Year 2005 | Volume 12    Southern Methodist University

        Paul Krueger
        Willard Spiegelman
        David Son
        Virginia Dupuy
        Alan Brown
        Wayne Shaw
        Evelyn Parker
        Valerie F. Hunt
        Dan Orlovsky


Going With The Flow

The movement of aquatic life can appear inexplicable when viewed through the glass of an aquarium tank. But Paul Krueger believes the mechanics that jellyfish and squid use to maneuver can be applied to technology in the emerging field of “micro” vehicles.

Krueger, assistant professor of mechanical engineering, is studying a mechanical system – similar to that used by jellyfish and squid – to understand pulsatile propulsion and apply it to exotic engineering applications like micropropulsion. Krueger’s research results eventually might propel tiny vehicles (sizes of a centimeter, millimeter, or smaller) used in microsurgery, create micro-submarines for undersea caverns exploration, or maneuver small aircraft for military surveillance.

“Small flight-capable or submersible vehicles are of great technological interest because their diminutive size permits increased portability and access to otherwise inaccessible locations,” Krueger says.

Creating new propulsion schemes is “paramount to the design of micro vehicles because traditional propulsion designs, such as propellers and steady jets, become too inefficient at small scales,” he says.

Krueger believes that pulsed jets – consisting of a series of jet pulses with no flow between them – is a promising approach to developing micropropulsion capability. He plans to develop a model system that propels itself using pulsed jets generated by a volume-displacement mechanism. The behavior of this representative vehicle will help reveal how to adapt pulsed jet propulsion for small-scale vehicles.

Krueger’s research is being supported through a five-year, $400,000 Faculty Early Career Development award from the National Science Foundation (NSF), partially because of its multidisciplinary nature and potential for educating pre-college students. As part of the research, he is collaborating with a biologist who is an expert on squid biomechanics, enhancing cross-disciplinary efforts between the fields of biology and mechanical engineering.

Krueger also plans to incorporate the study of micropropulsion devices and its applications to biology, marine life, and medical applications into introductory material for mechanical engineering courses. “Illustrating applications of mechanical engineering in different fields may be a key factor in attracting new students from various backgrounds to study mechanical engineering,” he says.

Krueger joined the SMU School of Engineering in 2002 after receiving his Ph.D. in aeronautics from the California Institute of Technology.

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