高扰动燃油喷嘴雾化试验

为改善航空发动机的燃油雾化、验证高扰动雾化方案应用于航空发动机燃油喷射的可行性,采用相位多普勒粒子分析仪(PDPA)及高速摄影技术,对不同夹角、不同孔径结构条件下的V形交叉孔高扰动喷嘴和单孔喷嘴的喷雾场粒子特性进行了测量。结果表明:随着供油压差增大,雾化锥角随之增大,索太尔平均直径(SMD)值随之减小;交叉孔结构对燃油雾化有明显促进作用,在相同的供油压差、出口截面积条件下,交叉孔的雾化锥角更大,SMD更小;在SMD相同时,交叉孔所需的喷射压力远小于圆直孔;随着交叉角的增加,雾化锥角、SMD均有明显改善;采用空气辅助能够有效增大雾化锥角、降低SMD值,但改善效果随气压增加而逐渐减弱。与传统单孔喷孔方案相比,高扰动喷孔能够在相同压力条件下极大的改善燃油雾化效果。 

Experiment on atomization of high disturbance fuel nozzle

In order to improve the fuel atomization and verify the feasibility of high perturbed atomization scheme applied to the fuel injection of aero-engine, the spray characteristics of V-shaped cross hole nozzlesand single hole nozzles were measured by using phase Doppler particle analyzer (PDPA) and high-speed photography technology. Results showed that with the increase of injection pressure, the atomization angle increased and the Sauter mean diameter(SMD) value decreased. The cross-hole structure had a significant promoting effect on fuel atomization. Under the same injection pressure and exit cross-section area conditions, the atomization cone angle of the cross-hole was larger and the SMD was smaller; at the same SMD, the required injection pressure of the cross-hole was much smaller than that of the traditional circular straight hole; with the increase of intersection angle, the spray cone angle and SMD were both improved. Air-assisted method can effectively increase the spray cone angle and reduce the SMD value, but the improvement effect decreased gradually with the increase of air pressure. Compared with the traditional single hole nozzle scheme, the high perturbation nozzle can greatly improve the atomization effect of the fuel under the same pressure conditions, and has great potential for aero engine application.