CNCS Center for Nonlinear and Complex Systems
   Search Help Login pdf version printable version

Earl H Dowell, William Holland Hall Professor, Dean Emeritus of Mechanical Engineering and Materials Science and Director of Graduate Studies

Earl H Dowell

Professor Dowell's principal teaching interest and research activity is in the field of aeroelasticity - which is the study of the dynamic interaction between an aerodynamic flow and an elastic structure, such as aircraft wings in high speed flight, long span bridges and tall buildings responding to wind loadings, or airflow through the mouth and lungs. Dr. Dowell has also done research in acoustics, nonlinear dynamics, structural dynamics, and unsteady aerodynamics.

Professor Dowell's major research accomplishments include the first definitive research monograph on the aeroelasticity of plates and shells, the first derivation and solution of the nonlinear equations of motion for a helicopter rotor blade (the Hodges-Dowell equations), and work with Professor Kenneth Hall and several graduate students and post-doctoral fellows on reducing the dimensions of mathematical models for very complex high-dimensional fluid/structural systems. Professor Dowell teaches undergraduate and graduate courses on dynamics and aeroelasticity.

Here are six short videos showing experimental aeroelastic models undergoing limit cycle oscillations in the Duke wind tunnel.

  1. An airfoil with a nonlinear freeplay in the connection from the main airfoil to the trailing edge control surface.
  2. A delta wing with a strong structural nonlinearity as a result of tension in the mid-plane of the plate-like wing induced by bending of the wing out of its initially undeformed plane.
  3. A very high aspect ratio wing that behaves as a beam with double bending (both transverse to and in-line with the aerodynamic flow field) and twisting. A nonlinear coupling among double bending and twisting occurs. Also the aerodynamic flow field experiences separation due to the large motions involved.
  4. A delta wing with an external store, flutter and limit cycle oscillations.
  5. LCO and Flutter of WingStore model
  6. Flapping Flag Flutter

Contact Info:
Office Location:  185 Hudson Hall
Office Phone:  +1 919 660 5302
Email Address: send me a message
Web Page:  http://www.math.duke.edu/cncs/~dowell

Teaching (Fall 2008):

  • ME 210.01, INTERMEDIATE DYNAMICS
Specialties:

Technology Transfer
Aerodynamics
Chaos, Dynamics
Policy, Science and Engineering
Acoustics
Aerospace
Aeroelasticity
Nonlinear Systems
Research Interests:

Broad field of aeroelasticity, acoustics, nonlinear dynamics, structural dynamics, and unsteady aerodynamics.

Recent Publications   (More Publications)

  1. Tang, D. and Dowell, E.H., Aerodynamic flow control of an airfoil with small trailing-edge strips, J. Aircr. (USA), vol. 43 no. 6 (2006), pp. 1854 - 66 [1.18969]  [abs]
  2. Thomas, Jeffrey P. and Dowell, Earl H. and Hall, Kenneth C., Using automatic differentiation to create a nonlinear reduced order model of a computational fluid dynamic solver, Collection of Technical Papers - 11th AIAA/ISSMO Multidisciplinary Analysis and Optimization Conference, vol. 4 (2006), pp. 2437 - 2449, Portsmouth, VA, United States  [abs]
  3. Attar, P.J. and Dowell, E.H., Erratum: Stochastic analysis of a nonlinear aeroelastic model using the response surface method (Journal of Aircraft (2006) (1044)), Journal of Aircraft, vol. 43 no. 6 (2006), pp. 1959 - [1.28838]
  4. Dowell, E.H. and Deman Tang, Experimental and theoretical study of gust response for a wing-store model with freeplay, J. Sound Vib. (UK), vol. 295 no. 3-5 (2006), pp. 659 - 84 [024]  [abs]
  5. Attar, P.J. and Dowell, E.H. and White, J.R. and Thomas, J.P., Reduced order nonlinear system identification methodology, AIAA J. (USA), vol. 44 no. 8 (2006), pp. 1895 - 904 [1.16221]  [abs]