Řada strojní. 2017, roč. 63 / Mechanical Series. 2017, vol. 63
Permanent URI for this collectionhttp://hdl.handle.net/10084/123526
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Item type: Item , Aspects of bubbling fluidized bed boiler control(Vysoká škola báňská - Technická univerzita Ostrava, 2017) Hrdlička, JanThis paper deals with fundamental aspects of controlling bubbling fluidized bed boilers (BFB) in comparison with air and oxyfuel combustion modes. The paper discusses fundamental requirements for operating parameters of such boilers that must be fulfilled in parallel, particularly fluidized bed temperature, fluidization mode and complete burnout of a fuel.Item type: Item , Measurements of Shock Compression(Vysoká škola báňská - Technická univerzita Ostrava, 2017) Šmída, Zdeněk; Kolarčík, KamilThis article was written based on the topic of student's dissertation. This is the research of shock phenomena which may occur, under certain conditions, by operation of displacement compressors with the Built-in pressure ratio. These phenomena are called the Shock compression and the Shock expansion or we can use terms “Under-compression” and “Over-compression”. The contribution describes current possibilities of a measurement Shock compression at the experimental measuring stand in Laboratory of displacement compressors which is owned by Department of Power Engineering, Faculty of Mechanical Engineering and VŠB – Technical University of Ostrava. The contribution deals with the analysis of the experiment and as well as the results obtained which confirm some the conclusions of the Basic physical model.Item type: Item , Cogeneration Cycle in Water Heating Boilers(Vysoká škola báňská - Technická univerzita Ostrava, 2017) Ostrowski, Piotr; Pronobis, MarekCogeneration – joint generation of electricity and heat brings savings in consumption of primary fuels. Therefore, it contributes to reduction of harmful substances emission to the atmosphere (CO2 emission), which also means reduction of external costs of energy and heat generation. Until present, the cogeneration cycles have not been used in heating plants equipped with water boilers (in particular the water-tube ones). This paper presents a concept of innovative cogeneration cycle which operates with a water heating or industrial boiler. The cogeneration cycle does not change the approval of technical parameters of the boiler and it does not limit the scope of its use. The developed comparative cycles in the h-s and T-s systems and simulation model of the unit cogeneration cycle are presented as diagrams and cogeneration indicators. Furthermore, economic indicators of cogeneration are presented for water boilers.Item type: Item , Incorrect Connection of the Pump in the Heating System(Vysoká škola báňská - Technická univerzita Ostrava, 2017) Novotný, Petr; Hujer, JanThe expert literature describes the adaptive mode of a pump as one possibility for the significant savings in electricity consumption for heating in residential buildings. However, there are examples where a project, based on the superficial knowledge of advertising leaflets leads to mistakes and does not save energy. The end user is mistaken that no better solution exists. One example of incorrect boiler project is rectified and calculation of electrical energy savings is made.Item type: Item , RDF (50% Sewage Sludge, 50% Plastics) Gasification Process Analysis(Vysoká škola báňská - Technická univerzita Ostrava, 2017) Maj, Izabella; Ostrowski, Piotr; Kalisz, Sylwester; Wolniak, MateuszThe paper presents analysis of alternative fuel gasification with use of flue gas as a gasifying agent. As a result of a process syngas with combustible components (CO, H2, CH4, CnHm) was obtained. Laboratory tests were carried out to determine usability of selected alternative fuel to low-temperature gasification process. Tests were conducted in a laboratory reactor allowing to gasify a fuel sample of appx. 1 g. The experimental stand enables recording of a sample weight loss and syngas composition. The process takes place for fuel samples of a constant weight and different granulation and with a set composition of flue gas used as a gasifying agent. The aim of the laboratory research was to determine the usability of RDF fuel for indirect co-firing in power boilers and to build a knowledge base for industrial-size process by defining the process parameters: kinetics (time for fuel to remain in the reactor), recommended fuel granulation and process temperature.Item type: Item , MPC Control for Superheated Steam Temperature(Vysoká škola báňská - Technická univerzita Ostrava, 2017) Hýl, Radim; Wagnerová, RenataThis contribution deals with design and implementation of control system for superheated steam temperature, which is most often carried out by injection