The vortex motion causing edge tones
The vortex motion causing edge tones
复制标题
涡流运动导致边缘色调
DOI：
10.1088/0959-5309/49/5/306
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发表时间：
1937
期刊：
影响因子：
--
通讯作者：
G. B. Brown
中科院分区：
文献类型：
--
作者：
G. B. Brown
详细研究了当空气射流撞击边缘时所产生的音调，其速度从最低可能的速度延伸到孔中雷诺临界速度附近的速度。四个不同阶段的稳定涡的形成发生和整个现象被发现位于声敏感范围内的射流。在这个范围内，对于宽度为1毫米的缝和角为20°的楔，频率n与棱边距离h和平均速度U的关系可用公式n=0.466 j（U-40）（1/h-0.07）表示，其中四个阶段的j分别为1，2.3，3.8和5.4。由j=1表示的阶段可以与其他阶段同时发生，因此可以产生不同音高的两个音符。与敏感射流中的旋涡运动相比，显示出明显的相似性，但不能假定边缘音中的旋涡运动起源于孔口，因为在敏感射流中总是如此。
A detailed investigation has been made of the tones produced when a jet of air strikes an edge, with velocities extending from the lowest possible to those in the neighbourhood of the Reynolds critical velocity in the orifice. Four different stages of stable vortex-formation occurred and the whole phenomenon was found to lie within the sound-sensitive range of the jet. Throughout this range the dependence of the frequency n on the distance h of the edge and the mean velocity U can be closely represented for a 1-mm. slit-width and a wedge of angle 20° by the formula n=0.466 j (U-40) (1/h-0.07), where j=1, 2.3, 3.8 and 5.4 for the four stages respectively. The stage represented by j=1 may occur simultaneously with the other stages and thus two notes of different pitch may be produced. Comparison with the vortex motion in sensitive jets shows marked similarity, but it cannot be assumed that the vortex motion in edge tones has its origin at the orifice, as it always has in sensitive jets.