A detailed study on the micro-explosion of burning iron particles in hot oxidizing environments
(2022) In Combustion and Flame 238.- Abstract
As a promising carbon-free fuel, iron powder can directly combust with air and has great potential to provide clean and high-grad heat for various applications. The combustion characteristics of iron particles are of great significance for developing iron combustion model, designing efficient combustor, and optimizing combustion technologies. In this work, the micro-explosion behavior of burning iron particles was experimentally investigated based on optical diagnostics. With two high-speed cameras operating at 10,000 frames per second, the three-dimensional (3D) motion and mean surface temperature of burning iron particles during the micro-explosion process were measured using the stereo imaging technique and two-color pyrometry,... (More)
As a promising carbon-free fuel, iron powder can directly combust with air and has great potential to provide clean and high-grad heat for various applications. The combustion characteristics of iron particles are of great significance for developing iron combustion model, designing efficient combustor, and optimizing combustion technologies. In this work, the micro-explosion behavior of burning iron particles was experimentally investigated based on optical diagnostics. With two high-speed cameras operating at 10,000 frames per second, the three-dimensional (3D) motion and mean surface temperature of burning iron particles during the micro-explosion process were measured using the stereo imaging technique and two-color pyrometry, respectively. The probability of micro-explosions in different oxidizing environments were statistically studied. Three distinct micro-explosion modes have been observed. The results showed that the micro-explosion of burning iron particles heavily depended on oxygen concentration. The micro-explosion would slightly reduce the particle surface temperature by 30–70 K within 0.5 ms, since a lot of smaller fragments were produced. In addition, the 3D velocity of most fragments would sharply increase to 2–6 times within 0.2 ms after the micro-explosion occurred. Regarding the mechanism of the micro-explosion, three types of potential gas sources inside the particle were discussed. The sharp gradients of gas temperature and oxygen concentration may facilitate the rapid increase of the internal pressure in the particle, which eventually causes the micro-explosion.
(Less)
- author
- organization
- publishing date
- 2022
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Iron particle combustion, Micro-explosion, Optical diagnostics, Stereo imaging, Two-color pyrometry
- in
- Combustion and Flame
- volume
- 238
- article number
- 111755
- publisher
- Elsevier
- external identifiers
-
- scopus:85118784119
- ISSN
- 0010-2180
- DOI
- 10.1016/j.combustflame.2021.111755
- language
- English
- LU publication?
- yes
- additional info
- Publisher Copyright: © 2021
- id
- 53cb63ad-d0b7-47aa-8889-c6ed572e7be5
- date added to LUP
- 2021-12-01 00:14:46
- date last changed
- 2022-10-31 14:59:22
@article{53cb63ad-d0b7-47aa-8889-c6ed572e7be5, abstract = {{<p>As a promising carbon-free fuel, iron powder can directly combust with air and has great potential to provide clean and high-grad heat for various applications. The combustion characteristics of iron particles are of great significance for developing iron combustion model, designing efficient combustor, and optimizing combustion technologies. In this work, the micro-explosion behavior of burning iron particles was experimentally investigated based on optical diagnostics. With two high-speed cameras operating at 10,000 frames per second, the three-dimensional (3D) motion and mean surface temperature of burning iron particles during the micro-explosion process were measured using the stereo imaging technique and two-color pyrometry, respectively. The probability of micro-explosions in different oxidizing environments were statistically studied. Three distinct micro-explosion modes have been observed. The results showed that the micro-explosion of burning iron particles heavily depended on oxygen concentration. The micro-explosion would slightly reduce the particle surface temperature by 30–70 K within 0.5 ms, since a lot of smaller fragments were produced. In addition, the 3D velocity of most fragments would sharply increase to 2–6 times within 0.2 ms after the micro-explosion occurred. Regarding the mechanism of the micro-explosion, three types of potential gas sources inside the particle were discussed. The sharp gradients of gas temperature and oxygen concentration may facilitate the rapid increase of the internal pressure in the particle, which eventually causes the micro-explosion.</p>}}, author = {{Huang, Jianqing and Li, Shen and Sanned, David and Xu, Leilei and Xu, Shijie and Wang, Qian and Stiti, Mehdi and Qian, Yong and Cai, Weiwei and Berrocal, Edouard and Richter, Mattias and Aldén, Marcus and Li, Zhongshan}}, issn = {{0010-2180}}, keywords = {{Iron particle combustion; Micro-explosion; Optical diagnostics; Stereo imaging; Two-color pyrometry}}, language = {{eng}}, publisher = {{Elsevier}}, series = {{Combustion and Flame}}, title = {{A detailed study on the micro-explosion of burning iron particles in hot oxidizing environments}}, url = {{http://dx.doi.org/10.1016/j.combustflame.2021.111755}}, doi = {{10.1016/j.combustflame.2021.111755}}, volume = {{238}}, year = {{2022}}, }