Energy Systems Engineering / Enerji Sistemleri Mühendisliği
Permanent URI for this collectionhttps://hdl.handle.net/11147/4752
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Article Citation - WoS: 5Citation - Scopus: 5Exergetic Assessment of an Solar Powered Stand-Alone System Using Liquid Organic Hydrogen Carrier for Energy Storage(Elsevier, 2023) Palmero-Marrero, Ana I.; Zairov, Rüstem; Borge-Diez, David; Çağlar, Başar; Açıkkalp, Emin; Altuntaş, ÖnderThe integration of energy storage technologies into renewable energy systems has gained increasing attention for continuous supply of the renewable-based enegy. Among different storage alternatives, the use of a Liquid Organic Hydrogen Carrier (LOHC) has a significant potential as a reversible energy carrier for short and longterm energy storage. In this study, the technical and economic performance of an stand-alone renewable energy systems using a LOHC for energy storage have been evaluated by exergy-based methods in addition to simple energy and economic analysis. The analysis of the LOHC-free system was also included to determine the effect of LOHC on the system performance. The system containing phovoltaic (PV) panels, an electrolyzer, a micro gas turbine and hydrogenation/dehydrogenation LOHC units was designed to meet the power, heating and cooling requirement of a residential building. The system modelling and performance evaluation were made by using TRNSYS and EES softwares. Results show that the LOHC-containing system has higher energy and exergy efficiencies and exergoeconomic performance than the LOHC-free system while the latter is economically more feasible than the former due to its low capital investment cost.Review Citation - WoS: 21Citation - Scopus: 23A Comprehensive Review of Computational Fluid Dynamics Simulation Studies in Phase Change Materials: Applications, Materials, and Geometries(Springer, 2023) Soodmand, A. Mohammadian; Azimi, B.; Nejatbakhsh, S.; Pourpasha, H.; Farshchi, M. Ebrahimi; Aghdasinia, H.; Mohammadpourfard, Mousa; Heris, S. ZeinaliThermal energy storage systems (TESS) have emerged as significant global concerns in the design and optimization of devices and processes aimed at maximizing energy utilization, minimizing energy loss, and reducing dependence on fossil fuel energy for both environmental and economic reasons. Phase change materials (PCMs) are widely recognized as promising candidates due to their high latent heat storage (LHS) capacity. This review thoroughly evaluates the computational fluid dynamics (CFD) studies conducted in various sections, encompassing materials, modeling, simulation, as well as the results, advantages, and disadvantages of these works. The study is organized into three distinct sections. The first section discusses the applications of PCMs in various areas, including lithium-ion batteries, solar applications, building applications, electronics, and heating and cooling systems. The second section provides a comprehensive summary of cylindrical, rectangular, spherical, arbitrary shapes, and packed-bed geometries employed in TESS. The third section investigates the different types of materials used as PCMs. Based on the findings of this study, it can be concluded that industrial applications of hybrid nanocomposites incorporating PCMs in different geometries pose challenges, particularly in three-dimensional (3D) settings, where instability becomes a significant concern. Hence, further research and investigation are necessary to address these challenges adequately. In conclusion, this study serves as a reference review for future research endeavors in the field of simulating various PCMs in different geometries and applications. It provides valuable insights into the current state of knowledge, highlights potential areas for improvement, and offers guidance for advancing simulation techniques related to PCMs.Article Citation - WoS: 30Citation - Scopus: 30A 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, GüldenThermal 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: 103Citation - Scopus: 113Preparation and Characterizations of Tio2/Zno Nanohybrid and Its Application in Photocatalytic Degradation of Tetracycline in Wastewater(Elsevier, 2023) Zeinali Heris, Saeed; Etemadi, Martin; Mousavi, Seyed Borhan; Mohammadpourfard, Mousa; Ramavandi, BahmanThe photodegradation of tetracycline antibiotics (TC) in an aqueous solution, using the TiO2 nanoparticles, ZnO microparticles, and TiO2/ZnO composite under the UV lamp in a continuous reactor, was performed. The effects of different parameters, such as the initial TC concentration, medium pH, ratio of each photocatalyst, and the flow rate were comprehensively studied. SEM, EDX, and XRD characterization techniques were employed to study the morphology