串联型异形结构喷嘴冲击特性的实验研究

Experimental Research on Erosion Performances of Heterotypic Pulsed Jet Nozzle

针对普通喷嘴喷射效能不高的问题,比较不同结构参数下喷嘴产生自振脉冲射流效应的能力。基于喷嘴不同的结构参数和产生脉冲射流效应之间的关系,构建自振脉冲装置的物理模型,并对喷射能效进行实验分析。实验条件为:以靶盘为冲击对象,定量分析当量结构一致的球面、锥面和平面形冲击壁结构喷嘴的冲击压力,即腔长和靶距为自变量,射流冲击压力为因变量。实验结果显示:谐振腔长度对喷射效能的影响较大,锥面体冲击壁喷嘴随冲击能力最优,冲击效果好,平面体比球面体稍小;超过最佳腔长后,平面体喷嘴冲击压力增长速率明显降低。锥面体冲击壁喷嘴在其他自变量相同的条件下,其振腔内锥度为120°时的自激振荡脉冲效果最佳。实验结果充分验证了理论分析,这对喷嘴结构参数的设计和改进具有重要指导意义。

In view of the low injection efficiency of ordinary nozzles,the ability of nozzles to generate self-oscillating pulsed jet effects under different structural parameters was compared.Based on the relationship between different structural parameters of nozzles and the generation of pulsed jet effects,a physical model of a self-oscillating pulsed device was constructed.Experimental analysis was conducted on the jet energy efficiency.Taking the target disk as the impact object,the impact pressure of spherical,conical,and planar impact wall nozzles with the same equivalent structure was quantitatively analyzed.Cavity length and target distance were independent variables and peak and amplitude of jet impact pressure were dependent variables.The results show that the length of the resonant cavity has a significant impact on the injection efficiency.The conical organ tube has the best impact capacity against the wall nozzle,and the impact effect is good.The planar body is slightly smaller than the spherical body.After exceeding the optimal cavity length,the growth rate of impact pressure of the planar nozzle decreases significantly.Under the same conditions of other independent variables,the conical impact wall nozzle has a better self-excited oscillation pulse effect,and the 120°conical impact wall shape in its oscillation chamber is the optimal structure.The experimental results fully validate the theoretical analysis,which has important guiding significance for the design and improvement of nozzle structural parameters.