Sürdürülebilir Kalkınma Amaçları
Yayınlar
- MakaleAçık Erişim2026Scopus SJRQ1Multi-parameter hydrodynamic analysis of pulsation frequency and waveform effects in a conical spouted bed: A CFD study
Çutay, Arif; Tozlu, Alperen; Kütük, Begüm; Özahi, Emrah
The hydrodynamic behavior of spouted beds is strongly influenced by inlet flow conditions, particularly under pulsating operation. In this study, a three-dimensional Eulerian–Eulerian two-fluid model coupled with the kinetic theory of granular flow was used to investigate the effects of pulsation frequency and waveform on the hydrodynamics of a conical spouted bed. Steady, sinusoidal, pulsatile, and square-wave inlet conditions were analyzed at 1, 3, 5, and 10 Hz. A multi-parameter evaluation framework was applied by combining spout height, temporal stability, axial gas and particle velocity distributions, and mixing characteristics. Spout height was determined using the connected αs=0.05 iso-contour, while temporal behavior was quantified through the mean spout height, standard deviation, coefficient of fluctuation, and fluctuation range. The results show that spout performance depends not only on instantaneous inlet velocity but also on the persistence of axial momentum transfer. Although the steady condition and some high-penetration pulsating cases produced relatively large instantaneous spout heights, they did not necessarily provide the most favorable hydrodynamic behavior because of rapid velocity decay, stronger fluctuations, or reduced structural coherence. Pulsation at 3 Hz provided the best overall balance by sustaining particle transport and improving temporal stability. The 5 Hz cases enhanced mixing but exhibited larger fluctuations, whereas the 10 Hz cases produced weaker and less coherent spout structures because of rapid attenuation of the imposed oscillations. Overall, the proposed framework demonstrates that spouting performance should be evaluated through the combined effects of penetration, stability, momentum persistence, and mixing.
AtıfOpenAlex1
İncele - MakaleAçık Erişim2026Scopus SJRQ1A comparative study of metaheuristic algorithms for thermoeconomic optimization of an Organic Rankine Cycle
Tayfur, Bilal; Turhal, Uğur; Tozlu, Alperen
The efficient recovery of waste heat from biogas power plants via Organic Rankine Cycles (ORC) is essential for sustainable energy but requires satisfying conflicting thermodynamic and economic objectives. This study addresses the need for robust optimization strategies by evaluating nine recent metaheuristic algorithms to identify the most effective methods for maximizing net power while minimizing system costs. A multi-objective thermoeconomic model utilizing the specific exergy costing method was developed for a toluene-based ORC and optimized using algorithms including Dung Beetle, Snake, and NSGA-II. The optimization reduced the unit electricity cost by 9.1% (from $0.088/kWh to $0.080/kWh), with the Dung Beetle algorithm exhibiting superior convergence (Hypervolume 25.90) and the Snake algorithm demonstrating the best solution uniformity (Spread 1.54) with computational speed (0.084 s). These findings underscore that selecting algorithms based on specific exploration-exploitation characteristics is critical for achieving cost-effective and thermodynamically efficient power generation designs.
AtıfOpenAlex2İncele - Derleme MakaleAçık Erişim2026Environmental and economic analysis of industrial waste heat recovery with hybrid heat pump application
Kazici, Halil İbrahim; Tozlu, Alperen
Today, increasing energy demands and environmental concerns have made energy efficiency a necessity from both economic and ecological perspectives. High energy consumption in industrial facilities increases costs and raises CO2 emissions. Therefore, waste heat recovery and the use of renewable energy are among the fundamental goals of sustainable production. Energy efficiency is important not only for reducing consumption but also for lowering greenhouse gas emissions, protecting the environment, and strengthening the economics of the business. In this context, heat pump technologies, which extract energy from low-temperature sources and make it reusable, stand out as effective, environmentally friendly, and efficient systems in both heating and cooling applications. In this study, waste heat from a cooling tower generated during the production process in an industrial facility was recovered through a water-source heat pump and integrated into the facility's heating system. The heat pump increased the heat energy by using low-temperature water and reused it in the process. During periods when the waste heat was insufficient, the system was supported by natural gas boilers, thus creating a hybrid operating model between the heat pump and the boiler. As a result of the implementation, natural gas consumption and electricity usage were significantly reduced, leading to lower energy costs and a substantial decrease in CO2 emissions, thereby providing notable environmental benefits. The findings indicate that the proposed system achieves an annual natural gas saving of 6,788,251 kWh and a net financial gain of 5,703,864 TL. Additionally, the payback period of the investment is calculated as 2.41 years, demonstrating the economic feasibility of the system. Overall, this case study highlights that the widespread adoption of hybrid heat pump systems in the industrial sector can make significant contributions to Türkiye’s energy transition and carbon emission goals.
