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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Měření dynamických charakteristik zpětných armatur / Measurement of dynamic characteristic of check valves

Novák, Jan January 2017 (has links)
Master thesis presents overview of existing types of check valves, their features, uses and issue called "cracking". Experimental part of this thesis focuses on the lift and swing check valves. Results of the measurement are evaluated from non-stationary flow point of view by developing and analyzing static and dynamic characteristics. This thesis takes into account losses and dynamic effects as main viewpoints. Two methods for measuring non-stationary velocities are used. Direct method called Gibson and indirect method laser doppler anemometry. Goal of the master thesis is to increase understanding of the check valves and their applicability.
102

Komplexní pevnostní návrh kondenzátoru / Complex strength design of condenser

Denk, Jakub January 2017 (has links)
This diploma thesis focuses on strength design of steam condenser. The goal of the thesis is to make strength calculations for the specific operation conditions, introduce possible solutions, provide recommendations and refer to weak points of such calculation procedures. First, thermal-hydraulic design in HTRI software is performed. Strength calculations respect ČSN EN 13445 standard. Strength calculation with imported temperature field is performed in ANSYS Workbench software. In the next step, another strength calculation is realized in Sant´ Ambrogio software. Results are evaluated in conclusion chapter, including recommendations for the possible following work.
103

Návrh dvoutlakého vertikálního kotle na odpadní teplo za plynovou turbínou na zemní plyn / Design of heat recovery steam generator with two pressure levels

Ptáček, Ondřej January 2017 (has links)
This diploma thesis deals with proposal of a two-lane vertical boiler using the waste heat after gas turbine. In the first part the heat calculation has been done followed by the arrangement of particular heat exchange surfaces and the drawing of real saw diagram. There are also dimensions of drums, inlet and outlet pipes and transfer pipelines drafted. Furthermore, I have listed the materials that are used for casing the boiler and pipelines. Finally, the boiler loss is calculated and the boiler hydraulic calculation is performed. The supplement contains a boiler drawing.
104

Automatizace a optimalizace konstrukce a pracovního procesu horizontální štípačky na palivové dřevo / Automatization a optimalization of desing and proces of firewood horizontal log splitter

Čechman, Jan January 2019 (has links)
Diploma thesis is focused on design and optimalization of log splitter. Thesis consists of search of log splitter types and common used technologies, mechanical design, optimalization, design of propultion system, risk analysis and financial overview. Log splitter is designed to meet needs of automatization. Safety, industrial design and ergonomy has been considered in the design.
105

Stanovení kapacity rozstřikovacího uzávěru v podmínkách omezeného výtoku / Hollow cone valve capacity in the restricted outflow conditions

Nehudek, Adam January 2015 (has links)
The thesis aims to determine the influence partial or complete submerge of hollow cone valve by outflow on its capacity without space restrictions, by outflow into discharge chamber and by outflow into water tunnel of circular cross section. The valve capacity is for mutual comparability purposes usually characterized by discharge coefficient. Research works have been performed on a spatial hydraulic model of the valve with inlet diameter D = 67 mm and an apex angle of a cone 90°. Values of the discharge coefficient obtained from measurements were statistically analyzed. The dependence of discharge coefficient, expressed by energy head, on submerged level was approximated by an exponential function. Exponent value of this function express the dependance rate of valve capacity on downstream water level. This procedure didn’t demonstrate signifiant dependance downstream water level on hollow cone valve capacity, only on tests at outflow to water tunel showed a low increase in the discharge coefficient partly due to the influence of kinetic energy of the stream flowing out of the tunnel on the energy head and also due to underpressure. Independence of discharge coefficient value on valve head has been prooved for head greather than 232 mm. Also was defined 3 stages of interaction outflow jet from valve and downstream water, some of them may cause on real waterworks structures unfavorable situations (may affect excessive load on valve by pressure pulsations). The presented results allow better evaluation of bottom outlets capacity at higher water levels, when the valves are flooded. Significant effect of sufficient aeration (especially in long water tunnels) on valve capacity was also confirmed. Taking into account on the specifics of hollow jet valves and cone valves, it is possible to generalize some of this resultos on them as well.
106

