X. Liu, S. Liu, and P. Tang, "Coal fragment size model in cutting process," Powder Technology, vol. 272, pp. 282-289, 2015.Liu X.H., Liu S.Y., Tang P.: Coal fragment size model in cutting process, In: Powder Technology, Vol. 272, 2015, pp.282-289....
an evolutionary model in which an enormous cloud of gas and dust began to condense to form what are now Population II stars. The remaining gas and dust then collapsed, either suddenly or in stages, into the relatively thin disk in which Population I stars were (and still are being) formed...
Note that w<r is the cumulative mass fraction of fragments whose size is less than the corresponding sieve size r. 4. Numerical study 4.1. Constitutive model of coal material In order to numerically investigate the coal failure process, a brittle damage model in LS-DYNA is implemented to ...
As part of an effort to understand the mechanics of fine fragment formation in coal, which is important in studies of respirable dust due to mining, fracture toughness measurements and the strain energy density (SED) theory were applied to calculate the crush zone size under a cutting tool in...
In the mining industry, the use of continuous mining, longwall mining, and shortwall mining has been growing in relation to conventional mining. The former methods utilize high speed rotating bits to remove the coal from the working face, and this generates a wide range of fragment sizes. ...
deflection of the coal wall is relatively small, so the gravity of the coal wall itself is not considered; the compression deformation of the coal wall in the vertical direction has less effect on its deflection, so this factor is not considered, and the simplified model is shown in Figure ...
2.4. Characterization of Fragment Size and Shape Distributions The determination of distribution models is the key to characterizing the size distribution of coal fragments. In this study, the cumulative distribution model of the generalized extreme value (GEV) distribution and fractal theory are adopted...
The process of roof cutting and gangue bulking would then be the process of the surrounding rock movement of GERRC, which mainly includes: (1) constant resistance and large deformation anchor cable support and pre-splitting blasting before mining, as shown in Figure 2a; (2) immediate roof coll...
The average particle size dvn of the n-th group is determined by calculating the average of the largest and smallest particle sizes in the particle size range. In the case of the >20.0 mm group, the average particle size is selected as 20.0 mm since the maximum size is unknown. Wsn rep...
The smaller the particle size of the briquette sample is, the denser the specimen, the stronger the amplitude and energy of the single effective MS signal formed during the damage process of the coal sample, the longer the time for crack extension from the near-threshold stage to the high-...