APS News

December 2021 (Volume 30, Number 11)

Fluid Dynamicists Rise to the Challenges

By David Barnstone

In January 2019, dozens of researchers gathered near the base of Mont Blanc in Eastern France to discuss some of the most pressing and consequential issues of our time. The aim of the workshop at the Les Houches School of Physics was to galvanize the fluid dynamics community to use their scientific talents to advance the Sustainable Development Goals of the United Nations.

“Environmental fluid mechanics actually underlies a lot of the challenges society is facing [right now],” said Tom Peacock, professor of mechanical engineering at MIT and one of the workshop’s organizers. From climate and weather modeling to addressing oil spills and microplastics in the ocean, fluids researchers have an important role in addressing these challenges. Peacock and his colleagues, for example, recently conducted field work assessing the environmental impact of deep sea mining operations in the Pacific Ocean.

UN Sustainability goals

The workshop focused on five key areas outlined in an invited paper published in Physical Review Fluids and discussed by the authors in an online journal club hosted by APS.

Nathalie Vriend, Royal Society University Research Fellow at the University of Cambridge’s BP Institute, presented research on multiphase flows, which are happening all around us and have a direct impact on people’s lives and livelihoods: precipitation, avalanches and mudslides, and sediment transport in bodies of water, to name a few.

“We’re looking at a very complex rheology,” says Vriend. “This is not a simple Newtonian flow because of the interaction between particles and fluids.” Fortunately, recent advances in experimentation, high-speed cameras, computation, and machine learning are helping researchers tackle these questions with unprecedented precision.

Another type of flow relevant to several Sustainable Development Goals—particularly Clean Water and Sanitation, Vulnerable Cities and Communities, Climate Action, and Life Below Water—is the transport of heat through the layers of the atmosphere and ocean. A “gigantic” amount of heat—on the order of petawatts—is moved through the planet in this way, according to C.P. Caulfield, also at Cambridge, who says understanding stratified mixing is essential for ensuring the sustainability of life on Earth.

Of course, our oceans are not only transporting heat. Nadia Pinardi, an oceanographer at the University of Bologna, presented research on how environmental contaminants like plastics and oil are moved by ocean eddies. Studies of the transport—and ultimately the collection—of pollutants in the oceans are critical for planning adaptation and mitigation efforts.

Pollutants also disperse through cities, which are expected to house about two-thirds of the world’s population by 2050. Urbanization presents unique challenges to modern life that fluid mechanics researchers can address through research into urban wind patterns, building ventilation, and “heat islands,” says Stanford University civil engineer Catherine Gorle. “It’s really important for us to think about how we actually use these predictions to then have that impact” by combining our data sources—field work, simulations and laboratory experiments—and working with key stakeholders, including the people living in cities, building owners and operators, and municipalities to implement changes. “Often times that is really the big challenge.”

A common challenge across these areas is reducing uncertainties and processing ever growing amounts of data. Nowhere is that challenge clearer than in weather and climate modeling. Peter Bauer of the European Centre for Medium-Range Weather Forecasts calls this an “extreme computing problem.” The ultimate goal would be to develop a digital twin of Earth that would provide an interactive tool built on a reliable information system of both simulation and observational data. All of this relies on a “proper representation of the Earth system, at the core of which sits proper fluid dynamics.”

Claudia Cenedese, senior scientist at the Woods Hole Oceanographic Institution, concluded the discussion: “Scientists can help society by tackling these Grand Challenges but they need to collaborate, interact, and engage with experts in other fields and policy makers.”

To view a recording of the journal club, visit the YouTube video page.

The author is APS Head of Public Relations.

APS encourages the redistribution of the materials included in this newspaper provided that attribution to the source is noted and the materials are not truncated or changed.

Staff Science Writer: Leah Poffenberger
Contributing Correspondents: Sophia Chen, Alaina G. Levine

December 2021 (Volume 30, Number 11)

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Articles in this Issue
Neutron Lifetime Measurement Could Help Probes of the Standard Model
Fluid Dynamicists Rise to the Challenges
Martin Blume 1932 - 2021
APS Hosts Quantum Crossing Event to Educate Students About Quantum Careers
New Grant Seeks to Provide Professional Development to Future Physics Leaders
Harvesting a Career in Soil Physics to Serve Humanity
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Reviewing Peer Review
This Month in Physics History
News from Government Affairs
FYI: Science Policy News From AIP
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