This thesis deals with centrifugal pump impeller design for given parameters. This pump impeller design consists of the calculation of basic dimensions, the meridional flow channel design and blade design. Complete design of the pump impeller is afterwards simulated in CFD programme.

This thesis is concerned with the topic of Pumps with crew centrifugal impeller. Thanks to the benefits such as free passage and efficiency there are many practical applications of these products. Despite this fact there is only few manufacturers dealing with them what results in lack of research and available information in the area. In order to fill the gap, this thesis aims to propose hydraulic of screw centrifugal impeller to the specified parameters. The impeller with a single moving blade will be designed for pumping heavily polluted water and hardly pumpable liquids. Blade will be balanced together with the rotor, while the emphasis will be placed on the highest free passage of impeller. The theoretical part of the thesis summarizes literature on the subject, practical part deals with the calculations and adjustments pointing to a concrete proposal. Parameters of designed hydraulics were verified using stationary calculations using MRF model in FLUENT. As a results, two possible solutions are offered.

En lämplig pumpanordning är avgörande för hantering av stora mängder vatten. I det här arbetet kommer fokus ligga på pumpar som består av öppna pumphjul. Vid montering av pumpen bildas en spalt mellan insatsring och pumphjul, som bör ligga inom intervallet 0,5–0,8 mm för optimal effekt. Beroende på toleranskedjor i pumpens ingående komponenter varierar denna spalt mellan olika fall. Spalten justeras idag genom trimbrickor som placeras under insatsringen. Processen kallas för trimning och kräver en mer tidseffektiv lösning eftersom dagens lösning bygger på metoden ”trial and error”. Målet med projektet var således att konstruera ett universalverktyg i syfte att effektivisera trimningsprocessen tidsmässigt. Vidare var målet att även testa verktygets funktionalitet genom en 3D prototyp. Projektet avgränsades i sin tur till att inte undersöka alternativa trimningsmetoder, designändringar på pumpen, tillverkningskostnader samt materialval. Arbetet startades genom ett produktionsbesök i syfte att öka förståelsen kring problemet samt det aktuella pumpsortimentet. Vidare undersöktes bland annat befintliga mätverktyg, standardkomponenter samt relevant antropometri. Dessutom analyserades diverse funktioner och behov som verktyget behövde uppfylla. Därefter påbörjades idegenereringsarbetet främst genom brainstorming, varvid ett koncept valdes för vidareutveckling. Det slutgiltiga resultatet är ett universalverktyg som går att tillämpa på samtliga pumpar i sortimentet för att effektivisera trimningsprocessen. / A suitable pumping device is essential for handling large quantities of water. This study focuses on pumps consisting of open impellers. When installing the pump, a gap is formed between the insert ring and impeller. This gap should be within the range of 0.5–0.8 mm for optimal effect. Depending on tolerance chains in the pump's constituent components, this gap varies between different cases. Currently, the gap is adjusted using trim washers that are placed beneath the insert ring. The process is called trimming and requires a more time efficient solution since the current solution is based on a "trail and error" method. Therefore, the objective of the project was to construct a universal tool with the aim of streamlining the trimming process in terms of time. Additionally, the goal was to test the tool's functionality through a 3D prototype. In turn, the project was limited to not investigating alternative trimming methods, design changes to the pump, manufacturing costs and material selection. The work was commenced through a production visit with the aim of increasing comprehension of the problem and the current pump range. Furthermore, an examination of existing measuring tools, standard components and relevant anthropometry was carried out. In addition, various functions and needs that the tool required to fulfill were analyzed. Thereafter, the idea generation work began mainly through brainstorming, whereby a concept was chosen for further development. The result of the project is a universal tool that can be applied to all pumps in the range to streamline the trimming process.

