Master Degree / Yüksek Lisans Tezleri

Permanent URI for this collectionhttps://hdl.handle.net/11147/3008

Browse

Filters

2003 - 200912010 - 201942020 - 20243

Settings

Language: search.filters.language.enSubject: search.filters.subject.Energy consumption

Search Results

Now showing 1 - 8 of 8
  • Master Thesis
    Development of a Dishwasher Drying System That Utilizes Wastewater Thermal Energy and Experimental Investigation of Its Performance
    (01. Izmir Institute of Technology, 2024) Dalbudak, Uğur Doğan Can; Çetkin, Erdal
    Ev tipi Bulaşık makineleri, girdi olarak elektrik ve suyu kullanarak yıkama işlemi yapan ve hane halkının konforunu arttıran ev aletlerindendir. Bir yıkama çevriminde kullanılan elektriğin 70% ile 90% değişen kısmı suyu ısıtmak için kullanılır. Yıkama sonucunda oluşan 45°C-60°C sıcaklık aralığında olabilen atık su, kullanılmadan gidere boşaltılır. Bu tezde, atık suyun ısıl enerjisinden faydalanmak amacıyla termal enerji deposu (TED) geliştirilmiştir. TED üzerine, atık su ile ısıl etkileşimde olacak şekilde ek bir hava kanalı eklenmiştir. Bu kanala bağlı fan yardımıyla dış ortamdan 23°C sıcaklık ve 55% bağıl neme sahip hava kanaldan geçerken atık su enerjisi ile ısınıp yıkama kabinine gönderilmektedir. Sıcaklığı artan havanın nem taşıma kapasitesi artmakla beraber kabine göre bağıl nemi de düşük seviyelerde olduğu için kurutma performansını iyileştirmesi sağlanmıştır. TED ile ısıl etkileşimde bulunan hava kanalında kanat yapısına bağlı olarak ısı geçişini arttırmak için kanal içerisinde 5 farklı tipte kanat yapısı tasarlanarak hesaplamalı akışkanlar dinamiği ile analizi yapılmıştır. İlk olarak kanat yapılarının akış direncini ne yönde etkiledikleri araştırılarak hava çıkış debileri karşılaştırılmıştır. Sonrasında ise, kurutma evresinindeki başlangıç koşulları ile zamana bağlı çözüm yapılarak, kanatların ısı geçişi üzerine etkileri değerlendirilmiştir. En verimli sonucu veren kanal boyu uzanan kanat tasarımı ile prototip üretilmiştir. Kurutma performansı deneyleri prototip TED ile bulaşık makinesi EN 60436 standardına göre yapılmıştır. Çıkan sonuca göre B enerji sınıfı (0.595 kWh/çevrim) olan bir Bulaşık makinesine geliştirilen TED sistemi entegre edildiğinde, A sınıfına (0.544 kWh/çevrim) ulaşılmıştır.
  • Master Thesis
    Multi-Objective Optimization of Residential Buildings for Improving Indoor Thermal Comfort While Reducing Energy Consumption
    (01. Izmir Institute of Technology, 2024) Özyılmaz, Ece; Arsan, Zeynep Durmuş
    Son yıllarda yön gözetmeksizin yüksek cam-cephe oranı ile tasarlanan konut yapıları yaygınlaşmaktadır. Bu tasarım çözümleri başta aşırı ısınma olmak üzere, ısıl rahatsızlık ile yüksek enerji tüketimi ve soğutma yükü gibi sorunlara yol açmaktadır. Bu çalışmanın ana amacı, mevcut bir konut binasının enerji tüketimi ve ısıl konforu üzerinde en yüksek ve en düşük hassasiyete sahip tasarım değişkenlerini belirlemek ve enerji tüketimini azaltırken ısıl konforu iyileştiren optimum yenileme çözümlerini bulmaktır. Akdeniz iklim bölgesinde yer alan, 2019 yılında inşa edilmiş, güneye cepheli bir konut bloğu örnek olarak seçilmiştir. DesignBuilder'da oluşturulan model, saatlik iç mekan sıcaklık izleme verilerine göre sekiz aylık bir dönem için kalibre edilmiştir. Çalışma kapsamında belirsizlik ve duyarlılık analizi yapılmış, analiz sonuçlarına göre duyarlılığı düşük bulunan değişkenler dikkate alınmamıştır. NSGA-II algoritması kullanılmıştır. Altı adet iyileştirme senaryosu tanımlanmıştır: bina zarfı özelliklerini değerlendiren pasif olanlar, HVAC sistemi özelliklerini değerlendiren aktif olanlar ve ilk iki senaryoda alınan tüm tasarım değişkenlerini değerlendiren senaryolar. İlk üç senaryoda enerji tüketimini ve konforsuz saatleri en aza indirmek hedeflenirken, diğer üç senaryoda soğutma yükünü ve konforsuz saatleri en aza indirmek amaçlanmaktadır. Duyarlılık analizi sonuçlarına göre soğutma-ısıtma ayar noktası, gölgeleme tipi, sızma oranı, pencere duvar oranları her iki amaç fonksiyonu için de yüksek hassasiyete sahip değişkenlerdir. Isıtma sistemi çalışma takvimi, soğutma sistemi performans katsayısı, ısıtma sistemi verimliliği, iç duvar tipi ve pencere çerçeve tipi değişkenlerinin duyarlılığının düşük olduğu sonucuna ulaşılmıştır. Üçüncü ve altıncı senaryolarda her iki amaç fonksiyonunun da temel duruma göre azaldığı optimum çözümler bulunmuştur. Bu senaryolarda, aşırı ısınma problemi hem aktif hem de pasif çözümler değerlendirilerek çözülmüştür.
  • Master Thesis
    Investigation of Windshield Defogging and Defrosting Designs To Decrease Energy Consumption in Vehicles
    (01. Izmir Institute of Technology, 2023) Ediz, Fatih; Çetkin, Erdal
