Energy Systems Engineering / Enerji Sistemleri Mühendisliği

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  • Article
    Citation - WoS: 30
    Citation - Scopus: 30
    A Novel Data-Driven Model for the Effect of Mood State on Thermal Sensation
    (MDPI, 2023) Turhan, Cihan; Özbey, Mehmet Furkan; Ceter, Aydın Ege; Gökçen Akkurt, Gülden
    Thermal comfort has an important role in human life, considering that people spend most of their lives in indoor environments. However, the necessity of ensuring the thermal comfort of these people presents an important problem, calculating the thermal comfort accurately. The assessment of thermal comfort has always been problematic, from past to present, and the studies conducted in this field have indicated that there is a gap between thermal comfort and thermal sensation. Although recent studies have shown an effort to take human psychology into account more extensively, these studies just focused on the physiological responses of the human body under psychological disturbances. On the other hand, the mood state of people is one of the most significant parameters of human psychology. Thus, this paper investigated the effect of occupants' mood states on thermal sensation; furthermore, it introduced a novel Mood State Correction Factor (MSCF) to the existing thermal comfort model. To this aim, experiments were conducted at a mixed-mode building in a university between 15 August 2021 and 15 August 2022. Actual Mean Vote (AMV) and Profile of Mood States (POMS) were used to examine the effect of mood state on thermal sensation. The outcomes of this study showed that in the mood states of very pessimistic and very optimistic, the occupants felt warmer than the calculated one and the MSCFs are calculated as -0.125 and -0.114 for the very pessimistic and very optimistic mood states, respectively. It is worth our time to note that the experiments in this study were conducted during the COVID-19 Global Pandemic and the results of this study could differ in different cultural backgrounds.
  • Article
    Citation - WoS: 15
    Citation - Scopus: 18
    An Integrated Decision-Making Framework for Mitigating the Impact of Urban Heat Islands on Energy Consumption and Thermal Comfort of Residential Buildings
    (MDPI, 2023) Turhan, Cihan; Atalay, Ali Serdar; Gökçen Akkurt, Gülden
    Urban heat island (UHI) is a zone that is significantly warmer than its surrounding rural zones as a result of human activities and rapid and dense urbanization. Excessive air temperature due to the UHI phenomenon affects the energy performance of buildings and human health and contributes to global warming. Knowing that most of the building energy is consumed by residential buildings, therefore, developing a framework to mitigate the impact of the UHI on residential building energy performance is vital. This study develops an integrated framework that combines hybrid micro-climate and building energy performance simulations and multi-criteria decision-making techniques. As a case study, an urban area is analyzed under the Urban GreenUP project funded by the European Union's Horizon 2020 Programme. Four different strategies to mitigate the UHI effect, including the current situation, changing the low-albedo materials with high-albedo ones, nature-based solutions, and changing building facade materials, are investigated with a micro-climatic simulation tool. Then, the output of the strategies, which is potential air temperature, is used in a dynamic building energy simulation software to obtain energy consumption and thermal comfort data of the residential buildings in the case area. Finally, a multi-criteria decision-making model, using real-life criteria, such as total energy consumption, thermal comfort, capital cost, lifetime and installation flexibility, is used to make a decision for decreasing the UHI effect on residential energy performance of buildings. The results showed that applying NBSs, such as green roofs and changing existing trees with high leaf area density ones, have the highest ranking among all mitigation strategies. The output of this study may help urban planners, architects, and engineers in the decision-making processes during the design phase of urban planning.
  • Article
    Citation - WoS: 23
    Citation - Scopus: 27
    The Influence of Meteorological Parameters on Pm10: a Statistical Analysis of an Urban and Rural Environment in İzmir/Turkiye
    (MDPI, 2023) Birim, Necmiye Gulin; Turhan, Cihan; Atalay, Ali Serdar; Gökçen Akkurt, Gülden
    Air pollution is a substantial menace, especially in industrialized urban zones, which affects the balance of the environment, life of vital organisms and human health. Besides the main causes of air pollution such as dense urbanization, poor quality fuels and vehicle emissions, physical environment characteristics play an important role on air quality. Therefore, it is vital to understand the relationship between the characteristics of the natural environment and air quality. This study examines the correlations between the PM10 pollutant data and meteorological parameters such as temperature (T-air), relative humidity (RH), and wind speed (WS) and direction (WD) under the European Union's Horizon 2020 project. Two different zones (Vilayetler Evi as an urban zone and Sasali Natural Life Park as a rural zone) of Izmir Province in Turkiye are used as a case study and the PM10 data is evaluated between 1 January 2017 and 31 December 2021. A one-tailed t-test is used in order to statistically determine the relationships between the PM10 pollutant data and meteorological parameters. As a further study, practical significance of the parameters is investigated via the effect size method and the results show that the RH is found to be the most influencing parameter on the PM10 for both zones, while T-air is found to be statistically non-significant.