- MakaleYalnız künye2026Scopus SJRQ2Hydrodynamic characterization and design evaluation of a conical spout–fluidized bed under geometric and gas-distribution effects
Çutay, Arif; Tozlu, Alperen; Özahi, Emrah
Spout–fluidized beds are widely used in gas–solid processing and thermal conversion applications because of their enhanced particle circulation, mixing, and heat-transfer characteristics. However, the combined effects of reactor geometry, distributor configuration, and gas-flow distribution on the hydrodynamic organization of conical spout–fluidized beds are still not sufficiently quantified from a design perspective. In this study, a three-dimensional transient numerical analysis was performed to assess the effects of cone angle, auxiliary-hole number, and auxiliary-to-total flow-rate ratio on gas–solid flow behavior in a conical spout–fluidized bed reactor. The simulations were carried out using an Eulerian–Eulerian two-fluid model coupled with the kinetic theory of granular flow and the Syamlal–O'Brien drag model. Three cone angles (50°, 60°, and 70°), three distributor configurations with 70, 140, and 210 auxiliary holes, and two auxiliary-to-total flow-rate ratios (Qf/QT≈0.15 and Qf/QT=0.43) were investigated. The hydrodynamic response was evaluated using particle velocity, voidage distribution, and two compact flow indices: the radial spout heterogeneity index (RSHI) and the axial spout regularity index (ASRI). The results show that the flow field is governed by a characteristic core–annulus structure consisting of a dilute, high-velocity spout core and a denser recirculating annulus. Increasing Qf/QT enhances auxiliary gas penetration, particle suspension, and radial expansion of the gas-penetrated region; however, it also increases RSHI and ASRI, particularly at lower cone angles, indicating stronger radial heterogeneity and axial irregularity. Increasing the cone angle from 50° to 70° reduces radial hydrodynamic heterogeneity and improves axial spout regularity, whereas the number of auxiliary holes has a secondary and configuration-dependent influence compared with the gas-flow distribution and cone angle. Overall, the findings indicate that the auxiliary-to-total flow-rate ratio primarily controls gas distribution and gas–solid momentum exchange, while the cone angle governs radial uniformity and axial spout regularity. The proposed RSHI–ASRI framework provides a design-oriented basis for comparing conical spout–fluidized bed configurations and selecting operating conditions according to the desired balance between gas–solid interaction intensity, radial uniformity, and axial spout regularity.
- MakaleAçık Erişim2025Scopus SJRQ1Energy, exergy and economic optimization application of integrated dual-loop organic rankine cycle: A case of shopping mall power plant
Topcu, Muhammed Taha; Tozlu, Alperen; Bilen, Kadir
This paper presents a thermoeconomic analysis of the Dual-Loop Organic Rankine Cycle (DORC) integrated into the Erzurum Mall Power Plant (EMPP). The DORC system is designed to utilize waste heat at 425 degrees C and 9 kg/s, producing additional power for the existing plant. The integration of dual-loop ORC systems with different critical temperature fluids into an operational facility is analyzed. High-temperature cycles use working fluids such as Toluene, MDM (octamethylcyclotrisiloxane), n-Nonane, and n-Octane, while refrigerants R236fa, R600a, and R124 are employed in the low-temperature cycles. The designed model demonstrates that up to 11.4 % of the plant's existing capacity can be added as extra power. The Toluene/R600a combination is identified as the best fluid pair, delivering the highest total net power output (653.4 kW), the lowest total cost rate (19.18 $/h), and the highest exergy efficiency (20.18 %). Optimization of the DORC system is performed using the NSGA-II in MATLAB. For the toluene/R600a pair, the optimization results show an increase of 13.52 % in the net power output and decrease of 1.48 % in the total cost rate, which is a significant improvement over the initial results.
