摘要
利用吉林华兴矿煤制成成型煤样,在ZYS-1型三轴渗透仪上对型煤试样进行渗流试验。通过试验研究了围压、轴压及温度对成型煤样的渗透率影响,结果表明:①随着围压增加,煤样渗透率降低。②偏应力对煤渗透率有很大影响。在围压条件下,随着偏应力(轴压)增加,煤样先发生弹性压缩,渗透率降低,当偏应力增加到一定程度,煤样破坏,伴随着剪切扩容及孔隙和裂隙空间增加,渗透率随之增加。因此,低围压下煤样的渗透率呈"V"型变化,高围压下,煤样的渗透率单调减小。③温度对煤中气体的流动有显著影响。温度升高,一方面瓦斯气体的动力黏度增加,另一方面煤内固体颗粒体积膨胀,减小了孔隙和裂隙空间,阻碍气体的流动。
The standard coal briquette specimens from Huaxing Mine, in Jilin, were made. The permeability test was performed in ZYS- 1 equipment for the measurement of permeability to study the effects of confining stress, axial stress and temperature on permeability of coal briquette specimens. The results show that with the increasing confined stress, the permeability of coal briquette specimen decreases. The permeability of coal is greatly effected by differential stress. Under the eonditon of confined stress, with increasing differential stress （ axial stress） the permeability of the specimen decreases due to the elastic contraction. When the specimen failed due to increasing differential stress their porosity volumes increase due to dilation, and the permeability also increases. Therefore the permeability of samples takes on ＂V＂ curve under low confined stress. However the permeability decreases under high confining stress. The flow of methane in coal is greatly effected by temperature. When the temperature increases, on one hand the kinematic vis- cosity of methane increases. On the other hand the grains of coal swell and lead to contraction of flow space and reduc- tion of permeability.
出处
《煤炭学报》
EI
CAS
CSCD
北大核心
2013年第6期936-941,共6页
Journal of China Coal Society
基金
国家自然科学基金资助项目(51274079
51274110
51174106)
关键词
围压
温度
偏应力
成型煤样
渗透率
confining stress
temperature
differential stress standard coal briquette specimen
permeability