The Two-Element In Series (TEIS) and Two-Zone models have been used successfully for over twenty years to model test data for radial flow compressors and pumps. The models can also be used to predict the performance of new machines provided that the model inputs can be accurately specified. Unfortunately, use of the TEIS and Two-Zone models as a predictive tool has been limited because an accurate and broadly applicable method of predicting the modeling parameters, etaA, etaB, chi and d2p does not exist. Empirical models have been developed to predict the TEIS and Two-Zone modeling parameters based on a large database of centrifugal pump and compressor test results. These test data were provided by ConceptsNREC and have been collected over the past 40 years. The database consists of a wide range of machines including some that were designed and tested by ConceptsNREC and others from the open literature. Only cases with a vaneless diffuser or volute have been included in the analysis to avoid any possible impeller-diffuser interactions. From the database, models for all of the TEIS and Two-Zone parameters have been derived using basic regression techniques. Three different models are proposed for each of the two TEIS modeling parameters, etaA and etaB. One model for pumps, another for compressors, and a combined model applicable for all machines is given. For the Two-zone parameters, chi and d2p, a single set of models was developed to represent the design point performance and another showing how chi and d2p vary off-design. The combined models for etaA and EtaB are 30% and 70% more accurate than the current state-of-the-art models, respectively. The new models account for the variance in chi and d2p at off-design flow conditions and further refine the accuracy of the overall prediction by correctly modeling the loss mechanisms in the impeller passage. Validation work has shown that the set of models that predict etaA, etaB, chi and d2p can be solved to consistently produce sensible results and yield a reasonable "blind" prediction of the performance of a wide range of radial compressors and pumps. These models constitute the first broadly applicable method for predicting the required TEIS and Two-Zone variables and are sufficiently accurate to provide initial performance estimates of new impeller designs

No description available.

O presente trabalho teve como objetivo avaliar a influência da intensidade de agitação e tipo de impelidor, bem como a estratégia de alimentação, em reator anaeróbio operado em batelada seqüencial, escala piloto (\'da ordem de\' 1 \'M POT.3\'), com agitação mecânica e em duas configurações: uma com biomassa granulada (ASBR) e outra com biomassa imobilizada em suporte inerte de espuma de poliuretano (ASBBR), aplicadas ao tratamento de esgoto doméstico. No estudo da intensidade de agitação e tipo de impelidor, para cada reator foram avaliadas três tipos de impelidores (turbina de pás planas, turbina de pás inclinadas 45º e hélice) associados a duas intensidades de agitação (40 e 80 rpm), obtendo uma combinação de 6 (seis) condições experimentais. A combinação da intensidade de agitação e tipo de impelidor que apresentou melhor desempenho no processo foi utilizado no estudo da estratégia de alimentação, na qual foi avaliada as seguintes condições: batelada alimentada durante 25%, 50%, 75% e 100% do ciclo. Os resultados obtidos permitiram concluir que: no ASBBR o aumento da intensidade de agitação de 40 rpm para 80 rpm permitiu uma melhoria nos fluxos de transferência de massa e, portanto, aumentou a velocidade de consumo de substrato; no ASBR o aumento da intensidade de agitação de 40 rpm para 80 rpm proporcinou uma desestabilização do sistema, provavelmente por causa da ruptura dos grânulos provocada pela maior agitação; os sistemas operados com impelidor do tipo hélice apresentaram vantagens, tais como: melhor eficiência de remoção de sólidos, maior valor da constante cinética de primeira ordem (melhor fluxo de transferência de massa e conseqüentemente maior consumo de substrato) e maior produção de alcalinidade, ou seja, maior estabilidade para o sistema; tanto o sistema ASBR como o ASBBR quando operados nas condições de batelada típica, batelada alimentada durante 50% e 75% do ciclo apresentaram melhores desempenhos no processo de tratamento, mostrando a flexibilidade operacional dos reatores anaeróbios operados em bateladas seqüenciais; e comparando os sistemas ASBBR e ASBR verificou-se que estes apresentaram comportamentos similares em todas as condições de operação de batelada alimentada avaliadas, não sendo possível, estatisticamente apontar um sistema com melhor desempenho. / The objective of this work was to assess the effect of the stirring speed, the type of impeller and the feed strategy in a mechanically stirred pilot-scale (\'da ordem de\' 1 \'M POT.3\') anaerobic sequencing batch reactor to two configurations: a containing granulated biomass (ASBR) and the other containing immobilized biomass (AnSBBR). Domestic wastewater was treated in 8-h cycles. Three impeller types (turbine with six-flat blades, turbine with six 45º-inclined blades and helix with three blades) were assessed at two different stirring speeds (40 and 80 rpm), totaling six experimental conditions. The stirring speed and the impeller that resulted in the best combination was used in work of the feed strategy . The reactors were operated at room temperature at four different feed strategies (fed batch during 25%, 50% and 75% of the cycle, and conventional fed-batch). The results allowed conclude that: in the AnSBBR increasing the stirring speed from 40 rpm to 80 rpm showed to improve mass transfer, with consequent increase in substrate consumption; in the ASBR increasing the stirring speed from 40 rpm to 80 rpm showed desestabilization in system, because of the disruption caused in the granules witth greater agitation; operation with the helix impeller showed some advantages over the turbine impellers, such as: improved efficiency in solids removal, higher value of the first order kinetic constant and higher alkalinity production; both for the ASBR as for the ASBBR the best performance in wastewater treatment was obtained when the reactors were operated at conventional batch, fed-batch during 50% and 75% of the cycle; no significant difference in performance was observed among these three conditions. Despite poor performance of the conventional fed-batch and fed-batch during 25% of the cycle compared to the other conditions, both these conditions presented operational stability. Hence, the anaerobic sequencing batch reactors presented operational flexibility as far as feed strategy is concerned.

