Discover the Editor's Choice: From each issue of the leading journal Water Science & Technology a member of the Editorial Board selects one outstanding paper to share across IWA Publishing platforms.  

IWA Publishing is pleased to announce that the 54th Editor's Choice Paper, chosen by the Editor-in-Chief, Wolfgang Rauch, is: 

Numerical study on effects of chamber design and multi-inlet on storm geyser

Jiachun Liu, Shuangqing Zhang, Biao Huang, David Z. Zhu

https://doi.org/10.2166/wst.2021.061

Why was this paper chosen?

We denote the eruption of air-water mixtures under high pressure conditions as a geyser event. Such incidents also occur in sewer system manholes under high transient flow conditions, i.e. in extreme storms. The event itself is potentially dangerous and the fast pressure changes accompanying the incident could damage the pipeline. While not a standard design issue for drainage engineers the phenomena is important and worthwhile to be investigated. Several authors have already resarched the problem of storm geyser events by means of 3-dimensional computational fluid dynamics (CFD) modeling and found the decisive factor being the trapping of air pockets. In this paper the authors follow this pathway and investigate several parameters for potential design improvement. The paper sets a good example to setup a CFD model by applying mesh independence tests, time step sensitivity analyses and validation. Following a detailed investigation of the phenomena the authors suggest a number of potential improvements such as trapping the air pocket upstream of the manhole in question or a deflector system in connection with air vents. I recommend this paper as an example of investigating specific hydraulic behavior with CFD – going a step beyond traditional sewer design.

Wolfgang Rauch, Editor-in-Chief.