研究目的
To explain the discrepancy in effective absorption coefficients observed in flash thermography of semitransparent solids when using polychromatic light sources and to extend the analytical model for improved accuracy.
研究成果
The study demonstrates that the wavelength dependency of absorption coefficients in semitransparent solids under polychromatic illumination necessitates an extended model with two effective absorption coefficients. This 2α model significantly improves the fit to experimental data across different thicknesses and configurations, reducing deviations in surface temperature predictions compared to the single-parameter model.
研究不足
The model assumes homogeneous, non-scattering materials and neglects radiative heat transfer and wavelength dependency in certain approximations. The fit results for the 2α model parameters may not be unique or well-defined, and the approach requires data from multiple thicknesses and configurations for accurate parameter determination.
1：Experimental Design and Method Selection:
The study uses analytical models (1α and 2α models) based on heat diffusion equations to describe temperature development in semitransparent solids under monochromatic and polychromatic illumination. The 2α model incorporates two effective absorption coefficients to account for wavelength dispersion.
2：Sample Selection and Data Sources:
Samples are films of polymer material StoPox TEP MultiTOP with thicknesses between 0.92 mm and 1.65 mm, measured at 25 positions each using an electromagnetic gauge.
3：92 mm and 65 mm, measured at 25 positions each using an electromagnetic gauge.
List of Experimental Equipment and Materials:
3. List of Experimental Equipment and Materials: IR camera (Infratec ImageIR 8800), diode laser system (LDM 500-20 by Laserline GmbH), flash lamps (Hensel Studiotechnik EH Pro 6000), and samples of StoPox TEP MultiTOP polymer.
4：Experimental Procedures and Operational Workflow:
Experiments conducted in transmission and reflection configurations. Temperature data collected using IR camera at frame rates between 100 Hz and 333 Hz. Heating sources include a monochromatic laser (935 nm wavelength, 457 ms pulse) and polychromatic flash lamps with PMMA IR filters.
5：Data Analysis Methods:
Data fitted using analytical models in Laplace domain with inverse transform algorithms (Stehfest or Abate and Whitt methods). Minimization of squared differences between experimental and modeled temperatures using simplex search method.
独家科研数据包，助您复现前沿成果，加速创新突破
获取完整内容
