Hangjian Ling


Hangjian Ling, PhD

Assistant Professor

Mechanical Engineering

Curriculum Vitae
Research site




Violette Research 214


2017Johns Hopkins UniversityPhD
2013Johns Hopkins UniversityMS
2011University of Science and Technology of ChinaBS


  • Fluid Mechanics





Investigations of a fundamental and/or applied nature representing an original contribution to the scholarly research literature of the field. PhD dissertations are often published in refereed journals or presented at major conferences. A written dissertation must be completed in accordance with the rules of the Graduate School and the College of Engineering. Admission to the course is based on successful completion of the PhD comprehensive examination and submission of a formal proposal endorsed by the student's graduate committee and submitted to the EAS Graduate Program Director.

The fundamental concepts and basic principles of classical thermodynamics. The Zeroth, First and Second laws of thermodynamics are formulated with recourse to empirical observations and then expressed in precise mathematical language. These laws are applied to a wide range of engineering problems. The properties of pure substances are described using equations of state and surfaces of state. Reversible processes in gases are analyzed by means of the First and Second laws. A representative sampling of engineering applications is discussed and analyzed.

Honors enrichment course supplementing a required sophomore level course in the Mechanical Engineering curriculum. This course is open to honors students who are enrolled in the affiliated required course in the mechanical engineering curriculum. The course provides coverage of more advanced topics and more in-depth analysis of concepts than are covered in the basic class. The course may include lecture and laboratory components at the instructor's discretion.

Seminar discussions presented by faculty, graduate students, and outside speakers on topics of current research interests.

Seminar discussions presented by faculty, graduate students, and outside speakers on topics of current research interests.

Integral Transformation: Divergence Theorem; Stokes Theorem. Reynolds Transport Theorem. Navier-Stokes equations. Kelvin's theorem. Vorticity Transport. Crocco's Theorem. Viscous flow: boundary layers, buoyancy-driven flows.

Independent study under faculty supervision. Intensive literature search culminating in a technical report. Oral presentation at the option of the faculty.

Thesis research on an experimental or theoretical project in mechanical engineering under a faculty advisor. A formal thesis must be submitted to fulfill the course requirements.


Research activities

  • Mechanism of gas depletion on super-hydrophobic surfaces in turbulent flows”, National Science Foundation, $299,778, 01/01/2021 to 12/31/2023.


Research awards

  • $ 400,928 awarded by National Science Foundation for CAREER: Diffusive and Convective Gas Dissolution over Super-Hydrophobic Surfaces
  • $ 197,813 awarded by Office of Naval Research for UMassD MUST I: Anti-biofouling Property and Lifetime of Super-Hydrophobic Surfaces in Marine Environment


Research interests

  • Experimental fluid dynamics in turbulence, boundary layers, multiphase flows
  • Super-hydrophobic surfaces and the wetting dynamics
  • Collective behavior such as bird flocks, fish schools, human crowds and cell colonies
  • 3D Imaging technologies using digital holography and stereo-imaging

Select publications

See curriculum vitae for more publications

  • Ling H, McIvor GE, Vaart K van der, Vaughan RT, Thornton A, Ouellette NT (2019).
    Costs and benefits of the social relationship in the collective motion of bird flocks
    Nature Ecology and Evolution, 3(6), 943-948.
  • Ling H, Fu M, Hultmark M, Katz J (2017).
    Effect of Reynolds number and saturation level on gas diffusion in and out of a super-hydrophobic surface
    Physical Review Fluids, 2(12), 124005.
  • Ling H, Srinivasan S, Golovin K, McKinley GH, Tuteja A, Katz J (2016).
    High resolution velocity measurement in the inner part of turbulent boundary layers over super-hydrophobic surfaces
    Journal of Fluid Mechanics, 801, 670-703.

Dr. Ling is currently an Assistant Professor in Mechanical Engineering at University of Massachusetts Dartmouth. He received his PhD from Johns Hopkins University in 2017, where he studies the drag reduction of super-hydrophobic surfaces in turbulent flows. Before joining UMass Dartmouth, he was a Postdoc at Stanford University from 2017 to 2019, where he studies the collective behavior of natural bird flocks.

Dr. Ling is broadly interested in fluid dynamic problems at the interface of material, biological and environmental sciences. His lab focuses on the development of novel imaging technologies to characterize fluid flows as well as animal movements in complex environments. His overarching goal is to uncover the underlying physical laws, and harness them to solve the critical energy and environmental issues in our society. His current research areas include:

  • Applications of bio-inspired superhydrophobic surfaces in marine engineering for anti-biofouling, anti-icing, and energy saving;
  • Biofouling and attachment mechanism of marine micro-organisms on roughed and bubbled surfaces;
  • Mechanism of drag and noise productions in turbulent boundary layers over high-speed vessels;
  • Mechanism of group cohesion maintenance by social animals in turbulent and uncertain environments;
  • Holographical imaging of human cells and cancer detection;
  • Long-term three-dimensional tracking and monitoring of the foraging actives of seabirds.

Dr. Ling’s work has been published in several high-impact journals including Nature Ecology and Evolution, and Nature Communications.