  • Research Project
    Yarımada yüksek rüzgar ölçüm direği
    (2019) Gökçen Akkurt, Gülden; Bingöl, Ferhat
    Bu projede iki temel konu çalısılmıstır. (i) Rüzgar enerjisi yatırımları yerinde ölçüm yapma gerekliligine sahiptir. Rüzgar mühendisligi dalında sıkça kullanılan Weibull olasılık dagılımı rüzgarın yüksek ve devamlı oldugu yerlerde kolaylıkla iki parametreli Weibull dagılımına uymaktadır. Ancak, degisken rüzgar kosullarında bu isem adımlarında zorluklar yasanır. Bu çalısmada 101m meteoroloji ölçüm diregi kullanılarak bir çok farklı dagılım metodu test edilmis ve sonuçlar karsılastırılmıstır. (ii) Modelleme ve türbin üstüne gelen gerçek yüklerin hesabında ise kararlılık analizi çalısması önemli bir yer tutmaktadır. Çünkü, atmosferin farklı konuslarına göre logaritmik rüzgar profilinden sapan dikey rüzgar karakteristigi degismekte ve bunun düzgün olarak hesaplanamadıgı durumlarda fazla ya da eksik üretim tahmini yapılmaktadır. Her iki durumda da olusturulan ekonomik model yatırıcmı için sorun çıkarmaktadır. Türkiye'de hali hazırda kurulu 1500'e yakın direk ve daha önce ölçüm yapılmıs olan baska yerlerdeki yine binden fazla direkte kararlılık analizi yapacak bir ölçüm cihazı yapılanması yoktur. Bu projenin ikinci ayagında amacımız kurulan 101m yükseklikteki diregi kullanarak ölçüm cihazı yetersiz direklerde de kararlılık analizi yapabilen bir yöntem gelistirmek ya da hali hazırda var olan modellerin saglamasını yapmaktır.
  • Conference Object
    Citation - Scopus: 1
    Comfort Based Investigation on Historic Libraries for User Satisfaction and Preservation of Paper-Based Collections
    (IOP Publishing, 2021) Turhan, Cihan; Topan, Çağrı; Durmuş Arsan, Zeynep; Göksal Özbalta, Türkan; Gökçen Akkurt, Gülden
    Historic libraries preserve cultural heritage values while housing rare manuscripts and paper-based collections. The collections in the libraries are deteriorated chemically, biologically and mechanically due to inappropriate indoor environment conditions such as temperature and relative humidity fluctuations and microbiological conditions. Apart from preserving vulnerable paper-based collections, accommodating of a considerable thermal comfort level for visitors is essential in historic libraries. The aim of this study is to analyse indoor environment of a historic library in terms of thermal comfort and preventive conservation of paper-based collections. Izmir National Library, built in 1933, is selected as a case study. Indoor air temperature, relative humidity and air velocity in the library were monitored with a one-year measurement campaign. Meanwhile, thermal comfort of the visitors was assessed with PMV/PPD indices and thermal sensation surveys. The results show that high chemical degradation risk is detected in the library while biological and mechanical degradations are in the low risk zone. On the other hand, 87% and 93% of the visitors feel thermally satisfied in heating and cooling seasons, respectively.
  • Article
    Türkiye’nin Farklı İklim Koşullarında Isıl Konfor Sıcaklıklarına Bağlı Olarak Konutların Enerji Performanslarının Değerlendirilmesi
    (2021) Hancıoğlu Kuzgunkaya, Ebru; Yıldırım, Nurdan; Gökçen Akkurt, Gülden
    Isıl konfor, insanın yapısı, yaşı, cinsiyeti gibi kişisel parametrelerin yanı sıra çevresel parametrelere de bağlıdır. Isıtma, soğutma ve havalandırma sistemlerinin çalışma şekli ve dış hava sıcaklıkları ısıl konfor için önemli parametrelerdir. Fanger deneysel çalışmalar sonucu “tahmini ortalama oy (PMV)” olarak adlandırılan bir gösterge oluşturmuş ve PMV=0’ı konfor için en iyi değer olarak belirlemiştir. Bu çalışmada, farklı iklim bölgelerinden dört il seçilerek, her bir il için ısıl konfor sıcaklıkları belirlenmiş ve bu ısıl konfor sıcaklıklarındaki enerji performansları değerlendirilmiştir. Isıtma ve soğutma sistemi için kişisel kontrole izin verilmeyen tam mekanik kontrollü sistem seçilmiş, kesikli ve sürekli rejim için hesaplamalar yapılmıştır. Çalışmada, konfor koşullarının PMV=0 olması durumunda enerji tüketimleri incelenerek iller arasındaki ısıl konfor memnuniyeti ve enerji tüketiminindeki farklılıklar saptanmaya çalışılmıştır. PMV değerlerinin istatistiksel analizinde, İzmir ili için kesikli rejimde çalışmanın sürekli rejime göre daha iyi olmasına rağmen İstanbul için sürekli rejimde konfor koşulları açısından daha iyi sonuçlar alınmıştır. Tüm illerde sürekli rejim uygulandığında birim enerji tüketiminde artış olduğu belirlenmiştir. Sürekli rejim, kesikli rejime göre ısıtma enerji tüketiminde % 4,5-6,2, soğutma enerji tüketiminde ise % 9,1-23,2 daha yüksektir.
  • Article
    Citation - WoS: 58
    Citation - Scopus: 76
    Utilization of Renewable Energy Sources in Desalination of Geothermal Water for Agriculture
    (Elsevier, 2021) Tomaszewska, Barbara; Gökçen Akkurt, Gülden; Kaczmarczyk, Michal; Bujakowski, Wieslaw; Keleş, Nazlı; Jarma, Yakubu A.; Baba, Alper; Bryjak, Marek; Kabay, Nalan
    The agricultural sector, which is highly dependent on water, is urged to build on improved water management practices and explore available options to match supply and demand because of the water scarcity risks and a sustainable and productive agri-food chain. Geothermal water is an energy source used to generate electricity and/or heat. After harnessing its energy, the remaining water can be used as a water source for irrigation following treatment because of its high ionic content. Geothermal fields are mostly located in rural areas where agricultural activities exist. This would be a good match to decrease the transportation cost of irrigation water. The energy demand of the desalination process for agriculture is higher, requiring additional post-treatment processes. Fossil fuels to fulfill the energy requirements are becoming expensive, and greenhouse gas emissions are harmful to the environment. Thus, efforts should be directed towards integrating renewable energy resources into desalination process. This work focuses on presenting a comprehensive review of geothermal water desalination which is powered by renewable energy and provides specific cases from Turkey and Poland. Furthermore, possible new generation renewable energy systems in desalination are introduced, considering their potential application in the desalination of geothermal water for agricultural irrigation.
