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Thermoelectric Generators for Micro-CHP Units
Brázdil, Marian ; Navrátil, Jiří (referee) ; Masaryk, Michal (referee) ; Pospíšil, Jiří (advisor)
Small domestic hot water boilers burning solid fuels represent a significant source of air pollu-tion. It is therefore an effort to increase their combustion efficiency and to reduce the produc-tion of harmful emissions. For this reason, the operation of older and currently unsatisfactory types of household boilers has been legally restricted. Preferred types of boilers are low-emission boilers, especially automatic or gasification boilers. Most of them, however, in compar-ison with previous types of boilers, also require connection to the electricity grid. If there is a long-term failure in electricity grid, the operation of newer boiler types is limited. Wood and coal gasification boilers are currently available on the market and can be operated even in the event of a power failure, but only in heating systems with natural water circulation. In heating systems with forced water circulation, these boilers, fireplaces or fireplace inserts with hot-water heat exchangers cannot be operated without external battery supply in the event of a power failure. The dissertation thesis therefore deals with the question of whether it would be possible by thermoelectric conversion of waste heat of flue gases of small-scale low-emission combustion hot water domestic boilers to obtain sufficient electricity, to power supply their circulation pumps and to ensure operation in systems with forced water circulation independently of elec-tricity supply from the grid. In order to answer this question, a simulation tool predicting the power parameters of ther-moelectric generators was created. Compared to previously published works, the calculations and simulations include the influence of the generator on the boiler flue gas functionality. To verify the simulation tool, an experimental thermoelectric generator was built using the waste heat of the flue gas of an automatic hot water boiler for wood pellets. In addition to this genera-tor, there was also created an experimental thermoelectric fireplace insert and other equipment related to these experiments.
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A test setup for thermal cycling of thermoelectric modules
Preisler, Lukáš ; Kudela, Libor (referee) ; Brázdil, Marian (advisor)
The present work is focused on thermoelectric modules and testing modes. Failures of thermoelectric modules occur due to the cyclic thermal stress in real applications and their power parameters decrease. Hence an experimental study of thermoelectric modules was executed, which measured parameters of thermoelectric modules and thermal cycling testing methods. In the practical part of this document, the thermal cycling conditions of thermoelectric modules were set-based on the previously stated study. A bipolar-pulse load in range +3,0 V and 3,0 V was proposed alternating after 90 seconds. For comparison of the modules among producers 200 cycles will be made. According to the cycling conditions, construction adjustments of current laboratory testing platform are proposed. The current platform is currently set to measure parameters of thermoelectric modules and is not for cycling load testing.
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Application of MEMS technology in the field of thermoelectric generators
Janák, Luděk ; Brázdil, Marian (referee) ; Ančík, Zdeněk (advisor)
Práce je zaměřena na moderní oblast využití MEMS technologií v oblasti termoelektrických generátorů. Úvodem jsou diskutovány základní principy konstrukce a výroby MEMS TEG modulů. Praktická část práce sestává z ověření parametrů komerčního MEMS TEG modulu měřením a jeho simulace. Simulace je provedena pomocí MATLAB/Simulink i analytických metod. V závěru práce je na základě získaných poznatků provedeno zhodnocení využití metod „thermal energy harvesting” v oblasti letecké techniky.
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A test setup for thermal cycling of thermoelectric modules
Preisler, Lukáš ; Kudela, Libor (referee) ; Brázdil, Marian (advisor)
The present work is focused on thermoelectric modules and testing modes. Failures of thermoelectric modules occur due to the cyclic thermal stress in real applications and their power parameters decrease. Hence an experimental study of thermoelectric modules was executed, which measured parameters of thermoelectric modules and thermal cycling testing methods. In the practical part of this document, the thermal cycling conditions of thermoelectric modules were set-based on the previously stated study. A bipolar-pulse load in range +3,0 V and 3,0 V was proposed alternating after 90 seconds. For comparison of the modules among producers 200 cycles will be made. According to the cycling conditions, construction adjustments of current laboratory testing platform are proposed. The current platform is currently set to measure parameters of thermoelectric modules and is not for cycling load testing.
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|
|
Thermoelectric Generators for Micro-CHP Units
Brázdil, Marian ; Navrátil, Jiří (referee) ; Masaryk, Michal (referee) ; Pospíšil, Jiří (advisor)
Small domestic hot water boilers burning solid fuels represent a significant source of air pollu-tion. It is therefore an effort to increase their combustion efficiency and to reduce the produc-tion of harmful emissions. For this reason, the operation of older and currently unsatisfactory types of household boilers has been legally restricted. Preferred types of boilers are low-emission boilers, especially automatic or gasification boilers. Most of them, however, in compar-ison with previous types of boilers, also require connection to the electricity grid. If there is a long-term failure in electricity grid, the operation of newer boiler types is limited. Wood and coal gasification boilers are currently available on the market and can be operated even in the event of a power failure, but only in heating systems with natural water circulation. In heating systems with forced water circulation, these boilers, fireplaces or fireplace inserts with hot-water heat exchangers cannot be operated without external battery supply in the event of a power failure. The dissertation thesis therefore deals with the question of whether it would be possible by thermoelectric conversion of waste heat of flue gases of small-scale low-emission combustion hot water domestic boilers to obtain sufficient electricity, to power supply their circulation pumps and to ensure operation in systems with forced water circulation independently of elec-tricity supply from the grid. In order to answer this question, a simulation tool predicting the power parameters of ther-moelectric generators was created. Compared to previously published works, the calculations and simulations include the influence of the generator on the boiler flue gas functionality. To verify the simulation tool, an experimental thermoelectric generator was built using the waste heat of the flue gas of an automatic hot water boiler for wood pellets. In addition to this genera-tor, there was also created an experimental thermoelectric fireplace insert and other equipment related to these experiments.
|
|
|
Application of MEMS technology in the field of thermoelectric generators
Janák, Luděk ; Brázdil, Marian (referee) ; Ančík, Zdeněk (advisor)
Práce je zaměřena na moderní oblast využití MEMS technologií v oblasti termoelektrických generátorů. Úvodem jsou diskutovány základní principy konstrukce a výroby MEMS TEG modulů. Praktická část práce sestává z ověření parametrů komerčního MEMS TEG modulu měřením a jeho simulace. Simulace je provedena pomocí MATLAB/Simulink i analytických metod. V závěru práce je na základě získaných poznatků provedeno zhodnocení využití metod „thermal energy harvesting” v oblasti letecké techniky.
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