运载火箭起飞噪声环境缩比模型试验方法

基于相似理论建立缩比模型试验相似准则，提出了火箭发动机喷流声场试验预示方法的流程。通过缩比模型系留点火试验，根据几何相似、喷流参数相似、发射环境相似来预示起飞噪声环境，在国内首次给出了运载火箭表面的噪声环境的空间相关特性，结果表明预测结果与遥测数据之差小于1.5 dB，校验了缩比模型方法的有效性。缩比模型方法对于我国新一代运载火箭的起飞噪声环境预示、噪声载荷设计、地面试验具有重要意义。

The Lift off Acoustic Prediction Methods with Scale Model Acoustic Test of Launch Vehicle

Based on similarity theory the similarity criteria of scaled model acoustic field test are established and the prediction process for jet noise test of rocket engine is proposed. Through the scaled rocket model mooring ignition test, the lift-off acoustic environment is predicted according to similar geometry, jet flow parameters and launch environment. Then the spatial correlation characteristic of acoustic environment on launch vehicle surface is given. It is found from comparison that the error between prediction result and telemetry data is below 1.5 dB, and the validity of the proposed method is demonstrated. The scaled model method is of great significance for lift-off acoustic environment prediction, acoustic load design and ground test of Chinese new generation launch vehicle.