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The influence of decreasing of impeller diameter, change Q - Y characteristic
Hyriak, Maroš ; Habán, Vladimír (referee) ; Haluza, Miloslav (advisor)
The purpose of the thesis is to familiarize with the fundamental characteristics of ta centrifugal pump while changing geometry of the output section of its impeller trimming. Characteristics of a pump is calculated whilst diameter of the impeller is changed. More specifically, changes in the flow and energy are observed while diameter of the impeller is decreasing. Two possible solutions, approximate and accurate, are offered for both parameters. The thesis suggests that an application of the approximate solution is satisfactory for the flow calculation of the impeller. In contrast, for the energy calculation is the approximate solution sufficient only in case of the slight trimming. Increase in the trimming results in the drop of the hydraulic efficiency and decrease in the accuracy of the results. Consequently, the accurate solution is recommended for the energy calculations. Limitations of the paper may be represented by two facts. First, in comparison with the calculations, results are in reality affected my numerous variables that have not been included in the calculations due to their unpredictability. Second, calculations were based on the several assumptions that are rarely met in the reality. The results of the thesis are applicable in the every-day life when adapting the pump to the customer needs.
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Comparison of modal properties of steam turbine impeller with blades of different lengths
Havlásek, Michal ; Chromek, Lukáš (referee) ; Lošák, Petr (advisor)
The presented master's thesis deals with the safety assessment of several variants of the impeller with different blades length. The motivation for creating this thesis is to find the solution of the problem situation which is characterized by the breakdown of the steam turbine impeller with blades length of 30mm. As confirmed in this thesis, the impeller with blades length of 30mm is operated in the resonance. Likewise, according to the technical standard ČSN EN ISO 10437 its operation is not safe. As the correction action for the problem situation solving is proposed the prolongation of the impeller's blades. The safety is detected for six variants of impeller with dierent blades length. For each variant, there is executed a modal analysis and its results are drawn up into the Campbell diagram. On the basis of this diagram, the safety of individual components is evaluated. The last part of the masters thesis concerns with the examination of the influence of blades length on the modal properties of the impeller.
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Design of a Very Low Specific Speed Pump
Chabannes, Lilian ; Sedlář, Milan (referee) ; Drábková, Sylva (referee) ; Rudolf, Pavel (advisor)
Čerpadla s nízkými specifickými otáčkami nacházejí uplatnění v široké škále aplikací, ale trpí nízkou účinností a rizikem nestability křivky dopravní výšky. Tato disertační práce pojednává o vylepšení hydraulických parametrů čerpadla se specifickými otáčkami ns = 32. Práce se zaměřuje na průtok v oběžném kole a ve spirále, které jsou řešeny pomocí CFD. Průzkum literatury ukázal, že přidání mezilopatek do průtokového kanálu je účinný způsob, jak zlepšit neuspokojivé proudění obecně přítomné v oběžných kolech s nízkými specifickými otáčkami. Byla zkoumána poloha mezilopatky v kanálu a vliv počtu přítomných mezilopatek. Část výsledků je ověřena experimentálně v laboratoři fakulty. Rovněž je zkoumán tvar spirály a pozornost je věnována numerickému řešení proudění u stěn a jeho vlivu na simulaci. Po numerických výpočtech na třech různých spirálách je navržen nový tvar, který zlepšuje vypočtové parametry čerpadla při nízkém i vysokém průtoku.
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The Delivery of the Mixture Containing Abrasive Particles.
Hrabina, Martin ; Sluše, Jan (referee) ; Štigler, Jaroslav (advisor)
The aim of this bachelor thesis is focused on description of the transport equipment parts used in some industries for delivering of the mixture containing abrasive particles. The thesis is divided into some captures. Each of them deals with the transport issues. The first part of the thesis is focused on the flow of liquid in transport equipment. Second part describes particular parts of pumps and compares various kinds of them, highlighting their advantages. One of the significant topics of the thesis is the characterisation of pipeline using for the above mentioned transport.
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Pump design
Mizera, Ladislav ; Svozil, Jan (referee) ; Klas, Roman (advisor)
This thesis considers the characteristic of hydrodynamic pumps. It describes the activity of these pumps and it shows the particular characteristic curves. Then the hydrodynamic pumps are divided and described. The biggest attention is attended to the vertical multistage centrifugal pump and shaft seal.
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Design study of sinus pump
Havlát, Pavel ; Kubálek, Jiří (referee) ; Pochylý, František (advisor)
This dissertation focuses on the construction design of a sine pump. It particularly deals with loss minimisation and strives to solve problems relating to excessive wear of the scrapergate which separates suction and the delivery space. The first part of the dissertation describes a new construction variation of a sine pump and the second part deals with a more detailed study including optimisation of one variation.
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The Different Kinds of the Sewage Delivery
Vosáhlo, David ; Haluza, Miloslav (referee) ; Štigler, Jaroslav (advisor)
The aim of this bachelor’s thesis is presenting the possibilities of different kinds of the sewage delivery. It is described a division and a brief overview of these types. Furthermore their main parts, function and using in practise are introduced. Pumps and their main components are depicted in the pictures or simple schemes.
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The Pump with a Diffuser with Stochastic Blades (Runner and Diffuser)
Dobšáková, Lenka ; Melichar, Jan (referee) ; Veselý, Jindřich (referee) ; Haluza, Miloslav (advisor)
This doctoral thesis studies the non-uniform blade cascade for centrifugal pumps. Influence of non-uniform blade cascade is investigated on the impeller and diffuser. A non-uniform blading impeller of pumps in this doctoral thesis was examined in terms of influence on efficiency characteristic. The idea of using non-uniform blading is to obtain a flat efficiency characteristic. Then the centrifugal pump could be used on larger scale of power with achieving a sufficiently high efficiency. The work is based on experimental measurements and numerical simulations of non-uniform hydraulic pump components. Non-uniform impeller and the diffuser were newly designed for this research. A new measuring track of small submersible pumps was needed to design and build for measurements. Different pump combinations with conventional hydraulics on one working point and hydraulics with non-uniform were measured. All measurements were evaluated and characteristics of efficiency, head and power were obtained for each measured combination. Some of pump combinations (which were measured in experiment) were numerically simulated by program Ansys Fluent. Data needed to evaluate the characteristic of efficiency and specific energy were collected from each numerical simulation. A theoretical consideration concerns the influence of non-uniform blade cascade applied on diffuser. The suggestion how to decrease hydraulic losses in canals was done. The theoretical consideration how to make a flat efficiency characteristic was made.
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