Application of the Pounding Tuned Mass Damper to a Submerged Jumper Experiencing Horizontal and Vertical Vibrations

Jumper pipelines are crucial for hydrocarbon exploration. In offshore environment these jumpers are exposed to vibration inducing environments, such as external flow (vortex) around pipe and internal flow through a pipe. These flows excite the various vibration modes in jumpers. These vibrations cause additional stress on the jumper joint and adversely affect the fatigue life of jumpers. This paper presents research on the pounding tuned mass damper (PTMD) applied to a subsea jumper for passive vibration suppression. A preliminary finite element based analysis is performed to understand the behavior of the PTMD on a mock up jumper, both in air and underwater. A key component of the modeling is to understand the modal behavior of the jumper for development of the PTMD. During the initial phase, effectiveness of the PTMD damper on vibration attenuation of the jumper in air is evaluated with free vibration testing and resonant vibration testing. For the second phase, the test setup was submerged underwater. Test results show that the PTMD is more effective at suppressing the first mode (vertical) than the later modes. Results also indicate that the PTMD successfully dampens jumper vibrations under submerged conditions to a satisfactory level. The observed reduction in vibration amplitude can help to reduce fatigue damage to jumpers, increasing their life span considerably. This makes the PTMD a desired solution for vortex induced and flow induced vibration suppression for deep sea applications.