Fast and reliable transient simulation and continuous optimization of large-scale gas networks

We are concerned with the simulation and optimization of large-scale gas pipeline systems in an error-controlled environment. The gas flow dynamics is locally approximated by sufficiently accurate physical models taken from a hierarchy of decreasing complexity and varying over time. Feasible work regions of compressor stations consisting of several turbo compressors are included by semiconvex approximations of aggregated characteristic fields. A discrete adjoint approach within a first-discretize-then-optimize strategy is proposed and a sequential quadratic programming with an active set strategy is applied to solve the nonlinear constrained optimization problems resulting from a validation of nominations. The method proposed here accelerates the computation of near-term forecasts of sudden changes in the gas management and allows for an economic control of intra-day gas flow schedules in large networks. Case studies for real gas pipeline systems show the remarkable performance of the new method.

TWO DIAMETERS METHOD FOR BINDING SITES IN HYDRAULIC CALCULATION OF PIPELINE SYSTEMS

The article is devoted to solving the urgent problem of increasing the efficiency of linking sections in the hydraulic calculation of pipeline systems to reduce the material and energy consumption of the system as a whole. The aim of the work is to create an effective method of hydraulic linking of sections of pipelines of microclimate support systems, namely the "two-diameter method" and the establishment of analytical calculations, provided that a meager percentage of the inconsistency of parallel sections. Graphical and analytical dependences on basis of conducted theoretical calculations are presented. Analytical calculation dependences have been established under the condition of achieving a negligible percentage of in consistency of parallel sections. An effective method of hydraulic and aerodynamic linking of parallel sections of pipeline systems has been developed, namely the "two-diameter method".