AtıfWoS3OpenAlex1İncele - MakaleAçık Erişim2024Scopus SJRQ1District heating based on exhaust gas produced from end-of-life tires in Erzincan: Thermoeconomic analysis and optimization
Güngör, Osman; Tozlu, Alperen; Arslantürk, Cihat; Özahi, Emrah
This paper presents the thermoeconomic analysis and optimization of the Erzincan Waste Tire Recycling and Power Plant (EWTRPP) in Turkey and its waste heat-based district heating (DH) system. A thermoeconomical method, namely the specific exergy costing (SPECO), is applied to allocate cost flows through subcomponents of an actual existing plant. Besides, the obtained thermoeconomic results are improved by using an optimization method, namely non-dominant sorting genetic algorithm (NSGA-II), considering the temperature of the exhaust gas discharged to the atmosphere (T25), the thermal conductivity value of the insulation material (ki) and pipe roughness value (s). The energy and exergy efficiencies of the existing plant are found to be 27.37% and 35.57%, respectively, considering the data of the actual plant. Moreover, the energy and exergy efficiencies of the waste heat-based DH system are found to be 43.08% and 55.99%, respectively. The total cost rate of the overall system is deduced 13.98 $/hby means of SPECO method. According to the results of the NSGA-II optimization method, the exergy efficiency and total cost rate of the overall system are evaluated as 6.93% and −2.51 $/h, respectively. Furthermore, it is also proposed that 1304 dwellings can be heated owing to the DH system utilizing the existing exhaust gas.
AtıfScopus9WoS8OpenAlex7İncele - MakaleAçık Erişim2022Scopus SJRQ1Techno-economic assessment of a synthetic fuel production facility by hydrogenation of CO2 captured from biogas
Tozlu, Alperen
In this study, a thermodynamic and economic analysis of a synthetic fuel production facility by utilizing the hydrogenation of CO2 captured from biogas is carried out. It is aimed to produce methanol, a synthetic fuel by hydrogenation of carbon dioxide. A PEM electrolyzer driven by grid-tie solar PV modules is used to supply the hydrogen need of methanol. The CO2 is captured from biogas produced in an actual wastewater treatment plant by a water washing unit which is a method of biogas purification. The required power which is generated by PV panels, in order to produce methanol, is found to be 2923 kW. Herein, the electricity consumption of 2875 kW, which is the main part of the total electricity generation, belongs to the PEM system. As a result of the study, the daily methanol production is found to be as 1674 kg. The electricity, hydrogen and methanol production costs are found to be $ 0.043 kWh−1, $ 3.156 kg−1, and $ 0.693 kg−1, respectively. Solar availability, methanol yield from the reactor, and PEM overpotentials are significant factors effecting the product cost. The results of the study presents feasible methanol production costs with reasonable investment requirements. Moreover, the efficiency of the cogeneration plant could be increased via enriching the biogas while emissions are reduced.
AtıfScopus34WoS32OpenAlex37İncele - MakaleAçık Erişim2022Scopus SJRQ2Assessment of waste-to-energy potential of ELT management: An actual case study for Erzincan
Güngör, Osman; Tozlu, Alperen; Arslantürk, Cihat
End-of-life tires (ELTs) and their decomposition are becoming a major environmental issue in the local region as a result of economic and technological challenges. Despite this, ELT management is gaining popularity as an advanced function for treating tires to obtain char, oil, and gas products using pyrolysis. The main goal of this article is to integrate data from an actual recycling plant with the activities of pyrolysis products and their physical properties in the literature. This article presents energy potentials and basic applications of pyrolysis products as well as advances in the current situation in ELT management in the world. Accordingly, an existing ELT management in Erzincan, Turkey is explained in detail by considering the available energy recovery and material treatment activities. In this plant, which has an installed power capacity of 12 MW, approximately 25 tons of pyrolytic oil, 10.7 tons of pyrolytic gas, 24 tons of carbon black and, 10.4 tons of steel are produced daily. The calorific values of carbon black and pyrolytic oil for the products leaving the pyrolysis plant are close to the values in the literature, which is promising. In the plant, the overall thermal efficiency of the system and the engine is found to be 26.34% and 51.24%, respectively. On the other hand, to supply additional power to the plant utilizing exhaust gas discharged to the atmosphere, some thermodynamic models can be developed; additionally, more rational values can be obtained through thermoeconomic and optimization.
