Analytical Solution for Darcy Flow in a Bounded Fracture-Matrix Domain

We derive an analytical solution to a Darcy flow problem in a discrete 1D fracture coupled to a 2D continuum matrix. Separate unknowns for the fracture and matrix domain are considered, coupled by a Robin-type condition. The solution, in the form of a Fourier series, applies to a wide range of problem parameters, covering both conductive and barrier fracture cases. The evaluation procedure and convergence properties are discussed. To validate the solution, we compare it against a numerical solution using second-order finite differences in a parametric study. Our results demonstrate the accuracy and effectiveness of the analytical solution, making it a valuable tool for testing numerical schemes for discrete fracture-matrix models.