Abstract: | An applied fluid-dynamics model of the non-stationary flow in a long multilayer-insulated high-pressure 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. The applied model allows one to significantly increase the speed of numerical computation of the fluid-dynamics parameters of the gas flow in the pipeline, which is necessary for multivariate computations in design and operation of gas pipelines. |