Výroba součásti z plechu s využitím technologie hlubokého tažení / Production single parts from sheet metal with usage technology deep drawing

Jurča, Jan January 2009 (has links)
JURČA Jan: The manufacturing of sheet metal part by deep draw technology. Thesis of Master´s Studies, the 5th Year of Study, the School-year 2008/2009, The Institute of Manufacturing Technology, Department of Machining, FSI VUT Brno.The thesis deals with the project of manufacturing the part of the car body – the fifth door by deep draw technology. The material is zinc-coated sheet metal HX220YD EN 10292. Mechanical properties and suitability of the material are evaluated by mechanical tests. The structure of the material is evaluated by metalography scratch pattern. The analysis of draw process and manufacturability of the part is made by calculations and AutoForm software. The production line, necessary machinery and construction solution of draw tool for the manufacturing the part are determined. Last section deals with economical evaluation of the production.
107

Konstrukce mobilního horizontálního štípacího stroje na dřevo / Design of mobile horizontal wood-splitting machine

Dressler, Jan January 2010 (has links)
This thesis shows making of documentation for production powerfull wood-splitting machine for hardest forestal work. There are researched and soluted all phases of pre-production machine's lifecycle, also means analysis of conception, potentional risks and failures analysis and also definition of required properties. Based on those properties and results of analyses is possible to setting up condition which should be satisfied. At following part are descripted and shown features of machine-design . Main feature (component) of machine is its frame, also there are strenght analysis of frame. Machine movement features are mainly hydraulics pistons which are powered by asynchronous engine, whith alternative possibility movement by wheel tractor power-take off shaft or hydraulics output. There are performed all important properties. Working safety questions and high endurability of machine shold be also performed. At the end of work is realised conception and design study of forestal production system for wood processing with one universal source of energy – wheeled tractor.
108

Návrh a výpočet výměníku spaliny -vzduch / Project and calculation of heat exchanger

Kóša, Štefan January 2011 (has links)
This master’s thesis is concerned with design of a heat exchanger for a unit with gas turbine. The pressurized air from the compressor is heated with flue gases from gasification and subsequent combustion of wooden biomass. Then it is led to the expansion turbine. For thermal and hydraulic calculations a program named HTRI Xchanger Suite® has been used. The thesis includes a brief description of heat exchangers, description of the used program, calculation and selection of input data, solving and conclusions. It contains also a layout of the exchanger.
109

Trhání vodního sloupce pod OK vodní turbíny při nestacionárních stavech. / Water column separation under hydraulic turbine runner during unsteady operating regimes.

Vašek, Lubomír January 2012 (has links)
In this diploma thesis called Water column separation under the hydraulic turbine runner during unsteady operating regimes are solved the pressure pulsations of the reverse water hamer. In the thesis is deduced a mathematical relationship of elaboration the numerice model which is based on equations of continuity and equations of forces equilibrium. Numerical model is created in MS Excel uses for computation the numerical method Lax-Wendrof that allows consideration of variable sound speed as function of static pressure and allows variable lenght step in computation domain. Reverse water hammer is in the thesis solved with consideration of rotating flow behind shut-off valve, where we expect forming of vortex rope. This situation can be applied on the closing water turbine which has vertex rope under turbine runner. Specifically for this thesis was carried out the experiment of the reverse water hammer. Constants going into numerical solution are optimalized with using experiment and pressure pulsation are compared between numerical solution and experiment.
110

Řízení polohového servomechanismu s nespojitou přestavnou rychlostí. / Position control of servo with discontinuouns rechangeable speed

Jindra, Pavel January 2012 (has links)
Diploma thesis work includes simulation of compensation of control for discrete. The aim of the work is a solution positioning control of servomotor drive piston, which is controlled by pass of the pressure oil with the help of several electromagnetically controlled switchboards with the orifice in the output channels. The verification activities of the regulated system is done using simulation in Matlab/Simulink and Matlab/Simulink, Matlab/Hydrosim. The requirement on the created model is to verify the behavior of the system to be modified to be used for the further development of the issue

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