Torsional vibration absorber using liquid

在旋转机械中，通常发现励磁扭矩发生在与转速相同的频率或转速的倍数处。非调谐减振器，如兰开斯特减振器，经常用来减少扭转振动。然而，它不像动力吸振器那样有效。如果所连接的动力吸振器具有与激励频率相同的固有频率，则振动被抑制。如果调谐得当，离心式摆式减振器可以有效地消除扭转振动。然而，由于摩擦或调节不充分，有时并不能令人满意地工作。本文对附加部分充满液体的中空圆柱体抑制转子扭转振动进行了实验和理论研究。中空圆柱体被径向壁分成相同的扇区。除了测量扭转振动外，还拍摄了表面波来观察所含液体的运动。测试的中空圆柱体的划分数为2、3、4、6和8。还研究了填充比的调整条件。实验结果表明，表面波向后运动，即沿与旋转方向相反的方向传播。给出了包括科里奥利加速度项在内的分析。分析结果与实验结果吻合较好，而不含科里奥利项的分析结果与实验结果吻合较差。因此，当液体运动时，由于科里奥利力的作用，表面波的运动不是平稳的。

In rotating machinery, it is generally found that exciting torque occurs at the same frequency as the rotating speed or at multiples of the rotating speed. An untuned vibration damper, such as the Lancaster damper.is frequently used to reduce torsional vibrations. However, it is not as effective as a dynamic absorber. If an attached dynamic absorber has the same natural frequency as the exciting frequency, vibration is suppressed. A centrifugal pendulum vibration absorber effectively eliminates torsional vibrations if it is well tuned. However, it sometimes does not operate satisfactorily due to friction or insufficient adjustment.An The experimental and theoretical study is performed on suppression of torsional vibrations of a rotor by attaching a hollow cylinder partially filled with liquid. The hollow cylinder is divided into identical sectors by radial walls. In addition to measuring torsional vibration, surface waves were photographed to observe the motion of the contained liquid. The number of divisions of tested hollow cylinders is 2,3,4,6, and 8. The tuning conditions for fill ratios are also examined. Experimental results show that the surface waves move backward that is travel in the direction opposite the rotation. Analysis including the Coriolis acceleration terms is presented. Analytical results show good agreement with the experimental ones whereas the analysis without Coriolis terms shows poor agreement. Accordingly the surface wave motion is not stationary due to the Coriolis force which acts while the liquid moves.