    Fogging and icing of windshields are general problems that affect driving safety and energy consumption. The aim of this study is to improve the truck windshield defogging system and reduce energy consumption. Firstly, we investigated the effects of vent position and width relative to the glass. In the first stage, we performed analysis on the truck xz plane (2D). We preferred this method to quickly see the effect of vent changes. In the second stage, we applied the modification parameters to the 3D duct model. In both studies, we determined that the independent variables had a statistically significant effect on the dependent variable and determined the parameters with the highest desirability value by using the Analysis of Variance method. Secondly, we added various separators to the duct model. We investigated the total mass flow rate coming to the driver's side with total pressure drop. In this thesis, we used the Eulerian Wall Film (EWF) Model to model the defogging phenomenon on windshields. In the EWF model, the wall film is treated as a separate fluid phase, and the conservation equations for mass, momentum, and energy are solved separately for each fluid phase. As a result, we applied the obtained data to the current design. Windshield defogging performance has improved in the optimization model. The average film thickness in region A decreased by 8.2% compared to the current model, while the average film thickness in region B decreased by 48.1%.
  • Master Thesis
    Hydraulic Design Optimization and Performance Evaluation for a Dishwasher
    (Izmir Institute of Technology, 2019) Erik, Ömer Berhan; Çetkin, Erdal
    Hydraulic designs of dishwashers with 12 (2 baskets) and 15 (3 baskets) place settings with diverter which distributes the water to bottom and upper spray arms separately were analyzed. First, both hydraulic systems were modeled analytically, so continuous and local losses were calculated based on them. Besides, operating point of systems were determined based on the curve of the pump and head loss. All parameters were also verified by experimental tests. An asynchronous circulation pump (fixed pump rpm and outlet pressure) with the same hydraulic outlet pressure is used in both products. Hydraulic design is evaluated with parameters obtained from the analytical model and then the design of equipment along the hydraulic path was improved. Once parameters improving the designs are determined, modified parts were analyzed numerically with finite volume method. The results were also validated with experimental studies. Lastly, prototype with improved design parameters was produced and installed on a dishwasher. Dishwasher performance index was calculated according to IEC standards to see the effect of new design on dishwasher washing performance. The results show that the energy requirement decreases 25% whereas performance index stays the same.
  • Master Thesis
    Effect of Natural Wall Materials on Energy Consumption in Continental and Mediterranean Climates
    (Izmir Institute of Technology, 2019) Yöney, Ekin Gamze; İlal, Mustafa Emre; İlal, Mustafa Emre
    Concern on earth and other natural building materials has been increased by rise of energy shortage and environmental problems. Not only the speed, quality and standardization in the production process of natural building materials should be improved, but also energy consumption of buildings constructed with these materials should be on acceptable levels in order to expend their usage. This study investigates the relationship between natural wall materials and energy consumption on two adobe buildings from Continental and Mediterranean climates. Totally 20 different wall options, composed of adobe, vertical hollow brick, limestone, hempcrete and strawbale with 0.30- and 0.50-meter thickness without and with flax thermal insulation material are tested with different combinations of direction and climate. The digital models of case buildings in Continental and Mediterranean climates are created to examine the question of in what climate and which direction a wall material is appropriate for energy efficient design. Consequently, strawbale enables the minimum annual energy consumption both for Mediterranean and Continental climates, while adobe shows better energy performance in summer period of Continental climate. Besides, it is observed that the energy consumption for cooling in case building of Mediterranean climate is 10 times more than of Continental one for whatever material is tested. The quantitative research conducted with different natural wall materials makes it a logical choice in terms of opening the path of industrialization that is supported by the aim of this thesis.
  • Master Thesis
    Improvement of the Thermal Performance of an Aluminium Window Frame With Cfd Analysis
    (Izmir Institute of Technology, 2019) Gökçen, Gökçe; Başaran, Tahsin
