Strut Tabanlı Scramjet Yanma Odasında Dişli Strut Uygulamasının Yanma Performansına Etkilerinin Nümerik İncelenmesi

Abstract

Bu çalışmada, scramjet motorunun yanma odasında daha iyi yakıt dağılımı ve alev kararlığı elde etmek amacıyla tasarlanan dişli strut konfigürasyonlarının yanma sürecine etkileri iki boyutlu nümerik analiz ile incelenmiştir. Nümerik çalışmanın türbülans modellemesinde Shear Stress Transport (SST) k-ω modeli kullanılmış, yanma modellemesinde Eddy Dissipation Concept (EDC) modeli tercih edilmiştir. Ayrıca, ideal gaz yasası, tür taşınım denklemleri ve Reynolds Ortalamalı Navier-Stokes (RANS) denklemleri kullanılmıştır. Bu çalışma kapsamında, strut üzerindeki dişlerin ve diş konumlarının süpersonik akışta yakıt-hava etkileşimi ve yanma performansı üzerindeki etkileri Referans Model (DLR scramjet) ile karşılaştırmalı olarak değerlendirilmiştir. Strut üzerindeki dişlerin etkisiyle sık yapıda şok trenlerinin oluştuğu, akışın daha etkin sıkıştırıldığı, yakıt-hava etkileşiminin arttığı ve bunun da hidrojen yanmasını hızlandırdığı ve tüm bu sürecin yanmaya olumlu katkı sağladığı gözlemlenmiştir. Gerçekleştirilen iyileştirmeler neticesinde, ideal karıştırma uzunluğu Referans Model’e kıyasla %33 kısalmış ve buna paralel olarak yanma verimi Referans Model’e göre %17 artarak yaklaşık %75 seviyesine ulaşmıştır. Bununla birlikte, toplam basınç kaybı Referans Model’e kıyasla %10 artış göstererek yaklaşık %22 değerine yükselmiştir.

Keywords

• Scramjet yanma odası
• Strut enjeksiyonu
• Yanma verimi
• Süpersonik akış
• Hesaplamalı akışkanlar dinamiği

Ethical Statement

Yazarlar, bu çalışmanın hazırlanması sırasında herhangi bir çıkar çatışması içinde olmadıklarını beyan ederler.

Numerical Investigation of the Effects of a Toothed Strut Application on Combustion Performance in a Strut-Based Scramjet Combustor

Abstract

In this study, the effects of toothed strut configurations, designed to achieve improved fuel distribution and enhanced flame stability in the scramjet combustor, on the combustion process were investigated through two-dimensional numerical analyses. For turbulence modeling, the SST (Shear Stress Transport) k–ω model was employed, while the EDC (Eddy Dissipation Concept) model was adopted for combustion modeling. In addition, the ideal gas law, species transport equations, and Reynolds-Averaged Navier–Stokes (RANS) equations were utilized. Within the scope of this work, the effects of the teeth on the strut and their positioning on fuel–air interaction and combustion performance under supersonic flow conditions were evaluated comparatively against a Reference Model (DLR scramjet). The presence of teeth on the strut was observed to induce closely spaced shock trains, leading to more effective flow compression and enhanced fuel–air interaction, which in turn accelerated hydrogen combustion and contributed positively to the overall combustion process. As a result of these improvements, the ideal mixing length was reduced by 33% compared to the Reference Model, and correspondingly, the combustion efficiency increased by 17%, reaching approximately 75%. However, the total pressure loss increased by about 10% relative to the Reference Model, rising to approximately 22%.

Keywords

• Scramjet combustor
• Strut injection
• Combustion efficiency
• Supersonic flow
• Computational Fluid Dynamics

Ethical Statement

The authors declare that they have no conflicts of interest in the preparation of this study.

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