Economic and Hydraulic Co-Optimization Model and Solution Strategy for Star-Star Networks Design Considering Facility Location and Capacity Configuration

Summary When optimizing the design of an oil-gasfield gathering and transferring pipeline network (OGF-GTPN), ensuring investment benefits and meeting practical requirements are key factors for achieving outstanding design results. There is a scarcity of research on the simultaneous optimization of multiple factors such as topology, facility processing capacity, pipeline size, or pressure characteristics. Therefore, this paper comprehensively considers the structure parameters and operational requirements of the network, constructing a star-star layout, capacity setting, and hydraulic parameter optimization model (SSLCHP-OM). Capable of globally optimizing the station location, capacity configuration, and hydraulic parameters of the star-star layout, the model is solved using nonlinear processing and the branch-and-bound (BB) method to determine key variables such as pipeline connections, pipeline sizes, station types, station locations, and central treatment plant (CTP) location. Compared with previous studies, this achieves the minimization of investment for the star-star OGF-GTPN while meeting transportation requirements. By solving the case, sensitivity analyses are conducted on eight scenarios with station types, hydraulic boundaries, and piecewise linearization intervals. The research findings reveal that different station types (Scenario II, III, and IV) result in varying station counts after optimization, leading to differences in pipeline size, length, investment, and pressure drop. Compared with Scenarios III and IV, Scenario II has no increase and an increase of 1 station, respectively, with the total investment reduced by 1.042 × 10⁷ Yuan and 4.79 × 10⁶ Yuan. Different hydraulic boundaries (Scenarios V and VI) also have impacts on pipeline size, pressure drop, and investment, with the total investment of Scenarios V and VI increased by 3.7 × 105 Yuan and 4.5 × 105 Yuan, respectively, compared with Scenario I. Relative to Scenario I, changes in linearization intervals (Scenarios VII and VIII) lead to alterations in solution accuracy and solution time. In Scenario VIII, the average relative errors of the pipeline’s starting and end pressures are reduced by 0.09% and 0.58%, respectively, while the solution time increases by 88.51%. This research provides certain guiding significance for the design optimization of star-star OGF-GTPN.