Get potential differential — get_potential

Get the cumulative effect of all wells at a singled location, output as head (confined aquifer) or discharge potential (unconfined aquifer).

get_potential_differential(loc, wells, aquifer)

Arguments

loc	coordinates `data.frame` with columns labeled 'x' and 'y', or as vector as c(x,y), with units of [m]
wells	wells object with each row containing rate Q [m^3/s], diam [m], radius of influence R [m], & coordinates x [m], y [m]
aquifer	Afuifer object containing aquifer_type, h0, Ksat, bounds, z0 (for confined case only)

Value

The output is the cumulative effect at loc of all wells on the hydraulic head [units=m] if aquifer_type="confined" or discharge potential [m^2] if aquifer_type="unconfined".

Note: if the loc is contained within the diameter of a well, the distance between the location and that well is automatically adjusted to the edge of the well screen (i.e., well$diam/2). Similar any well-location distance that exceeds the radius of influence of the well, R, is set equal to R

Examples

# Single test locations
aquifer <- define_aquifer(aquifer_type="confined",Ksat=0.00001,h0=0,z0=30)

well1 <- define_wells(x=0,y=0,Q=1e-3,diam=0.75,R=300)
well2 <- define_wells(x=0.5,y=0.25,Q=-2e-3,diam=0.8,R=300)
get_potential_differential(loc=c(50,50),well1,aquifer)
#> [1] 0.7666949
get_potential_differential(loc=c(50,50),well2,aquifer)
#> [1] -1.541374

# Multiple test locations
wells <- data.frame(x=c(-10,10),y=c(-10,10),Q=c(1e-3,-1e-3),diam=c(0.1,0.1),R=c(300,300))
grid_pts <- data.frame(x=c(-11,0,11),y=c(-11,0,11))
aquifer_unconfined <- define_aquifer(aquifer_type="confined",Ksat=0.00001,h0=0,z0=30)
get_potential_differential(grid_pts,wells,aquifer_unconfined)
#> [1]  1.615169  0.000000 -1.615169

get_potential_differential(c(1,1))
#> [1] 0
get_potential_differential(data.frame(x=c(1,1),y=c(2,2)))
#> [1] 0 0