|
|
Heating of Family House by Heat Pumps
Sláma, David ; Moskalík, Jiří (referee) ; Lisý, Martin (advisor)
This bachelor thesis deals with heating of family house by heating pumps. The main task was to design a suitable heating pump for a chosen family house. Here is given the method of calculation total heat loss of building. Depending on the performance characteristics are compared two types of heat pumps, and will be selected the appropriate one. The last part compares the seasonal performance factors (spf) 3 and 5.
|
|
|
Pevnostní posouzení konstrukce výřezu dveří přetlakovatelného habitatu pro extrémní prostředí
Sláma, David ; Šálený, Vratislav (referee) ; Návrat, Tomáš (advisor)
Main goals of this master thesis are following: to perform the state of the art research of overpressure constructions (especially space habitats, plane fuselages); to create an own concept of the functional inside ending (hole) in the sandwich panel for a door; to perform stress-strain analysis of this concept; to perform the design optimalization of this concept in order to minimise the weight. To solve the problems above software Ansys 17.2 is chosen, because it allows to: model the material of the honeycomb core of sandwich panel as homogenous linear orthotropic material; evaluate reserve factors of all critical limit states; perform the design optimalization; perform Monte Carlo simulation. First and second design optimalizations discover, that with defined parameters: 0,635 mm width of aluminium sandwich face sheets and inner overpressure 0,1 MPa, a creation of the model, that would be safe by changing the values of design variables is not possible. Specifically, the maximum value of shear stress on the glued areas between aluminium face sheets and honeycomb core is higher than the shear strength of the glue. Therefore, two new concepts are created. First for inner pressure 0,03 MPa and bigger width of aluminium face sheets 3,175 mm, second for inner pressure 0,02 MPa and same width of aluminium face sheets 0,635 mm. For both these concepts, an overall reserve factor is calculated. First, the value of an overall reserve factor is calculated deterministically. Secondly, the value of an overall reserve factor is calculated stochastically considering the variance of material properties of the honeycomb core ± 10 % by Monte Carlo simulation. An overall reserve factor of the concept with inner pressure 0,02 MPa is determined as 1,21. An overall reserve factor of the concept with inner pressure 0,03 MPa is determined as 1,20. The weight of the concept for inner pressure 0,03 MPa is though 4 times bigger than the weight of the concept for inner pressure 0,02 MPa. In the concept for inner pressure 0,02 MPa the maximum value of HMH stress in aluminium components is critical, stochastically considered material properties of the honeycomb core don’t have a significant influence on this value. In the concept for inner pressure 0,03 MPa the value of maximum shear stress on the glued areas between aluminium face sheets and the honeycomb core is critical, stochastically considered material properties of the honeycomb core have a significant influence on this value. In the concept for inner pressure 0,03 MPa an absolute error of overall reserve factor is 8 % (overall reserve factor calculated deterministically was 1,28) which is significant. Monte Carlo simulation is also used to find that the value of Poisson ratio XY of the honeycomb core doesn’t have statistically significant influence on all limit states. Value of the reserve factor of the honeycomb core is higher than 2 in both concepts. Monte Carlo simulation discovers that this value can be significantly lower. Using Tsai-Wu failure criteria the reserve factor in the concept for inner pressure 0,02 MPa is determined as 2,72 deterministically x 2,41 stochastically (absolute error 31 %), in the concept for inner pressure 0,03 MPa the reserve factor is determined as 6,85 deterministically x 6,17 stochastically (absolute error 68 %).
|
|
|
A new design and technology of the low-pressure output part
Sláma, David ; Slaný, Martin (referee) ; Píška, Miroslav (advisor)
The aim of this work is make a new design and technology of the low-pressure output part of rail which is made in BOSCH DIESEL s.r.o. company. In the thesis is analyzed in detail the bending test, which is part of the quality control of the low-pressure welding joint. In the next part of the thesis is proposed the process of machining of this component, followed by experimental finding of welding parameters for resistance welding. Then several pieces are welded, which are measured and tested. The results of this tests are compared with customer requirements. Finally, a technical and economic evaluation of the change is made, which will save a considerable amount of money for the company.
|
|
|
Optimization of the safety shoe
Scholz, David ; Hrůza, Václav (referee) ; Sláma, David (advisor)
This thesis deals with designing shape modifications of a toecap used in Honeywell brand safety shoes. The thesis shows algorithm of compression test and impact test FEA in ANSYS software. The toecap was divided into areas according to von-Misses stress. Several modifications were made in all areas separately, according to design of experiments. Best of the modifications were combined together and two best combinations selected. The goals were verified by experimental testing of manufactured toecaps. The results were even a little bit better than simulations.
|
|
|
Stress-strain analysis of tooth with root inlay
Sláma, David ; Florian, Zdeněk (referee) ; Marcián, Petr (advisor)
This thesis deals with the dental biomechanics, specifically with root inlays. Most often, two specific types of these inlays are applied: steel and composite. These inlays are fixed to endodontically treated tooth canal with luting cement and finally the crown is fixed to these inlays. The advantage of this restoration is the fact that the prime periodontal connection between tooth and bone remains preserved. The main purpose of this thesis was performing research study of root inlays. In the next part of this thesis the Stressdeformation analysis was performed using computational modeling and better inlay (comparing two samples: steel and composite) was chosen according to a stress in the dentin. The solution of this problem was performed with Fined Element Method.
