A Suggestion on the Mitigation Methods for Flow-Induced Vibration of a Coil Spring

Vibrational mechanisms of flow-induced vibration of a coil spring due to fluid flow were investigated and the mitigation methods were suggested. At first, as one of those vibrational behaviors, flow-induced vibration of a coil spring with a circular rod in the middle of it due to an axial flow was investigated experimentally using fundamental test apparatus. The effects of stiffness of springs, gap between springs and inner rod and initial compression of springs on the vibrational behavior were clarified, and a stability diagram is presented for the spring vibration. Based on the experimental results, the vibrational mechanisms of the coil spring with an inner rod were investigated. Finally, a design instruction on the mitigation of flow-induced vibration of coil springs including the cases of cross-flow-induced vibration and the axial-flow-induced vibration of a spring without an inner rod was summarized and suggested.