutar baten difusio koefizienteak neurtu dira Slidding Symmetric Tubes teknikaren erabiliz. Aztertutako bigarren nahasketa, DCMIX proiektuko hirugarren fasean aztertzen diren Trietilene Glikola‐Ura‐Etanola osagaiez osaturik dago. Guztira, 12 nahasketa bitarren eta 2 nahasketa hirutarren termodifusio koefizienteak neurtu dira. Horretaz gain, Metilnaftalenoa‐Toluenoa‐nDekanoa osagaiez osatutako nahasketa hirutarraren difusio koefizienteak ere neurtu dira. Lan honetan neurtu diren difusio koefizienteei eta Fluido Mekanikako departamentuan lehenago neurtutako termodifusio koefizienteei esker, nahasketa hauen Soret koefiziente neurtu ahal izan da. Azkenik, Digital Interferometry analisi metodoa aplikatu zaio mikro‐zutabe termograbitazionalari. Analisi metodo honen bitartez, mikro‐zutabearen altuera osoko kontzentrazio distribuzioa aztertu ahal izan da. Gainera, instalazio honetan uhin luzera desberdineko bi laser erabiltzen direnez, nahasketa hirutarrak aztertzea ahalbidetzen du optikan oinarritutako analisi metodoen bidez.