Araştırmacılar(8)

• Atasoy, Vehbi Emrah
• Aydın, Emre
• Cam, O.
• Can, Erol
• Ercümen, K.M.
• Sivri, Ilker
• Yalin, Gorkem
• Yilmaz, Harun

• ArticleYalnız künye2026/r/ebyu/18238
  Adaptive hybrid control algorithm for integrated wind-solar energy systems: Enhancing efficiency and minimizing environmental impact

  Can, Erol

  This study introduces a three-tier adaptive control strategy designed for hybrid wind - solar energy systems, with the goal of optimizing energy capture, stabilizing the DC bus voltage, and enhancing overall system performance under varying environmental conditions. The control framework incorporates a TSR-based Maximum Power Point Tracking (MPPT) method for the wind turbine, a temperature-sensitive Perturb-and-Observe (P&O) MPPT for the photovoltaic array, and a real-time energy coordination system that dynamically adjusts the power allocation between wind and solar sources based on their instantaneous availability. A conventional Proportional-Integral (PI) controller manages the DC bus voltage, minimizing fluctuations and ensuring seamless integration with energy storage or the grid. The proposed approach is adaptable to both off-grid and grid-connected microgrids and is computationally efficient for real-time application. Simulation results from four typical scenarios - including high wind/low solar, low wind/high solar, intermittent generation, and balanced generation - show system efficiencies consistently exceeding 92%, along with a substantial reduction in voltage ripple when compared to traditional MPPT techniques. These findings validate the effectiveness of the coordinated control strategy in maintaining power quality, system reliability, and stable energy output, offering a scalable and practical solution for integrating renewable energy into microgrid systems.

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• ArticleYalnız künye2026/r/ebyu/18143
  UAV DC Motor behaviors control using new hybrid PSO-fuzzy logic with a dynamic error based optimization

  Can, Erol

  This study introduces a novel and comprehensive control architecture for DC motor speed regulation in unmanned aerial vehicles (UAVs), leveraging a hybrid Particle Swarm Optimization-Fuzzy Logic (PSO-FL) strategy. UAV platforms inherently exhibit highly nonlinear, time-varying, and uncertain dynamics, which often challenge the efficacy of traditional control techniques such as Proportional-Integral-Derivative (PID) controllers and conventional fuzzy logic systems. To overcome these limitations, a dual-layer PSO-FL controller is proposed, wherein the PSO algorithm is utilized to optimize both fuzzification and defuzzification parameters, thereby enhancing controller adaptability and precision. Moreover, a Centralized Agent Optimization (CAO) framework is integrated to accelerate convergence and improve overall computational efficiency. The proposed controller dynamically adjusts membership functions and rule weights in real time, enabling robust, stable, and rapid system responses even under sudden aerodynamic perturbations and variable payload conditions. Extensive simulation and experimental validations confirm the superior performance of the proposed method over classical PID, PSO-tuned PID, and conventional fuzzy logic controllers, demonstrating faster rise times, reduced overshoot, and minimized steady-state error. These findings significantly advance the development of intelligent UAV control systems by effectively combining swarm intelligence with human-like reasoning methodologies.

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• ArticleYalnız künye2026/r/ebyu/10827
  Hybrid Plasma–GaNSemiconductor Trigger Switch for Ultra-fast High-power Pulsed Applications: a Numerical Study

  Can, Erol

  Abstract: This study presents a numerical investigation of a Hybrid Plasma–Semiconductor Trigger Switch (HPTS) combining a GaN-based driver with a low-pressure pseudo-spark discharge channel. The objective is to evaluate the potential of integrating deterministic semiconductor switching with high-current plasma conduction for pulsed-power applications. A dynamic simulation model was developed to capture the interaction between time-dependent plasma conductivity, GaN driver dynamics, and circuit parasitics. Simulated results indicate that the HPTS can achieve sub-nanosecond jitter (less than 0.5 ns), bidirectional current conduction up to ±17 kA, and current rise rates of 300–400 A/ns. Performance is shown to improve with lower discharge pressures and faster driver rise. Comparative analysis with reported experimental data for thyratron and pseudo-spark switches demonstrates that the simulated HPTS achieves faster switching, higher timing precision, and improved energy transfer efficiency (96–97%). These findings highlight the potential of HPTS architectures for high-speed pulsed-power systems, while clarifying that the reported results are derived from numerical simulations rather than physical experiments.

