Perturbation boundary element method for heterogeneous reservoirs; Part 2: Transient-flow problems

This paper discusses the extension of the perturbation boundary element method (BEM) described in the companion paper (Part 1) to transient-flow problems with permeability and porosity variations. The perturbation BEM formulated in Laplace space is verified against simplified heterogeneous problems and is used to generate type curves for idealized heterogeneities. The authors observed that if the average property value in a drainage area was not much different from the near-well property value, heterogeneity had little effect on pressure responses.