Experimental and Analytical Investigation of the Flutter of Flat Built-up Panels Under Streamwise Inplane Load

Experimental and Analytical Investigation of the Flutter of Flat Built-up Panels Under Streamwise Inplane Load

Author: Robert W. Hess

Publisher:

Published: 1970

Total Pages: 98

ISBN-13:

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The flutter of 13 panels subject to streamwise inplane load at Mach numbers of 1.57 and 1.96 has been investigated. Panel length-width ratios ranged from 1 to 4.2. The experimental flutter boundary was compared with an analytical flutter boundary for six of the panels. Damping, both aerodynamic and structural, was found to have a pronounced effect on the analytical flutter boundary. The agreement between analysis and experiment was dependent upon how structural damping was introduced in the formulation of the problem.


Thermoelastic Damping and Its Effect on Flutter of Stressed Panels Situated in a Supersonic Airflow

Thermoelastic Damping and Its Effect on Flutter of Stressed Panels Situated in a Supersonic Airflow

Author: R. C. Shieh

Publisher:

Published: 1971

Total Pages: 44

ISBN-13:

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The effects of material damping on flutter of stressed rectangular panels are studied within the context of linear thermoelasticity theory. The closed-form expression for the thermoelastic (material) damping coefficient is obtained as a function of frequency, panel temperature and dimensions, and material properties. The solution of the stability boundary-value problem is obtained by use of a generalized Galerkin method in the cross-stream direction which reduces the governing partial differential equations to a system of ordinary differential equations in the streamwise direction. These equations are then solved exactly. Numerical results are given for the thermoelastic damping coefficients and for the flutter speeds of partially and fully clamped panels subjected to midplane stress.