Review of Computational Fluid Dynamics: Applications in Water, Wastewater, and Stormwater Treatment edited by Xiaofeng Liu and Jie Zhang

This book, prepared by the Environmental and Water Resources Institute (EWRI) of the ASCE Computational Fluid Dynamics (CFD) Task Committee, deals with CFD and its applications in water, wastewater, and stormwater treatment, and is more than 200 pages. To the authors’ knowledge, no other textbook provides similar coverage of this subject area. Only a few open channel hydraulics textbooks include introductory sections on CFD (Sturm 2010). This new book attempts to address this void. Furthermore, the number of presented case studies is quite impressive and makes this book a valuable reference.

CFD is a computer simulation technique for predicting fluid flow, heat and mass transfer, chemical reactions, and related phenomena by solving a set of numerical governing mathematical equations including conservation of mass, conservation of momentum, and conservation of energy.

The book contains 23 chapters organized into five parts, each written by different EWRI CFD committee members. The five parts are as follows:

While each part is well organized, the overall organization of the book is somewhat disappointing. For example, the introduction of CFD fundamentals and concepts is not presented until Part 2.

The application examples in this book use a mix of open-source and commercial software. Additionally, one of the editors states that Supplemental Data for the text are available for downloading (Liu 2019).

Part 1 starts with the physical, chemical, and biological processes occurring in most treatment facilities. Part 2 gives an overview of CFD, turbulence-resolving methodologies and turbulence modeling, pre- and postprocessing, verification and validation, and available packages and codes.

Part 3 describes the water treatment technologies and CFD application case studies covering different water treatment processes (aeration, sedimentation, ozone disinfection, pumping, and flow distribution). These processes may also be used in wastewater and stormwater treatment. Although the book covered pump intake design in this part (Chapter 12), it does not provide a discussion on turbulence closure models used in the presented case studies. This is unfortunate given how the choice of the turbulence closure model impacts the accuracy of the prediction of vortex formation (locations and intensities), as well as that of the swirling flow in the intake pipe (Constantinescu and Patel 2000).

Parts 4 and 5 describe wastewater [typical processes including sludge tanks, water stabilization ponds, algae ponds, and ultraviolet (UV) disinfection] and stormwater treatment technologies along with CFD application case studies. CFD applications in stormwater collection, filtration, and separation are fully discussed in Part 5.

The book lacks coverage of CFD simulations in open channel flows and for flows through in-stream hydraulic structures such as spillways, culverts, and weirs. Unfortunately, CFD techniques are not as heavily used in civil, environmental, and hydraulic engineering compared to their use in mechanical engineering and the aerospace industry. As the book editors correctly note, CFD courses in civil and environmental graduate and undergraduate programs are rare.

Practical guidelines for CFD in hydraulic engineering are scattered in a vast volume of literature reporting specific cases (Sotiropoulos 2015). Many researchers and practitioners have tackled a broad range of CFD applications in hydraulic engineering flows in the last decade, leading to some important insights. Still, CFD in the world of hydraulics remains an evolving and vital area of research that depends on experimental results as well numerical analysis (Stoesser 2014; Sotiropoulos 2015).

In the past decade, CFD has successfully been applied in the South Florida Water Management District (SFWMD) to solve complex real-life hydraulic engineering problems, such as

CFD can be a practical tool in complementing limited field and/or laboratory experiments and can be used to update several USACE or US Bureau of Reclamation (USBR) design manuals (e.g., Peterka 1964; USBR 1973). Compared to field or laboratory measurements, it can substantially reduce cost and time.

In conclusion, this book is a valuable and timely contribution to the CFD literature and will be appreciated by diverse civil and environmental engineering communities. While the book’s breadth of coverage is impressive, its depth of coverage is lacking when it comes to practical applications of CFD in water resources engineering in general, and in hydraulic engineering in particular.