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This thesis provides a comparison of experimental rotordynamic coefficients for laminar, smooth bushing oil seals to theoretical predictions from XLLubeGT and XLAnSeal. The experimental results come from a new test rig developed at the Turbomachinery Laboratory at Texas A&M University. The two software programs were developed to predict the static and dynamic characteristics of seals. XLLubeGT is a Reynolds equation based program while XLAnSeal is based on a bulk-flow Navier- Stokes model that includes temporal and convective acceleration terms. XLAnSeal was used to predict the added-mass terms of the seals since XLLubeGT assumes those terms to be zero or negligible. The data used for input into the two seals code was the actual measured conditions from the test rig. As part of the input parameters, inlet inertia effects and thermal gradients along the seal were included. Both XLLubeGT and XLAnSeal have the capability to analyze straight bore seals with different inlet and outlet clearances – essentially a tapered seal – but seal expansion caused by the radial differential pressure across the seal bushing was not included. Theoretical and experimentally determined dynamic characteristics include stiffness, damping, inertia terms and Whirl Frequency Ratio (WFR). Seal static characteristics are also reported. They include: leakage, shaft center line loci and Reynolds numbers. Test conditions include three shaft speeds: 4000, 7000 and 10,000 rpm, three test pressures: 21, 45 and 69 bar [300, 650, and 1000 psi] and multiple eccentricities from 0.0 to 0.7. The results for the dynamic characteristics show good correlation of the experimental data to the theoretical values up to an eccentricity of about 0.5. At higher eccentricities, the theory generally under-predicts the dynamic characteristics. Inertia terms are greatly under-predicted. The results for the static characteristics also show good correlation to the experimental data, but they also have a tendency to be under-predicted at higher eccentricities.

Extensive experimental data is available from previous research into the behaviour of buoyant jets released into an unstratified ambient. The experimental data has been the basis for theoretical and numerical modelling work, and currently several numerical models exist that are employed in the design of engineering structures built for the disposal of wastewater in the ocean. However there are still flow configurations with limited or no available experimental data, and hence confidence in the use of the models under some circumstances is limited. These circumstances include two-dimensional trajectory flows that are discharged at oblique angles to the ambient and buoyant jet flows with three-dimensional trajectories. As part of the current project an experimental investigation is conducted into the behaviour of discharges that have either two-dimensional or three-dimensional trajectories, focussing particularly on those configurations with currently limited available experimental data. A light attenuation technique is developed for the investigation of such flows, largely because it enables the behaviour of discharges with three-dimensional trajectories to be recorded with relative ease. However, this technique provides integrated views of the flow and hence the interpretation of the integrated concentration data is aided by assumed mean cross-sectional concentration profiles. In the strongly advected region (with the exception of the weak-jet) a double-Gaussian approximation is shown to provide a reasonable representation of mean concentration profiles. In the weakly advected regions and the weak-jet region, it is well- known that a single Gaussian adequately represents the mean flow structure. A new numerical model, the Momentum Model, is developed to assist in the design and to monitor the performance of the experimental investigation. Unlike other models, the behaviour of the flow is determined by the relative magnitudes of the initial excess momentum flux, the buoyancy-generated momentum flux and the entrained ambient momentum flux. It is shown that ratios of these momentum fluxes are equivalent to the length-scales traditionally employed for this task. Predictions from the Momentum Model are compared with data from the current and previous experimental investigations and, in addition, predictions from two representative numerical models, VisJet and CorJet. Predictions from the Momentum Model are shown to be consistent with data for a wide variety of discharge configurations. These predictions are also generally consistent with those of VisJet and CorJet. However, the experimental results from the II buoyant jet discharged in a moving ambient show that the spreading rates of the strongly advected flows (puffs and thermals) differ, and while this difference is incorporated into the Momentum Model, it is not evident in the VisJet and CorJet predictions. Numerical model predictions of negatively buoyant discharges are shown to be inadequate. This discharge configuration is investigated in some detail experimentally and additional analytical solutions of the flow behaviour are developed to aid in the interpretation of the flow behaviour. The experimental results show that buoyancy-induced instabilities on the inner side of the jets, which generate additional vertical mixing, significantly alter the form of the mean concentration profiles in this region. This results in considerably higher integrated dilutions along the flow centreline. Another significant difference between the newly developed Momentum Model and the existing numerical models (VisJet and CorJet), is the approach taken to dealing with oblique discharges in a cross-flow. Experimental results in combination with additional analytical solutions show that for initial discharge angles of 20° and less, an oblique discharge in a cross-flow becomes a weak-jet in the strongly advected region, and for angles of 40° and above, the flow becomes a puff. The strongly advected behaviour predicted by the Momentum Model changes abruptly at the transition angle, and is reasonably consistent with the data. The gradual change in strongly advected behaviour employed by VisJet and CorJet does not appear to be appropriate in the puff region. Finally a preliminary experimental investigation of discharges with three-dimensional trajectories shows that there are significant discrepancies between the predicted behaviour and the experimental data. This is surprising given the numerical models are, for the most part, able to predict the behaviour of flows with two-dimensional paths with reasonable accuracy. It is evident that flows with three-dimensional paths are modified more severely by the different directions of the initial, buoyancy-generated, and entrained ambient momentum fluxes than the current models suggest.

