燃烧条件下火焰筒温度及噪声载荷特性实验研究

Experimental Study on Surface Temperature and Acoustic Loads Characteristics of Flame Tube under Combustion Conditions

关键词:  航空发动机  火焰筒  结构强度  声载荷  温度场

Key words:  Aero engine  Flame tube  Structure strength  Acoustic load  Temperature field

摘要:

航空发动机燃烧室内部高温、气动及噪声等复杂载荷环境是导致火焰筒结构产生裂纹的主要因素之一，掌握火焰筒结构表面载荷特性及其与燃烧参数之间的关系，对于其强度评估非常重要。本文依据某型发动机真实构型设计了典型火焰筒试验件，搭建了模拟燃烧试验平台，发展了热电偶/示温漆组合测温和基于波导管的噪声测试方法，获得了不同燃烧状态下火焰筒表面的温度与噪声载荷分布特征，通过对比试验给出了进口温度、流量、供油量等参数对结构载荷的影响规律。结果表明，火焰筒表面噪声总声压级峰值超过150dB，总声压级、频率特性及分布特征与燃烧状态和结构振动特性等因素相关。

Abstract:

The complex load environments such as high temperature， aerodynamics， and acoustic inside the aero engine combustion chamber is one of the main factors that cause the flame tube structure to crack and fail. It is very important for strength evaluation to master the surface load characteristics of flame tube structure and its relationship with combustion parameters. Based on the ground combustion simulation test platform， a typical flame tube test piece was designed according to the actual configuration of an engine. The thermocouple/temperature indicating paint combined temperature measurement method and the acoustic measurement method based on waveguide were developed， and the temperature and acoustic load distribution characteristics of the flame tube surface under different combustion conditions were obtained. The influence of the combustion chamber inlet temperature， inlet flow rate， fuel supply and other parameters on the surface load of the flame tube were obtained by comparative experiments. The results show that the peak value of the total sound pressure level of the flame tube surface acoustic exceeds 150dB， and the total sound pressure level， frequency characteristics and distribution characteristics are strongly related to the combustion state and structural vibration characteristics.