AtıfScopus1WoS2OpenAlex3İncele - MakaleAçık Erişim2022Scopus SJRQ1Thermoeconomic analysis of a low-temperature waste-energy assisted power and hydrogen plant at off-NG grid region
Tozlu, Alperen; Kayabasi, Erhan; Ozcan, Hasan
In this study, thermoeconomic analysis of a CO2 power cycle and PEM hydrogen system using ultra-low temperature waste heat from a milk production facility is conducted. In the transcritical CO2 cycle, low-temperature LNG evaporation is used for cooling the condenser to increase the temperature difference enabling low temperature waste heat use. In addition, a PEM electrolyzer produces hydrogen to reduce the LNG requirement at the plant. A CO2-water exchanger has been designed to recover the pasteurized water's excess heat and evaporate the CO2 using Simcenter-Flomaster software. The inlet mass flow rates and outlet temperatures of the heat exchanger were optimized by performing thermoecomic analysis, and the thermal and economic performance of the facility was examined. The power cycle has 14% higher efficiency when LNG is used as the heat sink compared to ambient temperature condensation with an electricity production cost range at 0.05–0.11 $/kWh, and the hydrogen generation cost is between $2.6–5.20 kg−1. It is found that the plant could only be economically feasible when less than 50% of the power produced is used for hydrogen generation. Consequently, the proposed system can co-generate power and on-demand hydrogen in off-NG grid regions with reasonable investment and product costs.
AtıfScopus6WoS6OpenAlex8İncele - Derleme MakaleAçık Erişim2021Investigation of Shale Gas Reserves in The World and A Case Study for Electricity Production from Shale Gas in Turkey
Oztekin, Erman Kadir; Tozlu, Alperen
Shale gas reserves, which is globally accepted as unconventional gas resource, scattered around the world and can be used in order to meet the growing energy needs due to limited amounts of conventional resources. Since notable effort has to be put in order to investigate and drill shale gas resources the early decision has to be made carefully, especially considering the economic benefits. Several factors must be considered including the known technically recoverable shale gas amount at the selected region, current technology to drill the shale source and the amount of investment before the extraction of shale gas. In this study, global underground shale gas amount and recent discoveries as well as the potential shale gas areas in Turkey are presented. Benefits of using shale gas for electricity generation and common methods being used during shale gas extraction are studied along with gas and liquid flow mechanisms. At the end, general overview of separation and utilization of shale gas components is schematically presented. In the case study, the potential of electricity generation in the SE Anatolia region in Turkey is estimated with only using methane obtained from the shale gas purification process at the power generation step. According to the estimations, 3337.8 MW electric power may be generated for 50~55 years, at the appropriate gas engine by using 8.5 billion cubic meter shale gas annually.
- MakaleAçık Erişim2021Scopus SJRQ1District heating and electricity production based on biogas produced from municipal WWTPs in Turkey: A comprehensive case study
Abusoglu, Aysegul; Tozlu, Alperen; Anvari-Moghaddam, Amjad
In this paper, district heating (DH) potentials of the wastewater treatment plants (WWTPs) based on their biogas, electricity, and heat productions are considered. Two district heating scenarios are developed: (i) DH Scenario I which is based on both excess biogas storage of the WWTP and exhaust gas of the cogeneration with the actual power output, (ii) DH Scenario II which is based on the exhaust gas of the cogeneration with the increased power output using all the biogas produced. In DH Scenario I, it is found that 458 dwellings can be heated via the DH system proposed considering only the waste heat of the cogeneration. In addition, the natural gas consumption of 1112 dwellings with the same annual heating load can also be met using the purified biogas. In DH Scenario II, the electricity production could be increased to 1643 kWh by burning all the biogas produced in the cogeneration plant. In this scenario, the annual heating load of 755 dwellings in Gaziantep province can be covered using the waste heat in the DH system. The payback period for the DH Scenario I is calculated as 2.5 years, while for the DH Scenario II, it is obtained as 2 years.
AtıfScopus27WoS28İncele - MakaleYalnız künye2021Scopus SJRQ2Thermodynamic feasibility analysis of a newly modified absorption power cycle running with LiBr-water
Tozlu, Alperen; Yosaf, Salem A.; Özcan, Hasan
This study thermodynamically evaluates a newly modified absorption power cycle (APC) working with Lithium Bromide–Water (LiBr-H2O) solution and compares it with the conventional Rankine, one-stage, and three-stage APC systems. An additional steam condenser is integrated to the conventional APC and part of pure water is extracted and pumped back to the high-pressure side without passing through the absorber of the cycle. In order to specify the best system parameters, parametric optimization of all configurations is evaluated. The Rankine cycle and the modified APC have better thermodynamic performances than those of the conventional and the three-stage APC at generator temperatures. The conventional APC is found to improve the cycle performance at low generator pressure. However, the efficiencies of this cycle start to decrease when generator pressure increases. In contrast, the Rankine cycle and the modified APC have larger working ranges of generator pressure.
