Distributed Regime and Swirler Effects on Methane and Coke Oven Gas Combustion Characteristics

Alparslan Ilbas; Mustafa Bahadır Özdemir; Serhat Karyeyen

Makale detayları

Distributed Regime and Swirler Effects on Methane and Coke Oven Gas Combustion Characteristics

Yazarlar:

Alparslan Ilbas | Mustafa Bahadır Özdemir | Serhat Karyeyen

Yayıncı:

Gazi University

Ana Başlıklar:

Makine Mühendisliğinde Sayısal Yöntemler

Dergi:

Politeknik Dergisi Vol.28 Issue 2, pp.531-544

Belge Tipi:

Makale

Yayın Tarihi:

3/2025

Belge Dili:

İngilizce

Document ID (Org No.):

2001344337

pISSN:

2147-9429

Anahtar kelimeler:

Özet:

 The present study deals with combustion characteristics of methane and coke oven gas for various swirl numbers in a highly internal recirculative combustor under colorless distributed combustion conditions. In order to achieve that, the fuels have been consumed numerically in the combustor at various oxygen concentrations by using a N2 diluent to reduce oxygen concentration in the air. During the modelings, swirl number has been changed from s0 to s1 in an interval of 0.2. In this way, swirler effects on its combustion characteristics have been studied. In order to perform all modelings, the k-ε realizable turbulence model, the PDFMixture Fraction combustion model, and P-1 radiation model have been used. The results showed that decrease in oxygen concentration caused a more uniform temperature field in the combustor along with ultra-low NOx emissions. When the oxygen rate was reduced from 21 to 15, a 9 decrease in the highest temperature reached in the combustion chamber was observed. In addition, a 99 decrease in nitrogen oxide formation was observed. This has been achieved with internal and external colorless distributed regime entrainments. In addition to these, it is concluded that the swirler has affected that combustion took place faster mostly because of better air-fuel mixture in the combustor. It has been observed that the air and fuel mixture occurs faster in the swirler effect, which has effects on the flow characteristics in the combustion chamber and has positive effects on recirculation, which can help to obtain conditions close to distributed combustion conditions in general. For 21 oxygen ratio, nitrogen oxide formation could be reduced by approximately 50 by increasing the swirl number from 0 to 1.

 The present study deals with combustion characteristics of methane and coke oven gas for various swirl numbers in a highly internal recirculative combustor under colorless distributed combustion conditions. In order to achieve that, the fuels have been consumed numerically in the combustor at various oxygen concentrations by using a N2 diluent to reduce oxygen concentration in the air. During the modelings, swirl number has been changed from s0 to s1 in an interval of 0.2. In this way, swirler effects on its combustion characteristics have been studied. In order to perform all modelings, the k-ε realizable turbulence model, the PDFMixture Fraction combustion model, and P-1 radiation model have been used. The results showed that decrease in oxygen concentration caused a more uniform temperature field in the combustor along with ultra-low NOx emissions. When the oxygen rate was reduced from 21 to 15, a 9 decrease in the highest temperature reached in the combustion chamber was observed. In addition, a 99 decrease in nitrogen oxide formation was observed. This has been achieved with internal and external colorless distributed regime entrainments. In addition to these, it is concluded that the swirler has affected that combustion took place faster mostly because of better air-fuel mixture in the combustor. It has been observed that the air and fuel mixture occurs faster in the swirler effect, which has effects on the flow characteristics in the combustion chamber and has positive effects on recirculation, which can help to obtain conditions close to distributed combustion conditions in general. For 21 oxygen ratio, nitrogen oxide formation could be reduced by approximately 50 by increasing the swirl number from 0 to 1.

 The present study deals with combustion characteristics of methane and coke oven gas for various swirl numbers in a highly internal recirculative combustor under colorless distributed combustion conditions. In order to achieve that, the fuels have been consumed numerically in the combustor at various oxygen concentrations by using a N2 diluent to reduce oxygen concentration in the air. During the modelings, swirl number has been changed from s0 to s1 in an interval of 0.2. In this way, swirler effects on its combustion characteristics have been studied. In order to perform all modelings, the k-ε realizable turbulence model, the PDFMixture Fraction combustion model, and P-1 radiation model have been used. The results showed that decrease in oxygen concentration caused a more uniform temperature field in the combustor along with ultra-low NOx emissions. When the oxygen rate was reduced from 21 to 15, a 9 decrease in the highest temperature reached in the combustion chamber was observed. In addition, a 99 decrease in nitrogen oxide formation was observed. This has been achieved with internal and external colorless distributed regime entrainments. In addition to these, it is concluded that the swirler has affected that combustion took place faster mostly because of better air-fuel mixture in the combustor. It has been observed that the air and fuel mixture occurs faster in the swirler effect, which has effects on the flow characteristics in the combustion chamber and has positive effects on recirculation, which can help to obtain conditions close to distributed combustion conditions in general. For 21 oxygen ratio, nitrogen oxide formation could be reduced by approximately 50 by increasing the swirl number from 0 to 1.

