直升机排气系统红外抑制器的模型实验研究  

MODEL EXPERIMENTS OF INFRARED SUPPRESSOR FOR HELICOPTER EXHAUST SYSTEM

作　　者：张靖周[1] 李立国[1] 高潮[1] 

机构地区：[1]南京航空航天大学能源与动力学院,江苏南京210016

出　　处：《红外与毫米波学报》2005年第2期125-129,共5页Journal of Infrared and Millimeter Waves

基　　金：武器装备预研基金(51410040304HK0201)资助项目

摘　　要：对直升机排气系统红外抑制器进行了一系列的模型试验研究,旨在分析引射混合和遮挡隔热对降低目标红外辐射特征的作用机制和抑制效果,并对缩比模型的红外辐射相似关系进行探讨.结果表明: (1)引射冷气掺混具有降低排气温度和混合管壁面温度的双重作用,其降温效果在大引射流量比下非常显著;当遮挡间距大于 20mm,遮挡隔热可以使遮挡罩壁温接近于环境温度. (2)引射混合对总体红外辐射强度抑制约 85%;在此基础上进行隔热遮挡可以再抑制 10%. (3)在保持主流速度、温度和压力均相同的条件下,不同缩比模型的辐射亮度基本相当;红外辐射强度基本上与模型的几何模化比平方成正比.A series of mode experiments for the infrared signature suppression (IRSS) device used in the helicopter gas turbine exhaust system were carried out to investigate the effects of ambient air pumping-mixing and heat shelter-insulation on decreasing the target infrared signature and quest for the infrared signature similarity between two scaled models with different scale factors. The results show that (1) Ambient air pumping-mixing plays a dual role for reducing the exhaust temperature and mixing duct temperature and this role is more obvious in the case of larger mass flow ratio of secondary flow to primary flow. Sheltering from the hot mixing duct wall makes the sheltering sheath temperature close to ambient temperature in case of the sheltering distance greater than 20mm. (2) Ambient air pumping-mixing contributes about 85% suppression for the total target infrared radiation intensity and heat shelter-insulation contributes about 10% suppression again. (3) While the primary flow velocity, temperature and pressure are at the same condition for different scaled models, the irradiances for different scaled models are almost the same and the infrared radiation intensity is almost proportion to the square of model scale factor.

关 键 词：红外抑制器 排气系统 直升机 实验研究 红外辐射强度 红外辐射特征 缩比模型 试验研究 抑制效果 作用机制 双重作用 壁面温度 排气温度 冷气掺混 相似关系 降温效果 环境温度 主流速度 辐射亮度 遮挡 引射 隔热 混合管 流量比 

分 类 号：V218[航空宇航科学与技术—航空宇航推进理论与工程] U464.134.4[机械工程—车辆工程]