    Most of the primary energy used in the world belongs to fossil fuels. Energyefficient activities are carried out in many different sectors in order to prevent the depletion of the reserves of these resources. The building sector is one of them and many different studies are being carried out to reduce the energy consumed in the buildings. Windows are the main unit of heat losses and gains in buildings. In literature, the main reasons for heat losses through windows are usually stated as glass units due to their large areas and relatively higher overall heat transfer coefficient. However, windows frames are as important as glass units because they also have higher heat transfer. Since the most commonly used material in window frames, which is aluminium, has the highest thermal conductivity value, this topic should be investigated. In this study, two different strategies are presented to improve the thermal transmittance of an aluminium frame without changing the frame geometry. The first strategy presented is the improvement of the gasket and thermal break materials in which high thermal conductivity materials are used which have a considerable impact on the thermal performance of aluminium window frames. The second strategy is to fill the cavities in aluminium profiles with polyurethane foam in order to reduce convection effects. Two dimensional CFD simulations of the aluminium window frame, modelled with information from the manufacturer, were used to investigate these improvement strategies. As a result of the study, the importance of thermal break and gasket materials used in the aluminium window frame has been seen and the thermal conductivity of these materials has a considerable effect on the thermal performance of the windows. Moreover, the polyurethane foam filled air cavities in the aluminium frame have positively affected the thermal performance of window as proposed and %29.44 improvements occurred.
  • Master Thesis
    Effectiveness in Space and Energy Utilization in Hvac System Selection
    (Izmir Institute of Technology, 2019) Elbiz, Gizem; Başaran, Tahsin
    In Turkey, energy consumption for heating constitutes an important part of the total energy consumed. The choice of heating system and the preferences in the use of related energy sources, excessive energy consumption and environmental impact cause high costs and significant area losses. A large number of parameters must be evaluated for the correct system selection. These parameters determine the installation cost of the system, heating and cooling loads during the construction period, and the environmental impact of energy consumption. This study aims to obtain the most economical and environmental friendly energy resource in a housing structure and accordingly, heating system and the system spatial value. The use of fossil fuels such as coal, fuel oil and natural gas and the geothermal energy as a renewable energy source are planned to be investigated. The analysis was carried out on how the climate conditions and economic values of the provinces of İzmir, Balıkesir, Kütahya and Ağrı, which are located in different climatic regions will be effected and where direct use of geothermal energy is concerned, will affect the results of the different system usage. Life Cycle Cost assessment was performed to investigate the relationship between the initial investment in a housing structure and the use of energy source and system selection. Geothermal energy is the best source of energy both for installation and renewal and for fuel consumption and environmental purposes. Geothermal heat exchangers selected for the source take up 36 times less space than coal boilers, and the economic reflection of this area is approximate 8000 if given the example of İzmir province. While considering the environmental impacts, CO2 emissions of geothermal energy are 15 times less than natural gas and 50 times less than coal.
  • Master Thesis
    Optimization of Hvac Control Strategies by Building Management Systems Case Study: Özdilek Shopping Center
    (Izmir Institute of Technology, 2003) Canbay, Çağlar Selçuk; Gökçen Akkurt, Gülden
    HVAC systems in buildings must be complemented with a good control scheme to maintain comfort under any load conditions. Efficient HVAC control is often the most costeffective option to improve the energy efficiency of a building. However, HVAC processes are nonlinear, and characteristics change on a seasonal basis so the effect of changing the control strategy is usually difficult to predict.Aim of this thesis is to reduce energy consumptions by defining new HVAC control strategies and tuning control loops in Ozdilek Shopping Center "OSC". To investigate the potential for energy savings and to redefine control scenarios, an energy audit was carried out in "OSC". According to these studies new strategies are implemented by the help of existing building management system "BMS" without making any investment.Performance indices were calculated and compared with the accepted standards. Then normalized performance indices are calculated to reach out a better understanding of the buildings' efficiency.