在改变伞衣面积和透气量的情况下,在定常风洞中对小型平面圆形伞的开伞过程进行了动态试验,研究了开伞过程中伞衣形状和伞衣所受载荷之间的动态关系.伞衣载荷不仅受降落伞阻力和附加质量变化率产生的力影响,同时,不稳定性及伞衣(绳)的抖动也是产生伞衣载荷的一个重要因素.稳定型伞衣充满后的载荷平均值约为最大开伞动载的60%左右,伞衣投影直径变化引起的呼吸现象也会引起载荷波动.透气量越大,降落伞稳定性越好,但降落伞的充气性能将会变差.该实验研究可为降落伞的载荷分析提供一定的依据.
The opening process of the circle flat parachute with the differential size and the differential vent position of the canopy by the steady flow wind tunnel were dynamic tested. The transient opening loads and the inflation shape of canopy were measured and the dynamic relation of them was gained. The results show that the transient opening loads are influenced not only by the aerodynamic forces of parachute, and the force produced by the change rate of added mass, but also by the instability and wave of canopy (or parachute suspension line). At mean time, the mean payload of canopy is nearly equal to 60% of the opening shock for the steady canopy. Besides, the load fluctuation is mostly produced by the " breath" phenomena. The bigger actual vent area of canopy, the better stability of a parachute, but the parachute inflation performance will worsen. The experiment investigation may be helpful for the further research.