Made available in DSpace on 2014-10-09T12:52:13Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:55Z (GMT). No. of bitstreams: 0 / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

Made available in DSpace on 2014-10-09T12:52:13Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:55Z (GMT). No. of bitstreams: 0 / Um método de cromatografia líquida de alta eficiência por fase reversa (RP-HPLC) para análise qualitativa e quantitativa do hormônio folículo estimulante humano íntegro (hFSH), foi estabelecido e validado quanto à exatidão, precisão e sensibilidade. O FSH humano é um hormônio glicoprotéico dimérico largamente utilizado em medicina reprodutiva tanto para diagnóstico quanto para terapia. A metodologia desenvolvida preserva a integridade da proteína, permitindo a análise da forma heterodimérica intacta, e não somente de suas subunidades, como é normalmente obtida na maioria das condições geralmente empregadas. Esta técnica foi também utilizada para a comparação da hidrofobicidade relativa de preparações de hFSH hipofisária, urinária e derivadas de células de ovário de hamster chinês (CHO) bem como de outros dois hormônios glicoprotéicos, sintetizados na hipófise anterior: hormônio humano estimulante da tireóide (hTSH) e hormônio luteinizante humano (hLH). O menos hidrofóbico dos três hormônios analisados foi o hFSH, seguido do hTSH e do hLH. Uma diferença significativa (p<0,005) foi observada entre o tempo de retenção (tR) das preparações hipofisária e recombinante de hFSH, refletindo diferenças estruturais nas suas cadeias de carboidratos. Duas isoformas principais foram detectadas no hFSH urinário, incluindo uma forma que foi significativamente diferente (p<0,005) das preparações hipofisária e recombinante. Foram demonstradas linearidade da curva dose-resposta (r=0,9965, n=15) para esta metodologia de RP-HPLC, bem como uma precisão inter-ensaio, cujo coeficiente de variação é menor que 4%, para a quantificação de diferentes preparações de hFSH e uma sensibilidade da ordem de 40 ng. Foram também analisados o comportamento cromatográfico e a hidrofobicidade relativa das subunidades individuais das preparações recombinantes e hipofisária de hFSH. Além disso, a exata massa molecular das subunidades individuais de hFSH e do heterodímero foram simultaneamente determinadas por espectrometria de massa MALDI-TOF. A presente metodologia representa, em nossa opinião, uma ferramenta essencial para a caracterização e controle de qualidade deste hormônio, que ainda não consta das principais farmacopéias. / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