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• ArticleYalnız künye2026/r/ebyu/10593
  Experimental and numerical thermo-hydraulic performance optimization of fin and tube heat exchanger using genetic algorithms

  Tepe, Ahmet Ümit; Kuru, Muhammet Nasıf; Yilmaz, Harun

  This study focuses on the multi-objective optimization of fin and tube heat exchangers to maximize the Thermal Performance Factor and minimize the Volume . A novel fin design is proposed and integrated onto the tube surfaces to enhance thermo-hydraulic performance. The numerical simulations were conducted using Computational Fluid Dynamics with the conjugate heat transfer method, while the optimization framework was established on modeFRONTIER using a Multi-Objective Genetic Algorithm (MOGA-II). The numerical model was validated against experimental data in this study and existing literature data. The optimization process investigated various fin parameters, (Dwing, Dring, αback,αfront and Gwing), alongside heat exchanger design parameters (ST and SL) and inlet velocity (Vinlet) including 0.3–10 m/s. A total of 1271 design points were evaluated, resulting in 998 feasible configurations and 24 distinct Pareto-optimal designs. The Pareto-optimal Design set yielded TPF values ranging from 1.09 to 1.66. The results highlight the typical trade-off between thermal performance and heat exchanger Volume . Higher TPF values generally correspond to larger volumes, with Design ID 1 achieving the maximum TPF (1.66) but also the largest volume. Conversely, designs with smaller volumes (Design IDs 22–24) exhibit lower TPF values (≈1.09–1.13). Even among designs with the same volume and inlet velocity, variations in fin geometry significantly affect thermal performance. Therefore, designs with higher TPF are preferable when thermal efficiency is the priority, while more compact designs are suitable when minimizing volume is the main goal.

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• ArticleYayıncıda açık erişim2025/r/ebyu/19556
  Yurtiçi Uçuşlarda Farklı Uçak Modellerinin Emisyon Etkilerinin Analizi İçin Gelişmiş Modelleme Araçlarının Kullanılması

  Atasoy, Vehbi Emrah

  Havacılık sektörü, uçuş operasyonları sırasında oluşan gaz ve partikül madde emisyonlarının hassas bir şekilde ölçülmesi ve değerlendirilmesi yoluyla çevresel sürdürülebilirlik hedeflerine ulaşabilir. Araştırmada, aynı sayıda yolcu talebini karşılayacak geniş ve dar gövdeli uçaklar kullanarak İstanbul Sabiha Gökçen Havalimanı (LTFJ) ile Antalya Havalimanı (LTAI) arasında gerçekleştirilen farklı senaryolar üzerinden operasyonel ve çevresel etkileri analiz edilmektedir. Çalışma, EUROCONTROL'ün IMPACT web tabanlı platformu ve analiz için gerekli bilgileri sağlayan BADA veritabanı gibi araçlar kullanılarak gerçekleştirilmektedir. Çalışma kapsamında elde edilen sonuçlar, geniş gövdeli uçağın LTAI-LTFJ ve LTFJ-LTAI uçuşlarında ortalama 17796 kg CO₂ emisyona neden olduğunu göstermektedir. Buna karşılık, ilgili rotalarda iki dar gövdeli uçak kullanılarak aynı sayıda yolcu taşındığında ise toplam 12597 kg CO₂ emisyonu oluşmaktadır. Bu sonuçlar, uçak tipinin toplam emisyon seviyelerinde önemli bir rol oynadığının bir örneğidir ve dar gövdeli uçakların kısa mesafeli uçuşlarda karbon salınımını azalttığını vurgulamaktadır. Bu çalışma, operasyonel ve çevresel sürdürülebilirliğe ulaşmada uçak seçiminin öneminin altını çizerek, yakıt tüketimini ve emisyonları düşürmeyi planlayan bir havayolunun, web tabanlı modelleme teknolojisini kullanarak filo planlama stratejilerini daha etkili hale getirebileceğini göstermektedir.

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• ArticleYayıncıda açık erişim2025/r/ebyu/12053
  Combustion and emission characteristics of laser-ignited pure methane in a rapid compression machine

  Yilmaz, Harun; Schröder, Lukas; Hillenbrand, Thomas; Brüggemann, Dieter

  In this study, effects of number of consecutive laser ignition pulses on combustion and particle emission characteristics of CH4/Air mixtures were investigated in a rapid compression machine (RCM) by using a passively Q-switched Nd:YAG laser ignitor. To that end, ignition kernel formation and flame evolution characteristics were analyzed with the instrumentality of a high-speed camera (Schlieren setup), while combustion and emission properties were examined by measuring pressure and particulate emissions, respectively. The variation of pressure was also recorded to calculate (with a MATLAB code) indicated work, indicated mean effective pressure and efficiency. Results of this study revealed the linear dependence of ignition possibility to the number of pulses. Ignition possibility increased with the increasing number of pulses. It was 72.72% at 1 pulse and became 92.10% at three pulses. However, number of pulses differently affected other measured or calculated parameters. Depending on the number of pulses, improvements and deteriorations were observed in performance metrics.

