National Repository of Grey Literature 32 records found  1 - 10nextend  jump to record: Search took 0.02 seconds. 
Materials for space technology
Bačová, Alena ; Tříska, Václav (referee) ; Petrásek, Miloslav (advisor)
This master´s thesis is dealing with an analysis of materials used for space technology. The thesis is divided into eight main parts. The first part defines space technology. The second part introduces the issue of designing satellites and planning the space mission. The third part describes the effects of the environment on space technology before launch, during launch and flight, in space, and during atmospheric entry. The fourth part introduces the most used standards in Europe for the space industry. The fifth part analyses materials and their application in the space industry. The sixth part provides an overview of aerospace materials tests. The seventh part analyse processes and damage of material during and after the impact of a small object. The last part is devoted to the preliminary design of the device for a more accurate analysis of the behaviour of the material during the impact of a small object.
Overview of the development of small and medium lauchers
Dítě, Radovan ; Petrásek, Miloslav (referee) ; Daněk, Vladimír (advisor)
This bachelor's thesis describes the development of small and medium vehicle launchers. The dissertation is divided into four main parts. The first part deals with basic principles of rocketry and types of rocket propulsion. The second chapter describes historical develop-ment of rocketry. The third part describes the development of small and medium vehicle launchers. And the last part is dedicated to the description of current states of small vehicle launchers.
Design of the six seat helicopter with one turboshaft engine
Nasibullin, Bulat ; Tříska, Václav (referee) ; Petrásek, Miloslav (advisor)
The aim of this work is to develop a preliminary design of a six-seat helicopter with a turboshaft engine. The preliminary design of the helicopter consists of processing statistical data on similar helicopters, which are then, based on the specified requirements, used to estimate the basic weight parameters of the helicopter, the main geometric parameters and to determine the type and power of the propulsion unit. It consists of calculations of basic geometric parameters of the aircraft and engine selection. Part of another solution is the aerodynamic calculation of the supporting rotor, from which both the performance of the helicopter in suspension and in forward flight flow. In a special part of the project, the attention is paid to the system of balancing the reaction torque, in this case fenestrone and the solution is supplemented by some specific means installed on the tail beam, which help to balance the reaction torque and improve the directional control parameters of the helicopter.
An overview of atmospheric carriers for launching satellites into Earth's orbit
Bačová, Alena ; Petrásek, Miloslav (referee) ; Daněk, Vladimír (advisor)
This bachelor´s thesis is dealing with an overview of aircrafts designed as a launch platform for an air launch of satellite into the low Earth orbit. The thesis is divided into four main parts. The first part describes main principles of reaction engine and its two types of engines. The second part provides an overview of aircrafts as launch platform in the USA. The third part deals with these launch platforms in the former SSSR. The fourth part is devoted to aircrafts as launch platform in the Europe.
Preliminary Design of a Small Two Seat Helicopter
Junas, Milan ; Rozehnal,, Dalibor (referee) ; Petrásek, Miloslav (advisor)
The thesis deals the preliminary draft of the small two-seat helicopter with a piston engine. The aim of the thesis is not to propose a helicopter across the extent of the problems. Therefore we have chosen only selected issues which can be managed in the range of work. The introduction is focused on defining the general requirements imposed on proposed helicopter, formulating the basic conceptual and structural design according to the building regulation the relevant category. These ranges create a based assumption for right evaluation of the statistical analysis of the helicopters of the same or very near parameters category. Subsequently, there were defined the basic parameters of the proposed helicopter which make possible to solve the performance characteristics in the vertical and backward flight. The work is also focused on design of the rotor head of main rotor for the proposed helicopter, the definition of load acting on the rotor head, waving analysis and calculation of centrifugal forces acting on the main rotor blades. The design of the rotor head and also the helicopter as a whole will be graphically processed in the program Dassault Systemes Catia.
Age forming of aluminium alloys
Stanislav, Filip ; Petrásek, Miloslav (referee) ; Klement, Josef (advisor)
The diploma thesis is focused on the description and the verification of a relatively young creep age forming method. This method is based on a relaxation of stress and a creep of material, which occur by forming a part in the clamping tool during the artificial precipitation heat treatment at elevated temperature. After removing from the tool, the spring back and the residual stresses in the part are smaller compared to the conventional forming methods. This is mainly reflected in the increased fatigue resistance of the structure. The creep aging is only applicable to the precipitation heat treatable alloys. This thesis is focused on aluminium alloys, which are typical for the aerospace industry. The first part of the thesis describes principles of technology, its use in the aviation and material processes in the aluminium precipitation heat treatable alloys during the creep age forming. In the second part, there is a methodology of the verification of technology on samples made of the aluminium alloys ČSN EN AL-P 7075 and ČSN 424203 (approximate equivalent of ČSN EN AL-P 2024). Furthermore, a forming tool is designed, and experiments are performed according to the proposed methodology. At the end of the thesis, the experiments are evaluated and changes in the spring back of the samples are compared for three different methods of forming: the conventional cold clamping forming, the creep age forming and the creep age forming with an overaging.
