Evaluation of the Energy Consumption and Fractal Characteristics of Different Length-Diameter Ratios of Coal under Dynamic Impact

Qiupeng Yuan, Lei Wang, Guangxiang Xie, Shuhao Gu, Naseer Muhammad Khan, Zhenhua Jiao and Huaiqian Liu
Additional contact information
Qiupeng Yuan: State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mine, Anhui University of Science and Technology, Huainan 232001, China
Lei Wang: State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mine, Anhui University of Science and Technology, Huainan 232001, China
Guangxiang Xie: State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mine, Anhui University of Science and Technology, Huainan 232001, China
Shuhao Gu: School of Energy and Mining Engineering, China University of Mining and Technology (Beijing), Beijing 100049, China
Naseer Muhammad Khan: State Key Laboratory of Coal Resources and Mine Safety, China University of Mining and Technology, Xuzhou 221116, China
Zhenhua Jiao: State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mine, Anhui University of Science and Technology, Huainan 232001, China
Huaiqian Liu: School of Energy and Mining Engineering, China University of Mining and Technology (Beijing), Beijing 100049, China

Energies, 2022, vol. 15, issue 15, 1-18

Abstract: Coal samples having the same diameter (50 mm) and different length-diameter ratios ( l / d ), i.e., 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, and 1.0 were tested under dynamic uniaxial impact compression using the Split Hopkinson Pressure Bar (SHPB) experimental system. This study evaluates: (a) The effects of l / d on the energy consumption law and fractal characteristics of coal crushing; (b) The effects of l / d and stress balance on energy dissipation; (c) The effects of l / d and energy consumption density on the fractal characteristics of coal crushing. The findings under different l / d are as follows: (1) The coal samples show similar stress–strain curve shapes in stages including elastic, plastic, and failure stage, which is an “open” shape, the proportion of plastic stage increases, and strain-softening occurs; (2) The dynamic compression dissipation energy and energy consumption ratio of coal shows the same trend, showing two stages with the increase of length-diameter ratio, which increases linearly in the first stage and overall decreases step-by-step; (3) The average particle size increases while fractal dimension of fragmentation decreases linearly, which endorses the decreasing trend of fragmentation degree; (4) It is determined that there is a power relationship between fractal dimension and energy dissipation density; (5) A new index Crushing Density Energy Efficiency ( CDEE ) is proposed, which can be used to characterize the rock-breaking efficiency of crushing energy consumption under different conditions. This index is inversely proportional to l / d . The research results can provide a basis for the design of top coal caving mining, and the determination of blasting parameters.

Keywords: coal; SHPB; Crushing Density Energy Efficiency ( CDEE ); length-diameter ratio ( l / d ); energy evolution; fractal (search for similar items in EconPapers)
JEL-codes: Q Q0 Q4 Q40 Q41 Q42 Q43 Q47 Q48 Q49 (search for similar items in EconPapers)
Date: 2022
References: View complete reference list from CitEc
Citations:

Downloads: (external link)
https://www.mdpi.com/1996-1073/15/15/5498/pdf (application/pdf)
https://www.mdpi.com/1996-1073/15/15/5498/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jeners:v:15:y:2022:i:15:p:5498-:d:875208

Access Statistics for this article

Energies is currently edited by Ms. Agatha Cao

More articles in Energies from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().