Analysis of In-Station Pressure Drops in Shale Gas Gathering Systems Using CFD and Network Modeling

This study investigates in-station pressure drop mechanisms in a shale gas gathering system, providing a quantitative basis for flow system optimization. Computational fluid dynamics (CFD) simulations, based on field-measured parameters related to a representative case (a shale gas platform located in Sichuan, China) are conducted to analyze the flow characteristics of specific fittings and manifolds, and to quantify fitting resistance coefficients and manifold inlet interference. The resulting coefficients are integrated into a full-station gathering network model in PipeSim, which, combined with production data, enables evaluation of pressure losses and identification of equivalent pipeline blockages. The results indicate that the resistance coefficients, valid only for fittings under the studied field-specific geometries, are 0.21 for 90° elbows in the fully open position, 0.16 for gate valve passages in the fully open position, and 2.3 for globe valve passages. Manifold interference decreases with lower high-pressure inlet values, whereas inlets farther from the high-pressure side experience stronger disturbances. Interestingly, significant discrepancies between simulated and measured pressure drops reveal partial blockages, corresponding to effective diameter reductions of 65 mm, 38 mm, 44 mm, 38 mm, and 28 mm for Wells 1#, 3#, 5#, and 6#, respectively.