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• CorrectionAçık Erişim2025/r/ebyu/11312
  Correction to: Combustion and emission characteristics of laser-ignited pure methane in a rapid compression machine (Journal of the Brazilian Society of Mechanical Sciences and Engineering, (2025), 47, 2, (95), 10.1007/s40430-025-05415-1)

  Yilmaz, Harun; Schröder, Lukas; Hillenbrand, Thomas; Brüggemann, Dieter

  The article “Combustion and emission characteristics of laser-ignited pure methane in a rapid compression machine”, written by Harun Yilmaz, Lukas Schröder, Thomas Hillenbrand and Dieter Brüggemann was originally published under exclusive license to The Author(s), under exclusive licence to The Brazilian Society of Mechanical Sciences and Engineering 2025. As a result of the subsequent decision to publish the article under the open access model, the article’s copyright notice was changed on 08 May 2025 to © The Author(s) 2025 and the article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The original article has been corrected.

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• ArticleYalnız künye2025/r/ebyu/11223
  Drag and thrust calculation of a turbofan engine for medium-range aircraft using flight data recorder data

  Aydın, Emre; Ermeydan, Ahmet; Turan, Onder

  Efficient fuel use is crucial for optimizing aircraft performance, especially in medium-range commercial operations. This study introduces a dynamic thrust-drag modeling technique for a narrow-body jet aircraft powered by a CFM56-7B turbofan engine. It aims to explore the relationship between thrust and fuel consumption using real-world flight data. A physics-based model estimates thrust and drag forces by incorporating parameters such as flap angle, pitch angle, altitude, ground speed, and landing gear position. These parameters are extracted from the Flight Data Recorder (FDR) across multiple Boeing 737 flights. The analysis reveals a strong correlation between fuel flow and thrust, with drag values for flap angles of 15°, 30°, and 40° consistently ranging between 5000 and 10,000 lbf. This study is significant as it enables precise thrust calculations across various flight phases using FDR data. Notably, the thrust force calculated independently of fuel consumption correlates strongly with fuel flow. The findings from this analysis will enhance aero engine functionality and contribute to reducing aircraft energy consumption and emissions.

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• ArticleAçık Erişim2025/r/ebyu/11141
  Study of the effect of concentration and grain size of nano-silica on the impact energy absorption of impregnated glass fibers

  Ercümen, Kadir Münir; Ceylan, Alpertunga; Aşkan, Abdulhalim; Aydin, Murat

  This study investigates the low-velocity impact performance of glass fabrics impregnated with shear thickening fluids, with a focus on the effects of silica particle size and concentration. STFs were synthesized using four different average particle sizes (16 nm, 15–35 nm, 55–75 nm, and 200 nm) at three weight concentrations (40 wt.%, 52.5 wt.%, and 65 wt.%). The resulting liquids were applied to four-layer woven glass fabrics to produce twelve composite samples. All specimens were subjected to dynamic impact testing at 40 J of energy using a 20-mm hemispherical impactor. The results showed that both particle size and concentration had a significant impact on the absorption of impact energy. Sample C65, containing 55–75 nm particles at 65% w/w, showed the highest improvement in absorbed energy with a 98.1% increase over the clean weave. Interestingly, the energy absorption behavior varied with concentration for particles of varied sizes. While energy absorption improved with increasing concentration for 16 nm particles, a decrease was observed for particles ranging from 15 to 35 nm in diameter. These results highlight the critical role of optimizing STF composition, particularly nanoparticle size and concentration in enhancing the impact resistance of flexible composite fabrics. Building on this, the present work offers a systematic experimental framework that contributes to the development of advanced STF-enhanced materials for flexible impact protection applications.

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• ArticleYalnız künye2025/r/ebyu/11002
  Experimental Investigation of Ballistic Impact Performance of Composite Structures Prepared by Shear Thickening Fluid Impregnation Into Aramid, Uhmwpe, and Hybrid Fabrics

  Ercümen, K.M.; Aydin, M.

  This study presents soft armor design strategies with composite samples produced by impregnating STF into aramid, ultra-high molecular weight polyethylene (UHMWPE) and hybrid fabric types. STF was made by dispersing silica nanoparticles in polyethylene glycol at 40 weight% (wt%). The effects of fabric types and hybrid fabric arrangement sequences on energy absorption were experimentally investigated using a single-stage gas gun system. STF-treated fabrics demonstrated a significant increase in energy absorption compared to non-STF-treated fabrics. The extent of this increase varies depending on the fabric type. STF impregnation was found to be more effective in woven aramid fabric, resulting in a 72.7% increase in energy absorption compared to neat fabric. In contrast, STF impregnation of unidirectional UHMWPE fabric led to only a 3.3% increase. In addition to enhancing energy absorption, STF impregnation also demonstrated that altering the fabric arrangement sequence in hybrid samples influences energy absorption. The H3 hybrid sample, consisting of 15 layers of aramid fabric and 15 layers of UHMWPE fabric, exhibited the highest energy absorption. For practical applications in soft body armor design, the effect of fabric arrangement sequence should be considered.

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