TY - JOUR T1 - ChemEqT: A Unified Computational Tool for Predicting Equilibrium Composition and Adiabatic Flame Temperature in Multicomponent Fuel–Air Systems TT - ChemEqT: Çok Bileşenli Yakıt-Hava Sistemlerinde Denge Kompozisyonu ve Adyabatik Alev Sıcaklığını Tahmin Etmek İçin Birleşik Bir Hesaplama Aracı AU - Aydın, Nuri Özgür AU - Kopaç, Mehmet PY - 2025 DA - October Y2 - 2025 DO - 10.47480/isibted.1716739 JF - Isı Bilimi ve Tekniği Dergisi PB - Türk Isı Bilimi ve Tekniği Derneği WT - DergiPark SN - 1300-3615 SP - 325 EP - 334 VL - 45 IS - 2 LA - en AB - This study presents ChemEqT, a computational tool that integrates both Gibbs free energy minimization and the element potential method within a unified framework for determining chemical equilibrium compositions and adiabatic flame temperatures in multicomponent fuel–air gas mixtures. ChemEqT is designed to simplify the complexity of equilibrium combustion calculations and provides users with flexibility in selecting the numerical strategy best suited to their system. The performance of ChemEqT is validated through three case studies involving propane–air and methane–air mixtures. In the first case, simulations of a propane–air system involving 10 species yielded adiabatic flame temperature predictions with a maximum deviation of 0.32% and molar species deviations below 0.77% for CO₂. The second case examines methane–air mixtures enriched with hydrogen, using 52 species, where the maximum deviation was under 0.04%. The third case involves adiabtic flame temperature predictions for 10 different fuel–air mixtures, with deviations below 0.146% for C₃H₆–air. These results establish ChemEqT as a reliable and efficient tool for equilibrium-based combustion analysis, with strong potential for integration into broader energy process simulation frameworks. Its accuracy, modularity, and computational efficiency make it a valuable asset for researchers working in the fields of combustion and energy systems. KW - Adiabatic flame temperature KW - chemical equilibrium KW - combustion modeling KW - gas mixtures N2 - Bu çalışmada ChemEqT, çok bileşenli yakıt-hava gaz karışımlarında kimyasal denge bileşimlerini ve adyabatik alev sıcaklıklarını belirlemek için hem Gibbs serbest enerji minimizasyonunu hem de element potansiyeli yöntemini birleşik bir çerçevede sunan bir hesaplama aracı olarak geliştirilmiştir. ChemEqT, denge yanma hesaplamalarının karmaşıklığını basitleştirmek ve kullanıcılara sistemlerine en uygun sayısal stratejiyi seçme konusunda esneklik sağlamak için tasarlanmıştır. ChemEqT'nin performansı, propan-hava ve metan-hava karışımlarını içeren üç vaka çalışmasıyla doğrulanmıştır. İlk vaka çalışmasında, 10 bileşenin yer aldığı bir propan-hava sisteminin simülasyonları, % 0.32'lik maksimum sapma ve CO₂ için % 0.77'nin altında molar bileşen sapmaları ile adiabatik alev sıcaklığı tahminleri üretmiştir. İkinci vaka çalışmasında, maksimum sapmanın % 0.04'ün altında olduğu 52 bileşen kullanılarak hidrojenle zenginleştirilmiş metan-hava karışımları incelenmiştir. Üçüncü vaka, C₃H₆–hava için % 0.146'nın altında sapmalarla 10 farklı yakıt-hava karışımı için aybatik alev sıcaklığı tahminlerini içerir. Bu sonuçlar, ChemEqT'yi daha geniş enerji proses simülasyon çerçevelerine entegrasyon için güçlü bir potansiyele sahip, denge tabanlı yanma analizi için güvenilir ve verimli bir araç olarak göstermektedir. ChemEqT doğruluğu, modülerliği ve hesaplama verimliliği ile, yanma ve enerji sistemleri alanlarında çalışan araştırmacılar için değerli bir hesaplama aracı olarak kullanılabildiği belirlenmiştir. CR - Annamalai, K., & Puri, I. K. (2006). 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