导流槽和混合比对发动机喷流噪声特性影响实验研究

摘要

To investigate the characteristic of jet noise for rocket engine, design a experimental rocket engine to produce supersonic jet. The jet noise is measured by the BK data acquisition system and analyzed by the noise processing software. The impact of mixture ratio for rocket engine and distance from nozzle exit to flame deflector on the jet noise is analyzed. As the experimental result shows, the sound pressure level of jet noise declined with the increase ofmixture ratio, and the working condition of rocket engine has changed from Fuel-rich combustion to Oxygen-rich combustion. The flame deflector has shadowing effect on jet noise. With the increase of distance from nozzle exit to flame deflector, the shadowing effect trailed off and the sound pressure level reduced.%为分析研究火箭发动机喷流噪声特性的影响因素,设计了火箭发动机喷流噪声实验系统;采用BK数据采集系统及噪声处理软件进行噪声数据的采集和分析,研究发动机混合比以及导流槽对火箭发动机喷流噪声特性的影响.结果表明:随着发动机混合比的上升,发动机从富燃燃烧状态转换到富氧燃烧状态,噪声声压级降低;导流槽对喷流噪声有遮蔽作用,且随着导流槽距喷管出口距离的增大,遮蔽作用下降,噪声声压级上升.