 Bu çalışma, renksiz dağıtılmış yanma koşulları altında yüksek düzeyde iç resirkülasyonlu bir yanma odasında çeşitli girdap sayıları için metan ve kok fırını gazının yanma özelliklerini ele almaktadır. Bunu başarmak için, havadaki oksijen konsantrasyonunu azaltmak amacıyla N2 seyrelticisi kullanılarak yakıtlar yanma odasında çeşitli oksijen konsantrasyonlarında sayısal olarak tüketilmiştir. Modellemeler sırasında girdap sayısı 0.2 aralıklarla s0dan s1e kadar değiştirilmiştir. Bu şekilde yanma özellikleri üzerindeki girdap etkileri incelenmiştir. Tüm modellemelerin gerçekleştirilebilmesi için k-ε Realizable türbülans modeli, PDFMixture Fraction yanma modeli ve P-1 radyasyon modeli kullanılmıştır. Sonuçlar, oksijen konsantrasyonundaki azalmanın, ultra düşük NOx emisyonlarıyla birlikte yanma odasında daha düzgün bir sıcaklık alanına neden olduğunu ortaya koymuştur. Oksijen oranının 21den 15e düşürülmesi ile birlikte yanma odasını içerisinde ulaşılan en yüksek sıcaklıkta 9 oranında düşüş gözlemlenmiştir. Bununla birlikte azot oksit oluşumunda 99 oranında düşüş gözlemlenmiştir. Bu durum, iç ve dış renksiz dağıtılmış rejim resirkülasyonun birlikte olmasıyla başarılmıştır. Bunlara ek olarak, yanma odasındaki hava-yakıt karışımının daha iyi olması nedeniyle, girdap üretici kullanımının yanmanın daha hızlı gerçekleşmesini etkilediği sonucuna varılmıştır. Girdap oluşturucu etkisinde hava ve yakıt karışımının daha hızlı gerçekleştiği, bunun yanma odası içerisinde akış karakteristiği üzerine etkileri olduğu ve genel olarak dağıtılmış yanma şartlarına yakın koşulların elde edilmesine yardımcı olabilecek şekilde resirkülasyona olumlu etkileri olduğu gözlemlenmiştir. 21 oksijen oranı için, girdap sayısının 0dan 1e çıkarılması ile azot oksit oluşumu yaklaşık 50 oranında düşürülebilmiştir.

Makale detayları

Distributed Regime and Swirler Effects on Methane and Coke Oven Gas Combustion Characteristics

Yazarlar:

Alparslan Ilbas | Mustafa Bahadır Özdemir | Serhat Karyeyen

Yayıncı:

Gazi University

Ana Başlıklar:

Makine Mühendisliğinde Sayısal Yöntemler

Dergi:

Politeknik Dergisi Vol.28 Issue 2, pp.531-544

Belge Tipi:

Makale

Yayın Tarihi:

3/2025

Belge Dili:

İngilizce

Document ID (Org No.):

2001344337

pISSN:

2147-9429

Distributed Regime

Swirler

Combustion

Ultra-low NOXDağıtılmış Rejim

Girdap Üretici

Yanma

Ultra-düşük NOX

Sayı

Makale detayları

Yazarlar: Alparslan Ilbas | Mustafa Bahadır Özdemir | Serhat Karyeyen

Yayıncı: Gazi University

Ana Başlıklar: Makine Mühendisliğinde Sayısal Yöntemler

Dergi: Politeknik Dergisi Vol.28 Issue 2, pp.531-544

Belge Tipi: Makale

Yayın Tarihi: 3/2025

Belge Dili: İngilizce

Document ID (Org No.): 2001344337

pISSN: 2147-9429

Sayı

Yazarlar:

Alparslan Ilbas | Mustafa Bahadır Özdemir | Serhat Karyeyen

Yayıncı:

Gazi University

Ana Başlıklar:

Makine Mühendisliğinde Sayısal Yöntemler

Dergi:

Politeknik Dergisi Vol.28 Issue 2, pp.531-544

Belge Tipi:

Makale

Yayın Tarihi:

3/2025

Belge Dili:

İngilizce

Document ID (Org No.):

2001344337

pISSN:

2147-9429