采空区流场非达西渗流一种新的迭代算法

对Bachmat非线性渗流方程求解问题，结合采空区问题的力学特点，提出基于变渗透率达西 (Darcy)渗流求解非线性渗流的迭代算法. 建立了冒落采空区非线性漏风流态的有限元数 值模型，通过对复杂边界采空区的漏风渗流的计算，得到与实际流态更接近的流动规律(风 压等值线和流函数线)和采空区漏风强度分布(速度场). 结果表明，迭代算法是振荡性收 敛的，收敛速度快；与Darcy渗流相比，采空区非线性渗流速度场趋向于平缓，在工作面附 近30\,m范围内最大风速降低到原来的0.61倍，其余大部分区域速度略有增加. 迭代方法满 足工程要求.

NON-DARCY SEEPAGE ITERATIVE ALGORITHM FOR CAVING HETEROGENEOUS FLAT FLOW FIELD

To solve the Bachmat nonlinear seepage equation,an iterative algorithm based on the variable permeability Darcy seepage is proposed,considering the goaf characters.Finite element numerical model for nonlinear air leakage flow pattern in caving goaf is established,the flow laws(contours of wind pressure and lines of stream function)and the goaf air leakage intensity distributions(velocity field)are obtained by calculating the air leakage seepage of complex boundary goal,which are found to be consistent with the practical flow patterns.The results indicate that the iterative algorithm converges with oscillation,and the convergence is rapid;in comparison to the Darcy seepage,only the largest wind velocity around the local area near the working face for the nonlinear seepage reduces to 0.61 of the original value,and there is no significant difference in other areas.