|
Calculation of thermal resistance of finned heatsink
Kyanka, Radim ; Huták, Petr (referee) ; Toman, Marek (advisor)
This bachelor's thesis is focused on the problem with analytical calculations needed to define thermal resistance of finned heat sinks. First it describes how temperature proceeds at different boundary conditions at fin tip. Than it describes different mechanisms of heat transfer, equlation of heat resistance especially of natural and forced convection. To verify the results there is comparison between analytical equlations written in Matlab program and measuring results.
|
|
Trasfer Heat Analysis in Steam Generators in blocks of VVER 440
Roupec, Petr ; Pulec, Jiří (referee) ; Šen, Hugo (advisor)
The aim of this thesis is to analyze the heat transfer in steam generator of blocks in the nuclear power plant VVER 440. The steam generator represents the border between the primary and the secondary circuit. The heat is carried from a warm water from reactor to a cold water. The steam arises after the heat transfer and drives the steam turbine. An important quantity which represents the heat transfer is a heat transfer factor. This thesis is divided into theoretical and a practical part. In the theoretical part is mentioned a principle of the steam generator and the theoretical calculation of the heat transfer factor, which comes first of all from the character of the streaming in the steam generator. The practical part brings a comparison of the heat transfer factor calculated from data measured after the start of the third block of EDU in 1986, with the heat transfer factor which comes from the measurement after the power-increase for 105 % of nominal power of the same block in 2009. Further is shown the prediction of the heat transfer factor for next power-increase and the following service is shown too.
|
|
Topical and Advanced Possibilities of Heating by Thermal Pumps
Božek, Michal ; Brázdil, Marian (referee) ; Lisý, Martin (advisor)
The bachelor's thesis is focused on search of one of the many methods of home heating systems, specifically on heat pumps. The first part describes the structure of heat pumps, the principle of how they work, main types, their two most important parameters and comparison of them to other systems of heating. The second part contains comparison of individual heating systems from economical point of views on a selected model house.
|
|
Design of Interior Heating Element
Juráňová, Zuzana ; Křenek, Ladislav (referee) ; Rubínová, Dana (advisor)
The topic of my bachelor´s thesis is design of interior heater. The aim is to design the kind of heater which will follow technical, ergonomic and esthetic requirements. There should be a possibility of using it in any room and it will be able to compete with the radiators on today´s market.
|
|
Optimization of Cooling Synchronous Machine
Makki, Zbyněk ; Rafajdus,, Pavol (referee) ; Kačor,, Pavol (referee) ; Janda, Marcel (advisor)
The main goal of doctoral thesis is optimization cooling of the synchronous machine. Problem is solved based on the finite element method with use of ANSYS software. Work is built up from theoretical part where is comparison of base equations for heat transfer and simulations for several models. Next part shows us two methods how simulate free and force convection. Depends on the better method from the previous two methods is used for next calculations with several algorithm which are used for find of best parameters for synchronous machine. Our control parameter is mass flow rate.
|
|
Temperature changes during pulse charging of lead-acid accumulator
Přikryl, Kamil ; Bača, Petr (referee) ; Křivík, Petr (advisor)
This master's thesis deals with the issue of lead-acid batteries, their charging methods and issue of thermal processes in lead-acid batteries. The thesis is divided into three main parts. The first section describes the theoretical knowledge of lead-acid batteries, such as history of lead-acid battery, structure, principle of operation, methods of charging and thermal processes taking place in the lead-acid battery. The second part describes in detail the production of experimental electrodes. The last section describes the automatic data logger for measuring and experiments, which were focused on pulse charging method with variable duty cycle pulses.
|
|
Current distribution and heat losses in the low voltage circuit breakers
Musil, Pavel ; Janda, Marcel (referee) ; Makki, Zbyněk (advisor)
The work is focused on the calculation of decomposing the current and the thermal loss in circuit breakers of low voltage. In the work´s first half, there is a summary of the most frequently used circuit breaker elements with a focus on their constructional layout. The biggest attention is devoted to the circuit breaker marked LPN-16B by the company OEZ. A model of the under current trajectory of this specific element is created in a program Inventor on which the following calculation of decomposing the current and thermal loss was accomplished in a program Ansys. The obtained results are assessed in the conclusion of this work.
|
|
Analysis of Heating Systems for Family House
Holubka, Oleksandr ; Elbl, Patrik (referee) ; Lisý, Martin (advisor)
The aim of this bachelor’s thesis is the assessment of options and innovations when it comes to heating of family houses. These options are then compared. In the last part of this thesis, the gathered insight is used for a technical and economical evaluation and subsequent proposal of a heating system of the model house.
|
| |
|
Heat pumps for heating and hot service water preparation
Valášek, Martin ; Hrnčířová, Michaela (referee) ; Kracík, Petr (advisor)
This bachelor’s thesis is aimed to describe heating and water warming in the detached houses by basic technical devices and there are suggested various types of heat pumps for a particular object. These heat pumps are compared technically and economically. In the beginning of the thesis there is a summary of the possible ways of the house heating and water warming systems, such as heating by electric power, by gas, by solid fuel or the centrally distributed heating. Then the thesis concentrates on heat pumps. There are described various types of heat pumps, also their advantages and disadvantages. There were chosen four main types of heat pumps – air/water, air/air, water/water and earth/water – and with each type there’s constructed a plan for a low-energy house heating. This house is located in Vyškov and there’s thermal loss of 6 kWh and water-warming of a capacity of 260 l per day. At last there were used economical calculations, which shown, that the water/water heat pump has the shortest return rate in comparison with a gas-using heating system – 5 years. Considering the lifespan of the heat pumps – 10-20 years – all the heat pumps are profitable except for the air/air heat pump. The investment in this heat pump doesn’t return.
|