AtıfScopus8WoS5OpenAlex7İncele - MakaleAçık Erişim2021Scopus SJRQ1Municipal solid waste-based district heating and electricity production: A case study
Tozlu, Alperen; Abusoglu, Aysegul; Ozahi, Emrah; Anvari-Moghaddam, Amjad
In this paper, municipal solid waste (MSW) based electricity production and district heating (DH) potential of Turkey are considered. Three MSW based waste-to-energy (WtE) scenarios is developed: (i) Scenario-I, a DH system integrated into a gas turbine power plant (GTPP), (ii) Scenario-II, a DH system integrated into an organic Rankine cycle (ORC), and (iii) Scenario-III, which is based solely on a DH system. As a result of the thermodynamic and thermoeconomic analyzes of these developed scenarios using an existing MSW-based cogeneration facility's actual operating data, the system with the most extended payback period (about 5 years) is found as the GTPP-DH system developed in Scenario-I, which also has the highest investment cost. On the other hand, the system with the shortest payback period (about 2 years) is found as the DH system developed in Scenario-III, which also has the lowest investment cost. Overall exergy efficiencies of the GTTP-DH, ORC-DH, and DH systems are found to be 41.86%, 16.15%, and 31.87%, respectively. When the developed WtE scenarios adapted to the pilot provinces selected from each geographical region of Turkey, it is found that the GTPP system developed in Scenario-I can increase the power generation capacity of MSW plants for each province by about 20%.
AtıfScopus16WoS15OpenAlex16İncele - MakaleAçık Erişim2021Scopus SJRQ1Thermoeconomic analysis of a hybrid cogeneration plant with use of near-surface geothermal sources in Turkey
Tozlu, Alperen; Gençaslan, Betül; Özcan, Hasan
In this study, thermodynamic and thermoeconomic analyses of systems that produce electricity and heat through the use and storage of solar energy and near-surface geothermal sources are carried out. Three different configurations, which are the organic Rankine cycle (ORC), cogeneration system (CGN) and hybrid system (HYB), are coupled to the parabolic trough collector (PTC) system. The systems are named PTC-ORC, PTC-CGN and PTC-HYB are conducted. The reference system called PTC-ORC only produces electrical energy with parabolic trough collectors and it does not have a thermal energy storage system, whereas in PTC-CGN, in addition to the cogeneration of electricity and heat, thermal energy storage is also available. Finally, thermodynamic and economic analyses are conducted in the PTC-HYB with the assistance of near-surface geothermal energy, which is widely available in Turkey. In this study, the actual data of Ankara Kızılcahamam near-surface geothermal fields are taken as the heat source for the hybrid system. These facilities, each producing 1 MW of electricity, are first optimized with the help of parametric studies, and exergoeconomic analysis is performed with respect to optimum thermal conditions. The electricity production costs of PTC-ORC, PTC-CGN and PTC-HYB are found to be 0.257 $/kWh, 0.448 $/kWh and 0.401 $/kWh, respectively. The study demonstrates that thermal energy storage brings extra costs, while near-surface geothermal sources may help decrease energy costs from renewables.
AtıfScopus15WoS13OpenAlex21İncele - MakaleAçık Erişim2021Scopus SJRQ1A comparative thermoeconomic analysis and optimization of two different combined cycles by utilizing waste heat source of an MSWPP
Ozahi, Emrah; Abusoglu, Aysegul; Tozlu, Alperen
In this paper, thermodynamic and thermoeconomic analysis as well as genetic algorithm optimization of two combined cycles, a gas turbine-organic Rankine cycle (GT-ORC) and a gas turbine-Kalina cycle (GT-KAL) are carried out. The novelty of this study is that the cycles are adapted to an actual solid waste power plant to generate additional power from the exhaust gas. Thus, the power generation capacity of the actual power plant can be raised by using the combined cycle. Due to this reason, besides the thermodynamic analysis of the cycles, thermoeconomic analyses and optimizations are also very important in order to improve the actual system capacity. The net power output of GT-ORC and GT-KAL are found to be 1.51 MW and 1.59 MW, respectively. The results obtained are seen to be reasonable when compared to the net power output of the power plant (5.66 MW). Another originality of this study is that the thermoeconomic results are improved by utilizing a multi-objective optimization method namely non-dominated sorting genetic algorithm method (NSGA-II). Thus, the two objectives, total power output and the total cost rate, at the design stage of the cycles are optimized and enhanced. Due to the optimization results, it is found that the net power output of the GT-ORC and GT-KAL are increased by 11.34% and 0.99%, respectively, while the total cost rates are decreased by 18.59% and 1.31%, respectively. GT-ORC with the net power output of 1.70 MW is seen to be more efficient as compared to GT-KAL which produces a net power output of 1.61 MW. However, the total and the capital cost rates of GT-ORC are found to be higher than those of GT-KAL.
