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Detection of flame radicals using light-emitting diodes.
Stefan Schorsch1, Johannes Kiefer, Alfred Leipertz
1Lehrstuhl für Technische Thermodynamik and Erlangen Graduate School in Advanced Optical Technologies (SAOT), Universität Erlangen-Nürnberg, Germany.
Applied Spectroscopy
|December 15, 2010
Summary
Ultraviolet Light-Emitting Diodes (LEDs) show promise for flame diagnostics, offering a stable, reliable, and cost-effective alternative to lasers for detecting radicals like OH and CH in combustion. These LEDs provide consistent spectral output after a brief warm-up period.
Area of Science:
- Spectroscopy
- Combustion Science
- Optical Diagnostics
Background:
- Lasers are widely used for combustion diagnostics but have limitations.
- There is a demand for cost-effective, stable, and reliable light sources for spectroscopic applications.
- Infrared LEDs have previously shown potential for spectroscopic uses.
Purpose of the Study:
- To investigate the feasibility of using ultraviolet Light-Emitting Diodes (LEDs) for flame diagnostics.
- To detect hydroxyl (OH) and methylidyne (CH) radicals in premixed methane/air flames using UV LEDs.
Main Methods:
- Utilized ultraviolet LEDs as the light source for flame diagnostics.
- Focused on detecting OH and CH radicals in premixed methane/air flames.
- Monitored LED emission stability and spectral characteristics over time.
Main Results:
- Demonstrated the successful detection of OH and CH radicals using UV LEDs.
- Observed stable LED emission after a warm-up period of a few minutes.
- Confirmed stable spectral characteristics of the LEDs during a 24-hour test period.
Conclusions:
- Ultraviolet LEDs are a viable tool for flame diagnostics.
- UV LEDs offer a stable, reliable, and potentially low-cost alternative to traditional laser-based methods.
- The findings support the use of UV LEDs for spectroscopic detection of radicals in combustion environments.
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