Orientador: Liliane Maria Ferrareso Lona / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-11T08:06:10Z (GMT). No. of bitstreams: 1 Belincanta_Juliana_D.pdf: 4082238 bytes, checksum: 20349198a1d8e13a5e2eddcf8d16e5ba (MD5) Previous issue date: 2008 / Resumo: A polimerização viva/controlada é uma área que vem se desenvolvendo rapidamente no escopo de polímeros e engenharia. A habilidade para preparar copolímeros bem definidos do tipo bloco, estrela, redes poliméricas, bem como outros materiais pelo mecanismo da polimerização via radical livre é talvez a principal razão para o crescente interesse pela academia cientifica e meio industrial neste tipo de polimerização viva/controlada. O interesse industrial se deve a aplicabilidade desta nova técnica em áreas como colas, adesivos, surfactantes, dispersantes, lubrificantes, gel, aditivos, elastômeros termoplásticos, bem como aplicações nas áreas de eletrônica e biomedicina. Vale citar a produção industrial de dispersantes pela polimerização mediada por nitróxidos, um caso de polimerização viva/controlada. Este trabalho tem como objetivo investigar experimentalmente e por modelagem a polimerização em massa via radical livre mediada por TEMPO (2,2,6,6-tetramethyl piperidinyl-1-oxy) de estireno e estireno com divinilbenzeno, sob diversas condições experimentais. Para o caso de homopolimerização foi avaliada uma análise de sensibilidade de como as constantes cinéticas afetam o desempenho do modelo. Reações, não incluídas no modelo original, foram adicionadas ao modelo e testadas. O efeito de diferentes concentrações de TEMPO foi avaliado experimentalmente. Foi observado que esta condição afeta significativamente os resultados. Para o caso de copolimerização, resultados experimentais foram obtidos em diversas temperaturas, e concentração inicial de DVB (divinilbenzeno) e TEMPO. O gel obtido pela polimerização mediada por TEMPO apresenta diferenças marcantes daquele preparado pelo sistema convencional, com relação ao perfil de conversão de monômero. O ponto gel para este caso novo foi obtido em tempos maiores daquele obtido em sistemas convencionais. A versatilidade da polimerização mediada por nitróxidos permite a síntese de um número significativo de novas arquiteturas poliméricas. Espera-se que o modelo proposto, bem como os dados experimentais obtidos neste trabalho, seja útil para um melhor conhecimento desta nova técnica de polimerização. Palavras-chave: polimerização viva/controlada, TEMPO, polimerização em massa, experimental, modelagem / Abstract: Controlled/living radical polymerization (CLRP) is one of the most rapidly developing areas of polymer science and engineering. The ability to prepare well-defined block and graft copolymers, gradient and periodic copolymers, stars, combs, polymer networks, end-functional polymers and many other materials by free-radical mechanisms is perhaps the main reason for the increased academic and industrial interest in CLRP. The industrial interest is triggered by the potential of CLRP in areas as coatings, adhesives, surfactants, dispersants, lubricants, gels, additives, thermoplastic elastomers as well as many electronic and biomedical applications. It is pointed out the industrial production of dispersants by nitroxide-mediated radical polymerization (NMRP), one case of CLRP. This study focus on the model and experimental investigation of TEMPO (2,2,6,6-tetramethyl piperidinyl-1-oxy) mediated free radical polymerization of styrene and styrene-co-divinylbenzene carried out in bulk under different experimental conditions. For homopolymerization case, a sensitivity analyses of how kinetic constants affect the model performance was carried out. Other reactions, not included in the previous model, were included and tested. The effect of different initial concentration of TEMPO was evaluated experimentally. It was shown that this condition affects significantly the results. For copolymerization case, experimental results were obtained for different temperature, and initial concentration of DVB and TEMPO. The gel prepared by NMRP showed remarkable differences from the one prepared in the conventional system, in regard to the monomer conversion profile. The gel point was delayed for the new process compared with conventional systems. The versatility of NMRP permits the synthesis of a number of novel architectures. In conclusion, the model proposed is expected to provide useful guidelines towards a better understanding of the NMRP process. Keywords: controlled/living polymerization, TEMPO, bulk polymerization, experimental, model / Doutorado / Desenvolvimento de Processos Químicos / Doutor em Engenharia Química

