A Look at Locomotion: Thrust Augmentation and Slippery Surfaces

Academic Track

with Paul Krueger,
Dean of the College of Engineering,
University of North Texas

February 20, 2026
12:30 PM (refreshments start at 12:00 PM)
Goodwin 190

Fluid dynamic propulsion appears in a variety of technological settings from ships to supersonic aircraft and supports one of the most reliable modes of transportation in the modern world. Aquatic locomotion in the animal world relies on similar physics but manifests in a greater variety of designs with, in some ways, more complex behavior. The challenges of efficiency and overcoming drag determined by the vehicle/animal configuration are common to both. Considering squid as a model organism, the core propulsion mode is a pulsatile jet. Jet pulses engender vortex ring formation, which provides augmented thrust due to additional fluid accelerated during the vortex formation process. A consequence is higher propulsive efficiency, which is observed in both biological and robotic squid swimming for a wide range of scales (animal/vehicle sizes) and has implications for bioinspired propulsion. An additional approach to modify propulsive performance is surface modification that produces slip flow. A novel approach to achieve slip flow at surfaces is investigated experimentally and computationally, illustrating both significant viscous drag reduction potential and an ability to modify vortex ring formation in pulsed jets to support higher thrust in lower Reynolds number configurations.

As the Dean of the College of Engineering, Dr. Paul Krueger oversees five academic departments: Biomedical Engineering, Computer Science and Engineering, Electrical Engineering, Materials Science and Engineering, and Mechanical Engineering. He is a recipient of the Rolf D. Buhler Memorial Award in Aeronautics, the Richard Bruce Chapman Memorial Award for distinguished research in hydrodynamics, the Faculty Early Career Development (CAREER) Award from the National Science Foundation, the American Society of Mechanical Engineers North Texas Section Young Engineer of the Year Award and the Ford Senior Research Fellowship. Dr. Krueger earned his bachelor’s degree in mechanical engineering from the University of California at Berkeley and his master’s degree and Ph.D. in aeronautics from the California Institute of Technology.