Accession Number : AD0661328

Title :   FIRST ORDER FREQUENCY EFFECTS IN SUPERSONIC PANEL FLUTTER OF FINITE CYLINDRICAL SHELLS.

Descriptive Note : Doctoral thesis,

Corporate Author : CALIFORNIA UNIV BERKELEY DIV OF AERONAUTICAL SCIENCES

Personal Author(s) : Li,Ting-Mau

Report Date : AUG 1967

Pagination or Media Count : 51

Abstract : The flutter boundary of a thin cylindrical shell of finite length is determined with the aerodynamic load obtained by linearized potential theory. A low frequency approximation is applied, together with some other plausible approximation, to circumvent the difficulty in evaluating a complicated convolution integral containing Bessel functions. Galerkin's method is then used to set up an eigenvalue problem equivalent to the resulting integro-differential equation. The flutter boundary, for given Mach number and circumferential mode n, corresponds to the shell thickness ratio at which the real part of any one of the eigenvalue first become non-negative. Some interesting conclusions can be drawn, at least qualitatively, through Hadamard's well known theorem on the regularity of a matrix. In particular, it is found that the most feasible circumferential mode of vibration occurs around n=7. (Author)

Descriptors :   (*PANELS, *FLUTTER), (*SUPERSONIC FLOW, FLUTTER), (*SHELLS(STRUCTURAL FORMS), FLUTTER), CYLINDRICAL BODIES, AERODYNAMIC LOADING, INTEGRAL EQUATIONS, DIFFERENTIAL EQUATIONS, VIBRATION, FREQUENCY

Subject Categories : Aerodynamics
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE