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Updated: Jan 28, 2026
08:14
Ammonia Synthesis at Low Pressure
Published on: August 23, 2017
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Ammonia Distribution Measurement on a Hot Gas Test Bench Applying Tomographical Optical Methods
Bernhard Fischbacher1, Bernhard Lechner2, Bernhard Brandstätter3
1Kompetenzzentrum-Das Virtuelle Fahrzeug Forschungsgesellschaft mbH, Inffeldgasse 21A, 8010 Graz, Austria. bernhard.fischbacher@v2c2.at.
Sensors (Basel, Switzerland)
|February 24, 2019
Summary
This study introduces a novel device for measuring ammonia concentration distribution in diesel engine exhaust. This advancement aims to enhance exhaust aftertreatment system performance using deep ultraviolet spectroscopy.
Area of Science:
- Engineering
- Environmental Science
- Analytical Chemistry
Background:
- Accurate gas concentration measurement is crucial across various technological fields.
- Diesel engine exhaust aftertreatment systems require precise monitoring for optimal performance.
Purpose of the Study:
- To develop and validate a device for detecting ammonia concentration distribution in diesel engine exhaust.
- To improve the efficiency of exhaust aftertreatment systems through enhanced monitoring.
Main Methods:
- Utilized nondispersive absorption spectroscopy in the deep ultraviolet region.
- Employed multiple optical beams and photodiodes for high-speed (3 kHz) line concentration measurements.
- Applied tomographic techniques to solve the inverse problem and generate concentration distribution images.
Main Results:
- Achieved a detection limit of 1 ppm for ammonia.
- Demonstrated high signal-to-noise ratio with short path lengths (8 cm).
- Successfully generated time-resolved ammonia concentration distribution images.
Conclusions:
- The developed device and methods enable accurate, high-speed measurement of ammonia distribution in diesel exhaust.
- This technology can significantly contribute to optimizing exhaust aftertreatment systems.
- The tomographic approach effectively visualizes gas concentration dynamics.
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