TÜRBÜLANSLI YANMA İÇİN DÖNDÜRÜCÜNÜN PARAMETRİK ÇALIŞMASI

Abstract

Bu çalışmada döndürücüye ait kanat sayısı, kanat sarım açısı ve kanat uzunluğu ile yakıt giriş çapının yanma odasındaki türbülanslı akış yapısı, yanma verimi ve emisyon değerleri üzerine etkisi araştırılmıştır. Referans alınan döndürücü kanat sayısı (n), kanat uzunluğu (L), kanat sarım açısı (θ) ve yakıt giriş çapı (D2) sırası ile 10, 40 mm, 45°, 19.5 mm’dir. Kanat sayısı (6,8,10,12,14), kanat uzunluğu (0.5L, L, 1.5L, 2L), kanat sarım açısı (30°, 45°, 60°, 75°, 90°, 120°) ve yakıt giriş çapı için (0.5 D2, D2, 1.5 D2, 2 D2) parametrik değerler kullanılarak yeni modeller oluşturulmuştur. Sayısal çalışmalar ANSYS/Fluent 17.2 ticari yazılımı ile gerçekleştirilmiş ve referans alınan deneysel çalışmaya uygun olarak önceden karışmamış yanma modeli tanımlanmıştır. Sayısal yöntem, elde edilen verilerin deneysel veriler ile karşılaştırılması ile doğrulanmıştır. Analizler sonucu olarak kanat sarım açısının alev şekli, kanat uzunluğunun ise alevin simetrik yapısı üzerine önemli etkisinin olduğu bulunmuştur. M04510403900 (θ=45°, n=10, L=40 mm, D2=39.00 mm) modelinde en yüksek ısıl verim elde edilmiş ve % 79.3 olan referans döndürücünün ısıl verimi bu model ile % 93.8’e yükselmiştir. Yanma odası seyreltme delikleri öncesinde CO kütle fraksiyonu değerinin referans döndürücü modelinde 0.002 olduğu ve M04510400975 (θ=45°, n=10, L=40 mm, D2=9.75 mm) modelinde bu değerin 0.018’e yükseldiği tespit edilmiştir.

Keywords

• Döndürücü tasarımı
• Hesaplamalı Akışkanlar Dinamiği
• Kanat sayısı
• Kanat uzunluğu
• Önceden karışmamış yanma modeli
• Sarım açısı
• Yakıt giriş çapı

A PARAMETRIC STUDY ON THE SWIRLER FOR TURBULENT COMBUSTION

Abstract

In this study, the effects of the number of swirler blades, swirler blade wrape angle, swirler blade length and the fuel inlet diameter on the turbulent flow structure, combustion efficiency and emission in a combustion chamber have been investigated. The number of blades (n), the blade length (L), the blade wrape angle (θ) and the fuel inlet diameter (D2) of the swirler blades were taken as 10, 40 mm, 45° and 19.5 mm, respectively. New models were created using the parameters of the blade number (6,8,10,12,14), the blade length (0.5L, L, 1.5L, 2L), the blade wrape angle (30°, 45°, 60°, 75°, 90°, 120°) and the fuel inlet diameter (0.5 D2, D2, 1.5 D2, 2 D2). Numerical analysis were performed using ANSYS/Fluent 17.2 commercial software and non-premixed combustion model was defined according to the referenced experimental study. Numerical method was validated with the comparison of numerical and experimental data. It is concluded that the wrape angle has a significant effect on the flame shape and the blade length on the symmetrical structure of the flame. The highest thermal efficiency was obtained for the model M04510403900 (θ =45°, n=10, L =40 mm, D2=39.00 mm) and the thermal efficiency of the referenced swirler geometry of 79.3% were increased to 93.8% with this model. It has been seen that CO mass fraction value upstream of the dilution holes was 0.002 for referenced swirler model and this value increased to 0.018 for the model M04510400975 (θ=45°, n=10, L=40 mm, D2=9.75 mm).

Keywords

• Swirler design
• Computational Fluid Dynamics
• Blade number
• Blade length
• Non-premixed combustion
• Wrap angle
• Fuel inlet diameter

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