Zhongjia Li¹, Jianfeng Pan^1,*, Hongjun Liu¹, Baowei Fan¹, Wenming Yang², Abiodun Oluwaleke Ojo¹

Energy Engineering, Vol.118, No.3, pp. 581-603, 2021, DOI:10.32604/EE.2021.014378

Abstract In order to improve the performance of the rotary engine, this paper has designed a new type of dual-pit rotary engine combustion chamber structure, and compares the combustion and emission characteristics with the rotary engine with a traditional combustion chamber. The existence of the dual-pit combustion chamber strengthens the overall vortex intensity in the cylinder, effectively promotes the mixing process of fuel and air in the cylinder, the maximum combustion pressure in the cylinder increased by 8.6%, significantly increases the diffusion combustion speed, and significantly improves the dynamic performance of the rotary engine. On this basis, the effects of fuel… More >

Chenpeng Song^1,2, Yulong Chen^3,*, Jiehao Wang^2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.120, No.3, pp. 779-797, 2019, DOI:10.32604/cmes.2019.07000

Abstract Hydraulic fracturing has been applied to enhance CBM production and prevent gas dynamical hazard in underground coal mines in China. However, affected by in situ stress orientation, hydrofracture can hardly continuously propagate within coal seam but may easily extend to the adjacent roof-floor strata, causing ineffective permeability enhancement in coal seam and increasing the risk of gas transfinite during mining coal. Thus, it is very necessary to artificially control the propagation direction of hydrofracture and make it well-aligned in large scale in coal seam. In this study, a method for controlling propagation direction of hydrofracture by multi-boreholes is investigated by… More >