高速高温空气横向射流条件下直射式喷嘴 燃油轨迹研究

为了优化冲压发动机燃油系统的设计,对高速高温空气来流横向射流条件下直射式喷嘴燃油轨迹进行试验研究和理论分析,试验采用PIV拍摄油雾场,经过Matlab图像处理后获取穿透边界,获得不同空气来流压力(0.17~0.28 MPa)、来流温度(400~750 K)、来流速度(43.641~109.420 m/s)、喷孔直径(0.77~1.00 mm)、燃油压力(1.2~2.7 MPa)下燃油轨迹的变化规律。结果表明:空气来流参数中的温度、压力以及喷油参数中的喷孔直径、燃油压力等对穿透深度均有影响。在试验范围内,随着空气温度或压力增加,燃油穿透深度减小;随着喷油孔径或喷油压力增加,燃油穿透深度增加。通过对燃油粒子和空气来流动量比关系的分析,获得用于预测燃油轨迹的无量纲关系式。

Study on the Fuel Trajectory of Direct Jet under High-speed and High-temperature Transverse Jet

In order to optimize the design of ramjet fuel system,the fuel trajectory of direct jet under high-speed and high-temperature transverse jet was studied and analyzed.The oil fog field was photographed by PIV,and the penetration boundary was obtained after Matlab image processing.The variation of fuel trajectory was obtained under different air inflow pressure(0.17~0.28 MPa),inflow temperature(400~750 K),inflow velocity(43.641~109.420 m/s)and injection hole diameter(0.77~1.00 mm),fuel pressure(1.2~2.7 MPa).The results show that the temperature and pressure of the air inflow,the injection aperture and the fuel pressure all have effects on the penetration depth.In the test range,the penetration depth of fuel decreases with the increase of air temperature or pressure.The fuel penetration depth increases with the increase of the injection aperture or injection pressure.The dimensionless relation for predicting the fuel trajectory is obtained by analyzing the flow ratio of the fuel particles and the air flow.