# Groundwater Flow Equation

Used in hydrogeology, the groundwater flow equation is the mathematical relationship which is used to describe the flow of groundwater through an aquifer. The transient flow of groundwater is described by a form of the diffusion equation, similar to that used in heat transfer to describe the flow of heat in a solid (heat conduction). The steady-state flow of groundwater is described by a form of the Laplace equation, which is a form of potential flow and has analogs in numerous fields.

The groundwater flow equation is often derived for a small representative elemental volume (REV), where the properties of the medium are assumed to be effectively constant. A mass balance is done on the water flowing in and out of this small volume, the flux terms in the relationship being expressed in terms of head by using the constituitive equation called Darcy's law, which requires that the flow is slow.

### Other articles related to "groundwater flow equation, groundwater flow, equation, flow, groundwater flow equations":

Hydrogeology - Calculation of Groundwater Flow
... To use the groundwater flow equation to estimate the distribution of hydraulic heads, or the direction and rate of groundwater flow, this partial differential equation (P ... most common means of analytically solving the diffusion equation in the hydrogeology literature are Laplace, Hankel and Fourier transforms (to reduce the number of dimensions of the ... No matter which method we use to solve the groundwater flow equation, we need both initial conditions (heads at time (t) = 0) and boundary conditions (representing either the physical boundaries of the domain, or an ...
MODFLOW - Groundwater Flow Equation - Limitations
... MODFLOW which is designed for density-dependent groundwater flow and transport) The principal components of anisotropy of the hydraulic conductivity used in MODFLOW is displayed on the right ... non-orthogonal anisotropies, as could be expected from flow in fractures ...
Yamabe Flow
... In differential geometry, the Yamabe flow is an intrinsic geometric flow—a process which deforms the metric of a Riemannian manifold ... It is the negative L2-gradient flow of the (normalized) total scalar curvature, restricted to a given conformal class it can be interpreted as deforming a Riemannian metric to a ... It was introduced by Richard Hamilton shortly after the Ricci flow, as an approach to solve the Yamabe problem on manifolds of positive conformal Yamabe invariant ...
Groundwater Flow Equation - Two-dimensional Groundwater Flow
... The above groundwater flow equations are valid for three dimensional flow ... In unconfined aquifers, the solution to the 3D form of the equation is complicated by the presence of a free surface water table boundary condition in addition to ... This is a non-linear problem, even though the governing equation is linear ...
Flow - Other
... Flow (policy debate), a form of note-taking in policy debate Cash flow, the movement of cash into or out of a business, project, or financial product ...

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