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Life cycle assessment methods for BEV and PHEV batteries
Dvořák, Matouš ; Pokorný, Jan (referee) ; Fišer, Jan (advisor)
Electromobility is a current topic and a way to reduce the carbon footprint not only in personal transport. The operation of an electric car does not have a direct impact on emissions compared to an internal combustion engine car. However, the issue remains the production of the battery, which contains rare metals that are very energy and environmentally demanding to extract. The aim of this thesis is to analyse the energy consumption and emission footprint of the production of different types of batteries. The thesis includes a general introduction to the Life Cycle Assessment (LCA) method, followed by a chapter on battery design and the classification of batteries according to electrode chemistry. The analysis of LCA studies of batteries shows that the least energy intensive battery in terms of production is the battery with NMC cathode and in terms of emissions it is the battery with LMO cathode. However, the results are strongly influenced by the input data, which are often different in LCA studies, so it is not possible to draw a clear conclusion. Part of the thesis deals with the analysis of the environmental impacts of battery production using different energy mixes and different types of production technologies. The work can serve as a basis for a more detailed investigation of the production part of the battery and for minimizing the environmental impact of this process.
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Visualisation of the flow in the ventilation unit
Šebetka, Kryštof ; Fišer, Jan (referee) ; Pech, Ondřej (advisor)
This bachelor thesis deals with the basics of hydrodynamics. The basic principles and functions of flow visualization are described. Different types of visualizations are also discussed, followed by a list of specific visualization methods that are described in more detail. Another topic is ventilation and air conditioning. The thesis includes a short summary of the historical development of ventilation and air-conditioning and brief information about this industry. General descriptions of the components that are most relevant to the industry are also covered. Then the thesis comes to the experimental part, where is description of the ventilation unit inside which the flow visualization was performed. This is followed by the description of the experiment itself, the aim of which was to perform the flow visualization by the smoke method inside the ventilation unit, the construction of which was gradually modified to make the visualization as simple as possible and as recognizable as possible. The apparatus for the visualization is described, as well as the process of gradual development of the unit, how the different components had to be modified to improve the quality of the visualization. This is illustrated in photographs showing the flow before and after the modifications. The last section describes the process of trying to reduce the pressure losses that occurred between the different components of the ventilation unit, which were measured and compared at different stages of the modifications.
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Optimization of the cockpit ventilation system of a small transport aircraft
Vícena, Ondřej ; Charvát, Pavel (referee) ; Fišer, Jan (advisor)
This thesis deals with the optimization of the cockpit ventilation system of a small transport aircraft. The current system does not allow the ECS system to function without activating the main engines, which limits its effectiveness in ground operations. The theoretical part provides a basic theoretical framework for understanding and evaluating the thermal comfort in the cockpit, including heat transfer modes, cabin microclimate during different operating modes, and the definition of fundamental concepts related to ECS in pressurized and non-pressurized cabins. The experimental part focuses on the extension of the system with a suitable electric motor fan to provide cabin air supply even during ground operations at the airport. It includes testing the thermal effect of the supplied untreated air on the human body using a thermal manikin and a cabin simulator. In addition, heat removal from the body surface and subjective thermal sensation at different airflows and outlet routing were investigated for ambient temperature.
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Sleep quality depending on room environment
Veličková, Kateřina ; Pokorný, Jan (referee) ; Fišer, Jan (advisor)
The aim of this diploma thesis was to determine the thermal resistance of selected sleep assemblies (clothing, mattress, blanket, pillow) using measurements with a thermal manikin and subsequently to determine the appropriate ambient temperatures at which a balanced thermal equilibrium between the sleeping person and their environment would be maintained. Four different assemblies were selected for measurement purposes, differing in the type of blanket used (summer blanket, quilt, cover, and no blanket). The influence of the thermal manikin's position on the measured value was also investigated. It was proven that the influence of position on the overall thermal resistance is negligible, with measured values ranging from 1.12 clo (assembly without a blanket in the side position) to 2.05 clo (assembly with a summer blanket in the back position). Subsequently, appropriate ambient temperatures were determined using the PMV model, which ranged from 24.4 °C to 28.6 °C. The two-node model proved to be insufficiently sensitive for the addressed issue, and the heat flux maps derived from the equivalent temperature model were not calibrated for sleep but for mild activity while seated. Nevertheless, they provided interesting information about the perception of thermal comfort in different parts of the body.
