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采用数值模拟的方法,分析了煤层气羽状水平井的增产机理,指出羽状水平井的主支和分支在地层中广泛均匀延伸,使整个控制区域地层压力均匀、快速下降,增大了气体解吸扩散的机会,是羽状分支水平井促使煤层气产量提高的根本原因．讨论了渗透率、朗谬尔常数、吸附时间等地层参数对羽状水平井煤层气产量的影响,并得到结论：地层绝对渗透率越大,相渗曲线越陡,残余气饱和度越小,含气饱和度越高,地层压力越大,对气产出越有利；朗氏常数通过改变等温吸附线在地层压力变化范围内的缓陡程度决定吸附量改变幅度的大小,从而影响气产量的变化,吸附时间对直井开采前期气产量到达高峰期的时间长短有影响,而对于羽状水平井,吸附时间对产量的变化几乎没有影响．
The numerical simulation method is used to analyze the stimulation mechanism of coalbed plume horizontal wells. It is pointed out that the main branch and branch of plume horizontal well extend widely and evenly in the formation, which makes the formation pressure of the control area uniform and rapidly decrease, The opportunity of desorption and diffusion is the fundamental reason for the increase of coalbed methane production in pinnate horizontal wells. The effects of formation parameters such as permeability, Langmuir constant and adsorption time on CBM production in plume horizontal wells are discussed. It is concluded that the larger the absolute permeability of formation is, the steeper the phase infiltration curve and the smaller the residual gas saturation, The higher the gas saturation, the higher the formation pressure, and the more favorable the gas production. The Lang’s constant determines the magnitude of the change in adsorption capacity by changing the gradual steepness of the isothermal adsorption line within the pressure range of formation pressure, thus affecting the gas production The change and adsorption time have an impact on the length of time when the gas production reaches its peak during the early period of vertical well production. For the plume horizontal wells, the adsorption time has little effect on the change of output.