Physics of Fluids
and Living Systems


The Juarez group focuses on investigating the fundamental physics behind intriguing phenomena observed in soft matter and living systems.

The two major research themes in our group are
complex fluids, such as polymer solutions, and
active matter, such as bacteria suspensions.

The following subjects are relevant to the problems we like to think about
low Reynolds number fluid mechanics • Physics of living systems • environmental science • rheology • colloid science • polymer physics • microbial ecology

We are part of the Mechanical Science and Engineering Department in the Grainger College of Engineering at the University of Illinois.

We thank the National Science Foundation for funding our coral reef restoration research.


We are a highly interdisciplinary research team with interests in the field of soft matter. Examples of soft matter include colloidal suspensions, polymer solutions, foams, granular materials, and biological materials. These materials are "soft" in the sense that they are deformed by thermal or mechanical stresses that are comparable to thermal fluctuations at room temperature.

We implement the tools of microfluidics, microscopy, high-speed imaging, and quantitative image analysis to experimentally study problems that lie at the interface of low-Reynolds numbers fluid mechanics, biophysics, and environmental science.

Our approach spans orders of magnitude in length, from single molecules to single cells to the environment, and time. We use observations in controlled fluid environments in combination with quantitative image analysis to understand physical mechanisms and chemical processes that we use to build mathematical models and predictive frameworks.

See below for a sample of ongoing and open projects in the lab.

  • Portfolio Item

    Oil degradation by marine bacteria

    How do single bacteria rid the oceans of hydrocarbon pollution?
  • Portfolio Item

    Complex fluids and polymer physics

    How do single molecules driven far-from-equilibrium affect material properties such as viscoelasticity?
  • Portfolio Item

    Oil degradation in porous media

    How do physically and chemically heterogeneous microenvironments affect hydrocarbon degradation by bacteria?
  • Portfolio Item

    Cell growth at fluid interfaces

    What is life like when trapped in two dimensions?
  • Portfolio Item

    Particle tracking and microrheology

    How small of a sample is needed to determine its material properties?
  • Portfolio Item

    Microfluidics and imaging techniques

    What new phenomena can we observe using the latest technologies?

Want to learn more?

We are always available and happy to discuss our research interests. Come visit the lab!

Meet The Team

''Més que un club''
Gabriel Juarez
Principal Investigator
Member Photo
Daniel Gysbers
Grad, Phys PhD
Topic: Larvae settlement
Member Photo
Vincent Hickl
Grad, Phys PhD
Topic: Oil biodegradation
Member Photo
Blake Langeslay
Grad, Phys PhD
Topic: Active nematics
Member Photo
Giridar Vishwanathan
Grad, ME PhD
Topic: Inertial microfluidics


  • Henry Cordes (Mech)

  • Xingjian Di (Phys)

  • Andrew Dou (Mech)

  • Courtney Seckman (Mech)

  • Interested in joining?

    We are always interested in recruiting creative and highly motivated individuals (Postdoc, graduate, and undergraduate) looking to conduct high-impact research with us.

    Prospective graduate students should follow the links for more information on the admission process.
  • College of Engineering grad programs
  • Mechanical Science and Engineering
    grad application and FAQ

  • Students already admitted to the University of Illinois should contact the PI via email including your qualifications, project of interest, and CV.


    1. Steady streaming flows in viscoelastic liquids
      G. Vishwanathan and G. Juarez
      Journal of non-Newtonian Fluid Mechanics, 271, 104143 (2019)

    2. Steady streaming viscometry of Newtonian liquids in microfluidic devices
      G. Vishwanathan and G. Juarez
      Physics of Fluids, 31, 041701 (2019)

    3. Modeling the impact of dilution on the microbial degradation time of dispersed oil in marine environments
      V. I. Fernandez, R. Stocker, and G. Juarez
      Oilfield Microbiology, CRC Press, 215-232, (2019)

    4. Designing engineering tasks for collaborative problem solving
      S. Shehab, E. Mercier, M. Kersh, G. Juarez, and H. Zhao
      12th International Conference on Computer Supported Learning, 2, 825-826 (2017)

    5. Regular and irregular splashing of drops on geometric targets
      G. Juarez, T. Gastopoulos, Y. Zhang, M. L. Siegel and P. E. Arratia
      Physics of Fluids, 24, 091105 (2012)

    6. Splash control of drop impacts with small geometric targets
      G. Juarez, T. Gastopoulos, Y. Zhang, M. L. Siegel and P. E. Arratia
      Physical Review E, 85, 026319 (2012)

    7. Mixing by cutting and shuffling 3D granular flow in spherical tumblers
      G. Juarez, I. C. Christov, J. M. Ottino and R. M. Lueptow
      Chemical Engineering Science, 73, 195-207 (2012)

    8. Extensional rheology of DNA suspensions in microfluidic devices
      G. Juarez and P. E. Arratia
      Soft Matter, 7, 9444 (2011)

    9. Transition to centrifuging granular flow in rotating tumblers: a modified Froude number
      G. Juarez, P. Chen and R. M. Lueptow
      New Journal of Physics, 13, 053055 (2011)

    10. Motility of small nematodes in wet granular media
      G. Juarez, K. Lu, J. Sznitman and P. E. Arratia
      Europhysics Letters, 92, 44002 (2010)

    11. Mixing by cutting and shuffling
      G. Juarez, R. M. Lueptow, J. M. Ottino, R. Sturman and S. Wiggins
      Europhysics Letters, 91, 20003 (2010)

    12. Granular coarsening: Phase space and evolution analogies
      G. Juarez, R. M. Lueptow and J. M. Ottino
      Physical Review E, 81, 012301 (2010)

    13. Axial band scaling for bidisperse mixtures in granular tumblers
      G. Juarez, J. M. Ottino and R. M. Lueptow
      Physical Review E, 78, 031306 (2008)

    Image and video gallery