In this dissertation, experimental data was used to investigate the influence of a nearby mast structure on the striking distance to a lightning rod. The results of this research helped identify and understand the impact of different factors such as stroke polarity, lightning rod height, striking distance to the ground, lateral distance from the lightning stroke to an adjacent mast, and height of the adjacent mast on the striking distance of a lightning rod. Moreover, a system identification methodology was employed for the development and validation of striking distance models from experimental work performed at the Mississippi State University High Voltage Laboratory. Striking distance models were obtained to represent the striking distance to the ground, striking distance to an isolated lightning rod, and striking distance to a lightning rod in the presence of an adjacent mast. In the case of the striking distance to the ground the system identification approach was used for the extraction of the parameters of the black-box model proposed. From the results the relationship between the striking distance to ground and the leader voltage were obtained for both polarities of the lightning stroke. The system identification approach was then expanded to obtain the models for the striking distance to the lightning rod. The system identification approach was used to evaluate different mathematical models based on the ones found in the literature. The models were trained on experimental data, their quality evaluated, and the best model was selected for both positive and negative polarity. Furthermore, the model for negative polarity was evaluated against data from real lightning conditions in order to corroborate the model extrapolation capability. Building on the success obtained on the cases of the striking distance to the ground and to an isolated lightning rod the focus was turned to expanding the models to incorporate the influence of an adjacent mast. Models for positive and negative polarity were obtained and the quality of the equations was evaluated.

The project was aimed at describing the mixing phenomena relevant for both safety analysis, particularly in steam line break and boron dilution scenarios, and mixing phenomena of interest for economical operation and the structural integrity. Measurement data from a set of mixing experiments, gained by using advanced measurement techniques with enhanced resolution in time and space help to improve the basic understanding of turbulent mixing and to provide data for Computational Fluid Dynamics (CFD) code validation. Slug mixing tests simulating the start-up of the first main circulation pump are performed with two 1:5 scaled facilities: The Rossendorf coolant mixing model ROCOM and the VATTENFALL test facility, modelling a German Konvoi type and a Westinghouse type three-loop PWR, respectively. Additional data on slug mixing in a VVER-1000 type reactor gained at a 1:5 scaled metal mock-up at EDO Gidropress are provided. Experimental results on mixing of fluids with density differences obtained at ROCOM and the FORTUM PTS test facility are made available. Concerning mixing phenomena of interest for operational issues and thermal fatigue, flow distribution data available from commissioning tests (Sizewell-B for PWRs, Loviisa and Paks for VVERs) are used together with the data from the ROCOM facility as a basis for the flow distribution studies. The test matrix on flow distribution and steady state mixing performed at ROCOM comprises experiments with various combinations of running pumps and various mass flow rates in the working loops. Computational fluid dynamics calculations are accomplished for selected experiments with two different CFD codes (CFX-5, FLUENT). Best practice guidelines (BPG) are applied in all CFD work when choosing computational grid, time step, turbulence models, modelling of internal geometry, boundary conditions, numerical schemes and convergence criteria. The BPG contain a set of systematic procedures for quantifying and reducing numerical errors. The knowledge of these numerical errors is a prerequisite for the proper judgement of model errors. The strategy of code validation based on the BPG and a matrix of CFD code validation calculations have been elaborated. Besides of the benchmark cases, additional experiments were calculated by new partners and observers, joining the project later. Based on the "best practice solutions", conclusions on the applicability of CFD for turbulent mixing problems in PWR were drawn and recommendations on CFD modelling were given. The high importance of proper grid generation was outlined. In general, second order discretization schemes should be used to minimise numerical diffusion. First order schemes can provide physically wrong results. With optimised "production meshes" reasonable results were obtained, but due to the complex geometry of the flow domains, no fully grid independent solutions were achieved. Therefore, with respect to turbulence models, no final conclusions can be given. However, first order turbulence models like K-e or SST K-w are suitable for momentum driven slug mixing. For buoyancy driven mixing (PTS scenarios), Reynolds stress models provide better results.

Made available in DSpace on 2014-10-09T12:43:24Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:56:10Z (GMT). No. of bitstreams: 1 06526.pdf: 11749564 bytes, checksum: 3bdf9fe6bde542868235ac958c48f4f4 (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP