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Higher harmonic generation in nonlinear waveguides of arbitrary cross-section
Ankit Srivastava1, Ivan Bartoli, Salvatore Salamone
1Department of Structural Engineering, University of California, San Diego, La Jolla, California 92093, USA.
The Journal of the Acoustical Society of America
|December 2, 2010
Summary
This study extends double harmonic generation analysis to complex waveguide shapes using a hybrid analytical-numerical method. This enables studying nonlinear guided waves in structures like rail tracks for applications such as thermal stress measurement.
Area of Science:
- Solid Mechanics
- Wave Propagation
- Materials Science
Background:
- Analytical solutions for nonlinear guided waves exist for simple geometries.
- These solutions explain cumulative double harmonic generation.
- Existing methods are limited to basic waveguide cross-sections.
Purpose of the Study:
- To generalize the analysis of double harmonic generation to complex waveguide geometries.
- To combine analytical methods with semi-analytical finite element models.
- To investigate nonlinear guided waves in arbitrary cross-sections, including rail tracks.
Main Methods:
- Integration of general analytical solutions with semi-analytical finite element models.
- Application to waveguides with arbitrary cross-sections.
- Validation against analytical solutions for simple geometries.
Main Results:
- A generalized method for analyzing double harmonic generation in complex waveguides.
- Successful application to a rail track geometry.
- Demonstration of the method's capability to handle intricate cross-sections.
Conclusions:
- The hybrid approach effectively extends nonlinear guided wave analysis to complex geometries.
- This method facilitates the study of phenomena like thermal stress in rails using nonlinear guided waves.
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