AtıfScopus7WoS5OpenAlex11İncele - Kitap BölümüAçık Erişim2020Scopus SJRQ4An updated portrait of numerical analyses on spout-fluidized bed incineration systems
Özahi, Emrah; Çutay, Arif; Abuşoğlu, Ayşegül; Tozlu, Alperen; Ivanov, V; Trojanowska, J; Machado, J; Liaposhchenko, O; Zajac, J; Pavlenko, I
Biodegradable wastes are becoming a serious problem in terms of health and ecological balance in parallel with the increasing of local and global populations in recent years. These wastes should be disposed in both efficient and eco-friendly ways. Considering biodegradable wastes as an energy source, it is necessary to be sure that those disposal methods should be focused on energy recovery. However, the existing waste disposal methods have not reached technologically targeted lines yet. It is very important that waste-to-energy recovery systems should have high energy conversion efficiency. Nowadays, there are many current studies based on the methods of wastes incineration. One of the most significant among these systems is fluidized or spout-fluidized bed incineration system. Unfortunately, the targeted points of the technological development of these systems in view of efficient energy recovery have not been reached yet. Existing incineration systems and current studies on this issue are generally concentrated on conventional fluidized bed systems. However, there are few studies of new generation spout-fluidized bed incineration systems which increase homogeneity and prevent waste from adhering to inner wall of a combustor. This study is focused on the conducted numerical studies in this research field. The latest developments and researches on both fluidized and spout-fluidized bed incineration systems will be investigated and discussed. The remarkable results will be pointed out by using the comparison in order to identify the gaps of the scientific literature.
- MakaleYalnız künye2020Scopus SJRQ1Optimization of an adapted Kalina cycle to an actual municipal solid waste power plant by using NSGA-II method
Özahi, Emrah; Tozlu, Alperen
In this paper thermodynamic and thermoeconomic analyses and even optimization of a Kalina cycle (KC) which is adapted to an actual solid waste power plant with a 5.66 MW installed capacity are presented as an alternative solution which is utilized to produce additional power from the exhaust gas of the plant. Up to now there is almost no study related with an adapted KC to a typical municipal solid waste power plant, and also no study based on an optimization, thermodynamic and thermoeconomic analyses of such a system together. All these facts show the novelty of this study. Herein the waste heat with a temperature of 566 °C is utilized by the adapted KC. According to the analyses of the first and second law of thermodynamics on the system, it is deduced that the electricity of 954.6 kW can be produced with the exergy efficiency of 24.15%. Furthermore, this power production can be improved by using non-dominated sorting genetic algorithm method (NSGA-II) in MATLAB software program. According to the optimization study, the deviations of the net power output and the total cost rate are found to be +3.62% and −1.47 $/h, respectively for the cycle.
