Sürdürülebilir Kalkınma Amaçları

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Araştırmacılar(34)

• Ağar, Salih
• Akkurt, Nevzat
• Aksakal, Bünyamin
• Anik, Kerem
• Atalar, Aydın
• Aydoğdu, Burcu
• Ayikurt, P.
• Bahar, Ahmet Serhat
• Çelik, Ertuğrul
• Çetin, Burcu
• Dilek, İlhan
• Doğan, Akar
• Ergin, Ramazan
• Fırat, Erhan
• Fırat, Tülay
• Fidan, Cihad
• Gök, Mehmet
• Gülçimen, Fevzi
• Güler, Ömer
• Güler, Seval Hale
• Güneş, Çağdaş
• Işık, Erdem
• Izguden, Ilyas
• Kahraman, Gökhan
• Kandemir, Seckin
• Kısmet, Yılmaz
• Mahmat, Aybars
• Malkoç, Aziz
• Özdemir, Osman
• Sabanci, Eray
• Taşar, Fatih
• Taşgın, Yahya
• Tuğan, Volkan
• Wagner, Manfred H.

• MakaleYalnız künye2026/r/munzur/6107
  Investigation of flow design and deflector plate effect in air cooled battery pack at different discharge rates

  Tuğan, Volkan; Yardımcı, Uğurcan

  In this study, the effect of different flow designs and the use of deflector plates on the thermal performance of an air cooled battery pack was investigated using the CFD method. Model A, which has a conventional single inlet flow structures, was compared with Model B, which employs dual inlets and deflector plates. In both models, 24 cylindrical 18650 lithium-ion battery cells were used, and the inlet and outlet surface areas of the battery pack were designed to be equal. Analyses performed at 3C and 4C discharge rates showed that the dual inlet flow structure and deflector plates significantly improved the cooling efficiency of the battery pack. At a 3C discharge rate, the maximum battery temperature and maximum temperature difference obtained with Model B were 1.87 K and 1.08 K lower, respectively, compared to Model A. At a 4C discharge rate, this improvement became even more pronounced, with the maximum battery temperature reduced by 2.49 K and the maximum temperature difference decreased by 1.44 K. Examination of the temperature contours revealed that, in Model A, heat accumulation occurred particularly in the rear regions, whereas Model B achieved a more homogeneous temperature distribution.

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• MakaleAçık Erişim2026/r/munzur/6101
  Obtaining Natural Dye from Oak Tree and Examination of Dyeing Properties According to Different Methods

  Fırat, Tülay

  This study investigates the dyeing performance of a natural dye extracted from the branches and leaves of the oak tree (soredar) on muslin fabric. The plant materials were soaked in water for 24 h and subsequently boiled to obtain the dye extract. Dyeing experiments were conducted using conventional dyeing methods with and without mordanting. Copper sulphate, iron sulphate, and potassium dichromate were used as mordants to evaluate their influence on the dyeing behavior of the fabric. The color properties of the dyed samples were determined using spectrophotometric measurements based on the CIELab color system, and color strength (K/S) values were calculated using the Kubelka–Munk equation. In addition, the durability of the dyed fabrics was assessed through washing, rubbing, and light fastness tests according to relevant ISO standards. The results revealed that the type of mordant significantly affected both color strength and fastness performance. Among the tested mordants, copper sulphate produced the highest color strength, while iron sulphate also improved dye uptake compared with the non-mordanted sample. Overall, the findings demonstrate that oak-derived natural dye can be effectively applied to muslin fabric and that mordanting plays a crucial role in enhancing the color depth and durability of natural dyeing processes.

  İncele
• MakaleAçık Erişim2026/r/munzur/5955
  Innovative System Design and Numerical Investigation Based on Air Cooling and Baffle Utilization in the Thermal Management of Lithium Ion Batteries

  Tuğan, Volkan; Yardımcı, Uğurcan

  Effective management of temperature in battery packs, which are used in a wide range of applications from portable devices to electric vehicles, plays a critical role in terms of both efficiency and safety. In this study, a new air cooling thermal management system was designed to improve the thermal management of lithium ion battery packs and was comparatively examined with a conventional system. In the developed design, front and rear air inlets along with a top outlet were implemented, and baffles were added to achieve a more homogeneous distribution of airflow between the cells. The conventional system, on the other hand, was modeled based on the principle of front inlet and rear outlet without baffles. These two designs were compared through CFD analyses in terms of maximum battery temperature and maximum temperature difference. In the analyses, three different inlet air temperatures of 299.15 K, 294.15 K, and 289.15 K were investigated. The airflow velocity at the entrance of the battery pack was set to 0.5 m/s. The analysis results showed that the developed design reduced the maximum battery temperature and maximum temperature difference by 1.82-3.38 K and 2.48-4.29 K, respectively, compared to the conventional design.

