@article{Du2026, 
author = {Yunchao Du and Xianming Shi and Zhiqiang Liu and Jian Wu},
title = {Perforated Partition Walls in Extra-Long Tunnels: A One-Dimensional Flow Model Based on Orifice Theory},
year = {2026},
journal = {Fluid Dynamics & Materials Processing},
volume = {22},
number = {4},
pages = {6},
keywords = {High-speed train, extra-long tunnel, perforated partition wall, pressure fluctuations, one-dimensional flow model},
url = {https://www.sciopen.com/article/10.32604/fdmp.2026.080083},
doi = {10.32604/fdmp.2026.080083},
abstract = {Perforated partition walls are widely employed in complex underground transportation systems to mitigate tunnel pressure waves, harness train-induced piston wind for reduced ventilation energy consumption, and support emergency operations. Building on orifice flow theory, this study develops a one-dimensional flow model for tunnels equipped with perforated partition walls. The model is applied to examine the aerodynamic performance of such walls in extra-long tunnels through a comprehensive parametric analysis, considering the presence of openings, opening ratio, spacing, and spatial arrangement. The results demonstrate that, for opening ratios, defined as the ratio of the perimeter of a single opening to the wetted perimeter of the tunnel on the train-passing side, ranging from 0 to 0.32, the model accurately captures train-induced pressure fluctuations. The introduction of a perforated partition wall reduces the overall amplitude of pressure fluctuations by 41.7% compared with the non-perforated configuration. Specifically, pressure peaks outside the leading and trailing cars decrease by 41.4% and 28.5%, respectively. Increasing the opening area enhances cross-wall airflow and effectively attenuates pressure fluctuations on the train-passing side, while reducing opening spacing further intensifies this effect. For a fixed number and ratio of openings, a uniformly distributed arrangement along the entire wall produces smoother pressure variations than configurations concentrated near the center or ends. An optimal design is identified, consisting of a uniform opening distribution with an opening ratio of 0.20 and a spacing of 10 m.}
}