of the feed water. In the proposed control system, a common cascade control system is replaced by a predictive controller. This can quickly respond to rapid and unpredictable changes in steam consumption. The accuracy of the predictive controller design has been verified not only by digital simulation but directly in real process. The quality of the newly designed controller was compared to the originally implemented cascade control.Item type: Item , Characterization of Biomass Fuels in Isothermal Plug Flow Reactor (IPFR)(Vysoká škola báňská - Technická univerzita Ostrava, 2017) Gądek, Waldemar; Ƚyczkowska, Angelika; Scherrmann, Alexander; Gehrmann, Hans-Joachim; Szlęk, Andrzej; Seifert, Helmut; Stapf, DieterCombustion of fossil fuels is one of the most important source of energy. However low carbon politics and environmental commitments, affects developing combustion and co – combustion technologies. Utilization of biomass fuels can be answer for new challenges, although more research on effective utilization of these fuels are needed. Nowadays, combustion of biomass fuels, especially straw, causes many technical problems, mainly slagging formation, fouling of heat exchangers inside combustion chamber and insufficient fuel burnout. This paper focuses on analysis of biomass combustion. Better knowledge of behavior during biomass combustion may help to optimization of PF (Pulverized Fuel) boiler of and avoid some technical problems. The results of investigation shows that temperature and oxygen concentration in reactor play significant role in process of devolatilization and char burnout. For instance during char burnout experiments at temperature 850⁰C at 14% oxygen concentration after 200 ms more than 80% of mass loss were achieved. Compared to 700⁰C at 14% oxygen concentration this same level of mass loss were completed after 500 ms. Experiments performed on Isothermal Plug Flow Reactor (IPFR) at Institute of Energy Process Engineering and Fuel Technology (IEVB) at TU Clausthal were a part of project between IEVB and the Karlsruhe Institute of Technology (KIT) in Germany.Item type: Item , Reconstruction of Research Gasification Technology at the Energy Research Center(Vysoká škola báňská - Technická univerzita Ostrava, 2017) Friedel, PavelGasification technology was one of the first large projects of the Energy Research Center at the VSB - Technical University of Ostrava. The beginnings of the technology date back to 2006, when construction of the first version of the gasification plant with an autothermal generator was started. During these years of operation, a lot of testing was conducted on the technology to test different types of fuel (pellets from rice husks, pellets from miscanthus, straw pellets, RDF and many other types of fuels) and various modifications to the technology (testing of two cyclones, dolomite reactor testing, scrubber testing). Subsequently reconstructed gasification technology held tests by RDF fuel, wood pellet and mixtures of these fuels. The tests of the fuel was conducted at three temperatures (750, 850, 950 ° C).Item type: Item , Mechanical Properties of Steel DC01 Formed by Drece Method(Vysoká škola báňská - Technická univerzita Ostrava, 2017) Švec, Jiří; Rusz, Stanislav; Hilšer, Ondřej; Ochodek, Vladislav; Krejčí, LucieThe main goal of the paper is a review of current achieved results given by processing of steel DC01 by DRECE (Dual Rolls Equal Channel Extrusion) forming process, whose prototype equipment has been put in service in the end of 2009 at VŠB – Technical University of Ostrava, Faculty of Mechanical Engineering and Department of Mechanical Technology. The paper analyses the effect of the DRECE forming process on the mechanical properties and deep – drawing sheet metal formability of the steel DC01.Item type: Item , Cooperation of Business And B2B Marketing Activities in an Industrial Company(Vysoká škola báňská - Technická univerzita Ostrava, 2017) Nečas, LiborThe organizational arrangement of departments in Czech industrial companies is very often subject to conservative tendencies, and new elements are accepted with skepticism. Industrial B2B marketing is a functional area that was not contained in company structures for decades of years. Although consumer marketing (B2C) has already been established in enterprises, its B2B antipode still tries to find its place and is apprehended insufficiently. It has been fighting a battle with sales departments, even though their functions should complement each other and activities should be mutually cooperated. This article tries to find a system in the content of marketing and sales activities and derives their optimal integration in the structure of an industrial company.Item type: Item , The Use of Association Rules in The Analysis of the Trends of Alarms(Vysoká