Research on thermal insulation performance of composite energy storage pipeline with phase change materials

The oil and gas pipeline transportation technology is the key to the surface production of oil field, and the pipeline insulation technology plays an important role in realizing the safe, stable and energy-saving transportation of crude oil. The composite energy storage pipeline with PCM not only has thermal insulation performance, but also can greatly prolong the safe shutdown time when the shutdown condition occurs by taking advantage of the storage and discharge energy characteristics of PCM. In this paper, the reasonable structural parameters of composite energy storage pipeline with PCM were determined by comparing the effective insulation time of three typical pipelines under the same working conditions and combining with thermal resistance method. Considering the nonlinear latent heat release and phase change characteristics of crude oil, a pipe-PCM-oil coupling thermodynamic model was established for the composite insulation pipeline, and numerical solution was carried out. The heat transfer characteristics of composite energy storage pipeline with PCM under different working conditions were analyzed, and the effects of physical properties and structures of different PCM on the thermal insulation performance of composite energy storage pipeline were compared. The research results can provide theoretical support for the safe shutdown scheme of oil pipeline. • The nonlinear release of latent heat of crude oil, the mathematical model of pipe-PCM-oil multi-field coupling heat transfer was established.