A fissured aquifer model used in petroleum engineering has been studied by the author. It is found that thefissure-induced inhomogeneity which appeared in reservoir media can be expressed by a delay timeτ whichcharac...A fissured aquifer model used in petroleum engineering has been studied by the author. It is found that thefissure-induced inhomogeneity which appeared in reservoir media can be expressed by a delay timeτ whichcharacterizes the process of transition from unsteady to steady seepage flow. Comparison between the fissured aquifer model mentioned above and corresponding homogeneous media is given in this paper. The expression of the characteristic delay timeτis independently derived by using the fissured porous media modeland by solving the characteristic time of an one-dimensioned diffusion equation in turn. The result shows thatthe τ value is in direct proportion to L2. L is the average size of aquifer rock blocks cut by fissures network.The larger the L value, the longer the fissures is and the less the density of fissure is. For identifying the inhomogeneity manifestation of aquifer, a criterion related with the characteristic time of external force action isproposed. In addition, a suggestion on the in-situ measurement of the new aquifer parameter, the 1 value, isgiven.展开更多
文摘A fissured aquifer model used in petroleum engineering has been studied by the author. It is found that thefissure-induced inhomogeneity which appeared in reservoir media can be expressed by a delay timeτ whichcharacterizes the process of transition from unsteady to steady seepage flow. Comparison between the fissured aquifer model mentioned above and corresponding homogeneous media is given in this paper. The expression of the characteristic delay timeτis independently derived by using the fissured porous media modeland by solving the characteristic time of an one-dimensioned diffusion equation in turn. The result shows thatthe τ value is in direct proportion to L2. L is the average size of aquifer rock blocks cut by fissures network.The larger the L value, the longer the fissures is and the less the density of fissure is. For identifying the inhomogeneity manifestation of aquifer, a criterion related with the characteristic time of external force action isproposed. In addition, a suggestion on the in-situ measurement of the new aquifer parameter, the 1 value, isgiven.