Problem 57532. Compute steady drawdown in a confined aquifer
A well extracting water from a confined aquifer will lower the piezometric head and create a cone of depression. In steady state, if the distance r to the point where the drawdown is wanted is smaller than the radius of influence R, then the drawdown s of a well pumping at rate in a confined aquifer of transmissivity T is
If the distance r is greater than the radius of influence, then the drawdown is zero. If multiple wells are pumping, the drawdown at the requested point is the sum of the drawdowns from the individual wells.
Boundaries, such as no-flow and constant-head boundaries, can be modeled using the method of images, as described in Cody Problem 57497. Each real well will have a corresponding image, and the drawdown will be the sum of the drawdowns from all wells—real and image. Recall from the previous problem that for no-flow boundaries, the image wells pump in the same sense as the real wells, whereas for constant-head boundaries, the image wells pump in the opposite sense as the real wells.
Write a function to compute steady-state drawdown in a confined aquifer. Input to the function will be the x- and y-coordinates of the points where drawdown is requested, the x- and y-coordinates of the real wells, the pumping rates and radii of influence of the wells, and the transmissivity of the aquifer. If a boundary is present, it will be specified by two pairs of x- and y-coordinates as well as a character string (‘NF’ for no-flow, ‘CH’ for constant-head).
Solution CommentsShow comments
Problem Recent Solvers2