Influences of Coal Properties on the Principal Permeability Tensor during Primary Coalbed Methane Recovery: A Parametric Study

Figure 13

Division of the 2DDP domain in terms of variation patterns of principal permeabilities with respect to increasing . In Domain i, the principal permeabilities increase monotonically with an increase in . In Domain ii, the principal permeabilities vary nonmonotonically with an increase in , and the curve of each principal permeability has one maximum point. In Domain iii, the principal permeabilities evolve nonmonotonically with an increase in , and the curve of each principal permeability has one minimum point. In Domain iv, the principal permeabilities decrease monotonically with an increase in .

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