source: inundation/ga/storm_surge/pyvolution/netherlands.py @ 333

"""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, Time_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 = 250
#N= 8
N = 16
#N = 4
#N = 102
N = 25
N = 16
N = 60
N = 150 #size = 45000
N = 130 #size = 33800
#N = 60
#N = 40
N = 260
#N = 150
N = 264

N = 600 #Size = 720000
N = 220
N = 55


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

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


if N > 50:
    domain.visualise = False
    domain.checkpoint = False
    domain.store = True    #Store for visualisation purposes
    domain.format = 'sww'   #Native netcdf visualisation format
    import sys, os
    root, ext = os.path.splitext(sys.argv[0])
    if domain.smooth is True:
        s = 'smooth'
    else:
        s = 'nonsmooth'        
    domain.filename = root + '_' + s
else:
    domain.visualise = True
    domain.checkpoint = False
    domain.store = False    

    
#Set bed-slope and friction
inflow_stage = 0.08
manning = 0.0
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])


#Time dependent inflow
from math import sin, pi, exp
Bw = Time_boundary(domain=domain,
                   f=lambda t: [0.7*(1 + sin(t*pi/2.5))*\
                                (inflow_stage*(sin(t*pi)+0.7)),0,0])

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

                  

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

#Evolve
import time
t0 = time.time()

for t in domain.evolve(yieldstep = 0.01, finaltime = 1.0):
    domain.write_time()
    
print 'That took %.2f seconds' %(time.time()-t0)