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  İncele
• MakaleYalnız künye2026Scopus SJRQ2/r/munzur/1377
  Adsorption of Reactive Red 120 dye from aqueous solutions using sepiolite clay with a channel-structured morphology: Mechanism, kinetics, isotherm, and thermodynamic studies

  Fırat, Tülay

  The effective treatment of dye-containing wastewater remains a major environmental challenge due to the high stability and solubility of reactive dyes. In this study, the adsorption behavior of Reactive Red 120 (RR120), an anionic reactive azo dye, from aqueous solutions was investigated using natural sepiolite clay possessing a channel-structured morphology. Batch adsorption experiments were performed to evaluate the effects of contact time (1–200 min), initial dye concentration (50–500 mg L−1), adsorbent dosage (0.1–1.5 g), solution pH (2–10), and temperature (25–50°C). The adsorption equilibrium was reached within approximately 75 min. The Langmuir isotherm provided the best fit to the equilibrium data, yielding a maximum monolayer adsorption capacity of 168.4 mg g−1 at 298 K. Thermodynamic analysis revealed that the adsorption process was spontaneous and endothermic, with an activation energy of 32.41 kJ mol−1. Adsorption kinetics were analyzed using pseudo-first-order, pseudo-second-order, and intraparticle diffusion models, while equilibrium data were evaluated using Langmuir, Freundlich, and Temkin isotherm models. The kinetic data were best described by the pseudo-second-order model, while thermodynamic analysis revealed that the adsorption process was spontaneous and endothermic. FTIR and XRD analyses further supported the important role of the channel-structured framework of sepiolite in RR120 adsorption. Unlike many clay-based adsorbents that require chemical modification, natural sepiolite exhibited high adsorption performance due to its intrinsic fibrous morphology, nano-channel structure, and high surface area. These findings demonstrate that natural sepiolite is a promising, low-cost, and sustainable adsorbent for the treatment of dye-contaminated wastewater.

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• MakaleYalnız künye2026Scopus SJRQ2/r/munzur/1365
  Influence of infill design on mechanical behavior of PLA-TPU hybrid sandwich beams

  Arikan, Volkan; Dogan, Akar; Guler, Serkan

  The purpose of this work is to analyze the mechanical behavior of hybrid sandwich beams that were printed using the Fused Deposition Modelling (FDM) technology. These beams were made of Polylactic Acid (PLA) and Thermoplastic Polyurethane (TPU) materials. Standard mechanical tests (ASTM C393 and C365) were utilized in order to assess the impact that several infill patterns (Cubic, Octet, and Trihexagonal) and infill densities (ranging from 15% to 40%) had on the flexural and compression performance of the material. According to the findings, trihexagonal patterns demonstrated improved energy absorption capabilities when subjected to compression, but octet designs offered superior flexural stiffness, particularly in hybrid constructions. According to the findings of tests conducted with hybrid constructions consisting of a TPU core and a PLA surface layer, the effect of infill patterns on component strength is directly influenced by the change in the material character, and it is possible that various materials would exhibit different manifestations of this effect. These findings offer useful information that may be used to optimize lattice geometry and hybridization procedures for the purpose of developing high-performance lightweight structures for engineering applications.

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  AtıfWoS1·OpenAlex2

  İncele
• MakaleAçık Erişim2026Scopus SJRQ1/r/munzur/1361
  Comparative effects of La2O3 and Sm2O3 on structural and radiation shielding properties of WO3 enriched borate glassy-ceramics

  Taşgın, Yahya; Yılmaz, Demet; Kanca, M. Sait; Yayla, Nihal; Kök, Mediha; Güler, Ömer

