Laser induced forced motion and stress waves in plates and shells
Abstract
A combined analytical and experimental program was conducted to study the forced, thermoelastic motion of plates due to laser irradiation. The first part of the theoretical study deals with modeling and analysis of a simply supported rectangular plate irradiated by a laser beam at an arbitrary point. The initial phase of the response is modeled as a localized effect in the vicinity of the irradiated area. It is shown that in this area, a dilation wave is set up which propagates in the direction of the plate thickness. This causes periodic in-plane stresses (tension and compression) which are, however, small (by at least 2 orders of magnitude) compared to the gross flexural motions associated with the latter phase of the plate response. The flexural response was predicted using three different theories: (a) three-dimensional elasticity theory, (b) classical plate theory, and (c) improved plate theory (incorporating shear deformation and rotatory inertia effects). All three gave the same time history response with less than 0.1% differences among them in the amplitude of vibration. The second part of the analytical study involves the boundary value problem of a clamped circular plate subject to normal laser irradiation at the center. An exact solution of the dynamic response was obtained via a series representation. The results provided the theoretical base for the experimental validation effort.
- Publication:
-
State Univ. of New York, Stony Brook Report
- Pub Date:
- August 1981
- Bibcode:
- 1981suny.rept.....R
- Keywords:
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- Deformation;
- Elastic Plates;
- Irradiation;
- Lasers;
- Shells (Structural Forms);
- Stress Waves;
- Thermoelasticity;
- Boundary Value Problems;
- Dynamic Response;
- Plane Stress;
- Shear Properties;
- Thickness;
- Lasers and Masers