How to change elastic modulus every time step in flac3d

#How to change elastic modulus every time step in flac3d verification#
#How to change elastic modulus every time step in flac3d code#

In the former approach, the fractured medium is considered as an equivalent continuum medium whose properties are derived from an appropriate upscaling procedure by using a homogenization technique. Since then, the double permeability system is still used as a common nomination for fractured reservoirs.ДЄlbeit a huge number of studies on fractured rock masses in the past, their modeling is yet a challenging and dynamic research topic, with two principal trends grouping continuum and discontinuum approaches. The idea of dissociation of flow inside the fracture network from that of the matrix is first proposed in. Thus, the presence of fractures induces in the reservoir a quite complex fluid flow and hence significantly affects the production rate of oil recovery or geothermal energy.

Likewise, the hydraulic conductivity of such fractured reservoirs is composed by the conductivity of the rock matrix (pores and their connectivity) and the conductivity of cracks/fractures the later one is usually some orders of magnitude greater than the former. The porosity of the matrix constitutes the primary porosity and the essential storage capacity of the reservoir, while the capacity storage of fractures represents only some fraction of the total porosity. IntroductionД®valuation of effective mechanical and hydraulic properties of a geological reservoir, represented as porous rock masses with complex fracture networks, is a major issue in many engineering applications such as oil and gas field recovery, CO 2 storage, and geothermal exploitation to just mention a few. The numerical simulations show that the dead-end fractures could have a considerable contribution on the effective compliance moduli, while their effect can be neglected to calculate the overall permeability of the of fractured rock masses. However, unlike the previous studies using UDEC, which limits only in the case of fractured rock masses without dead-end fractures, our approach allows accounting for this kind of fractures in the medium.

#How to change elastic modulus every time step in flac3d code#

The comparison of the results calculated from this approach with ones conducted in the literature based on the distinct element code (UDEC) presents a good agreement.

This novel approach was then applied to investigate the effective permeability and elastic compliance tensor of a fractured rock masses taken from a real field, the Sellafield site. An analysis of different parameters notably the influence of the fracture cell size on the precision of the proposed approach was also conducted.

#How to change elastic modulus every time step in flac3d verification#

Through different verification tests, the capability of the developed EFC approach to model the hydromechanical behavior of fractured rock was highlighted. The determination of the hydromechanical properties of the fracture cells as presented in this work allows to provide the theoretical base and to complete some simple approximations introduced in the literature. Each fracture cell in the EFC approach present a continuum porous medium whose hydromechanical properties are calculated from ones of the matrix and ones of the intersected fractures, thanks for using the well-known solution of the joint model. These last elements represent the grid cells intersected by at least one fracture in the medium. As the principal advantage, this approach allows to simplify the meshing procedure by using the simple Cartesian meshes to model the fractures that can be explicitly introduced in the porous medium based on the notion of fracture cells. In this work, the hydromechanical modeling of the fractured rock masses was conducted based on a new numerical simulation method named as embedded fracture continuum (EFC) approach.