source: inundation/ga/storm_surge/pyvolution-parallel/netherlands.py @ 1453

"""Example of shallow water wave equation.

This is called Netherlands because it shows a dam with a gap in it and
stylised housed behind it and below the water surface.

"""

######################
# Module imports
#
from shallow_water import Domain, Reflective_boundary, Dirichlet_boundary,\
     Transmissive_boundary, Constant_height

from mesh_factory import rectangular
from Numeric import array


class Weir:
    """Set a bathymetry for simple weir with a hole.
    x,y are assumed to be in the unit square
    """

    def __init__(self, stage):
        self.inflow_stage = stage

    def __call__(self, x, y):
        from Numeric import zeros, Float

        N = len(x)
        assert N == len(y)

        z = zeros(N, Float)
        for i in range(N):
            z[i] = -x[i]/20  #General slope

            #Flattish bit to the left
            if x[i] <= 0.3:
                #z[i] = -x[i]/5
                z[i] = -x[i]/20


            #Weir
            if x[i] > 0.3 and x[i] < 0.4:
                z[i] = -x[i]/20+1.2

            #Dip
            #if x[i] > 0.6 and x[i] < 0.9:
            #    z[i] = -x[i]/20-0.5  #-y[i]/5

            #Hole in weir
            #if x[i] > 0.3 and x[i] < 0.4 and y[i] > 0.2 and y[i] < 0.4:
            if x[i] > 0.3 and x[i] < 0.4 and y[i] > 0.4 and y[i] < 0.6:
                #z[i] = -x[i]/5
                z[i] = -x[i]/20

            #Poles
            #if x[i] > 0.65 and x[i] < 0.8 and y[i] > 0.55 and y[i] < 0.65 or\
            #       x[i] > 0.75 and x[i] < 0.9 and y[i] > 0.35 and y[i] < 0.45:
            #    z[i] = -x[i]/20+0.4

            if (x[i] - 0.72)**2 + (y[i] - 0.6)**2 < 0.05**2:# or\
                   #x[i] > 0.75 and x[i] < 0.9 and y[i] > 0.35 and y[i] < 0.45:
                z[i] = -x[i]/20+0.4

            #Wall
            if x[i] > 0.995:
                z[i] = -x[i]/20+0.3

        return z/2



######################
# Domain
#


N = 150 #size = 45000
N = 130 #size = 33800
N = 600 #Size = 720000
N = 20

#N = 15

print 'Creating domain'
#Create basic mesh
points, vertices, boundary = rectangular(N, N)

#Create shallow water domain
domain = Domain(points, vertices, boundary)

domain.check_integrity()
domain.default_order = 2
#domain.beta_h=0

#Output params
domain.smooth = False
domain.reduction = min  #Looks a lot better on top of steep slopes

print "Number of triangles = ", len(domain)


if N > 30:
    domain.visualise = False
    domain.checkpoint = False
    domain.store = True    #Store for visualisation purposes
    domain.format = 'sww'   #Native netcdf visualisation format
    import sys, os
    #FIXME: This was os.path.splitext but caused weird filenames based on root
    base = os.path.basename(sys.argv[0])
    domain.filename, _ = os.path.splitext(base)
else:
    domain.visualise = True
    domain.checkpoint = False
    domain.store = False


#Set bed-slope and friction
inflow_stage = 0.08
manning = 0.02
Z = Weir(inflow_stage)

print 'Field values'
domain.set_quantity('elevation', Z)
domain.set_quantity('friction', manning)


######################
# Boundary conditions
#
print 'Boundaries'
Br = Reflective_boundary(domain)
Bt = Transmissive_boundary(domain)

#Constant inflow
Bd = Dirichlet_boundary([2*inflow_stage, 0.0, 0.0])


#Set boundary conditions
domain.set_boundary({'left': Bd, 'right': Br, 'bottom': Br, 'top': Br})


######################
#Initial condition
#
print 'Initial condition'
domain.set_quantity('stage', Constant_height(Z, 0.))

#Evolve
import time
t0 = time.time()

for t in domain.evolve(yieldstep = 0.1, finaltime = 7.0):
    domain.write_time()

print 'That took %.2f seconds' %(time.time()-t0)