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Research of Systems for Providing the Quality of the Environment in the Car Cabin
Šíp, Jan ; Kavička, František (referee) ; Volavý, Jaroslav (referee) ; Lízal, František (advisor)
Optimal conditions of indoor environmental quality, especially thermal comfort and indoor air quality, are important because they lead to the active safety of passengers. Long-term exposure to inconvenient temperatures may cause thermal stress and negatively affects the driver’s cognitive functions. These include important abilities of drivers, such as concentration, vigilance, speed of decision-making and others. The inappropriate temperature in the cabin is one of the most dangerous factors causing car crashes. Air indoor quality is negatively affected by exhaust gases or particles from tire wear, which enter the car cabin during ventilation. This can be prevented by using an air recirculation system which does not supply outside air, but it is a closed circuit. This mode, however, causes high CO2 concentration in the cabin which can lead to excessive fatigue. This thesis deals with the influence of different ventilation systems on indoor environmental quality, i. e. thermal comfort and indoor air quality. A partial factor of thermal comfort is the flow field which was investigated downstream of a benchmark automotive vent. CFD was applied to determine the flow field downstream of a vent. The results were validated by experimental data acquired by Constant Temperature Anemometry. CFD has been also used for the evaluation of the thermal comfort of three novel ventilation systems (mixing, ceiling and floor ventilation). The results were validated by experimental data acquired by thermal manikin and climate chamber. Indoor air quality has been evaluated based on the Age of Air. The analytical empirical equation by Rajaratnam can be successfully used also to determine the throw of the jet, which is favorable, especially in light of the fact that both computational methods were not very accurate in velocity decay predictions. The Large Eddy Simulation and Reynolds-averaged Navier–Stokes method are suitable for evaluating the flow field downstream of the automotive vent. The diagrams of comfort zones were evaluated for all regimes based on equivalent temperatures. The best performance in terms of the highest level of human comfort was achieved by the ceiling ventilation in the summer conditions and by the floor ventilation in the winter conditions. From the point of view of the Age of Air, the ceiling air ventilation system is the most suitable for the winter conditions. In the summer conditions the Age of Air values for individual air ventilation concepts are very similar for both interior types.
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EV vehicle cabin thermal management strategy in hot and cold climates
Matušková, Lucie ; Charvát, Pavel (referee) ; Fišer, Jan (advisor)
The goal of the work is to conduct an experiment to measure the temperature at which optimal thermal comfort is achieved. The experiment is carried out in a climate chamber, where constant climatic conditions acting on the vehicle can be ensured. The iHVAC measuring system is used to measure thermal comfort. Then to compare the values with the previous measurement that took place for other vehicles. Part of the work is devoted to research that describe the issue of thermal management of vehicles.
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Ventilated protective clothing for healthcare staff in contaminated environments
Štenclová, Kristýna ; Kopečková, Barbora (referee) ; Fišer, Jan (advisor)
Focus of the masters thesis is experimental verification of cooling effect of ambient air stream directed under a protective clothing of a human. The first part is a review of literature encompassing concepts related to thermal comfort and heat transfer. Possibilities of cooling a human who is moving in high ambient temperature environment are introduced in this part. The second part is focused on hypotheses devised and experiments performed. The last part is focused on results of the experiments and their comparison with an experiment described in literature.
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Thermal comfort of passengers at public transport stops
Junga, Petr ; Počinková, Marcela (referee) ; Rubinová, Olga (advisor)
This diploma thesis focuses on the evaluation of the thermal comfort of passengers at public transport stops, in the shelters of public transport, which are an integral part of urban technical equipment. This topic is gaining in importance especially with regard to climate change and related with increasing frequency of extreme weather events. First part of the diploma thesis is the theoretical part, dealing with public transport shelters from various theoretical points of view. The practical part of the diploma theses deals with experimental measurements of selected physical quantities in the interior and exterior of eleven public transport shelters in the city of Brno, during the six months of 2020 (cold and warm periods). The facts found by experimental measurements for individual shelters are compared and evaluated, with the final selection of the optimal model of the technical solution of the shelter.
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Design of heating of retirement home
Kouřilová, Klára ; Vyhlídalová, Karolína (referee) ; Horká, Lucie (advisor)
The main aim of this bachelor thesis is design of a heating system of the retirement home. The theoretical part deals with ensuring of thermal comfort and possibilities of building temperature regulation. The second part of this thesis, the calculation part, includes design of panel radiators, dimensioning of heating system, design of hot water preparation and design of heat source. As the heat source is chosen gas condensing boilers for heating system and hot water system. The third part contains documentation for construction of heating system.
