کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
4452958 | 1312119 | 2009 | 12 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Directional dependence of thermal emission from nonspherical carbon particles Directional dependence of thermal emission from nonspherical carbon particles](/preview/png/4452958.png)
The directional intensity distribution of thermal emission from nonspherical particles can be predicted in the geometric optics limit using the Kirchhoff's law, or, in general case, using the Rytov's theory based on the fluctuation–dissipation theorem. This study demonstrates the first experimental evidence of the directional variation of thermal emission from nonspherical particles of a size smaller than the geometric optics limit. We used a method of laser-induced incandescence with multi-angle detectors to observe the directional dependences of thermal emission from individual carbon particles. For laboratory carbon particles with various shapes, the measured directional dependences of thermal emission were consistent with theoretical calculations for model nonspherical particles. This study provides a new physical principle for measuring the shape of aerosols according to the directional dependence of their thermal emission and is especially useful for online, in situ shape classification of carbon particles.
Journal: Journal of Aerosol Science - Volume 40, Issue 9, September 2009, Pages 790–801