Influence of the contraction angle on the injection of large coal particles

The drum is the working mechanism of the coal shearer, and the coal loading performance of the drum is very important for the efficient and safe production of coal mine. In order to study the coal loading performance of the shearer drum, a discrete element model of coupling the drum and coal wall was established by combining the results of the coal property determination and the discrete element method. The movement of coal particles and the mass distribution in different areas were obtained, and the coal particle velocity and coal loading rate were analyzed under the conditions of different helix angles, rotation speeds, traction speeds and cutting depths. The results show that with the increase of helix angle, the coal loading first increases and then decreases; with the increase of cutting depth and traction speed, the coal loading rate decreases; the increase of rotation speed can improve the coal loading performance of drum to a certain extent. The research results show that the discrete element numerical simulation can accurately reflect the coal loading process of the shearer drum, which provides a more convenient, fast and low-cost method for the structural design of shearer drum and the improvement of coal loading performance.

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Loading Performance of a Novel Shearer Drum Applied to Thin Coal Seams

Energies ◽

10.3390/en14020358 ◽

2021 ◽

Vol 14 (2) ◽

pp. 358

Author(s):

Kuidong Gao ◽

Xiaodi Zhang ◽

Liqing Sun ◽

Qingliang Zeng ◽

Zhihai Liu

Keyword(s):

Rotational Speed ◽

Production Efficiency ◽

Loading Rate ◽

Positive Impact ◽

Structural Parameters ◽

Helix Angle ◽

Structure Design ◽

Coal Seams ◽

Coal Particles ◽

Relationship Of

The poor loading performance of shearer drums restricts the development and production efficiency of coal in thin coal seams. Changing operation and structural parameters can improve the drum’s loading performance to some extent, but the effect is not obvious. A two-segment differential rotational speed drum (TDRSD) was proposed after analyzing the drum’s influence mechanism on coal particles. To further reveal the drum’s coal loading principle, the velocity, particles distribution, and loading rate were analyzed. The effect of the matching relationship of the rotational speed and helix angle between the front and rear drum are also discussed. The results show that a lower front drum rotational speed had a positive impact on improving the loading performance, and the loading rate first increases and then decreases with the increase in rear drum rotational speed. The optimal loading performance was obtained in the range 60–67.5 rpm. The front drum’s helix angle had no evident effect on loading performance, and the loading rate increase with the increase in the rear drum’s helix angle. The results provide a reference and guidance for operation parameters selection, structure design, and drum optimization.

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A study of the hydrodynamics of steam-assisted coal particles removal

International Journal of Energy and Environmental Engineering ◽

10.1007/s40095-020-00368-8 ◽

2021 ◽

Author(s):

Afrasyab Khan ◽

Khairuddin Sanaullah ◽

Spiridonov Evgeny Konstantinovich ◽

Khabarova Darya Fedorovna ◽

Andrew Ragai Henry Rigit ◽

...

Keyword(s):

Coal Particles

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Effect of pressure on the swelling of density separated coal particles

Fuel ◽

10.1016/j.fuel.2004.06.035 ◽

2005 ◽

Vol 84 (10) ◽

pp. 1238-1245 ◽

Cited By ~ 22

Author(s):

Vladimir Strezov ◽

John A. Lucas ◽

Terry F. Wall

Keyword(s):

Effect Of Pressure ◽

Coal Particles

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Considerations on Designing Artificial Muscle Working at High Pressure

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.268-270.1457 ◽

2012 ◽

Vol 268-270 ◽

pp. 1457-1463

Author(s):

Li Chao Wang ◽

Xiao Dong Wang

Keyword(s):

High Pressure ◽

Material Properties ◽

Weight Ratio ◽

Artificial Muscle ◽

Force Output ◽

Compact Structure ◽

Small Power ◽

Small Force ◽

Working Principle ◽

Contraction Angle

Artificial muscle is a new style of actuator with novel working principle, which owns the advantages of compact structure, high power-to-weight ratio, compliance and easy application. Pneumatic artificial muscle (PAM) is usually used in robotics, medical auxiliaries and other small force output occasions nowadays. However, it suffers problems of small power, hysteresis and poor repeatability. A kind of artificial muscle working at high pressure was researched. Different muscle styles are compared and MicKibben structure is selected while fluid media is determined. Furthermore, factors of geometry and material properties, which limit the ultimate pressure, are analyzed. Formulas and simulations verify the influence of limitation and help to calculate key parameters of 18MPa artificial muscle. Data show that it is possible in theory to design high pressure artificial muscle by overall consideration of initial diameter, initial contraction angle and material properties, initial length only influent the stroke.

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