Examensarbetet går ut på att frambringa några principkonstruktioner till axialfläktar med fasta inställbara skovlar åt FläktWoods. Fläktarna det rör sig om är stora industrifläktar med en diameter mellan en och fem meter, som används för att till exempel transportera ner luft i gruvor. Endast förslag till principkonstruktioner tas fram och ej en färdig produkt, syftet med rapporten är i första hand att ge FläktWoods konstruktörer ett annat synsätt på problemet. Två olika delar av fläkten undersöks, dels fästet av skoveln på hjulet, dels själva hjulet i sig. Tillvägagångssättet är att från formulerat problem tas först några förslag fram, de utvärderas sedan och de bästa går vidare till nästa steg. Utvärderingen sker med hjälp av produktförslagsdiagram samt genom diskussion med berörda parter. Efter det ritas några detaljerade versioner av de bästa förslagen upp, vilka sedan är grunden för kraftanalyserna. Analyserna visar var de högsta spänningarna befinner sig och var den svaga länken i konstruktionen är. Avgränsningar inom arbetet är att endast en statisk dragkraft appliceras på modellerna under analyserna och ej någon dynamisk kraft. Ytterligare en avgränsning är att vid kraft/spänningsanalyserna undersöks endast en del av fläkten, som motsvarar ett fläktblad som är fäst vid en rigid del av ringen. Resultatet visar att det endast är i några få punkter och områden som kraftansträngningen blir för höga i principkonstruktionerna för det valda materialet. / The diploma work is about producing some construction proposal for axial fans with fixed adjustable blades for FläktWoods. They are large industrial fans with a diameter between one and five meters. Which is used to, among other things, transport air to mines and for the cooling in power plants. It’s only some proposal that shall be produced and not a finished product, the purpose is mainly about giving the design engineers at FläktWoods a new way to look at the problem. There are two different parts that are under consideration, the way the blade is mounted to the impeller and the construction off a new impeller. The course of action is to from the discussion of the problem produce some proposals that will be evaluated, the best of the proposals will go on to the next step. The evaluation will be done with help of an assessment of solution variants and through discussions with the concerned parties. The next step is to produce some models with more details of the best proposals, this models will be the foundation for the force/stress analysis. The analysis shows where the highest stresses are located and where the weakest part of the proposals. Delimitations within the diploma work is that only a static force will be used during the analysis, and no dynamic force. Another delimitation is that during the force/stress analysis only a part of the fan will be examined, that corresponds to one fan blade that is mounted to a rigid part of the impeller. The result shows that there is only a few point and areas where the forces/stresses are to large in the proposals, for the used material.

