Computer modelling of the long multilayer-insulated high-hressure subsea gas pipeline

For the non-stationary gas flow in a long multilayer-insulated high-pressure subsea gas pipeline, an computer model was developed that takes into account transient heat-transfer processes in the long multilayer wall of the pipeline. These processes may influence the energy balance of the flowing gas. The numerical algorithm of the joint decision of system of the equations of gas dynamics and the heat conduction equation in a multilayered wall of the pipeline is presented. The adequacy of the model was checked on an industrial subsea pipeline more than 300 km long. An applied fluid-dynamics model of the non-stationary flow in a long multilayer-insulated highpressure subsea gas pipeline was developed. Instead of a complex partial differential heat conduction equation, which represents the heat flux between the flowing gas and the environment in the energy balance equation, the model uses a first-order ordinary differential equation. Results of computing experiments on check of adequacy of applied model are resulted.