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Noise reduction oriented optimization of UAV propellers
Ecler, Matěj ; Matějů, Jiří (referee) ; Popela, Robert (advisor)
This diploma thesis deals with optimization of propellers with the aim to reduce their noise level. Based on the measurement of noise level of serial propellers, major propeller noise sources were evaluated. Subsequent 2D simulations of the flow on the individual profiles along the propeller span revealed the locations of separation bubbles, which were identified as a potential source of the noise. Based on these findings, propellers were equipped with turbulator trips of various dimensions and their effect on the noise level and efficiency of the propellers was experimentally verified. The results did not show contribution of turbulator trips to noise reduction or efficiency.
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Competition Aircraft Model Tail Design
Hub, Pavel ; Šurkala, Martin (referee) ; Matějů, Jiří (advisor)
This bachelor’s thesis deals with an empennage design for a new competition aircraft. The introduction gives an overview of the Air Cargo Challenge 2019 competition and conceptual layout of the aircraft. The research part of the thesis is focused on possible tail configurations, tail parameters and a statistical analysis of commercially made aircrafts. The most suitable configurations are then compared in detail, during which basic longitudinal stability calculations are done. In the last part, load is calculated, followed by structural design and bearing components sizing.
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Optimized design of turbine engine intake
Kubo, Michal ; Matějů, Jiří (referee) ; Popela, Robert (advisor)
This master thesis deals with design of a subsonic intake which is used to supply small jet engine integrate into the fuselage of agile small unmanned aerial vehicle (UAV). Some kinds of these intakes are listed in order to inspire and introduce future designers into this part of jet plane design. This thesis contains a small amount of theory about compressible flow, and necessary knowledge which are important to know before the very first attempt to design an intake. Two models were designed in order to prove that the theory listed in this thesis is useful and can be used as a guide in design process of subsonic intakes. Both designs have the same layout. S-duct design with one intake placed on the belly of fuselage was chosen. After CFD analysis of first model it was found that there are huge area with separated flow and vortex. Separated flow leads to big total pressure loss and pressure distortion. While designing the second model the emphasis was to avoid this vortex and improve flow conditions. This optimization was success and the second design have smaller pressure loss in compare to the first design. The difference is more than 50% at fly speed M=0,8.
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Flight Simulator of General Aviation Aircraft
Mamula, Marko ; Koštial, Rostislav (referee) ; Matějů, Jiří (advisor)
This bachelor‘s thesis maps the major and mostly used commercial flight simulator softwares on the market, and points out the main differences in developing the aircraft in each simulator. It focuses on the flight simulator X-Plane and describes how it works with the flight model. The main goal of this thesis is developing a virtual model of an experimental aircraft VUT-061 Turbo and comparing its flight data with the data measured on the actual aircraft. Furthermore it suggests the adequate hardware needed for completing the physical simulator.
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Performance possibilities of VTOL Unmanned Aerial Vehicle
Bartlová, Tereza ; Matějů, Jiří (referee) ; Juračka, Jaroslav (advisor)
Tato bakalářská práce popisuje a vyhodnocuje výkonnosti bezpilotních leteckých prostředků se svislým vzletem a přistáním pro transport nákladu. První část práce popisuje problém v oblasti transportu nákladu a současně nastiňuje možné řešení tohoto problému pomocí bezpilotního leteckého prostředku. Dále je definována mise, kterou bezpilotní prostředek musí splnit, a podle této mise specifikuje výkonnostní požadavky na bezpilotní prostředek. V této části je rovněž krátce zmíněna problematika legislativy provozování dronů v Evropské Unii. Druhá část této práce se zabývá analýzami, pomocí kterých jsou posouzeny výkonnostní požadavky a odhad potřebného výkonu bezpilotního letadla pro splnění požadované mise. První analýza je založená na datech o letových výkonech existujících bezpilotních i pilotních letadlech. Druhá analýza se zabývá vztahem mezi výkonem a celkovou plochou vrtulí. Další analýza se zabývá vztahem mezi maximální vzletovou hmotností a celkovou plochou vrtulí. Na závěr je prověřen vliv různých konfigurací letadla se svislým vzletem a přistáním na potřebný výkon a celkovou plochu vrtulí. Třetí část této práce je zpracován prvotní konfigurační návrh bezpilotního prostředku se svislým vzletem a přistáním, s tandemovým uspořádáním otáčivých křídel osazených pohonnými jednotkami. Nejprve je pro tuto konfiguraci vybrán počet vrtulí a jejich průměr a také odhadnut potřebný výkon. Poté je popsán prvotní návrh hybridní pohonné soustavy. Následně je provedena hmotnostní analýza prvotního konfiguračního návrhu bezpilotního prostředku s hybridním pohonem. Na závěr po zhodnocení výsledků všech analýz, je prezentován výkres hrubého konfiguračního návrhu bezpilotního prostředku.
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Comparison of selected criteria of flight characteristcs on an airplane simulator
Melich, Peter ; Zikmund, Pavel (referee) ; Matějů, Jiří (advisor)
As of today, we might consider PC technologies as very progressive and advanced. Due to this fact, we have numerous commercial flight simulators available on the market nowadays. However, each flight simulator has it’s own specific characteristics and behaviour and that’s why I’m going to compare selected flight characteristics in the chosen flight simulator on a chosen aircraft type (Cessna 172SP in my case) and it’s comparison with measured data from real-life environment in this thesis. Data comparison will show us how accurately simulator responds to inputs from the user and if the simulation is similar in relation to real conditions.
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Alternative ways to take off and land for fixed-wing aircrafts
Cäsar, Tomáš ; Matějů, Jiří (referee) ; Zikmund, Pavel (advisor)
Target of this thesis was to propose and evaluate workability in matter of basic physical principles for shortening lengths of take-off and landing distances especially for small, single-seated aircrafts. These variants were proposed in order to be used at building roofs for transport of employees to work and back. Every variant is presented with loads, which would affect aircraft and pilot and also estimated runway length for comparison with classic landing. Calculations were made for two versions of aircrafts, one for present, achievable with current technologies and second futuristic, which takes into account expected development in aviation.
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Universal characteristics of piston engines with a propeller
Šafránek, Martin ; Matějů, Jiří (referee) ; Zikmund, Pavel (advisor)
Determining the characteristics of piston engines with a propeller is a complex task. Accurate calculations are based on engine and propeller characteristics from the manufacturers, which are, however, quite demanding. It is also possible to use simplified models that can predict the achievable values of propeller efficiency and fuel consumption. They are based on a simple propeller efficiency and maximum power. However, these models are often very inaccurate, which is a significant disadvantage. Therefore, it is possible to use the universal characteristics of propeller propulsion units, which offers a more accurate calculation of power and fuel consumption using a relatively simple model. The diploma thesis deals with a summary description of all characteristics of reciprocating internal combustion engines and propellers. A mathematical model was created here, which works according to a certain algorithm based on the joint work of the engine and the propeller. This model can predict the required power and fuel consumption in different flight modes much more accurately. The results were applied to the performance of ultralight aircraft, especially to the range, which was significantly increased.
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