The Effects of Vertical Gusts on an Elastic Wing

Citation

Sparks, Brian Orville (1940) The Effects of Vertical Gusts on an Elastic Wing. Master's thesis, California Institute of Technology. doi:10.7907/20SK-0031. https://resolver.caltech.edu/CaltechETD:etd-11142008-144847

Abstract

The case of a wing flexible in bending and rigid in torsion entering a vertical gust is treated by consideration of the corresponding two-dimensional case. The bending stiffness of the wing is expressed as a spring constant, the aerodynamic forces acting are taken from the two-dimensional theory of airfoils in non-uniform motion, and the differential equation of motion of the wing is solved by operational methods.

Cases of sharp-edged and exponentially graded gusts are considered, and in each case the deflection is calculated in dimensionless form for three values of a dimensionless stiffness parameter. As a numerical example these results are put into dimensional form for a wing whose elastic properties are supposed to be typical of modern airplane wings.

The results obtained for the cases considered show only in one instance a maximum deflection greater than the steady-state value. Even in the sharp-gust case the deflection increases comparatively slowly following the entrance of the wing into the gust. The effects of grading the gust are to decrease slightly the rate of deflection and to reduce the amplitude of the oscillations produced by the gust.

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