  • Article
    Isıl Konfor Sıcaklıklarına Bağlı Olarak Bir Konutun Enerji Performansının Değerlendirmesi: Izmir Örneği
    (Sakarya Üniversitesi, 2018) Yıldırım, Nurdan; Kuzgunkaya, Ebru; Gökçen Akkurt, Gülden
    Türkiye’de enerji tüketiminin yaklaşık %34’ü binalarda ve bunun %85 kadarı da ısıtma ve soğutma amaçlı kullanılmaktadır. Binalarda bulunan HVAC sistemlerinin işletme özellikleri, hem binanın ısıl konforunu hem de enerji tüketimlerini doğrudan etkilemektedir. Bu çalışmada, HVAC sistemlerinin işletme şartlarının, ısıl konfor koşulları ile enerji tüketimlerine olan etkisinin belirlenmesi amaçlanmaktadır. Bu amaçla İzmir ilindeki 100 m2’lik bir konut için öngörülen HVAC sisteminin kesikli ve sürekli rejimde, tek ve çift sıcaklık set değerleri ile tam mekanik kontrollü veya doğal havalandırmalı olarak çalıştırılması durumları incelenmiştir. Isıl konfordan olan memnuniyet; Tahmini Ortalama Oy (Predicted Mean Vote - PMV) değeri ile ifade edilmektedir. Bu kapsamda öncelikle, Design Builder yazılımı kullanılarak en iyi duruma karşılık gelen PMV=0’a göre HVAC sisteminin set sıcaklıları belirlenmiştir. Bu sıcaklık set değerlerinin kullanılması ile ele alınan 5 farklı durumda konut için yıllık birim ısıtma/soğutma enerji tüketimleri, birim birincil enerji tüketimi, yıl boyunca ailenin evde bulunduğu saatlerde sağlanan PMV değerleri ve PMV değerlerinin istatistiksel değerlendirilmesi gerçekleştirilmiştir. Elde edilen sonuçlara göre, incelenen 5 durum arasında normal beklenti seviyesinde % 99,6 kümülatif frekans yüzdesi ile ısıl konforu en çok sağlayan tam mekanik kontrollü, sürekli rejim, aylık çift ısıtma/soğutma operatif sıcaklık set değerli durumdur. Tam mekanik kontrollü, kesikli rejim, aylık tek ısıtma/soğutma hava sıcaklığı set değerli durum ise 2,04 kWh/m2/%KF birim memnuniyet enerji tüketimi değeri ile en az enerji tüketen durum olmaktadır.
  • Article
    Citation - WoS: 119
    Citation - Scopus: 141
    Dynamic Thermal and Hygrometric Simulation of Historical Buildings: Critical Factors and Possible Solutions
    (Elsevier, 2020) Gökçen Akkurt, Gülden; Aste, N.; Borderon, J.; Buda, A.; Calzolari, M.; Chung, D.; Turhan, C.
    Building dynamic simulation tools, traditionally used to study the hygrothermal performance of new buildings during the preliminary design steps, have been recently adopted also in historical buildings, as a tool to investigate possible strategies for their conservation and the suitability of energy retrofit scenarios, according to the boundary conditions. However, designers often face with the lack of reliable thermophysical input data for various envelope components as well as with some intrinsic limitations in the simulation models, especially to describe the geometric features and peculiarities of the heritage buildings. This paper attempts to bridge this knowledge gap, providing critical factors and possible solutions to support hygrothermal simulations of historical buildings. The information collected in the present work could be used by researchers, specialists and policy-makers involved in the conservation of building's heritage, who need to address a detailed study of the hygrothermal performance of historical buildings thorugh dynamic simulation tools.
  • Article
    Citation - WoS: 12
    Citation - Scopus: 13
    Assessment of Thermal Comfort Preferences in Mediterranean Climate a University Office Building Case
    (Vinca Inst Nuclear Sci, 2018) Turhan, Cihan; Gökçen Akkurt, Gülden
    This study aims at evaluating the perceived thermal sensation of occupants with respect to thermal comfort standards, ASHRAE 55 and ISO 7730, for office buildings located in Mediterranean climate. A small office building in Izmir Institute of Technology Campus Area, Izmir, Turkey, was chosen as a case building and equipped with measurement devices to assess thermal comfort of occupants with respect to predicted mean vote and actual mean vote. Both objective and subjective measurements were conducted. The former included indoor and outdoor air temperature, mean radiant temperature, relative humidity and air velocity that were used for evaluating the thermal comfort of occupants. Oxygen concentration which can play an additional role in thermal comfort/discomfort, health and productivity of the office occupants, was also measured. Furthermore, occupants were subjected to a survey via a mobile application to obtain subjective measurements to calculate actual mean vote values. Based on objective and subjective measurements, the relationships among the parameters were derived by using simple regression analysis technique while a new combined mean vote correlation was also derived but this time by using multiple linear regression model. Neutral and comfort temperatures were obtained using indoor air temperature and actual mean vote values which were calculated from subjective measurements. The results showed that neutral temperature in the university office building was 20.9 degrees C whilst the comfort temperature range was between 19.4 and 22.4 degrees C for the heating season. By applying new comfort temperatures, energy consumption of the case building located in Mediterranean climate, can be reduced.