通过有限元分析与动力学试验相结合的方法对馈源喇叭结构动力学特性进行了研究。根据车载雷达馈源结构,以 馈源安装点实测的加速度功率谱密度为激励对3种馈源喇叭进行了振动试验;同时,分别建立了有限元动力学计算模型 并进行随机振动分析,得出基频以及y向加速度均方根值偏差在8. 5%以内。在有限元模型验证的基础上,对3种构型馈 源喇叭振动环境下的应力响应进行比较分析。计算结果表明:打弯槽中φ0. 8铜丝对打弯槽焊缝强度加强明显,局部最大 应力降低了52% ;加强筋降低馈源喇叭上加速度响应约20% ,对喇叭根部应力改变明显,从而对馈源喇叭结构设计提供 了参考依据。

Dynamic characteristic of the feed horn has been studied by finite element method and the dynamics test. Three kinds of feed horns as the substructure of armored vehicle radar are chosen for vibration experiment. The power spectrum density of acceleration on the feed fixing point is selected as vibration input condition for the experiment. Meanwhile, a dynamic finite element model is established and random vibration analysis has been taken. The difference of fundamental frequency and acceleration RMS in the y direction is in order of 8. 5% base on the dynamic model validation, the local maximum stress response reduces 52% due to the reinforcement of ψ0. 8 copper wires and feed horn acceleration response decreases 20% due to the reinforced ribs. This conclusion is very valuable for the design of feed horn.