Vibration Control of a Pipeline Structure Using Pounding Tuned Mass Damper

Pipeline structures are often very flexible and susceptible to vibrations induced by many sources, such as vortex, external flow, and internal fluid flow. The pounding tuned mass damper (PTMD) is one device that may be employed to absorb and dissipate these undesired vibrations. The PTMD is a combination of the tuned mass damper and the impact damper. It utilizes the tuned mass to absorb kinetic energy and dissipates the absorbed energy through collisions. To examine the vibration control effectiveness of the PTMD, both numerical analysis and experimental study were performed. In the numerical analysis, a pounding force model was established based on the Hertz contact element. The motion equation of a pipeline structure incorporated with a PTMD was derived. Free vibration analysis and forced vibration analysis were performed. In the experimental study, an M-shaped pipeline was fabricated and installed with the PTMD. Due to safety issues the pipe was kept empty during the experiments. A free vibration experiment was first executed with and without PTMD to determine its effectiveness. Experimental data showed that the damping ratio of the pipeline structure was effectively increased when the PTMD was installed. Then the pipeline was subjected to harmonic excitation to attain resonance. Experimental results also showed that the PTMD effectively reduced the vibration of the pipeline structure.