Experimental analysis on vibration characteristics of reduced scale gas transportation pipeline with liquid accumulation

Underwater compressed gas energy storage system (UWCGES) is a promising energy storage technology that can provide energy support for coastal cities, islands, and offshore infrastructures. However, in the process of gas transportation, the decreasing temperature in the marine environment leads to the generation of liquid water in the pipeline. Liquid accumulation in low-lying positions results in complex gas-liquid two-phase flow, causing pipeline vibration that affects flow. This coupling between the fluid and the pipeline will affect the normal operation of the whole system. In this study, an experiment of fluid-structure interaction induced pipeline vibration is conducted, and the results of simulation are verified by the experiment. The experimental and simulated results revealed an error margin of not exceeding 9.42%. Then, the pipeline vibration characteristics under the action of gas-liquid two-phase flow are analyzed by changing the gas flow rate and liquid accumulation. By 12 variable experiments, it can be observed that as gas flow rate and liquid accumulation volume increase, pipeline vibration frequency decreases, hence increasing the possibility of resonance occurrence. Furthermore, reducing gas flow rate and liquid accumulation volume can mitigate pipeline vibration, thereby augmenting the safe operation of energy storage pipelines.