<p>Examensarbetet går ut på att frambringa några principkonstruktioner till axialfläktar med fasta inställbara skovlar åt</p><p>FläktWoods. Fläktarna det rör sig om är stora industrifläktar med en diameter mellan en och fem meter, som används för att</p><p>till exempel transportera ner luft i gruvor. Endast förslag till principkonstruktioner tas fram och ej en färdig produkt, syftet</p><p>med rapporten är i första hand att ge FläktWoods konstruktörer ett annat synsätt på problemet. Två olika delar av fläkten</p><p>undersöks, dels fästet av skoveln på hjulet, dels själva hjulet i sig. Tillvägagångssättet är att från formulerat problem tas</p><p>först några förslag fram, de utvärderas sedan och de bästa går vidare till nästa steg. Utvärderingen sker med hjälp av</p><p>produktförslagsdiagram samt genom diskussion med berörda parter. Efter det ritas några detaljerade versioner av de bästa</p><p>förslagen upp, vilka sedan är grunden för kraftanalyserna. Analyserna visar var de högsta spänningarna befinner sig och var</p><p>den svaga länken i konstruktionen är.</p><p>Avgränsningar inom arbetet är att endast en statisk dragkraft appliceras på modellerna under analyserna och ej någon</p><p>dynamisk kraft. Ytterligare en avgränsning är att vid kraft/spänningsanalyserna undersöks endast en del av fläkten, som</p><p>motsvarar ett fläktblad som är fäst vid en rigid del av ringen.</p><p>Resultatet visar att det endast är i några få punkter och områden som kraftansträngningen blir för höga i</p><p>principkonstruktionerna för det valda materialet.</p> / <p>The diploma work is about producing some construction proposal for axial fans with fixed adjustable blades for</p><p>FläktWoods. They are large industrial fans with a diameter between one and five meters. Which is used to, among other</p><p>things, transport air to mines and for the cooling in power plants. It’s only some proposal that shall be produced and not a</p><p>finished product, the purpose is mainly about giving the design engineers at FläktWoods a new way to look at the problem.</p><p>There are two different parts that are under consideration, the way the blade is mounted to the impeller and the construction</p><p>off a new impeller. The course of action is to from the discussion of the problem produce some proposals that will be</p><p>evaluated, the best of the proposals will go on to the next step.</p><p>The evaluation will be done with help of an assessment of solution variants and through discussions with the concerned</p><p>parties. The next step is to produce some models with more details of the best proposals, this models will be the foundation</p><p>for the force/stress analysis. The analysis shows where the highest stresses are located and where the weakest part of the</p><p>proposals.</p><p>Delimitations within the diploma work is that only a static force will be used during the analysis, and no dynamic force.</p><p>Another delimitation is that during the force/stress analysis only a part of the fan will be examined, that corresponds to one</p><p>fan blade that is mounted to a rigid part of the impeller.</p><p>The result shows that there is only a few point and areas where the forces/stresses are to large in the proposals, for the used</p><p>material.</p>

The petroleum fuels are nonrenewable, are finites resources and its combustion produces many pollutants into the atmosphere. So, researches aiming alternative sources of energy have been increased. Vegetable oils seem to be a great alternative to produce biodiesel - a renewable fuel, non-toxic and releases fewer pollutants. The sunflower is a great oilseed for biodiesel production, because it can be planted in northeastern of Brazil during the rainy season. Biodiesel can be obtained by transesterification: reaction between vegetable and/or animal fat with shot chain alcohol in presence of catalyst. The aim of this work is to study the effect of the process variable in the production of biodiesel – agitation speed - and even equipment configuration, as characteristic impeller and presence or absence of chicanery in the reactor. For this, full factorial design 2 ³ was performed a resulting in eight experiments. The biodiesel was produced by the transesterification reaction from refined sunflower oil and anhydrous ethanol, and sodium hydroxide P.A. as catalyst. The following operating conditions were used: temperature of the thermostatic bath maintained at 70 °C; weight of catalyst of 1.5% by weight of oil; ratio between number of moles of oil ans ethanol of 1:10; and reaction time of 30 min. Prior to reaction, was performed to characterize the oil, as well as the characterization of biodiesel obtained after the reaction. It was observed that the presence of baffle contributed to obtain lower yields throughout the reaction. When used impeller 2 (turbine impeller with dimensions greater than those reported in the literature), higher yields were obtained at the beginning of the reaction. The stirring speed of 35o rpm contributed to higher yields were obtained at the beginning of the reaction. / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Os combustíveis derivados do petróleo são não-renováveis, são fontes finitas e sua combustão emite muitos poluentes para a atmosfera. Com isso, têm aumentado as pesquisas por fontes alternativas de energia. Os óleos vegetais parecem ser uma ótima alternativa para obtenção de biodiesel - um combustível renovável, não-tóxico e que libera menos poluentes. O girassol é uma oleaginosa com potencial utilização para produção de biodiesel, podendo ser plantada no Nordeste brasileiro no período chuvoso. O biodiesel pode ser obtido através da transesterificação: reação entre gordura vegetal e/ou animal com álcool de cadeia curta, na presença de catalisador. O objetivo do presente trabalho é estudar o efeito da variável de processo na produção do biodiesel – velocidade de agitação - e ainda configuração do equipamento, como: característica do impelidor e presença ou não de chicana no reator. Para isso, foi realizado um planejamento fatorial completo 2³, resultando em 8 experimentos. O biodiesel foi produzido por reação de transesterificação a partir de óleo de girassol refinado e etanol anidro, tendo-se hidróxido de sódio P.A. como catalisador. Foram utilizadas as seguintes condições operacionais: temperatura de reação de 70 ºC; relação entre a massa de catalisador e a massa do óleo de 1,5%; relação entre número de mols óleo/álcool etílico de 1:10; e, tempo total de reação de 30 min. Previamente à reação, foi realizada a caracterização do óleo, bem como, a caracterização do biodiesel obtido após a reação. Foi observado que a presença de chicana contribuiu para a obtenção de menores rendimentos durante toda a reação. Ao ser utilizado o impelidor 2 (impelidor tipo turbina com dimensões maiores que aquelas citadas na literatura) foram obtidos rendimentos mais elevados no início da reação. A velocidade de agitação de 350 rpm contribuiu para que fossem obtidos maiores rendimentos no início da reação.

