Investigation of the Flow Characteristics Occurring in Flame Stabilization Processes

Influence of struts on cavity at subsonic speeds: Flow characteristics

Proceedings of the Institution of Mechanical Engineers Part G Journal of Aerospace Engineering ◽

10.1177/0954410019843726 ◽

2019 ◽

Vol 233 (14) ◽

pp. 5369-5379 ◽

Cited By ~ 6

Author(s):

Junjie Miao ◽

Yuxin Fan

Keyword(s):

Exchange Rate ◽

Residence Time ◽

Mass Exchange ◽

Three Dimensional ◽

Flow Characteristics ◽

Critical Length ◽

Flame Stabilization ◽

Combined Cycle ◽

Structure Parameters ◽

Closed Cavity

Cavity–strut combined flame holder is a promising choice for turbine-based combined cycle engines with its excellent fuel distribution and flame stabilization. In this paper, the effects of the strut structure parameters on the flow characteristics in the cavity were investigated by using particle image velocimetry and numerical simulation. Experimental and numerical results show that the struts induce complex three-dimensional flow patterns, which have a significant influence on the cavity transverse vortex. The relative position between the cavity and the strut influences the critical length-to-depth ratio of the open cavity reverting to the closed cavity. The mass exchange rate of the cavity decreases with the increase in the space between the cavity and the struts, while it increases with the strut inclination angle increases. The variation law of mean cavity residence time with the structure parameters is exactly opposite to that of the mass exchange rate. Compared with a single cavity, at a high subsonic speed, the cavity–strut combined structure has the advantage of increasing the mass exchange rate and cavity residence time simultaneously.

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Technical Applicability of Low-Swirl Fuel Nozzle for a Liquid-Fueled Industrial Gas Turbine Combustor

Volume 2: Combustion, Fuels and Emissions, Parts A and B ◽

10.1115/gt2012-68662 ◽

2012 ◽

Author(s):

Masamichi Koyama ◽

Shigeru Tachibana

Keyword(s):

Gas Turbine ◽

Flow Characteristics ◽

Axial Direction ◽

Flame Stabilization ◽

Axial Position ◽

Axial Distance ◽

Gas Turbine Combustor ◽

Lifted Flame ◽

Fuel Nozzle ◽

Industrial Gas Turbine

This paper explores the technical applicability of a low-swirl fuel nozzle designed for use with a liquid-fueled industrial gas turbine combustor. Particle image velocimetry was applied to measure nozzle flow fields with an open methane-air premixed flame configuration. Herein we discuss the effects of the chamfer dimensions of the nozzle tip on flow characteristics. The profiles indicate parallel shifts in axial direction that depend on chamfer dimensions. When velocity is normalized by bulk velocity and plotted against axial distance from the virtual origins, the profiles are consistent. This means that chamfer dimensions primarily affect the axial position of the flame, while keeping other flow characteristics, such as global stretch rate, unchanged. Then, the atmospheric combustion test was conducted with kerosene in a single-can combustor. Lifted flame stabilization was confirmed by observing the flames through a window. Lastly, an engine test was performed to assess the technical applicability of the fuel nozzle under real engine conditions. The engine testbed was a 290 kW simple-cycle liquid-fueled gas turbine engine. The configurations of the fuel nozzle were consistent with the ones used in the PIV and the atmospheric combustion test. Wall temperatures close to the fuel nozzle exit were within the acceptable range, even without the cooling air required with conventional combustors. This is an advantage of the lifted flame stabilization technique. NOx emissions were below maximum levels set under current Japanese regulations (<84 ppm@15% O2). In sum, the proposed fuel nozzle design shows promise for use with liquid-fueled industrial gas turbine engines.

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