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Assesment of the Thermal Environment in Vehicular Cabins
Fojtlín, Miloš ; Khoury, Roch El (referee) ; Havenith, George (referee) ; Jícha, Miroslav (advisor)
Ľudia žijúci vo vyspelých krajinách trávia väčšinu svojho života vo vnútorných prostrediach budov alebo dopravných prostriedkov. Z tohto dôvodu, záujem o výskum kvality vnútorných prostredím rastie, pričom hlavný dôraz je kladený na oblasti výskumu ľudského zdravia, produktivity a komfortu. Jedným z faktorov ovplyvňujúci kvalitu prostredí je ich tepelný aspekt, ktorý je najčastejšie popísaný teplotou vzduchu, radiačnou teplotou, vlhkosťou vzduchu a rýchlosťou prúdenia vzdu-chu. Zatiaľ čo tieto parametre je možné riadiť systémom pre vykurovanie, vetranie a klimatizáciu nezávisle na počasí, takéto zariadenia sa podieľajú na vysokej spotrebe energie a značnej uhlíkovej stope. V prostediach kabín áut a dopravných prostriedkov je riadenie parametrov tepelného prostredia komplikované z dôvodu ich asymetrickej a časovo premenlivej povahy. Táto situácia je obzvlášť kritická vo vozidlách na elektrický pohon s vlastnou batériou, kde je energia na úpravu vnútornej mikroklímy čerpaná na úkor dojazdu vozidla. Pre uvedené dôvody sa hľadajú nové, en-ergeticky účinnejšie spôsoby pre úpravu tepelných prostredí a zabezpečenia tepelného komfortu. Jedným z potenciálnych riešení sú zariadenia dodávajúce človeku teplo alebo chlad lokálne, ako napríklad vyhrievané a vetrané sedadlá a sálavé panely. Vzhľadom na to, že experimentálny výskum vnútorných prostredí je náročný s ohľadom na čas a potrebné vybavenie, trendy výskumu vplyvov takýchto zariadení na človeka smerujú k optimalizačným úlohám vo virtuálnych prostrediach pomocou modelov ľudksej termofyziológie a tepelného pocitu/komfortu. Avšak pre spoľahlivé výsledky modelovania sú potrebné presné vstupné parametre definujúce prostredie, odev, vplyv povrchov v kontakte s človekom (napríklad sedadlá) a pôsobenie systémov na lokálnu úpravu mikroklímy. Cieľom tejto dizertačnej práce je vytvorenie metodológie na hodnotenie tepelných prostredí v kabínach automobilov s ohľadom na pozíciu v sede a využitím technológii na lokálnu úpravu tepelných prostredí. Jedným z požiadavkov na takúto metodológiu je jej aplikovateľnosť vo virtuálnych ale aj reálnych prostrediach. V prípade hodnotenia reálnych prostredí, cieľom je vytvorenie demonštrátora, ktorý by bol využiteľný ako spätná väzba pre riadenie systémov pre úpravu mikroklímy na základe požadovaného tepeleného pocitu. Validita uvedenej metodológie bola demonštrovaná v typických podmienkach kabín automobilov (5–41 °C) a poznatky z tejto práce sú prenesiteľné do širokého spektra inžinierkych aplikácii. V oblasti osobnej dopravy a pracovných prostredí s vyššou tepelnou záťažou je táto metóda užitočná pre identifikáciu možných zdrojov diskomfortu. Navyše je táto metóda vhodná i pre rýchlo rastúci segment elektrických vozidiel, kde je možné sledovať tok energie potrebnej na dosiahnutie určitej úrovne komfortu a riešenie optimalizačných úloh za účelom úspory energie a predĺženie dojazdu. Obdobné aplikácie možno nájsť i v budovách a prostrediach s podobnými charakteristikami.
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Heating of apartment buildings
Diatel, Jakub ; Horká, Lucie (referee) ; Počinková, Marcela (advisor)
The topic of this diploma thesis is heating of apartment buildings, where an attention was focused on thermal comfort in heated rooms. The first theoretical part brings results of CFD simulations which compare radiators with floor heating. The second part consits of practical application o the given building. There are two options in this project - heating by radiators or floor heating. The third part describes two experiments - measurement of indoor environment in two rooms and measurement of gas consumption in apartment buildings with different heating concepts. In the last part the mean radiant temperature is simulated. There are compared different kind of heating, which have impact to distribution of mean radiant temperature in the room. The personal software was created for deeper understanding of mean radiant temperature.
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Local Control of Seat Ventilation and Its Impact on Human Thermal Comfort
Matuška, Jaroslav ; Toma, Róbert (referee) ; Fišer, Jan (advisor)
Diplomová práce je zaměřena na měření ventilovaného sedadla s ohledem na tepelný komfort člověka. Popisuje a shrnuje tepelný přenos lidského těla s okolím a termoregulaci člověka. Dále zachycuje a zhodnocuje vybrané přístupy hodnocení tepelného komfortu. Zabývá se komplexním přehledem tepelně komfortních jednotek v automobilu. Představuje použitou metodu měření tepelného komfortu u ventilovaného sedadla, načež analyzuje a vyhodnocuje jednotlivá získaná data.
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