双S弯二元排气系统遮挡偏距比对壁温与红外辐射影响的试验研究  

Experimental Investigation of Infrared Signatures of Serpentine 2-D Nozzle Exhaust System with Different Shield Ratios

作　　者：杨坤 于明飞 杜凯 霍旭东 YANG Kun;YU Mingfei;DU Kai;HUO Xudong(Guizhou Aero Engine Research Institute,Aero Engine Corporation of China,Guiyang 550081,China;College of Energy and Power Engineering,Nanjing University of Aeronautics&Astronautics,Nanjing 210016,China)

机构地区：[1]中国航发贵阳发动机设计研究所,贵阳550081 [2]南京航空航天大学能源与动力学院,南京210016

出　　处：《南京航空航天大学学报》2023年第4期606-613,共8页Journal of Nanjing University of Aeronautics & Astronautics

摘　　要：为了探究不同遮挡偏距比双S弯排气系统的红外特性,试验研究了遮挡偏距比为55%和100%的双S弯二元排气系统的壁面温度分布和红外辐射特性,并与相应的基准轴对称排气系统进行了对比分析。结果表明:S弯喷管壁温整体要比基准轴对称喷管高约25%,第一S弯下游的上壁面附近存在局部高温区,提高S弯喷管遮挡偏距比后,温度梯度加剧,热应力集中。与基准轴对称排气系统相比,55%和100%遮挡偏距比双S弯二元排气系统均具有突出的红外抑制效果,正尾向(α=0°)红外辐射强度分别降低77.7%和79.3%。从温度和红外辐射强度综合评价,遮挡偏距比并非全遮挡最好,遮挡偏距比从55%提高到100%后,仅能有效抑制上方探测面α=5°和10°的红外辐射,而基本不会改变尾向其他探测方向的红外辐射,在工程设计时应权衡优化损失。To explore the infrared radiation characteristics of double serpentine 2-D exhaust system with different blocking rates,the wall temperature distribution and infrared radiation characteristics of serpentine 2-D exhaust system with shield ratios of 55%and 100%are experimentally studied and compared with the corresponding reference axisymmetric exhaust system.The results show that the overall temperature of the serpentine nozzle wall is about 25%higher than that of the reference axisymmetric nozzle,and there is a local high temperature area near the upper wall downstream of the first turning.After increasing the shield ratio of the serpentine nozzle,the temperature gradient intensifies and the heat stress concentration.Compared with the reference axisymmetric nozzle,the serpentine 2-D exhaust system with 55%and 100%shield ratios has outstanding infrared suspension effect,and the rear(α=0°)infrared radiation intensity is reduced by 77.7%and 79.3%,respectively.From the comprehensive evaluation of temperature and infrared radiation intensity,the shield ratio is not the best for full occlusion.After the shield ratio is increased from 55%to 100%,it can only effectively suppress the infrared radiation of the upper detection surfaceα=5°and 10°,and hardly change the other backwards.The infrared radiation in the detection direction should be weighed and optimized during.

关 键 词：涡扇发动机排气系统 双S弯二元喷管 遮挡偏距比 红外抑制 

分 类 号：V231[航空宇航科学与技术—航空宇航推进理论与工程]