Space Debris
Kvačová, Kristýna Kateřina ; Konečný, Pavel (referee) ; Petrásek, Miloslav (advisor)
The theoretical part of the diploma thesis focuses on the characterization of the artificial space debris in Earth's orbit. The methods of debris removal, the space debris mitigation guidelines, and related international documents are elaborated. In addition to, detection and monitoring of the orbital population are briefly described. The practical part of the thesis proposes a new method of debris removal which is aimed at CubeSat after mission ending in low earth orbit. The method consists of deorbiting maneuver, which is calculated, and the solid rocket motor for the maneuver performance. This includes the computation of dimensions of the solid rocket motor and the propellant configuration.
The Stress Analysis of the Beam with Thin Web - Influence of the Holes and Tensile Effect of Web Buckling
Horák, Marek ; Petrásek, Miloslav (referee) ; Jebáček, Ivo (referee) ; Píštěk, Antonín (advisor)
In design of an aircraft structure, the great emphasis is placed on achieving high weight efficiency. This thesis is focused on the stress analysis of the spars with thin web with or without web openings, which is one of the most important parts of the airplane structures. In comparison with traditional spars or beams, which are widely used in civil engineering applications, the design of the beam with thin web is more complicated. Thesis contains useful information for analytical calculation of this type of spars and its verification using finite element method and experimental measurement.
Modern Maintenance Procedures for Airframe Inspections for General Aviation Category Aircraft
Koštial, Rostislav ; Petrásek, Miloslav (referee) ; Třetina, Karel (referee) ; Hlinka, Jiří (advisor)
Aircraft scheduled maintenance requirements are rapidly extending and developing due to rapid evolution of small aircraft. This evolution leads to implementation of until recently exclusively airliner class maintenance standards. In the field of general aviation and FAR 23/ EASA CS-23 especially, preventive maintenance based on part replacing or repairing is still dominant. DAMAGE TOLERANCE philosophy implementation into an aircraft design influences maintenance procedures, which are adjusted to older SAFE LIFE philosophy. Aircraft manufactures are developing new ways, how to integrate requirements of damage tolerance application into scheduled maintenance procedures. Huge airliner manufactures (FAR 25/ CS-25) are using the ATA MSG-3 intelligent maintenance approach based on inspection. This dissertation thesis develops intelligent scheduled maintenance methodology, utilizing ATA MSG-3 procedures, expert knowledge and Multiple Criteria Decision Analysis (MCDA).
Dynamic Properties of Combined Rivet and Adhesive Bonded Joints
Urík, Tomáš ; Samek, Radko (referee) ; Petrásek, Miloslav (referee) ; Klement, Josef (advisor)
The improvement of static properties of combined rivet and adhesive bonded joints have been proven by several authors [1, 2]. On the other side, dynamic properties of joints (for example fatigue and corrosion) significantly affect final function of structures during their service life. In this thesis, the combine joints created by blind rivets and hyper elastic sealant are solved. Complex description of dynamic properties of this particular combined joining technology has not been publicised, yet. Description of sealant layer influence on stress concentration in rivet hole regions is one of the main goal of this work. The next stage of the thesis is focused on the influence of above mentioned sealant layer on fatigue properties of combined blind rivet and solid countersunk rivet joints. Stress strain analysis of rivet and combined joints done by FE analysis and by experimental optical measurement of strain field proved that hyper elastic sealant layer has a positive effect on decreasing of stress peaks in rivet hole regions. This findings are in direct compliance with fatigue measurement of combined joint (AAPL). The influence of applied sealant in this combined joints improved fatigue properties by twenty percentage increasing of stress to failure in comparison with rivet joints.

National Repository of Grey Literature : 32 records found   1 - 10nextend  jump to record:
See also: similar author names
3 PETRÁSEK, Martin
1 Petrásek, Marcel
3 Petrásek, Martin
3 Petrásek, Matěj
3 Petrášek, Michal
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