主燃级喷嘴和燃油分级后雾化特性实验研究

Experimental Investigation on Spray Characteristic of Main Injector and Fuel Grade Ratio

关键词:  高温升主燃烧室  三级旋流器  主燃级  燃油分级  雾化特性

Key words:  High temperature rise combustor  Triple swirler  Main stage  Fuel grade  Spray characteristic

摘要:

为优化高温升主燃烧室燃烧性能，对三级旋流主燃烧室开展雾化特性试验研究。预燃级喷嘴采用离心喷嘴压力雾化和气动雾化相结合，主燃级采用预膜式气动雾化。试验采用相位多普勒粒子分析仪对主预燃级喷嘴和燃油分级后的雾化特性进行研究，对比分析了不同头部压降和燃油流量在不同轴向截面和径向位置的液滴粒径分布，并利用高速摄像对不同工况下的喷雾形态进行了记录。试验结果表明：主燃级油雾粒径为50~80μm，气液比达到3.5即可达到良好的雾化水平。随着轴向距离延长，喷雾粒径变大，喷雾浓度变得均匀。燃油分级比增加可降低整体粒径约10μm，且主要影响中心区域，对雾锥外侧粒径影响不大。

Abstract:

In order to optimize combustion performance of high temperature rise combustor， the spray characteristic of triple swirler combustor was experimentally studied. The pilot stage of centrifugal atomizer adopted pressure atomization and air atomization. The main stage adopted prefilming air atomization. Phase Doppler particle analyzer was used to study on spray characteristics of main injector and fuel grade ration. Sauter mean diameter was measured at different head pressure drop and fuel mass flows at different axial distances and radial distances. High speed photography was also used to take spray pictures of different conditions. The experimental results show that the Sauter mean diameter distribution of main injector spray is between 50~80μm. Good atomization can be achieved when air-liquid ratio is bigger than 3.5. With the increase of axial distance， the diameter of droplets increases and fuel concentration becomes uniform. When fuel grade ratio increases， the diameter of droplets decreases about 10μm， the area of influence is concentrated in the central area， the periphery of spray is less impacted on.