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Design of Elastomer/Glass Contact Experimental Apparatus
Štipák, Patrik ; Svoboda, Petr (referee) ; Hartl, Martin (advisor)
This bachelor thesis deals with project, manufacture and assembly of construction of experimental device – simulator of softEHD contact between elastomer and glass. This device will serve as research facility of lubricating layer thickness and frictional force at the contact. Similar solutions of other authors are mentioned in this thesis. Technical documentation is included.
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Shape Optimization of the Machine Components due to Variability of Input Data
Sawadkosin, Paranee ; Jonák, Martin (referee) ; Novotný, Pavel (advisor)
The objective of this Master’s thesis is to find shape optimal design based on min- imizing friction force of thrust bearing by using genetic algorithm(GA) which is one of an optimization toolbox in Matlab. Reducing the friction force of thrust bearing is one way of making shaft to decreasing friction losses. With four parameters of thrust bearing geometry number of segments(m), angle of running surface(), segment inner radius(R0), and segment outer radius(R1) substitute in Reynolds’ equation. In order to know friction force, it is necessary to generate a connecting variable, oil film thickness(h0) from loading capacity(W ) and revolution per minute(rpm). Friction power loss, as well as weight func- tion conclude the final shape optimization of thrust bearing: m = 7, = 0.1, R0 = 15 mm, and R1 = 20 mm.
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Pneumatic cylinder
Málek, Miroslav ; Štefan, David (referee) ; Klas, Roman (advisor)
Bachelor thesis contains description and categorization of pneumatic actuators, main part is devoted to linear pneumatic motors, their design and description of individual parts of the motor with respect to its function. Part of this thesis is devoted to buckling stability of the piston rod and brief description of the parts in the pneumatic circuit. Next part of the thesis is deals with description of mathematical model of pneumatic cylinder, which results in simulation of variables describing the operation of the motor. Simulation has been done on double-acting and single-acting pneumatic cylinder with return spring. This mathematical model also includes a friction force model.
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Shape Optimization of the Machine Components due to Variability of Input Data
Sawadkosin, Paranee ; Jonák, Martin (referee) ; Novotný, Pavel (advisor)
The objective of this Master’s thesis is to find shape optimal design based on min- imizing friction force of thrust bearing by using genetic algorithm(GA) which is one of an optimization toolbox in Matlab. Reducing the friction force of thrust bearing is one way of making shaft to decreasing friction losses. With four parameters of thrust bearing geometry number of segments(m), angle of running surface(), segment inner radius(R0), and segment outer radius(R1) substitute in Reynolds’ equation. In order to know friction force, it is necessary to generate a connecting variable, oil film thickness(h0) from loading capacity(W ) and revolution per minute(rpm). Friction power loss, as well as weight func- tion conclude the final shape optimization of thrust bearing: m = 7, = 0.1, R0 = 15 mm, and R1 = 20 mm.
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Pneumatic cylinder
Málek, Miroslav ; Štefan, David (referee) ; Klas, Roman (advisor)
Bachelor thesis contains description and categorization of pneumatic actuators, main part is devoted to linear pneumatic motors, their design and description of individual parts of the motor with respect to its function. Part of this thesis is devoted to buckling stability of the piston rod and brief description of the parts in the pneumatic circuit. Next part of the thesis is deals with description of mathematical model of pneumatic cylinder, which results in simulation of variables describing the operation of the motor. Simulation has been done on double-acting and single-acting pneumatic cylinder with return spring. This mathematical model also includes a friction force model.
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Design of Elastomer/Glass Contact Experimental Apparatus
Štipák, Patrik ; Svoboda, Petr (referee) ; Hartl, Martin (advisor)
This bachelor thesis deals with project, manufacture and assembly of construction of experimental device – simulator of softEHD contact between elastomer and glass. This device will serve as research facility of lubricating layer thickness and frictional force at the contact. Similar solutions of other authors are mentioned in this thesis. Technical documentation is included.
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The comparison of physics textbooks for basic schools
BUMBA, Tomáš
The goal of the theses is to determine, which physics textbooks are being used at primary schools, compare these textbooks and analyse the conception and the way various topics are elaborated. Another purpose of the theses is to didactically analyse the theme unit Force in textbooks from various authors and to create a new textbook based on the results and knowledge gained during the comparison. The effectiveness of the elaborated textbook was tested in practice. The textbook is designed as a new, practical conception for the tuition of the theme unit Force and should serve as a practical tool, which is even meant to be used for some of the experiments. It is focused on the most realistic aspect of the topic and works with the pupil´s desire to discover and learn new things. The effectiveness was tested didactically in a primary school class and compared with the results of another class, which used usual textbooks and was taught with usual teaching methods. The response of the pupils on the various methods was also of high importance. The results of the testing can be found at the end of the work.
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Properties of friction connections for blade dampers
Půst, Ladislav ; Pešek, Luděk ; Radolfová, Alena
Experimental laboratory equipment for direct measurement of friction forces was designed and realized. It is based on stiff prescribed relative motion. After connecting with measuring apparatus, a series of friction characteristic measurements with various combination of friction surfaces (blade material 7N, 671, wolfram carbide, chromium carbide) were carried out. Three levels of normal forces at several frequencies of relative motion were applied at each combination. The evaluation was focused particularly on ascertaining the dry friction coefficients. The analytic expressions for various relation strips “friction force - velocity” of relative motions were derived. These expressions can be applied at evaluation of experimental data or/and at numerical solution of machine dynamic problems. Nonlinear models of friction processes were linearized by the equivalent linearizing method.
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