Author(s): Shuai Zhang; Yiran Wang; Adrian Wing-Keung Law
Linked Author(s): Wing Keung, Adrian Law
Keywords: Scroll vortex drop shaft large eddy simulation transient flow characteristics air core percentage
Abstract: Drop shafts perform the critical role to convey surface flows downward to pipes or tunnels deep underground, and their efficiency is critical to ensuring urban resilience against flooding. This numerical study employs Large Eddy Simulations (LES) to investigate transient flow dynamics within a drop shaft equipped with a scroll vortex intake. First, the LES predictions are validated against experimental data from Guo (2012), demonstrating good agreement for both the time-averaged head-discharge relationship and minimum air core percentage. Subsequently, we examine the transient fluctuations of the air core, and the results show up to 13% variation in the non-dimensional air core area due to dynamic contraction and expansion. The overall findings underscore the need to consider the turbulent fluctuations in future design standards and considerations.
Year: 2025