摘要
试验研究了不同管路结构对燃油结焦性能的影响,结果表明,在1 000 K、150 m/s来流条件和400 K、0.5 m/s燃油条件下,减小弯管角度和突扩管路的突扩尺寸可以降低结焦附着,且在对管路加热的初始阶段中,结焦量随时间增加会出现波动,在加热15 min时管壁结焦量达到最大,壁面上部分结焦的脱落使结焦量降低。随后,采用试验与数值模拟相结合的方法研究了喷嘴和喷嘴帽罩结构对热防护特性的影响。结果表明,主、副油路同心布置的喷嘴具有最好的热防护效果,在所试验工况下最高可降低湿壁温度近50%,甚至优于带空气隔热层的模型。而喷嘴帽罩对喷嘴出口油温的降低有限,但减小帽罩与喷嘴体的接触或在接触面处填充低热导率的材料仍是有效的改进措施,可降低出口油温约5 K。研究结果对喷嘴的热防护设计具有指导作用。
The deposition performance of tubes with different structures was studied experimentally, And the results showed that when the inflow temperature, inflow velocity, fuel inlet temperature and velocity was 1 000 K, 150 m/s, 400 K and 0.5 m/s, the test pieces with smaller angles and expansion sizes had less deposition on the tube wall, and the amount of deposition fluctuated with the increase of time during the initial stage of heating. The amount of deposition on the tube wall reached the maximum when heating for 15 minutes, and then the removal of a part of deposition caused the reduction of deposition measured. The influence of fuel nozzle and nozzle cap with different geometric structures on thermal protection characteristics was studied by means of numerical simulation and experiment. Results showed that the fuel nozzle with concentric arrangement of primary and secondary fuel passages had the best thermal protection effect, which could reduce the maximum wetted wall temperature by nearly 50% under test conditions, even better than the model with air gap. Reducing the contact area between the nozzle cap and the nozzle body or filling the materials with low thermal conductivity were effective improvement measures, which could reduce the outlet oil temperature by about 5 K. The results of this study have guiding significance for the design of fuel nozzle thermal protection.
作者
刘天池
范育新
吴伟秋
赵世龙
曾琦
LIU Tianchi;FAN Yuxin;WU Weiqiu;ZHAO Shilong;ZENG Qi(College of Energy and Power Engineering,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,China;Hunan Aviation Powerplant Research Institute,Aero Engine Corporation of China,Zhuzhou Hunan 412002,China)
出处
《航空动力学报》
EI
CAS
CSCD
北大核心
2020年第8期1628-1642,共15页
Journal of Aerospace Power
关键词
几何结构
结焦
燃油喷嘴
帽罩
燃油温升
热防护
geometric structure
deposition
fuel nozzle
nozzle cap
fuel temperature rise
thermal protection
