Отправлено: 20.08.10 02:57. Заголовок: Numerical experiments for the conductive properties of saturated rock

WenZheng Yue and Guo Tao
Numerical experiments for the conductive properties of saturated rock

Science in China Series D: Earth Sciences
Volume 51, Supplement 2, 174-180, DOI: 10.1007/s11430-008-6006-9

Abstract
The reservoir evaluation as a key technology in oil exploration and production is based on the electrical transport property (ETP) of saturated rock that is described in a mathematical form with Arhcie s equation. But there have been increasing cases observed in many researches indicating that the ETP is non-Archie especially for the complex reservoir with low porosity and permeability. In this paper, the numerical experiments based on the Lattice Boltzmann method (LBM) have been employed to study the effect of porous structure and fluids on the ETP for revealing the nature of non-Archie phenomenon in micro-scale. The results of numerical experiments have proved that the saturation exponent n is a function of water saturation and porosity instead of being a constant in Archie’s equation. And then, a new formula has been developed for the EPT through combining the result of numerical simulation with that of laboratory measurements. The calculations from the new formula show very good agreement with laboratory measurements to demonstrate the efficiency of the new formula over the conventional methods in non-Archie rock.
Keywords electrical transport property - non-Archie phenomenon - fluid saturation - porous media - Lattice Boltzmann method

Supported by the National Natural Science Foundation of China (Grant Nos. 50404001 and 50374048), and the National Key Fundamental R&D Project (Grant No. 2007CB209601), also by the China National Petroleum Cooperation Fundamental Research Program (Grant No. 06A30102)


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