and structure features of the prepared composite. The results revealed that a more significant amount of TC is not easily removed from wastewater. Furthermore, by increasing the pH of the medium to 11, the efficiency of TC degradation was increased, while the amount of removal remained stable at higher pH values. As the flow rate increased up to 190 mL/min, the removal efficiency increased; however, at higher flow rates, lower efficiency was obtained. Moreover, using multivariate analysis and response surface methodology (RSM), a model for removing TC and the effect of experimental parameters on removal efficiency was proposed. The optimal conditions using the RSM method were found to be the reduction efficiency of 78.94 % in pH = 11 (flow rate of 132 mL/min, and TiO2 concentration of 323 mg) and reduction efficiency of 75.89% in pH = 9 (flow rate of 143.19 mL/min and TiO2 concentration of 312.73 mg). © 2023 Elsevier B.V.Article Citation - WoS: 15Citation - Scopus: 18An 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, GüldenUrban 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: 7Citation - Scopus: 7Comprehensive Thermoeconomic Study of a New Solar Thermosyphon-Assisted Multigeneration System(Elsevier, 2023) Anamaq, Rasoul Najafi; Khani, Leyla; Mohammadpourfard, Mousa; Heris, Saeed Zeinali; Gökçen Akkurt, GüldenNowadays, due to the global energy crisis, limited reservoirs of fossil fuels, and their negative environmental effects, the use of renewable energy sources and multigeneration systems have become good alternatives for conventional thermodynamic systems. One of these resources, whose technology has developed rapidly in recent years, is the use of solar energy for the simultaneous generation of various products. Therefore, in this research, a multigeneration system with several subsystems is introduced. The proposed system includes a solar energy collector to receive thermal energy, two thermal energy storage tanks, an organic Rankine cycle, and a Kalina cycle to generate electricity, a multi-effect distillation unit to produce fresh water, an electrolyzer to produce hydrogen, as well as heat recovery for hot water and hot air generation. In this multigeneration system, the cooling unit is designed with the help of a thermosyphon. The performance of the proposed system is studied from energy, exergy, environmental, and exergoeconomic viewpoints using Aspen HYSYS and EES software. The obtained results show that due to the addition of the thermosyphon unit to the refrigeration system, the exergy efficiency increases from 55.62% to 70.26%. As a result of this combination, the performance of the whole system is improved and the amount of costs are reduced. In addition, the parabolic collector system has the highest exergy destruction ratio, 39%, among the subsystems. Furthermore, the results of the exergoeconomic analysis indicate that the PEM water heater with 33.3% and the ejector with 22.7% own the highest cost destruction rates.Article Citation - WoS: 45Citation - Scopus: 31Highly Efficient Treatment of Petrochemical Spent Caustic Effluent Via Electro-Fenton Process for Cod and Toc Removal: Optimization and Experimental(Springer, 2023) Gholami, Asma; Mousavi, Seyed Borhan; Heris, Saeed Zeinali; Mohammadpourfard, MousaCaustic is commonly used in oil and gas refineries to remove CO2, H2S, organic sulfur, and acidic compounds; however, spent caustic must be treated considering the type of wastewater in refinery and petrochemical units due to their hazardous characteristics. This research aims to reduce the chemical oxygen demand (COD) and the total organic carbon (TOC) from the used caustic effluent of the olefin unit of Ilam Petrochemical Company employing the electro-Fenton method. The affecting parameters, such as H2O2 concentration, reaction time, pH, and current density on the COD and TOC removal rate, were investigated. An experimental design by response surface methodology (RSM) based on the Box–Behnken method with the considered factors was considered to study the setup’s effectiveness and optimize the conditions. The outcomes revealed that by increasing the H2O2 concentration from 11 to 18 mgL, the COD removal efficiency was enhanced from 68 to 93%. On the other hand, by increasing the reaction time after 15 min, the COD and TOC removal efficiency decreased. The same trend was observed by increasing the current density after the optimal value. The optimal conditions were acquired at pH = 4, current density = 20 mAcm2, H2O2 concentration = 18 mgL, and reaction time = 15 min. The promising results confirmed that the electro-Fenton could be an excellent treatment technique in Ilam Petrochemical Unit as a spent caustic treatment. © 2023, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.Article Citation - WoS: 8Citation - Scopus: 10Spray Analysis of Biodiesels Derived From Various Biomass Resources in a Constant Volume Spray Chamber(American Chemical Society, 2022) Ulu, Anılcan; Yıldız, Güray; Rodriguez, Alvaro Diez; Özkol, ÜnverThis research aimed to analyze the spray characteristics of various biodiesels, which have rarely been investigated in terms of spray analysis in the literature compared to fossil diesel. For this purpose, four different methyl ester-type biodiesels were produced from canola, corn, cottonseed, and sunflower oils. These feedstocks were selected due to their wide availability in Turkey and being among the significant resources for biodiesel production. Measured physical properties of biodiesel samples showed that biodiesel fuels had, on average, 1.7 to 1.9 times higher viscosities, 5.3 to 6.6% larger densities, and 37 to 39.1% higher contact angle values than the reference diesel fuel. Spray characteristics of all fuels were experimentally examined in a constant volume spray chamber under chamber pressures of 0, 5, 10, and 15 bar and injection pressures of 600, 800, and 1000 bar. All tested biodiesels performed, on average, 3 to 20% longer spray penetration lengths, 5 to 30% narrower spray cone angles, and 5-18% lesser spray areas than the reference diesel fuel under chamber pressures of 5 and 10 bar. No significant differences occurred at 15 bar ambient pressure between biodiesels and diesel. In addition, analytical and empirical predictions showed that biodiesels had around 21.2-35.1% larger SMD values and approximately 7% lower air entrainment.Article Citation - WoS: 9Citation - Scopus: 11Experimental Investigation of Spray Characteristics of Ethyl Esters in a Constant Volume Chamber(Springer, 2022) Ulu, Anılcan; Yıldız, Güray; Özkol, Ünver; Rodriguez, Alvaro DiezAbstract: Biodiesels are mainly produced via the utilization of methanol in transesterification, which is the widespread biodiesel production process. The majority of this methanol is currently obtained from fossil resources, i.e. coal and natural gas. However, in contrast with methanol, biomass-based ethanol can also be used to produce biodiesels; this could allow the production line to become fully renewable. This study aimed to investigate the spray characteristics of various ethyl ester type biodiesels derived from sunflower and corn oils in comparison to methyl esters based on the same feedstocks and reference petroleum-based diesel. Spray penetration length (SPL) and spray cone angle (SCA) were experimentally evaluated in a constant volume chamber allowing optical access, under chamber pressures of 0, 5, 10 and 15 bar and injection pressures of 600 and 800 bar. Sauter mean diameter (SMD) values were estimated by using an analytical correlation. Consequently, ethyl esters performed longer SPL (2.8–20%) and narrower SCA (5.1–19%) than diesel under ambient pressures of 5 and 10 bar. Although the SMD values of ethyl esters were 48% higher than diesel on average, their macroscopic spray characteristics were very similar to those of diesel under 15 bar chamber pressure. Moreover, ethyl esters were found to be very similar to methyl esters in terms of spray characteristics. The differences in SPL, SCA and SMD values for both types of biodiesels were lower than 4%. When considering the uncertainty (± 0.84%) and repeatability (±5%) ratios, the difference between the spray characteristics of methyl and ethyl esters was not major.Article Citation - WoS: 77Citation - Scopus: 95Sustainable Use of Apple Pomace (ap) in Different Industrial Sectors(MDPI, 2022) Gołębiewska, Ewelina; Kalinowska, Monika; Yıldız, GürayIn many countries, apple pomace (AP) is one of the most produced types of agri-food waste (globally, it is produced at a rate of ~4 million tons/year). If not managed properly, such bio-organic waste can cause serious pollution of the natural environment and public health hazards, mainly due to the risk of microbial contamination. This review shows that AP can be successfully reused in different industrial sectors—for example, as a source of energy and bio-materials—according to the idea of sustainable development. The recovered active compounds from AP can be applied as preservatives, antioxidants, anti-corrosion agents, wood protectors or biopolymers. Raw or processed forms of AP can also be considered as feedstocks for various bioenergy applications such as the production of intermediate bioenergy carriers (e.g., biogas and pyrolysis oil), and materials (e.g., biochar and activated carbon). In the future, AP and its active ingredients can be of great use due to their non-toxicity, biodegradability and biocompatibility. Given the increasing mass of produced AP, the commercial applications of AP could have a huge economic impact in the future.