|
|
|
Příčiny nehod operátorů při práci s lesnickými harvestory a forwardery
Sláma, David
The aim of this bachelor thesis was to elaborate general information on the given topic, to evaluate and process the data obtained from individual operators and to subsequently perform statistics and graphical analysis of actual and potential causes of accidents of harvester and forwarder operators. The data were collected through semistructured interviews and questionnaires. In the semi-structured interviews, the real causes of accidents were investigated while potential causes of accidents were investigated in the questionnaires. The questionnaire method examined climatic, natural and soil conditions as well as human factors. The subject of investigation was the analysis and evaluation of the potential as well as actual causes of accidents.
|
|
|
Optimization of the safety shoe
Scholz, David ; Hrůza, Václav (referee) ; Sláma, David (advisor)
This thesis deals with designing shape modifications of a toecap used in Honeywell brand safety shoes. The thesis shows algorithm of compression test and impact test FEA in ANSYS software. The toecap was divided into areas according to von-Misses stress. Several modifications were made in all areas separately, according to design of experiments. Best of the modifications were combined together and two best combinations selected. The goals were verified by experimental testing of manufactured toecaps. The results were even a little bit better than simulations.
|
|
|
Finances of Territorial Units in the Czech Republic
Sláma, David ; Ochrana, František (advisor) ; Klimešová, Magdalena (referee)
Diploma thesis Finance of territorial units in the Czech Republic applies to analyze the self- governing budgets, especially municipalities. The thesis has the theoretical part and the practical one. An approach and function of public budgets and finance are described in the theoretical part. Following part of the thesis is devoting to the Czech budgetary system with the focus to municipal and region budgets. There are analyzed categories of income and expenditures. Budgetary expenditures are compared between municipalities and regions according to allocated field of application, according to the amount of capital expenditures. Another chapter is engaged in current issues in the municipality funding - there were changes in the system of tax distribution from the central government. The second issue is the growing indebtedness of Czech municipalities. The thesis tries to find some recommendations and solutions. The last chapter applies the financial and property analysis for the city of České Budějovice. An economy of the city is assessed according to chosen indicators, ratios and comparisons with budgets and assets between the years 2006 and 2011.
|
|
|
A new design and technology of the low-pressure output part
Sláma, David ; Slaný, Martin (referee) ; Píška, Miroslav (advisor)
The aim of this work is make a new design and technology of the low-pressure output part of rail which is made in BOSCH DIESEL s.r.o. company. In the thesis is analyzed in detail the bending test, which is part of the quality control of the low-pressure welding joint. In the next part of the thesis is proposed the process of machining of this component, followed by experimental finding of welding parameters for resistance welding. Then several pieces are welded, which are measured and tested. The results of this tests are compared with customer requirements. Finally, a technical and economic evaluation of the change is made, which will save a considerable amount of money for the company.
|
|
|
Pevnostní posouzení konstrukce výřezu dveří přetlakovatelného habitatu pro extrémní prostředí
Sláma, David ; Šálený, Vratislav (referee) ; Návrat, Tomáš (advisor)
Main goals of this master thesis are following: to perform the state of the art research of overpressure constructions (especially space habitats, plane fuselages); to create an own concept of the functional inside ending (hole) in the sandwich panel for a door; to perform stress-strain analysis of this concept; to perform the design optimalization of this concept in order to minimise the weight. To solve the problems above software Ansys 17.2 is chosen, because it allows to: model the material of the honeycomb core of sandwich panel as homogenous linear orthotropic material; evaluate reserve factors of all critical limit states; perform the design optimalization; perform Monte Carlo simulation. First and second design optimalizations discover, that with defined parameters: 0,635 mm width of aluminium sandwich face sheets and inner overpressure 0,1 MPa, a creation of the model, that would be safe by changing the values of design variables is not possible. Specifically, the maximum value of shear stress on the glued areas between aluminium face sheets and honeycomb core is higher than the shear strength of the glue. Therefore, two new concepts are created. First for inner pressure 0,03 MPa and bigger width of aluminium face sheets 3,175 mm, second for inner pressure 0,02 MPa and same width of aluminium face sheets 0,635 mm. For both these concepts, an overall reserve factor is calculated. First, the value of an overall reserve factor is calculated deterministically. Secondly, the value of an overall reserve factor is calculated stochastically considering the variance of material properties of the honeycomb core ± 10 % by Monte Carlo simulation. An overall reserve factor of the concept with inner pressure 0,02 MPa is determined as 1,21. An overall reserve factor of the concept with inner pressure 0,03 MPa is determined as 1,20. The weight of the concept for inner pressure 0,03 MPa is though 4 times bigger than the weight of the concept for inner pressure 0,02 MPa. In the concept for inner pressure 0,02 MPa the maximum value of HMH stress in aluminium components is critical, stochastically considered material properties of the honeycomb core don’t have a significant influence on this value. In the concept for inner pressure 0,03 MPa the value of maximum shear stress on the glued areas between aluminium face sheets and the honeycomb core is critical, stochastically considered material properties of the honeycomb core have a significant influence on this value. In the concept for inner pressure 0,03 MPa an absolute error of overall reserve factor is 8 % (overall reserve factor calculated deterministically was 1,28) which is significant. Monte Carlo simulation is also used to find that the value of Poisson ratio XY of the honeycomb core doesn’t have statistically significant influence on all limit states. Value of the reserve factor of the honeycomb core is higher than 2 in both concepts. Monte Carlo simulation discovers that this value can be significantly lower. Using Tsai-Wu failure criteria the reserve factor in the concept for inner pressure 0,02 MPa is determined as 2,72 deterministically x 2,41 stochastically (absolute error 31 %), in the concept for inner pressure 0,03 MPa the reserve factor is determined as 6,85 deterministically x 6,17 stochastically (absolute error 68 %).
|
guest ::
RSS feed.