Differential diffusion and pressure effects on heavily sooting 2D Kerosene/Air diffusion flames

Öz

For heavily sooting Kerosene/Air flames the ideal gas law (IGL) and a real gas (RGL) equation of state (EOS) models have been employed to study the assumption of the unity Lewis (Le) number effects on the soot production/oxidation processes for four different operating pressures. An MPI FORTRAN code containing a semi-global soot production/oxidation model for a reduced Kerosene/Air mechanism (29-step, 10 species) has been used to create 2B DSS data. For the aim of verifying the applicability of the unity Le assumption for Kerosene/Air flames comparisons between unity and non-unity Lewis (Le) number flame predictions must possess statistically similar trends in not only the flame structure but also the soot properties. 1, 5 10 and 35 atm analyses of 2D DNS flame predictions of the RGL and the IGL EOS models have unveiled that the EOS coupled models with the unity-Le number mis-predicts the soot properties and the mean flame temperatures.

Anahtar Kelimeler

• Kerosene
• soot
• DNS
• real gas equations
• generalized diffusion
• Ideal Gas Law
• diffusion flames

Yüksek derecede kurum üreten 2B Gazyağı/Hava difüzyon alevleri üzerinde diferansiyel yayılımın ve basıncın etkileri

Öz

Bu çalısmada, dört farklı ortam basıncında kurum, oluşum ve yıkım süreçlerini incelemek amacıyla, yoğun kurum üreten Gazyağı/Hava alevleri, gerçek gaz (GG) ve ideal gaz (İG) hal denklemleri ve Lewis (Le) sayısının bir olarak kabul edildiği modeller ele alınmıştır. Yarı-genel kurum oluşum ve yıkım modelini içeren indirgenmiş Gazyağı/Hava mekanizması (29-adım, 10 çeşit gaz) 2 boyutlu (2B) Direk Sayısal Simülasyon (DNS) verilerini oluşturmak için MPI FORTRAN ile kodu yazılmış bir program kullanılmıştır. Le sayısının bire eşit kabul edildiği alev tahminlerinin, Le sayısının bire eşit olmadığı (genelleştirilmiş difüzyon) durumların sayısal sonuçlarından elde edilen alev yapısı ve kurum özelliklerinin istatiksel olarak benzerlik sağlayıp sağlamadığı araştırılmıştır. Bu bağlamda yapılan çalışmanın sonucunda, ortam basınçları 1, 5, 10 ve 35 atm olan Le sayısının bir olarak kabul edildiği GGLE ve İGLE modelleri ile üretilmiş 2B DNS alev tahminlerinin kurum özelliklerinin ve alev yapılarının yanlış hesaplanmasına yol açtığı belirlenmiştir.

Anahtar Kelimeler

• Gazyağı
• kurum
• DNS
• gerçek gaz
• genelleştirilmiş difüzyon
• İdeal Gaz Kanunu
• difüzyon alevleri

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