A multi-scale and multi-medium numerical model of a multi-fractured horizontal well in tight oil reservoir of daqing oil field

Abstract

The macroscopic geological conditions and microscopic pore characteristics of tight oil reservoirs are always complex. A multi-medium and multi-scale numerical model which can best embody tight oil reservoir features for a multi–fractured horizontal well (MFHW) is hard to establish. Without a reasonable numerical model, the evaluation and adjustment of a MFHW in a tight oil reservoir are difficult to fulfil. Based on the experiment results, geological data and construction parameters of the Pu34 well area, this paper establishes a multi-scale and multi-medium numerical model of a MFHW, Well X, in Daqing Oil Field and simulates the development effect of Well X after refracturing measurement. The results show that three types of reservoirs and four kinds of pore media exist in the Pu 34 area. The history match shows the numerical model works well. By using this numerical model, the Well X, after re-fracturing, would perform better than without re-fracturing in the early stage of production period, and it also increases the cumulative oil production by 223t after production of 10 years. In economy regard, it has faster oil recovery rate which is helpful for company to recover the investment cost of this well.