报告题目:
Flows in Discrete fracture networks, from fine scale
explicit simulations to network models and reservoir simulators
报告人:Benoit Noetinger
(巴黎中央理工学院化石能源系主任、法国石油研究院“新能源”集团
高级专家、法国巴黎第六大学教授,美国怀俄明州立大学特邀教授)
报告时间:2014年5月14日(周三) 上午 10:00-11:30
报告地点:力学一楼239
组织单位:热科学和能源工程系
Abstract
About 30 % of known hydrocarbon reserves are contained in naturally
fractured formations. Recovery factors may vary considerably, due to
difficulties to get a reliable characterization of the whole set of fracture
positions, shapes and flow properties. Commercial integrated software suites,
like FRACA Flow, provide workflows allowing to build 3D Discrete Fracture
Network (DFN) models using geological, seismic and well data. Additional
modules enable to simulate transient well tests and to facilitate the
fracture properties calibration. As soon as the fracture model is built,
gradual deformations of the DFN may be used to improve the history matching.
A 3D DFN
Connectivity (percolation) effects are emphasized, a flow localization
phenomena (flow through the connected fracture network) can be observed.
This implies an amplified sensitivity to coupled processes (like
geomechanical damage of the conducting fractures etc..). Localization imply
that large uncertainties are to be expected, that increase the risks and
associated exploitation costs. Simulating the dynamic behavior of such
reservoirs, using as much as possible a workflow accounting for both fine
scale data and geological considerations, permits to estimate these risks,
and to improve the final recovery. Dynamic simulations at the field scale
are still based on continuous approaches, due to computing limitations. So,
an up-scaling step remains necessary inside the workflow to capture the DFN
information. The continuous model is generally a set of double porosity/
double permeability equations that captures the dual nature of flows in
fractured reservoirs: the fluid flows to the wells via the fracture network.
The presentation will focus about setting up rigorous workflows allowing to
combine the DFN approach, as well as the associated continuous description.
Open challenges will be discussed.