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Adhezion wear mechanisms of moving engine parts
Cahová, Kristýna ; Válka, Libor (referee) ; Jan, Vít (advisor)
The thesis describes adhesion wear on a contact area between Common rail and the component and deals with various effects on this kind of wear. The aim of the thesis is to gain information about adhesion wear phenomena and to understands its physical principals. Theoretical part deals with description of Common rail and then it is focused on research of adhesion wear. Experimental part firstly summarizes available data from tests that have been already done and then continues with analysis of microstructure of materials which are in contact during assembling process and the formation of adhesion wear is increased there.
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Bonding of thin metal sheets
Poul, David ; Kubíček, Jaroslav (referee) ; Dvořák, Milan (advisor)
Bachelor thesis is focused on theory and methods of adhesive bonding. Experimental part is focused on two topics: determining dependences of bonded joint shear tension on a cure time and determining dependences of bonded joint shear tension on a size of contact area. Loctite SI 5399 RD acetoxy silicone one component glue was used for these experiments. At determining dependences of bonded joint shear tension on a size of contact area tension is raising, but the grow wasn’t directly proportional on the grow of size of contact area. Determining dependences of bonded join shear tension on a cure time it was proved, that tension is raising first 24 hours very quickly. After this period is process slowing down and tension is increasing to its maximum. After 18 hours bond tension is solid enough to be handling, but 24 hours of curing time is more secured.
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Hertzian contact apparatus
Marek, Jakub ; Křupka, Ivan (referee) ; Hartl, Martin (advisor)
This bachelor thesis deals with project and implementation of construction of the Hertzian contact apparatus based on commercial devices. This device will serve as education facility of Contact mechanics. Theoretical minimum needed for analytic calculation of contact between a rigid sphere and flat surface is mentioned in this thesis. Technical documentation is included.
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Slide Bearings Test Bench
Palán, David ; Knotek, Jiří (referee) ; Maršálek, Ondřej (advisor)
This master’s thesis is focused on measurement of electrical contact resistance. The beginning of the thesis is devoted to the introduction of the electrical contact resistance and electrical parameters of journal bearings. Next part of the thesis deals with engineering design of test rig. In order to verify functional measurement principle, the test rig based on engineering design has been made. In the end of the thesis the measuring devices and the measuring process is described. The measurement results from the test rig are presented.
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Experimental study of the starved lubrication
Novotný, Antonín ; Čermák, Jan (referee) ; Košťál, David (advisor)
This master’s thesis deals with the experimental study of an elastohydrodynamic contact under conditions of insufficient lubricant supply. Starvation level of this type of the contact may be experimentally determined based on the input position of the meniscus, but this way can’t determine all its levels of starvation. Consequent development in the field of tribology achieved theoretical model that can determine at all levels of starvation depending on the thickness of the lubricant film entering the contact, but it is relatively difficult for experimental verification. The main goal of this work is an experimental study and describes the behavior of elastohydrodynamic contact at an exactly defined thickness of the lubricant film at the contact input. The benefit of this work is a validation of that mentioned theoretical model for base oils and greases made from them, and mutual comparison of their behavior.
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The objectivization of evaluation of the dynamics of self-defense instruments
Beránek, Václav ; Šťastný, Petr (advisor) ; Pavlů, Dagmar (referee) ; Reguli, Zdenko (referee)
Title: The objectivization of evaluation of the dynamics of self-defense instruments Introduction: Strikes by the upper limb are key tools for the self-defense system. So far, mechanical properties have not been evaluated for a wider group of strikes without protective equipment with applications in training, injury risk assessment, forensic biomechanics and medical law. Objectives: The aim of this work is to compile and objectify the evaluation of the dynamics of a wider group of strikes by the upper limb by specifying the size of the contact area and describing the damping properties of the foam of the detection apparatus. The aim is to evaluate the impact force, the probability of exceeding the bone tissue fracture threshold, the impulse, the size of the impact surfaces and the pressure for three impact techniques, both sexes and two experience levels. Methods: The work consists of three projects. Two quasi-experiments were completed by 169 probands, men and women, experience levels beginner, advanced (n = 169, height 177.8±9.0; weight 81.6±17.8; age 27.3±8.1) within one period. Probands were measured on two devices (Kistler, Podokam), where the time, impact force of the blow was recorded and three segments of the upper limb were photographed. Probands performed 3 striking techniques, a total of...
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Adhezion wear mechanisms of moving engine parts
Cahová, Kristýna ; Válka, Libor (referee) ; Jan, Vít (advisor)
The thesis describes adhesion wear on a contact area between Common rail and the component and deals with various effects on this kind of wear. The aim of the thesis is to gain information about adhesion wear phenomena and to understands its physical principals. Theoretical part deals with description of Common rail and then it is focused on research of adhesion wear. Experimental part firstly summarizes available data from tests that have been already done and then continues with analysis of microstructure of materials which are in contact during assembling process and the formation of adhesion wear is increased there.
|
|
|
Bonding of thin metal sheets
Poul, David ; Kubíček, Jaroslav (referee) ; Dvořák, Milan (advisor)
Bachelor thesis is focused on theory and methods of adhesive bonding. Experimental part is focused on two topics: determining dependences of bonded joint shear tension on a cure time and determining dependences of bonded joint shear tension on a size of contact area. Loctite SI 5399 RD acetoxy silicone one component glue was used for these experiments. At determining dependences of bonded joint shear tension on a size of contact area tension is raising, but the grow wasn’t directly proportional on the grow of size of contact area. Determining dependences of bonded join shear tension on a cure time it was proved, that tension is raising first 24 hours very quickly. After this period is process slowing down and tension is increasing to its maximum. After 18 hours bond tension is solid enough to be handling, but 24 hours of curing time is more secured.
|
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Experimental study of the starved lubrication
Novotný, Antonín ; Čermák, Jan (referee) ; Košťál, David (advisor)
This master’s thesis deals with the experimental study of an elastohydrodynamic contact under conditions of insufficient lubricant supply. Starvation level of this type of the contact may be experimentally determined based on the input position of the meniscus, but this way can’t determine all its levels of starvation. Consequent development in the field of tribology achieved theoretical model that can determine at all levels of starvation depending on the thickness of the lubricant film entering the contact, but it is relatively difficult for experimental verification. The main goal of this work is an experimental study and describes the behavior of elastohydrodynamic contact at an exactly defined thickness of the lubricant film at the contact input. The benefit of this work is a validation of that mentioned theoretical model for base oils and greases made from them, and mutual comparison of their behavior.
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|
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Slide Bearings Test Bench
Palán, David ; Knotek, Jiří (referee) ; Maršálek, Ondřej (advisor)
This master’s thesis is focused on measurement of electrical contact resistance. The beginning of the thesis is devoted to the introduction of the electrical contact resistance and electrical parameters of journal bearings. Next part of the thesis deals with engineering design of test rig. In order to verify functional measurement principle, the test rig based on engineering design has been made. In the end of the thesis the measuring devices and the measuring process is described. The measurement results from the test rig are presented.
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