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Proposal of Engine Intake System with Exhaust Gases Recirculation
Vojkůvka, František ; Štěpánek, Karel (referee) ; Dundálek, Radim (advisor)
The object of the diploma thesis is to optimize vacuum function of the ejector using computional fluid dynamics, or CFD. The ejector is inserted to the intake system of the six - cylinder diesel engine to increase the pressure gradient of the exhaust gas recirculation system. The analysis of the current design solution is performed and then the ejector with the new shape affording higher vacuum effect is proposed. The introductory part is devoted to the questions of diesel engines emissions and technology to reduce emissions in the exhaust system focused on the EGR.
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Modeling of flow in ejector
Bílek, Martin ; Habán, Vladimír (referee) ; Štigler, Jaroslav (advisor)
This diploma thesis deals with the flow modelling in the ejector using the FLUENT software. It develops a diploma thesis created in the past, where a mathematical flow model in the ejector was created and experimentally tested. The aim of this work is to analyze the ejector calculations and to model a flow in an ejector of the same shape as in the experiment and under the same conditions, too. Another objective was to assess the influence of the throat length and to examine if the pressure in the ejector mixing chamber remains constant. Finally, the disagreement between the experimental figures and the ones gained from the mathematical model of the ejector are discussed.
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Experimental verification of ejector and creation of mathematical model.
Strmiska, Michal ; Štigler, Jaroslav (referee) ; Habán, Vladimír (advisor)
This diploma thesis deals with the area of ejectors. In the intoduction, an ejector is classed as an hydraulic machine. There is also an introduction of the principle and application of this machine there. The next part describes two different ways of calculation and there is a suggestion how to get characteristics, that were achieved by calculation in MS Excel, projected. The purpose of this diploma thesis is to confront this mathematical model with the experiment done in school laboratory at Kaplan department of hydraulic machines. The description of this experiment and the evaluation procedure of measured values is described in the final part of this diploma thesis.
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Steam turbine with ejector
Slezáková, Iveta ; Ing.Drahomír Maša (referee) ; Fiedler, Jan (advisor)
The main Target of this diploma is to find some reconciliation with cooperation of turbine and ejector. This work is containing informations about this mechanisms and also its historical development. The merits of this diploma thesis is thermodynamics calculation and proposal of main parameters and proportions of the turbine and the ejector. After this it is follow by the calculation of whole system of the turbine and ejector in consequence with calculation of turbine with by-pass regulation and also comparison of power output with ejector and with by-pass technology.
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Ejectors, its design and utilization
Dohnal, Jiří ; Kárník, Jan (referee) ; Štigler, Jaroslav (advisor)
This bachelor’s thesis deals with the area of ejectors. These machines are included in a group of a jet pumps, introduced in the first part of thesis. In the next part is an introduction of ejectors, their principal, characteristic, its design and function and differences of using gas and liquid in different combinations of driving or drifting medium. The most extensive part is about utilization in industry, medical care and other parts of life. In concluding part are some equations and laws using in design of ejectors. The biggest problem is their efficiency.
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Ejectors and it's utilization in industry
Zejda, Vojtěch ; Hájek, Jiří (referee) ; Vondál, Jiří (advisor)
This work aims at introducing ejector pumps. It describes the working principle, advantages and disadvantages and restrictions of their usage in various applications. Main disadvantage of ejectors is the low efficiency which limits the usage only in specific applications where it is not considered to be a crucial factor. Therefore, examples of usage of various ejectors in industrial processes are listed further. Last but not least, in these examples are also demonstrated difficulties and reasons why it is favourable to use an ejector rather than other types of pumps. Further off, this work deals with design methods of ejectors and compares their suitability. It appears that not all the methods are suitable for ejector design, because it depends greatly on presumed shape of a certain ejector. In the end, there is compared energy intensity of an ejectors and common centrifugal pumps and confirms energy disadvantage of ejectors.
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Design of injection mould for plastic component of spinning machine
Černohous, Josef ; Prokeš, František (referee) ; Koutný, Daniel (advisor)
Bachelor’s labour is concerned about present knowledge with injection moulding in first chapter, focused on machines forms, kinds of moulding materials. It also deals with technology of holding form temperature. In second chapter it engages with analysis and problem definition. Third part limits objectives of fourth part, form construction. There are single parts of moulding form closely described. Last chapter estimates construction based on it’s realization.
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BASIC CHARACTERISTICS OF ARRAY OF PULSATILE JET
Novotný, P. ; Vít, Tomáš ; Vestfálová, M.
The presented paper shows the results of measurement of basic characteristics of array of pulsatile jets which are used to enhance the efficiency of ejectors. Four pulsatile jets forms cross like structure where perpendicular couples are operating in two basic modes (a) in phase and (b) in antiphase. Paper presents phase averaged velocity profiles and velocity fields. All of the presented experiments are realized using hot wire anemometry method.
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