The tangential velocity distribution measured in this study is similar to a vortex core existing along the jet axis.

旋转射流的切向速度分布相当于射流中存在一个旋转的涡核。

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Vortex also called left turn, is the axis of rotation happened a self-excited vibration, it is neither has the free vibration characteristics, also do not belong to the type of forced vibration.

涡动又称甩转，是旋转轴发生的一种自激振动，它既不具有自由振动的特征，也不属受迫振动的类型。

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