  This research comprehensively investigates the impact of incorporating rare earth oxides ‑samarium oxide (Sm2O3) and lanthanum oxide (La2O3)- into a borate glassy-ceramic system enriched with tungsten oxide (WO3), with a focus on both structural characteristics and radiation shielding performance. SEM-EDS, elemental mapping, and XRD analyses conducted on the synthesized glassy-ceramic samples revealed that the incorporated rare earth oxides, Sm2O3 and La2O3, were uniformly distributed throughout the glassy-ceramic matrix. The results also confirmed that the glassy-ceramic retained its inherently amorphous structure. Moreover, the nominal doping levels of the rare earth elements were found to be in agreement with both the qualitative and quantitative results obtained from EDS measurements. Also, the gamma ray shielding parameters of synthesized glassy-ceramic samples were measured in absorption geometry with Am-241, Ba-133 and Ra-226 radioactive sources. The neutron shielding parameters were theoretically calculated. The 241Am-Be fast neutron source was used to measure the equivalent dose of neutron absorption. At an incident photon energy of 74.8 keV, the mass attenuation coefficient of the tungsten oxide–enriched borate glassy-ceramic exhibited a remarkable improvement—rising by 17.98 % with the addition of 3 wt% Sm2O3 and by 11.58 % with the addition of 3 wt% La2O3. Notably, the N4 sample demonstrated a significant reduction in neutron-equivalent dose rate, reaching 19.80 % (μSv/h). The lead equivalent thicknesses (Pbeq) calculated at 356 keV were 0.02397 cmPb for N0, 0.0391 cmPb for N1, 0.0403 cmPb for N4, and 0.0389 cmPb for N7. When benchmarked against the undoped N0 sample, the N4 and N7 compositions exhibited reductions in Pbeq values by approximately 68 % and 62 %, respectively, indicating a marked improvement in gamma shielding efficiency. Among all tested formulations, the Sm2O3-doped variant demonstrated superior gamma-ray attenuation capability relative to the La2O3-doped glassy-ceramic. Furthermore, the N4 sample achieved an impressive thermal neutron attenuation rate of 96.46 %, underscoring its strong potential as an effective dual-purpose shielding material against both thermal neutrons and ionizing gamma radiation.

  AtıfScopus1

  İncele
• MakaleAçık Erişim2026Scopus SJRQ3/r/munzur/1326
  CFD Simulation of Aerodynamic Forces on a Simplified Heavy Vehicle Model with Steady Base Blowing

  Firat, Erhan; Seydhan, Mehmet

  A numerical investigation was conducted to examine the flow around a European tractor-trailer combination model (GETS) using a steady RANS model k-ω SST at a Reynolds number of 100000. Experimental aerodynamic force measurements were also carried out for the purpose of validating the CFD simulations. The present paper focuses on the effect of steady blowing from the thin slots positioned on the rear surface (base) of the model on the aerodynamic characteristics of the GETS. The combination of three key parameters was tested: the jet-to-freestream velocity ratio (VR), the inclination angle of the jet (θ), and the jet’s location. More than 100 CFD simulations were performed over a range of key parameters. The findings indicate that the jet direction’s inclination towards the rear surface typically leads to a modest yet favorable effect on the drag reduction. It has been demonstrated that increasing the VR to 2 has the potential to reduce aerodynamic drag by up to 50%. However, it is also demonstrated that employing VR values greater than approximately 1.25 is not viable in terms of active flow control efficiency. At θ=0°, the active control efficiency of the both-jets configuration is approximately 6 for VR=0.5 and approximately 1.6 for VR=1. The total drag coefficient on the model is reduced by 8.3% and 17.7% for the VR=0.5 and 1 cases, respectively. It has been demonstrated that the viscous components of total drag and lift are independent of jet configuration, VR, and θ. In both upper and lower jet configurations, it is possible to increase or decrease the aerodynamic lift acting on the model by changing the inclination angle.

  İncele
• MakaleYalnız künye2026Scopus SJRQ2/r/munzur/1303
  An Innovative Thermal Management Approach Enhanced by Thermoelectric Stations and Turbulators for Lithium-Ion Batteries

  Tuğan, Volkan; Yardımcı, Uğurcan

  The design of an effective battery thermal management system is critical to ensure the safe, efficient, and long-lasting operation of lithium-ion batteries. Excessive heat generation and temperature non-uniformity among cells in high energy density battery systems lead to performance degradation, accelerated aging, and an increased risk of thermal runaway. Although liquid-cooled systems and thermoelectric module-assisted solutions have been extensively investigated separately in the literature, studies that holistically evaluate multiple thermoelectric stations combined with an innovative flow channel design and turbulator integration remain limited. This gap constitutes a significant research need, particularly in terms of improving temperature uniformity and reducing maximum cell temperature. In this study, to address this research gap, a novel liquid-cooled battery thermal management system integrating thermoelectric coolers and turbulators within the flow channel is proposed. The thermal performance of the proposed system was systematically analyzed using computational fluid dynamics under three different configurations (conventional system, thermoelectric-assisted system, and turbulator-integrated thermoelectric-assisted system) and four different mass flow rates (0.0008, 0.0013, 0.0018, and 0.0023 kg/s). The results indicate that, at a mass flow rate of 0.0023 kg/s, the integration of thermoelectric coolers and turbulators reduces the maximum battery temperature by 8.95 K and the maximum temperature difference by 6.83 K. At the highest mass flow rate, the proposed system achieves a maximum battery temperature of 306 K and a maximum temperature difference of 4.5 K, ensuring both effective cooling performance and high temperature uniformity. Overall, the results in terms of cooling performance and temperature uniformity demonstrate that the combination of thermoelectric modules and turbulators offers significant potential for advanced battery thermal management system applications and offers an effective solution for high-energy-density systems.

