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Lock-In Thermal Test Simulation, Influence, and Optimum Cycle Period for Infrared Thermal Testing in Non-Destructive
António Ramos Silva1,2, Mário Vaz1,2, Sofia Leite3
1Faculty of Engineering, University of Porto, 4200-465 Porto, Portugal.
Sensors (Basel, Switzerland)
|January 8, 2023
Summary
Lock-in thermal tests (LTTs) effectively detect composite material defects. Optimizing the stimulation wave
Area of Science:
- Materials Science
- Non-Destructive Testing
- Thermal Analysis
Background:
- Lock-in thermal tests (LTTs) are crucial for defect detection in composite materials.
- The cycle period of the stimulation wave significantly impacts LTT performance.
Purpose of the Study:
- To investigate the influence of the stimulation wave's cycle period on amplitude-phase results in LTTs.
- To develop predictive models for thermal behavior in composite materials.
Main Methods:
- Conducted numerical simulations and laboratory experiments on poly(methyl methacrylate) (PMMA) and carbon fiber-reinforced polymers (CFRPs).
- Validated simulation parameters using laboratory-derived heat transfer data (input/output heat).
- Analyzed heat flow dynamics within samples of varying geometries.
Main Results:
- Developed prediction surfaces and equations correlating sample thickness and cycle period with amplitude and phase.
- Demonstrated the predictive capability of these models through validation with new experimental data.
- Quantified the impact of cycle period on thermal wave propagation and defect detection sensitivity.
Conclusions:
- The developed prediction models offer a reliable reference for optimizing LTT parameters in research and industry.
- Accurate characterization of thermal properties through LTTs enhances composite material quality control.
- This study provides a foundation for advanced defect analysis in composite structures using LTTs.
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