Cette thèse est dédiée à l’étude de l’effet de la configuration des agitateurs (pales planes) et la nature du tensioactif sur la dispersion de gaz dans un liquide en vue d’obtenir un produit foisonné. Cette étude est menée à deux échelles pilote et locale. Le premier chapitre est dédié à une étude à l’échelle pilote. Les résultats ont montré qu’à conditions opératoires fixées, lorsque les agitateurs sont collés et décalés, l’aspect distributif de la dispersion de gaz est amélioré. L’aspect dispersif (taille des bulles), en revanche, reste peu sensible à la configuration des agitateurs. Les protéines sériques« WPI » comme agent tensioactif améliore l’efficacité de la rétention de gaz alors que le Tween 20 la réduit et provoque l’augmentation de la taille des bulles. Le deuxième chapitre concerne une approche locale qualitative (observation optique) et quantitative (détermination de capillaire critique). L’étude qualitative a montré que l’ajout d’un angle de décalage modifie l’écoulement du liquide et les bulles suivent la trajectoire imposée par le liquide. Lorsque les protéines WPI est utilisé comme agent tensioactif, sous l’action de la contrainte de cisaillement, les bulles subissent une déformation qui se termine par une rupture par extrémité. Un système couette a permis de déterminer un nombre capillaire critique correspondant à cette rupture. Par contre, en présence du Tween 20, la déformation ne conduit jamais à une rupture par extrémité. Le troisième chapitre de ce travail est dédié à une étude numérique de l’hydrodynamique de l’écoulement. Cette étude a permis de confirmer les résultats obtenus par l’approche qualitative. A titre d’exemple, un décalage entre deux agitateurs collés conduit à la multiplication des zones de vortex, à l’apparition des élongations supplémentaires et d’effet venturi favorables à l’aspect distributif de la dispersion. L’étude numérique montre également que le gradient maximal et moyen de vitesse reste indépendant de la configuration, ce qui explique pourquoi la taille moyenne est indépendante de la configuration. / Flat-blad impellers configuration coupled with tensioactif agents have been used to study gas dispersion in foaming process. The work has been conducted at pilot and local scales. The first chapter is devoted to a study at the pilot scale. The results showed that under a given operating conditions, a shift between two glued successive impellers promotes distributive aspect of the gas dispersion. However the dispersive aspect (bubble size), remains independent of the impellers configuration. The pilot-scale experiments have also shown that the "WPI" enhance foaming efficiency, while, Tween 20 reduces it and increases the size of the bubbles. The second chapter links with a qualitative (optical observation) and quantitative (determination of critical capillary) at local scale. It has been observed that shifted-impellers modify the flow pattern and promotes the distributive aspect of the mixture. When the WPI is used as a surfactant, shear stress induces bubble deformation until a tip-breakup occurs. Using a Couette system, it has been shown that there exist a critical capillary number corresponding to this rupture. However, the deformation does never induced tip-breakup when using Tween 20. The third chapter of this work is devoted to a numerical study of liquid hydrodynamics under different configuration. It appears that the configuration where the impellers are glued and shifted induces the multiplication of the vortex, the appearance of additional elongations and venturi effect. These effects seem to improve the distributive aspect of mixing in agreement with the results obtained previously. The numerical study also shows that the maximum and average shear gradient is independent of the configuration. This result explains why the mean bubble size remains independent of the configuration.