ATMOSFERİK BRÜLÖRDE ENJEKTÖR ÇAPI, ENJEKSİYON HIZI VE HAVA GİRİŞ DELİKLERİ SAYISININ HAVA-YAKIT KARIŞMASINA ETKİSİNİN NÜMERİK İNCELENMESİ

Year 2021, Volume: 9 Issue: 4, 995 - 1012, 04.12.2021

Seyda Özbektaş , Bilal Sungur , Bahattin Topaloğlu

https://doi.org/10.36306/konjes.948992

Abstract

Dünya enerji ihtiyacının büyük bir kısmı fosil kökenli kaynaklardan karşılanmaktadır. Ancak fosil enerji kaynaklarının giderek azalması, araştırmacıları mevcut kaynaklara alternatif olabilecek yeni yakıt arayışlarına ve eldeki kaynakları daha verimli kullanmaya yöneltmiştir. Ayrıca enerji üretilirken genelde bir yakma sisteminden faydalanılır ve yakma sisteminin verimi yanma kalitesiyle yakından ilgilidir. Gaz yakıtın durgun hava içine enjekte edildiği ve gereken yakma havasını emmek suretiyle yakma havasını yakıtın kendisinin temin ettiği yakıcılar atmosferik yakıcılar olarak bilinir ve bu yakıcılarda hava-yakıt karışma oranları yanma kalitesini belirlemede önemli bir paya sahiptir. Bu çalışmada örnek bir atmosferik brülörde enjektör çapının ve enjeksiyon hızının hava-yakıt karışmasına etkisi nümerik olarak incelenmiştir. Ayrıca çalışma kapsamında iki, dört, sekiz ve sonsuz hava giriş delikli tasarımların brülördeki hava/yakıt karışmasına etkisi incelenmiştir. Hesaplamalar üç boyutlu olarak gerçekleştirilmiştir. Türbülansın modellenmesinde Standard k-ε modeli kullanılmıştır. Sonuçlar incelendiğinde, enjeksiyon hızının artması sürüklenen hava hızını arttırıcı yönde etki göstermiş, artan enjeksiyon hızıyla birlikte oluşan girdapların da boyutlarının büyüdüğü görülmüştür. Ayrıca hava giriş delik sayısının artmasıyla birlikte havanın içeri daha fazla nüfuz ettiği ve buna bağlı olarak λ değerinin arttığı görülmüştür. Ancak bu artışın önemli seviyelerde olmadığı belirlenmiştir.

Keywords

Atmosferik brülör, Enjektör, Nümerik modelleme

Numerical Investigation of the Effect of Injector Diameter, Injection Velocity and Air Inlet Hole Numbers on Air-Fuel Mixing In Atmospheric Burner

Abstract

The world's energy needs are mostly supplied from fossil sources. However, the gradual decrease in fossil energy resources has led researchers to search for new fuels that can be an alternative to existing resources and to use the available resources more efficiently. In addition, a combustion system is generally used when generating energy and the efficiency of the combustion system is closely related to the combustion quality. Burners in which gaseous fuel is injected into still air and the combustion air supplied by the fuel itself by sucking the required combustion air are known as atmospheric burners, and air-fuel mixing ratios in these burners have an important role in determining the combustion quality. In this study, the effect of injector diameter and injection velocity on air-fuel mixing in a sample atmospheric burner was investigated numerically. Additionally, the effect of designs with two, four, eight and infinite air inlet holes on the air/fuel mixing in the burner was investigated. Calculations were made at three dimensional conditions. Standard k-ε model was used as turbulence model. Results showed that the increase in the injection velocity increased the entrained air velocity, and with the increasing injection velocity vortices size increased. In addition, it has been observed that with the increase in the number of air intake holes, the air penetrates more and consequently the λ value increases. However, it was determined that this increase was not significant.

Keywords

Atmospheric burner, Injector, Numerical modeling

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