Experimental Study of the Air Demand of a Spillway Tunnel with Multiple Air Vents
Source abstract
Abstract
Accurate prediction of air demand in free-surface flows through high-head spillway tunnels with multiple vents represents a critical design challenge. Existing empirical formulas for estimating air demand, derived from studies of single vents using experimental and prototype data, are not directly applicable to multi-vent configurations. This study investigates the combined effects of key parameters on ventilation requirements: (1) flow characteristics (velocity range of 6–12 m/s and depth varying between 0.06 and 0.1 m); (2) vent geometry (total vent area from 28 to 140 cm2 and spatial distribution). Through an experimental analysis, an empirical formula is derived to correlate wall roughness with interfacial shear stress, enabling an improved method for estimating air demand in spillway tunnels with multiple air vents. The resulting predictive model achieves ±25% agreement with two prototype case studies and model tests. These experimentally validated relationships provide quantitative guidelines for optimizing ventilation system designs.
Source: crossref · Quality: baseline
Research context
OpenAlex topics: Hydraulic flow and structures · Water Systems and Optimization · Hydraulic and Pneumatic Systems
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
State Key Laboratory of Hydraulics and Mountain River Engineering, Chengdu 610065, China
Funding
National Natural Science Foundation of China
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