Numerical Simulation of Premixed Turbulent Methane Combustion in a Multi-Inlet Cyclone Combustor

Öz

The multi-inlet cyclone combustion chamber simulated in this study has 14 tangential gas/air inlets, each with an internal diameter of 9.525 mm, and is inclined 30° towards the front end of the combustion chamber in 2 symmetrical rows of seven. This study used CFD code to numerically simulate a multi-inlet cyclone combustor fueled by methane. The standard k-Ɛ model was chosen to simulate turbulent flow. Eddy Dissipation was used to simulate the combustion of a premixed mixture. The simulation was carried out for an air:fuel ratio (φ) of 1.0. The design velocity at the entrance to the combustion chamber is 20 m/s. In all cases, the inlet gas temperature was assumed to be T=300 K. The number of iterations was 3000.The other physical constans were taken from the literature. The computational default value was used for the operating pressure. The results of the study showed that the proposed cyclonic combustor provides better fuel mixing, increases the residence time of the fuel in the combustor, achieves a uniform temperature field and reduces emissions.

Anahtar Kelimeler

• The multi-inlet cyclone
• CFD modelling
• Methane combustion

Çok Girişli Siklonlu Yakıcıda Türbülanslı Ön Karışımlı Metan Yanmasının Sayısal Simülasyonu

Öz

Bu çalışmada simüle edilen çok girişli siklon yakıcı, her biri 9.525 mm iç çapa sahip 14 teğet gaz/hava girişine sahiptir ve yedili 2 simetrik sıra halinde yanma odasının ön ucuna doğru 30° eğimlidir. Bu çalışmada metanla beslenen çok girişli siklonlu bir yakıcının sayısal simülasyonunu yapmak için CFD kodu kullanılmıştır. Türbülanslı akışı simüle etmek için standart k-Ɛ modeli seçilmiştir. Önceden karıştırılmış bir karışımın yanmasını simüle etmek için Eddy Dissipation kullanılmıştır. Simülasyon, 1,0 hava:yakıt oranı (φ) için gerçekleştirilmiştr. Yanma odasının girişindeki hız 20 m/s'dir. Tüm durumlarda giriş gazı sıcaklığının T=300 K olduğu varsayılmıştır. İterasyon sayısı 3000'dir. Diğer fiziksel sabitler ise literatürden alınmıştır. Çalışma basıncı için hesaplamalı varsayılan değer kullanılmıştır. Çalışmanın sonuçları, önerilen siklonik yakıcının daha iyi yakıt karışımı sağladığını, yakıtın yanma odasında kalma süresini arttırdığını, üniform bir sıcaklık alanı elde ettiğini ve emisyonları azalttığını göstermiştir.

Anahtar Kelimeler

• Çok girişli siklon yakıcı
• CFD modelleme
• Metan yanması

Kaynakça

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