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• MakaleAçık Erişim2026Scopus SJRQ2/r/munzur/1247
  Examination of the thermal and metallographic characteristics at high temperatures of natural stones (andesite) extracted from different elevations

  Işık, Erdem; Kahraman, Gökhan; Atalar, Aydın

  This study examines the high‑temperature thermal response of andesite stones extracted from two different elevations of Mount Ağrı (Türkiye) in order to improve material selection strategies for engineering applications. Thermal conductivity and density values of the samples were first measured under laboratory conditions. The specimens were then heated to 850 °C and cooled by natural convection while surface temperatures were recorded at fixed time intervals using a thermal camera. Based on these measurements, convective heat transfer coefficients were determined, and the time‑dependent thermal diffusivity and Biot numbers were subsequently calculated using the first-term approximation of the Fourier series. Metallographic examinations were conducted to correlate the thermal behavior with microstructural characteristics. Results indicate a pronounced effect of elevation on thermal performance. The sample obtained from the higher elevation exhibited substantially greater thermal diffusivity, reaching 2.93 × 10⁻5 m2 s−1 at 360 s and decreasing to 8.96 × 10⁻6 m2 s−1 at 1300 s. In contrast, the lower‑elevation andesite showed lower diffusivity values (1.83 × 10⁻5 m2 s−1 at 360 s and 5.9 × 10⁻6 m2 s−1 at 1300 s). Conversely, Biot numbers were consistently higher for the lower‑elevation sample, decreasing from 0.60 to 0.29 during the cooling process, whereas the high‑elevation sample displayed values from 0.314 to 0.165. Metallographic analysis confirmed that variations in microstructure—linked to different geological formation conditions—directly influenced these thermophysical properties. Overall, the findings demonstrate that andesite sourced at higher elevations possesses superior thermal diffusivity and more favorable heat‑transfer characteristics at elevated temperatures. These results highlight the importance of geological origin in the design, assessment, and selection of natural stone materials for high‑temperature engineering applications.

  İncele
• MakaleAçık Erişim2026Scopus SJRQ1/r/munzur/1239
  Large-eddy simulation of flow over a square prism with moving belts

  You, Rui; Fırat, Erhan

  This three-dimensional (3D) numerical study investigates the feasibility of controlling the intermittently reattaching flow (IRF) by using the moving-surface boundary-layer control (MSBC) method. To this end, a fixed square prism was preferred due to its geometric simplicity and was equipped with moving belts that placed side surfaces close to the trailing edges. The effects of three dimensionless key parameters including velocity ratio (i.e., VR, the ratio of the velocity of the moving belt to the freestream velocity), length ratio (i.e., LR, the ratio of the belt length to the edge length of the square prism), and gap ratio (i.e., GR, the ratio of the spanwise distance between the neighboring belts to the edge length of the square prism) mainly on the aerodynamic characteristics were investigated using large-eddy simulation (LES). The findings suggest that the rise in VR and LR parameters leads to a proportional decrease in the time-averaged drag, 〈CD〉, attributable to their contribution to the linear momentum transfer mechanism by the moving surfaces. This mechanism, firstly, provides an additional thrust to the prism in the opposite direction of the main flow. Secondly, this mechanism increases the base pressure by stretching the shear layers from the leading edges of the prism in the streamwise direction. For LR = 0.4 and VR = 4, a 17 % reduction in 〈CD〉 was observed. Additionally, the root-mean-square (RMS) values of fluctuating drag and lift coefficients, CD-RMS and CL-RMS, have decreased by 71 % and 55 %, respectively. Conversely, the increase in the GR parameter led to an increase in the spanwise distance between each individual moving belt and a reduction in the positive effect of the linear momentum transfer mechanism on the 〈CD〉 reduction. The segmentation of moving belts along the spanwise direction also triggered the vorticity redistribution mechanism concurrently. The study also elucidated the underlying mechanisms that led to the failure of the vorticity redistribution mechanism to adequately reduce the 〈CD〉.

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