Every day life is made up of unnoticed physical processes. For example, when mayonnaise is scooped straight out of the jar, it can just sit on a spoon as a solid, but apply a gentle force to it, and it spreads as a liquid, then sets up again. The process of reduction of flow resistance, known as shear thinning, is one of numerous subjects of research in City College’s Benjamin Levich Institute for Physico-Chemical Hydrodynamics.
The Levich Institute was established in 1979 by Albert Einstein Professor of Science Benjamin Levich, and was then known as the Institute of Applied Chemical Physics. A renowned physicist, Levich and his early colleagues at CCNY focused on fluid instabilities and turbulence —an irregular fluid motion—Director Jeff Morris (also Professor of Chemical Engineering) noted, “one of the classic unsolved problems of physics.”
Since its inception, the Institute has grown into a facility focused on soft matter physics, molecular dynamics simulations, interfacial science, and network and data science theory. Soft matter is a broad field that includes materials such as polymers, foods (like mayonnaise), and personal care products (e.g., shampoo), but also encompasses the flow behavior of cement and concrete (the most widely used man-made materials), while natural examples of soft matter include mud and blood.
A key research area of the Institute is rheology, defined as the study of flow, and especially of complex materials like those noted above. The three Institute Directors following Levich —Andreas Acrivos (1988-2000), Morton Denn (2001-2015), and Morris (2016-present) —all received the Society of Rheology’s highest honor, the Bingham Medal. Notably, Acrivos was awarded the National Medal of Science in 2001.
All Institute faculty have a range of interests, but a flavor of the work can be seen by a few examples of their recent work. Chemical Engineering Professor Charles Maldarelli has performed numerous studies of interfacial flows, involving materials with soft surfaces such as droplets, with broad applications in biomedical diagnostics of cells.
Photo: City College
Physics Professor Matt Shattuck has recently published work on a novel description of folding in proteins, relating this to jammed packings. Morris and the former director, Einstein Professor Emeritus Morton Denn, have for the past decade studied the
role of composition of fluids to understand how frictional interactions between particles can alter their properties, an issue critical in landslides (mud flow) and pouring of cement.
Physics Professor Joel Koplik studies how molecular interactions affect a range of fluid mechanical phenomena; this includes wetting of solids by drops of liquid, a topic recently supported by ExxonMobil toward the development of a method for taking carbon dioxide from the atmosphere and sequestering it deep underground.
While the behavior of soft matter is controlled by the smallest scale interactions, the impacts are seen in such everyday items as personal care and liquid food products, such as face cream and dressings. Much of the Institute’s work through the years has been supported by federal agencies, such as the National Science Foundation and the Department of Energy. In addition, Institute faculty provide consulting services to manufacturers, and regularly collaborate with companies across numerous sectors such as ExxonMobil, the snack food giant Mondelez, Samsung, and, on a more local level, Con Edison.
The Institute’s fields of concentration extend beyond chemical engineering and physics. Professor Hernan Maxe has made advances in the field of network science. His lab focuses on interactions in complex networks, such as the internet and the social networks within it. He is particularly interested in using online social platforms to predict and understand election outcomes. Maxe is also the founder of Kcore Analytics, which he launched in 2018 with CCNY Associate Researcher Matteo Serafino. The company utilizes AI and social network structures to track and forecast trends and identify influencers from real-time online data.
Future directions of the Levich Institute include their range of investigations involving high-performance computing, machine learning, and artificial intelligence approaches for complex systems.
“We’re working to develop theoretical descriptions of the systems, but we do a lot of our work by experiments and by simulations, numerical computational simulations. We’re heavy users of high performance computing, and at the same time also doing designed experiments to deal with specific systems, as well as characterization based on existing tools.”
The Levich Institute regularly holds seminars featuring experts from other universities. Most recently, in early October, it hosted a talk on colloid transport in porous media by Professor Amir Pahlavan from Yale University’s Department of Mechanical Engineering, while Prof. Kenneth Schweizer of the Department of Materials Science and Engineering at the University of Illinois will visit to present work on statistical physics approaches to rheology in November. These events often spark mutual inspiration and conversation among CCNY and external researchers.
“Sometimes bringing in a new approach from a colleague can actually help a great deal. So an example of this, and it’s one of the important reasons why we have regular seminars,” Morris said.
“We bring in outside people, we present our own work, but then everyone is all hearing and discussing similar things that are at the leading edge of the research, and we often come to understand, ‘oh, there are different ways to look at this.’”
While faculty are heavily involved in the Institute’s operations, Morris notes that undergraduate, graduate, postdoctoral, and visiting researchers play a significant role in research.
“We’re the constant presence, but they’re the lifeblood that comes through and makes it really happen and carries those ideas out into different places.”
Mia Euceda is an alumna of Baruch College, where they studied journalism and served as an editor for The Ticker newspaper and Refract Magazine. Their work has been published in The New York Review of Books and Treble Zine.