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Vortex pump as a possible heart replacement
Coufalík, Martin ; Klas, Roman (referee) ; Klas, Roman (referee) ; Fialová, Simona (advisor)
The diploma thesis deals with the issue of artificial hearts and ventricular assist devices. The theoretical part describes the heart and its function. Blood is characterized in terms of rheological behavior and the possible criteria for hemolysis are discussed. The following section describes the most commonly used ventricular assist devices, with emphasis on the use of the regenerative pump, including its components. In the practical part, an experimental analysis of two pumps (COV 43 and COV 23) is performed. Furthermore, non-dimensional characteristics of the pumps are constructed using the laws of similarity. In the computational part, the CFD analysis of the regenerative pump is performed by means of stationary and transient calculation. The results are compared with the experimental findings and based on the results, the impeller of regenerative pump was modified.
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Extension of Centrifugal Compressor Operational Stability
Růžička, Miroslav ; Třetina, Karel (referee) ; Kmoch, Petr (referee) ; Klement, Josef (advisor)
Centrifugal compressors with high pressure ratio are widely used in small aircraft turbine engines and turbocharges. At high rotational speeds they have narrow stable operating region and commonly used impellers with back swept blades are not able to ensure requested stability. In order to achieve wider stable operating region, some other anti-surge measures can be used, such as an Internal Recirculation Channel (IRC) located in compressor impeller inlet. This thesis deals with an investigation of IRC influence on centrifugal compressor operational parameters. As a first, the various recirculation channel geometry was studied by using of CFD analysis on simplified computational models. Those geometry, which indicated best results in terms of mass flow and looses in channel were used for testing on a model test device. Subsequently the same geometry was tested on real centrifugal compressor in experimental turbine engine to verify influence of IRC on compressor performance map – pressure ratio and efficiency. Simultaneously the CFD analyses of IRC with a 3D model of compressor impeller were performed and results compared with those, gained from measurement on model and compressor. In addition the measurement of flow field downstream the recirculation channel outlet slot with using of 3-hole pressure probe was performed and compared with flow velocity profiles evaluated from numerical simulations.
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CFD analysis of icing effects on commuter aircraft configuration
Zima, Martin ; Navrátil, Jan (referee) ; Popela, Robert (advisor)
The Diploma Thesis concerns investigation of icing effects at L 410 NG aircraft. The aircraft is certified under FAR/CS/AP-23 Commuter category. An analysis was performed for existing Pneumatic De-icing Boots System at the wing area according to three flight configurations and icing conditions referring to document Part 25 Appendix C and O. The analysis was done by CFD solver FENSAP-ICE for various runs with respect to the icing envelope. Cases were assigned as two 2D cross-sections situated at the aircraft’s wing aileron part. Cross-sectional Reynold’s number oscillate between 4.5–8.5×106. Automatic operation of Pneumatic De-icing Boots System was proposed. Attention was paid to the ice accretion aft to the Pneumatic De-icing Boots System. The Appendix (Příloha) P6 contains an English written Article concerning main Diploma Thesis sections.
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Optimization of the siphon swirl turbine draft tube
Mach, Jiří ; Haluza, Miloslav (referee) ; Rudolf, Pavel (advisor)
The goal of this diploma thesis is to design a new shape of the draft tube, which will be easier to manufacture while maintaining good strength and hydraulic properties. First part of this thesis is devoted to the formulation of the problem, description of the swirl turbine, principle of operation, the basic variants of arrangement, also the function of the draft tube, its efficiency and other formulas. In the second part of this thesis is a CFD and strength analysis of the original design, also a new design is proposed and the possibility of optimization using ANSYS Fluent Adjoint solver.
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Volumetric losses
Feldová, Petra ; Sluše, Jan (referee) ; Klas, Roman (advisor)
The main goal of this bachelor thesis is to evaluate the flow of sealing gaps and assess the impact of the expansion chambers of various shapes , placing them in order to reduce volumetric losses . The first section summarizes theoretical knowledge of pumps, which suffer the most from these losses. There are also described the analytic solutions of flow in the cracks and possible use of simulation programs, such as Fluent, for investigation of more difficult tasks. The computational part compares analytically determined values of the volume flow for smooth gap, with the values obtained from the program Fluent. Thanks to the values from this program is also possible to assess the effect of rotation on the flows. Analytical relationships do not include this impact . For easier comparison the flow in the expansion chambers are further drawn contours of the static pressure, velocity vectors and pathlines in their cross-section.
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Modeling of Exhaust Manifold for Turbocharged Engine
Fanta, Tomáš ; Beran, Martin (referee) ; Svída, David (advisor)
This work describes different structural designs of the exhaust manifold and creation of parametric models of exhaust downpipes of supercharged engine 1,4 TSI. Next, the study deals with exhaust manifold’s materials and with present basic principles of thermodynamic and hydrodynamic. Then two parametric models were modelled in Solidworks software. First model was made according to existing exhaust manifold of engine 1,4 TSI. It was symmetrical model (collector in the axis). For second parametric model the collector was moved in horizontal direction, so this model is asymmetrical. Both models were evaluated considering their complexity of structural design and their manufacturing claims. Finally the possibility of CFD analysis for evaluation of parametric models was studied.
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Hydraulic design of inducer fuel pump for rocket engine
Kadlec, Jan ; Rudolf, Pavel (referee) ; Štefan, David (advisor)
The aim of this masters thesis is hydraulic design of inducer for given pump geometry and operating parameters. The first part of this thesis deals with cavitation problematic in hydrodynamic pumps. Next section describes two-dimensional design of the inducer and according to that, the 3D CAD model of inducer is made. The later part deals with thorough CFD analysis and determination of the main hydraulic parameters of inducer itself and also with whole pump completed with this inducer. The last section is devoted to inducer design improvement.
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Vane pump
Mach, Jiří ; Jandourek, Pavel (referee) ; Klas, Roman (advisor)
This work gives basic information about vane pumps, especially with unbalanced construction and vanes led by rotor. The first chapter generally gives an attention to pumps. There are described basic information, classification, advantages and disadvantages of the types, characteristics and calculation relations. The following chapters describe the vane pumps in the way of classification, description of function and calculation relations. There is also made a practical calculation of vane pump according to the assignment accompanied by CFD analysis.
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The computation of draft tobe of the turbine for giving parameters
Žák, František ; Veselý, Jindřich (referee) ; Haluza, Miloslav (advisor)
This diploma thesis describes design of a new shape of the draft tube for small hydro Katovice with maintaining built dimension. First part of this thesis is devoted to the formulation of the problem, description of basic function of the draft tube, its efficiency and other formulas. In the second part of this thesis the analysis is made for original design supported by CFD calculation. Furthermore a new design of the draft tube is made with comparison of original draft tube.
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Modification of a blood pump as a heart replacement
Simandl, Mirek ; Fialová, Simona (referee) ; Pochylý, František (advisor)
The master’s thesis deals optimization of regenerative pump and axial pump with ring motors that are designed as a heart replacement. Analysis of the koncepts is performed which were made in previous master’s thesis. There is created a new design of construction and hydraulition with using flat motors based on the analysis. The compact assembly of two impeller was formulated that replaced left and right heart and it served as a function of heart replacement. A functional model of the pump is created, there is measured characteristics of impeller and results are compared with CFD analysis. The design requirements some parts of the axial pump are added and it’s deviced feasibility analysis.
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