固体火箭发动机喷焰瞬态特性实验

Experimental study on transient characteristics of solid rocket motor exhaust plume

以固体火箭发动机系留实验采集图像数据为基础,采用图像均值与方差分析、喷焰典型位置亮度时间序列的快速傅里叶变换(FFT)、改进Hilbert-Huang变换(改进HHT)等方法对其瞬态特性进行分析处理。分析结果表明:在获取的频带内,喷焰整体不存在明显的主脉动频率,各个频率上均存在较小的脉动分量,且核心区的脉动幅值要小于湍流混合区,同时湍流混合区的脉动与核心区的脉动之间存在相关性,基于改进的自适应噪声完备集合经验模态分解算法(ICEEMDAN)的改进HHT变换可作为分析固体火箭发动机喷焰等非平稳信号瞬态特征变化机理的有效手段。

Based on the image data collected from the solid rocket motor mooring experiment,the image mean and variance analysis,the fast Fourier transform(FFT)of the time series of the brightness of the typical position of the flame,and the improved Hilbert-Huang transform(improved HHT)were used to analyze the data.Transient characteristics were analyzed and processed.The analysis results showed that:in the obtained frequency band,there was no obvious main pulsation frequency in the entire exhaust plume,and there were small pulsation components at each frequency,and the pulsation amplitude in the core area was smaller than that in the turbulent mixing zone.There was a correlation between the pulsations in the core region and that in the turbulent mixing zone,and the improved HHT based on the improved adaptive noise complete set empirical mode decomposition algorithm(ICEEMDAN)can be used as an effective means to analyze the transient characteristic change mechanism of non-stationary signals such as solid rocket engine flames.