为有效控制折板型竖井在高压截留气团释放过程中产生气爆的强度,采用FLUENT软件,基于Realizable k-ε湍流模型和VOF两相流模型构建了折板型竖井气爆三维数值模型,对不同联络管接入方式、干/湿区连通区域、限流孔板及通气管的气爆喷射过程进行三维模拟。研究结果表明:相比于竖井干区,联络管接入湿区时能够降低折板水力冲击荷载,并且对折板结构安全有利;干/湿区连通区域面积大小对气爆控制效果具有两面性;在竖井干区中部设置一限流孔板,同时在远离竖井一端的联络管正上方设置一通气管,能够有效控制气爆强度。研究成果可为折板型竖井结构设计及安全运行提供理论参考。

[Objective] This study aims to systematically investigate the control measures for geyser intensity in baffle-drop shafts during the release of high-pressure trapped air pockets. By analyzing the effects of key parameters—including the connection mode of the communication pipe, the area of the connecting region between dry and wet zones, the position and open area of the throttling orifice plate, and the installation distance of the vent pipe—on the geyser height and the impact load on baffles, a set of comprehensive optimization measures balancing geyser control effectiveness and structural safety is proposed. [Methods] FLUENT software was used to establish a three-dimensional numerical model of geyser in a baffle-drop shaft based on the Realizable k-ε turbulence model and the VOF two-phase flow model. The Dongfeng Road baffle-drop shaft of the Donghao Chong deep tunnel project in Guangzhou was selected as the research object. The effects of different communication pipe connection modes (dry zone/wet zone), areas of the connecting region between dry and wet zones, throttling orifice plate parameters (height and open area), and vent pipe installation distance on the jet height of geysers and the impact load on baffles were systematically simulated. A total of 88 working conditions were simulated, and model reliability and computational accuracy were ensured through grid independence verification and comparison with experimental data. The response patterns of geyser intensity and baffle impact load to each parameter were analyzed in detail. [Results] Although connecting the communication pipe to the wet zone had a limited effect on the geyser height, it significantly reduced the impact load on the baffles—particularly on the bottom baffle, where the peak load was reduced by up to 66%. The area of the connecting region between the dry and wet zones showed a nonlinear relationship with the baffle load; as the area decreased, the impact load on the bottom baffle increased markedly. The optimal control effect was achieved when the dimensionless area S^*=0.318. When the throttling orifice plate was positioned at the mid-height of the dry zone (1/2H) with an open area of ϕ^*=0.058, the maximum geyser height decreased by approximately 70%, while the impact load on the baffles dropped by more than 30%. The best control effect was achieved when the vent pipe was positioned at the end of the communication pipe farthest from the shaft (δ^*=4D), and no water-air mixture overflow occurred. [Conclusion] Considering the combined influence of these factors on the geyser intensity in the shaft, a joint control measure—“wet-zone connection + mid-position throttling orifice plate + remote vent pipe + optimized connecting area layout”—was proposed. Under typical working conditions, this combined approach reduced the geyser height by up to 80% and the average impact load on the baffles by more than 50%, effectively controlling the geyser intensity while ensuring the structural safety of the shaft. It provides reliable theoretical support and practical guidance for the safe design and operation of baffle-drop shafts in deep tunnel drainage systems and offers a replicable and scalable technical approach for future geyser risk prevention and control in deep tunnel systems.