| OCR Text |
Show I.INTRODUCTION The process of the combustion inside the swirling combustor is quite complex due to involve simultaneous heat , mass and momentum transfer and chemical reaction. The flows and mixing condition between air and fuel droplets in the reaction zone, especially adjacent to fuel nozzle tip zone, have a significant influence on ignition, flame-holding, flame stability, temperature distribution and the compositions of the burning gas [1]. In general,the characteristics of the swirling flame is commonly used in gas turbine combustors, industrial furnaces etc. to provide flame stability and a good combustion efficiency. The flame pattern and combustion characteristics are determined by the strength of the swirling flow. Therefore,It is a very practical problem to solve, how to find out the optimal swirl strength for desired combustor, for a combustor designers. Recently, although numerous models of swirling liquid fueled combustors have been reported and some empirical correlations of swirling combustion systems have been developed . However, the understanding of liquid-spray burning is insufficient to permit the quantitative predictionson the performance of the swirl-induced combustors. The aims of this experimental work is to study the effects of the swirling flow on the liquid-fuel spray flames. In the present inve~tigation, the flame pattern and combustion flow species concentrations were measured using direct photography and on-line gas analyser respectively. The swirl numbers were changed from 0.3 to 1.2 by the annular vane swirler. 2.EXPERIMENTAL SET-UP Figure 1 illustrated the inlet system and the combustor configuration. The airflow was supplied with an air tank. The fuel was pressurized by high pressure nitrgeon and was injected into combustor chamber. The test combustor model was composed of a 32-mm replaceable annular vane (10 blades) swirler and stainless steel circular chamber. The taps for sampling probe and K-type thermocouple were machined onto the combustor wall, beginning at X/D = 0.25 from the inlet plane. - 1 - |