AtıfScopus45WoS36OpenAlex49İncele - MakaleAçık Erişim2019Tepsili Bir Kurutucuda Kırmızı ve Yeşil Elma Parçacıklarının Kurutma Performanslarının Karşılaştırılması
Tozlu, Alperen
Bu çalışmada, tepsili kurutucuda kurutulması için yeşil ve kırmızı elmalar kurutma malzemeleri olarak seçilmiştir. Kurutulacak katı gıdalar, deney sonuçlarını olumsuz yönde etkileyebilecek tüm kirletici maddelerden arındırılmak için damıtılmış su ile yıkanmış ve aynı boyutlarda kesilmiştir. Her bir elma parçasının uzunluğu, genişliği ve kalınlığı sırasıyla 65 mm, 37 mm ve 12 mm olarak ayarlanmıştır. Elma parçacıkları hassas terazilerle tartılarak 50 g, 100 g ve 200 g olarak gruplandırılmıştır. Daha sonra her deney seti için parçacıklar tepsili kurutucuya yerleştirilmiş, daha sonra, kurutma işlemi, kırmızı ve yeşil elma parçacıklarının (mp) farklı ağırlıklarında, kurutma hava hızında (U) ve kurutma sıcaklıklarında (Td) gerçekleştirilmiştir. Burada nem içeriği (MC), kurutma malzemelerinin kurutma performansını ifade etmek için önemli bir parametre olarak kabul edilmiştir. Ayrıca, enerji verimliliği ve normalleştirilmiş nem içeriği, kurutma sistemleri için önerilen ampirik denklem ile karşılaştırılmıştır. Deneysel çalışma 50 g ≤ mp ≤ 200 g, % 18 ≤ MC ≤ % 614.29, 0.03 ≤ MR ≤ 1, 59 o C ≤ Td ≤ 99 o C ve 0.992 m/s ≤ U ≤ 1.488 m/s aralığında gerçekleştirilmiştir. Bu çalışmanın sonucu, kırmızı elma parçacıklarının, yeşil elma parçacıklarına kıyasla fiziksel özellikleri nedeniyle aynı koşullarda daha iyi kurutma performansına sahip olmasıdır.
- MakaleAçık Erişim2018Scopus SJRQ1Thermodynamic and thermoeconomic analyses of an organic Rankine cycle adapted gas turbine cycle using S-CO2
Tozlu, Alperen; Özahi, Emrah; Abusoglu, Aysegul
In this study, a model of an organic Rankine cycle (ORC) adapted gas turbine cycle using supercritical CO2 (S-CO2) as working fluid is performed. Thermodynamic analyses of system are carried out using Aspen Plus and EES programs. As a result of the thermodynamic analyses, electricity production capacity, energy and exergy efficiencies of proposed system are evaluated as 1530.88 kW, 23.30 % and 59.60 %, respectively. For the thermoeconomic analysis of the system, specific exergy costing method, SPECO, is applied as widely used one among the second law based methods. Unit exergetic cost of electricity production for 1 kWh is found to be 7.28 cent and the total cost of electricity production for 1530.88 kWh is found to be 114.43 $. The annual return from the system of the ORC adapted gas turbine cycle using S-CO(2)which has total investment cost of 3,033,300 $ is evaluated as 741,146 $ taking into account the difference between the cost of electricity production and sale price of electricity. As a result of the thermoeconomic analysis, the payback period of system is found to be 4.09 years.
AtıfWoS7OpenAlex2TR Dizin3
İncele - MakaleAçık Erişim2018Scopus SJRQ1Thermoeconomic multi-objective optimization of an organic Rankine cycle (ORC) adapted to an existing solid waste power plant
Özahi, Emrah; Tozlu, Alperen; Abuşoğlu, Ayşegül
In this paper, thermodynamic and thermoeconomic analyses, and also optimization of an organic Rankine cycle (ORC) were performed. The system was adapted to an existing solid waste power plant with a 5.66 MW installed power capacity in order to produce additional power from the exhaust gas. The actual operating data of the plant were utilized during all stages of the analyses. The originality of this paper is based on the analysis of the possibility of the energy conversion of an exhaust gas with a temperature of 566 & #x000B0;C into the electricity by utilizing an ORC system in the concept of waste-to-energy. Four different working fluids: toluene, octamethyltrisiloxane (MDM), octamethyl cyclotetrasiloxane (D4) and n-decane were considered and analyzed for the current system. This is also another novelty of this study due to lack of such a study, in the open literature, that deals with an ORC utilized for a typical municipal solid waste power plant. According to the thermoeconomic analyses, toluene was found to be the optimum working fluid with the maximum power output of 584.6 kW and the exergy efficiency of 15.69%. The optimization of the cycle was performed by using the non-dominated sorting genetic algorithm method (NSGA-II) in MATLAB software environment. The optimization results were compared and the deviations of the net power output and the total cost rate were evaluated as & #x2212;5.89%, & #x2212;3.51 & #x00024;/h for toluene; 0.96%, & #x2212;3.60 & #x00024;/h for MDM; 8.45%, & #x2212;2.04 & #x00024;/h for D4 and 2.00%, & #x2212;5.54 & #x00024;/h for n-decane, respectively.
AtıfScopus87WoS80OpenAlex88İncele