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Ventilation and air conditioning of a car cabine
Viščor, Petr ; Hejčík, Jiří (referee) ; Fišer, Jan (advisor)
In this work are described kinds and functions of air-conditioning systems which are used in cars. Further is described heat transfer between car cabin and ambient environment and issue of reduction of air-conditioning energy consumption. Last part of the work contains numerical simulation made by the THESEUS-FE 2.1 software package. This simulation was done on a model of the Toyota Prius car and was focused on effect of glazing on a temperature of the air inside the car cabin during hot summer days.
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Air-conditioning of office rooms
Taclík, Jakub ; Toma, Róbert (referee) ; Fišer, Jan (advisor)
The aim of this diploma thesis is to design the air conditioning system for one floor of the offices. The thesis is divided into theoretical, computational and design part. The computational part consists in determining the amount of ventilation air, calculation of heat losses, heat gains and psychrometric calculations for summer and winter season. Based on the calculated values, air ducts, end-points and air-conditioning units are designed. The diploma thesis is supplemented with a list of materials and drawing documentation.
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Database of typical clothing for cabin of cars
Toma, Róbert ; Pokorný, Jan (referee) ; Fišer, Jan (advisor)
In this bachelor thesis, there are processed databases of typical clothing for cabin of cars. Data are based on information from survey for both women and men for three seasons – summer, transitional season and winter. There are mentioned factors which affect thermal comfort and thermoregulation of human body. The thesis includes options how to measure thermal comfort and how we can evaluate results on different scales. Next, I process the way how we measure thermal resistance of each databases of clothing. Measurements are placed in climate chamber in VUT Brno and we are using manikin Newton made by Measurement technology Northwest. In the end, we mention some results and comparison of both genders.
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Hydrogen vs. electricity - comparison of energy performance of EV powertrains
Šándor, Kristián ; Mišík, Ondrej (referee) ; Fišer, Jan (advisor)
The topic of emission reduction and the increase in the share of energy produced from renewable sources remains actual and highly discussed in 2021. It was the major reason why I chose to compose this bachelor’s thesis, in which I aim to critically evaluate and compare the energy performance of an electrical vehicle and a hydrogen vehicle. The theoretical part of the thesis outlines the aforementioned drivetrains as well as the plug-in hybrid drivetrain. The practical part of the thesis focuses on calculations of the energy performance of the drivetrains for the year 2021 with a rational estimate for 2050. The methods of electricity and hydrogen production are crucial for energy performance evaluation. Data shows that electric cars operated in countries with a high share of energy produced from renewable sources are the least energetically demanding. On the other hand, if the energy production depends predominantly on fossil fuels, it is more efficient to operate a hydrogen vehicle. Calculations show that when considering the indirect emissions during the operation as well as the energy performance, the plug-in hybrid vehicles are the least efficient. The difference in efficiency between electric and hydrogen vehicles varies depending on the mode of energy production of that specific country. The conclusion of this thesis also discusses advantages, disadvantages and technological challenges concerning the aforementioned drivetrains.
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Air conditioning systems of residential buildings and one-family houses
Verfl, Jan ; Fišer, Jan (referee) ; Janotková, Eva (advisor)
Airconditioning now a days became important equitment in every household. It keeps optimal microclimate and thermal comfort. The first chapter describes valuatiuon of microclimate and termal condition of enviroment and also termal transport in between human body and enviroment. The second chapter desribes conditioner and its main parts, division of aircondition systems and their estimation.
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