A Note on Flapping Flight with Surging

  • E. C. James


A two-dimensional, unsteady, inviscid, incompressible wing theory is developed for a wing at constant angle of incidence executing “small” heaving and “large” surging displacements. The relative order of magnitude of the displacements are referenced to a normalized semichord of unity. The heave-surge motion is assumed to give rise to a constant mean forward self-propulsion speed which is a free parameter in the analysis. The results develop the long-time periodic values and the time-averaged values of lift, moment, thrust, power-input necessary to sustain the motion, the useful rate of working and the rate of energy wastage in the fluid.


Vortex Sheet Vortex Wake Forward Speed Inertial Coordinate System Suction Force 
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Copyright information

© Springer Science+Business Media New York 1975

Authors and Affiliations

  • E. C. James
    • 1
  1. 1.Naval Ship Research and Development CenterBethesdaUSA

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