突扩区/火焰筒头部流动特性研究

本文试验研究某型直流短环燃烧室突扩区／火焰筒头部流动特性，测量突扩区，火焰筒内外环气流通道及整个燃烧室的总压损失和燃烧室各股气流通道的分流比，采用ＬＤＶ多谱勒激光测速仪测量突扩区流场。通过对二种燃烧室和七种不同结构方案的突扩扩压器流场测定，综合分析突扩扩压器主要几何参数对流场参数，总压损失及分流比等燃烧室性能参数影响规律，为燃烧室的研制和改进设计提供有用的试验依据。

AERODYNAMIC CHARACTERISTICS OF HEAD IN SECTOR ANNULAR COMBUSTOR

The aerodynamic characteristics of sudden expansion region between the prediffuser exit and the head of the flametube in relation to its geometric parameters are investigated with the purpose of the annular combustor optimization.The mass flow ratio,total pressure loss of outer and inner annulus,and whole combustor are measured with different total pressure probes and flowmeters,respectively.Flow velocity profiles in the asymmetric sudden expansion region are measured by Laser Doppler anemometry.Experemental results of flow field total pressure loss and flow ratio for two types of combustor and seven configuration sectors show that two eddies occur in the sudden expansion regions;the prediffuser geometric parameters,such as deflection angle;relative sudden gap L/h and inlet Mach number,have an effect on the airflow patterns,drag coefficient and mass flow ratio.