škola báňská - Technická univerzita Ostrava, 2017) Landryová, Lenka; Urban, PatrikThis article deals with acquired alarm logs analyses, the alarm logs from control systems, and explains the reasons for its collecting and implication of the analyses. Several existing platform solutions can be used to analyze the alarms from the historical trends, and solutions, which offer the filtering of events based on time units to obtain the data about the maximum and average number of logs. This paper contributes to this area by developing a graphical interface for a system that makes it possible to use the analysis by association rules and brings the possibility of detecting frequent and repeating patterns in acquired alarm data files.Item type: Item , Input Shaping for Underdamped Systems(Vysoká škola báňská - Technická univerzita Ostrava, 2017) Jurek, MartinThe main aim of this paper is to provide possibility to test and validate multiple damping and input shaping methods for underdamped systems. Mathematical model for specific development and demonstration was created in Matlab Simscape environment. Additional Matlab Simulink system was modelled to achieve proper data acquisition and comparison in contrast to plain system without any special damping methods.Item type: Item , Grain Refinement of Extruded AZ31 Magnesium Alloy by Ecap Process(Vysoká škola báňská - Technická univerzita Ostrava, 2017) Hilšer, Ondřej; Rusz, Stanislav; Krejčí, Lucie; Špalek, FrantišekExtruded Mg – 3%Al – 1% Zn (AZ31) magnesium alloy was subjected to ECAP (Equal Channel Angular Pressing) processing at 523 K (250 °C). At the processing temperature of 523 K, fine grains with the average grain size of 2 – 3 μm are formed as a result of dynamic recrystallization originated by fine Mg17Al12 (γ) phase particles having 200 nm diameter dynamically – precipitated during ECAP processing. Microstructural evolution during ECAP was studied systematically using optical microscope and transmission electron microscope.Item type: Item , Variable Pitch Propulsion Drive Model(Vysoká škola báňská - Technická univerzita Ostrava, 2017) Gebauer, Jan; Wagnerová, RenataThe contribution deals with the mathematical model of the propeller drive unit with variable pitch. The introductory part of the article aims at a general mathematical description of the internal structure of the aircraft propulsion. The DC motor and propeller model are presented in next chapter. The last part presents the comparison between MatLab Simulink model and experimental laboratory stand of variable pitch drive unit. Variable pitch propeller drive is useful to minimize power consumption. The use of these units for the drones is only experimental in terms of optimization of energy consumption.Item type: Item , Determination of Measurement Uncertainty of Strain and Stress Using Strain Gages(Vysoká škola báňská - Technická univerzita Ostrava, 2017) Dokoupil, PavelThe article deals with the determination of measurement uncertainty of strain and stress using resistance strain gages. You can find two methods to define the uncertainty in the article, GUF and MMC, and both are applied for measurements carried out with resistance strain gages. Definition of the measurement uncertainty was set for the strain measured by uniaxial and biaxial strain gages. The uncertainty of the stress was defined for linear strain gages, T-rosettes and Rosettes. There were universal mathematic-technical models defined to measure strain and stress. These models can be used either for standard and special measurements i.e. high-temperature, or for measurements in radiation field. Each part of the strain and stress uncertainty is analysed from the point of view of a size and shape of probability function error that strain and stress can adopt. The maximum focus was dedicated to the errors influencing measured strain like strain gage properties, installation and operating influences, external influences, time effects and the influence of the measured object. There are two errors influencing the mechanical stress described and analysed in the thesis, the error of the Young’s modulus of elasticity and the error of the Poisson’s ratio.Item type: Item , Windows 10 IoT Application for Data Acquisition from Sensors(Vysoká škola báňská - Technická univerzita Ostrava, 2017) Babiuch, MarekThe paper describes the creation of Windows IoT applications in Windows 10, specifically on mobile device for collecting and displaying data obtained from sensors connected to the Arduino development board. This article describes all the steps necessary to create an application in C #, development tools, hardware devices, and libraries in a compact summary which forms the algorithm of the implementation of Windows Universal Application on so-called IoT devices from different manufacturers.