典型损伤对复合材料机翼振动特性的影响

利用大型商用软件MSC.Patran建立了某型无人机复合材料机翼的有限元模型。在机翼中分别模拟了蒙皮分层、蒙皮与翼梁翼肋脱粘以及翼梁裂纹这3种典型损伤,通过与无损伤复合材料机翼固有振动频率进行比较,分析了损伤位置和大小对机翼振动特性的影响。结果表明:3种典型损伤一般不会引起机翼各阶振动模态的改变,但会使各阶振动频率发生变化;对各阶振动频率的影响既与损伤位置有关,也与主承力结构的损伤程度有关;蒙皮分层和翼梁裂纹出现在机翼根部时对机翼振动频率的影响最明显。

Influence of typical damages on composite wing vibration characteristics

Finite element model of composite wing on unmanned aerial vehicle of a particular type was established based on large-scale commercial software MSC.Patran. Three typical damages including skin delamination, debond between skin, beam and rib and crack on the beam were simulated in the wing. The effects of location and size of damage on vibration performance of wing were analyzed through comparing with the natural vibration frequency of undamaged wing. The results show that the three typical damages cannot induce the change of vibration modals of each order generally, but affect the vibration frequencies of each order. The effects on vibration frequencies of each order are not only concerned with the damage location, but also with the damage degree of major load-carrying structures. When skin delamination or crack on the beam appears in the root segment of the wing, the influence on the vibration frequency of wing is most obvious.