This study analyzed the ability of computational fluid dynamic software to accurately predict the flow coefficient of three bottom-load ball valves to develop a design which can accurately control flow rate.

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Main issue of this master´s thesis deals with high-frequency pulsations caused by cavitating hydraulic components (in this case nozzle and throttle valve). In first measurement on the nozzle was not a high-frequency sensor set in the way, so the evaluation was incorrect. After re-setting of the way was the nozzle measured again and the pulsations were evaluated correct this time. During the last measurement was the sensor located behind the throttle valve, which was with gradual opening and cavitation treatment measured. Resulting dependencies worked out on time dependence. A special mathematical method, Fourier transformation, was used. It transformed pressure amplitudes into frequency dependence. Evaluation of dependecies is the basic step for frequency band assesment, in which the cavitation on particular components happens.

The thesis contains basic information about propeler turbines. It deals with the correct location in the fountain so as to ensure the highest possible performance. Part of the work is devoted to the all-weather resulting blade to blade channels and their impact on the room is filled with diffuser.

Submitted by Silvana Teresinha Dornelles Studzinski (sstudzinski) on 2017-02-08T14:37:06Z No. of bitstreams: 1 Henrique Zenker dos Santos_.pdf: 9480964 bytes, checksum: 5a3a14f9704ce1135e84db57590283a7 (MD5) / Made available in DSpace on 2017-02-08T14:37:06Z (GMT). No. of bitstreams: 1 Henrique Zenker dos Santos_.pdf: 9480964 bytes, checksum: 5a3a14f9704ce1135e84db57590283a7 (MD5) Previous issue date: 2016-10-21 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Países desenvolvidos apresentam crescimento contínuo nas taxas globais de consumo de energia. Um dos fatores preponderantes está relacionado ao uso de condicionadores de ar para manutenção das condições de conforto no interior de edificações, onde tal parcela já atinge valores de consumo superiores aos dos setores de indústria e transporte. Sabe-se que o consumo devido ao condicionamento de ar afeta diretamente o desempenho energético e ambiental de uma edificação e, por conseguinte, a qualidade de habitação e de vida dos usuários. No Brasil este processo ocasiona um vertiginoso incremento nos gastos públicos, com inúmeras consequências de ordem econômica e social. Dados do Ministério de Minas e Energia indicam que 20% da energia consumida no país é destinada ao abastecimento de residências. Cenário este que tende a evoluir devido aos constantes lançamentos do mercado imobiliário, derivativos de planos habitacionais estimulados pelo governo federal (como o Minha Casa Minha Vida), em decorrência do déficit habitacional registrado no país. Atrelado a isso observa-se o baixo padrão construtivo das edificações e o emprego de materiais e esquadrias de qualidade igualmente diminutas, que acarretam em ineficiências de carga térmica. A taxa de infiltração em uma edificação é regida pela relação estabelecida por uma equação de lei de potência, caracterizada pela presença de um coeficiente de escoamento “C” e um expoente de escoamento “n” (geralmente da ordem de 0,667 [-]). Esta dissertação apresenta, para uma esquadria de alumínio, modelo de correr, o coeficiente de escoamento C = 0,028 [dm³/s.m.Pan] e o expoente de escoamento “n” 0,552 [-]. Para uma esquadria de PVC, modelo integrado, o coeficiente de escoamento C = 0,022 [dm³/s.m.Pan] e o expoente de escoamento “n” 0,605 [-]. / Developed countries have continued growth in global energy consumption rates. One of the most important factors is related to the use of air conditioners to the comfort conditions inside buildings’ maintenance, which such a part already reaches consumption values higher than the industry and transportation sectors. It is known that consumption due to air conditioning directly affects the energy and environmental performance of a building and therefore the house’s quality and the people’s life. In Brazil, this process leads to a big increase in public spending, with many consequences of economic and social order. Information from the Ministry of Mines and Energy indicate that 20% of the energy consumed in the country is used for supplying homes. This scenario tends to evolve due to the constant housing market releases, derived from housing plans stimulated by the federal government (such as “Minha Casa Minha vida”), in consequence of the housing deficit registered in the country. Related to this, it is observed the low construction standards of buildings and the use of materials and frames of low quality that lead to thermal load inefficiencies. Engineers and architects spend a part of their activities in creating scenarios for evaluating the thermal load calculation and vulnerability due to the influence caused by air infiltration into the environment. The infiltration rate of a building is managed by the established relationship by a power law equation, which is characterized by a flow coefficient "C" and a flow exponent "n" (usually on the value of 0.667 [-]). This work shows for an aluminum window, sliding template, the flow coefficient C = 0.028 [dm³/s.m.Pan] and the flow exponent "n" 0.552 [-]. For PVC window, integrated model, the flow coefficient C = 0.022 [dm³/s.m.Pan] and the exponent flow "n" 0.605 [-].

In this diploma thesis called Water column separation under the hydraulic turbine runner during unsteady operating regimes are solved the pressure pulsations of the reverse water hamer. In the thesis is deduced a mathematical relationship of elaboration the numerice model which is based on equations of continuity and equations of forces equilibrium. Numerical model is created in MS Excel uses for computation the numerical method Lax-Wendrof that allows consideration of variable sound speed as function of static pressure and allows variable lenght step in computation domain. Reverse water hammer is in the thesis solved with consideration of rotating flow behind shut-off valve, where we expect forming of vortex rope. This situation can be applied on the closing water turbine which has vertex rope under turbine runner. Specifically for this thesis was carried out the experiment of the reverse water hammer. Constants going into numerical solution are optimalized with using experiment and pressure pulsation are compared between numerical solution and experiment.

The theme of this diploma thesis is fittings of heating systems and it is divided into three parts. The first part deals with this topic on theoretical level. In the second part, there is a calculations and drawings that deals with heating and water heating of the apartment building in Uherské Hradiště. This part is solved in two variants concerning hydraulic balancing and regulation of the heating system. The last part of the thesis is an experimental solution and processing of pressure loss results of selected valves. These results are compared with the values reported by the manufactures of the valve.

This diploma thesis deals with pressure losses in heating systems. The diploma thesis is divided into three sections. The first part is theoretical and deals with the occurrence of pressure losses. It discusses the properties of the fluid that affect pressure losses. It also deals with hydrodynamic phenomena, flow distribution, pressure loss distribution and its calculations. The aim of the second part, which is practical, was to create a heating project for a selected object. The object is a two-floor kindergarten building located in Velké Němčice. For this project, two heating variants were created. For the first variant, radiators and heating benches were designed and for the second variant, underfloor heating was installed in the building. The goal was to use a source which will gain heat mainly from renewable sources, so the air / water heat pump was chosen as the source of heat production. The project ends with a technical report. The third part of the thesis is dedicated to an experiment which purpose was to find out how the pressure losses of the connecting pieces are reacting to the change with the change of the heating water conditions (flow, temperature). Alongside, two pipes were created which differed in the type of connecting pieces so it allowed to compare how their pressure losses differ. Both pipes were connected by radial pressing, but the fittings differed in the quality of the brass, and therefore in the construction. Also, part of the experimental section of the diploma thesis is a description of the course of radial pressing of fittings from the Herz company.