Model setup XBeach 2D#

Setup a 2D XBeach model with the Python toolbox

[1]:

# import default modules
import numpy as np
from scipy import interpolate
import matplotlib.pyplot as plt
from mpl_toolkits.mplot3d import axes3d, Axes3D
from matplotlib import cm
import sys
import os

# method to import xbtools with try routine
try:
    import xbTools
except ImportError:
    print('**no xbTools installation found in environment, adding parent path of notebook to see if it works')
    sys.path.append(os.path.abspath(os.path.join('..', '..', 'xbeach-toolbox')))

c:\Users\ridde_mo\AppData\Local\anaconda3\envs\py38\lib\site-packages\scipy\__init__.py:146: UserWarning: A NumPy version >=1.16.5 and <1.23.0 is required for this version of SciPy (detected version 1.23.5
  warnings.warn(f"A NumPy version >={np_minversion} and <{np_maxversion}"

**no xbTools installation found in environment, adding parent path of notebook to see if it works

Import the toolbox.

[2]:

## import specific tools from xbTools
from xbTools.grid.creation import xgrid, ygrid
from xbTools.grid.extension import seaward_extend, lateral_extend
from xbTools.xbeachtools import XBeachModelSetup
from xbTools.general import wave_functions, visualize_mesh

Data#

Load and plot the bathymetry data

[3]:

## load data
bathy = np.loadtxt('..//examples//data//input//bathy.dep')

## set bathy grid
nx = 124
ny = 72
dx = 5
dy = 20

x = np.linspace(0,(nx-1)*dx,nx)
y = np.linspace(0,(ny-1)*dy,ny)

X, Y = np.meshgrid(x,y)

## plot
plt.figure()
plt.pcolor(x,y,bathy)
plt.colorbar()
plt.xlabel('x [m]')
plt.ylabel('y [m]')
plt.title('default bathy')
plt.axis('scaled')

fig     = plt.figure()
ax      = Axes3D(fig)
surf    = ax.plot_surface(X, Y, bathy, cmap=cm.coolwarm,  linewidth=0, antialiased=False)
plt.xlabel('x [m]')
plt.ylabel('y [m]')

C:\Users\ridde_mo\AppData\Local\Temp/ipykernel_22540/3489134793.py:25: MatplotlibDeprecationWarning: Axes3D(fig) adding itself to the figure is deprecated since 3.4. Pass the keyword argument auto_add_to_figure=False and use fig.add_axes(ax) to suppress this warning. The default value of auto_add_to_figure will change to False in mpl3.5 and True values will no longer work in 3.6.  This is consistent with other Axes classes.
  ax      = Axes3D(fig)

[3]:

Text(0.5, 0, 'y [m]')

Create x-grid#

Create spatially varying x-grid resolution.

Note that the following settings can be specified:

xgrid(x,z, ppwl=20, dxmin=5, dxmax=np.inf, vardx=1, wl = 0, eps = 0.01, Tm = 8, xdry=None, zdry=None, dxdry = None, depthfac = 2, maxfac = 1.15, nonh = False)

[4]:

xgr,zgr = xgrid(x, bathy[20,:],dxmin=2)


plt.figure()
plt.plot(x,bathy[20,:],'-o')
plt.plot(xgr,zgr,'.-')
plt.legend(['Bathy','xgr'])
plt.xlabel('x [m]')
plt.ylabel('z [m]')
plt.grid('on')

Create y-grid#

Create spatially varying y-grid resolution.

ygrid has the following default settings:

ygrid(y, dymin = 5, dymax = 20, area_type='center', maxerror = 0.05, transition_distance = -0.1, area_size = 0.4):

[5]:

ygr = ygrid(y)

plt.figure()
plt.plot(y[:-1],np.diff(y),'-o')
plt.plot(ygr[:-1],np.diff(ygr),'.-')
plt.legend(['y','ygr'])
plt.xlabel('y [m]')
plt.ylabel('dy [m]')

Enable optimization of transition distance
Area type center
Transition 142.0

c:\Users\ridde_mo\repos\xbeach-toolbox\xbTools\grid\creation.py:339: RuntimeWarning: overflow encountered in power
  Lj[1] = cell1 * np.sum(np.power(fj[1],np.arange(1,ni+1,1)) )
c:\Users\ridde_mo\repos\xbeach-toolbox\xbTools\grid\creation.py:340: RuntimeWarning: overflow encountered in double_scalars
  Lj[2] = cell1 * np.sum(np.power(np.mean(fj),np.arange(1,ni+1,1)) )
c:\Users\ridde_mo\repos\xbeach-toolbox\xbTools\grid\creation.py:340: RuntimeWarning: overflow encountered in power
  Lj[2] = cell1 * np.sum(np.power(np.mean(fj),np.arange(1,ni+1,1)) )
c:\Users\ridde_mo\repos\xbeach-toolbox\xbTools\grid\creation.py:330: RuntimeWarning: overflow encountered in double_scalars
  fj[1] = 1.1 * fj[1]

[5]:

Text(0, 0.5, 'dy [m]')

Interpolate#

Interpolate data to new grid

[6]:

f = interpolate.interp2d(x, y, bathy, kind='linear')

zgr = f(xgr,ygr)

plt.figure()
plt.pcolor(xgr,ygr,zgr)
plt.xlabel('x [m]')
plt.ylabel('y [m]')
plt.axis('scaled')
plt.title('xgr, ygr bathy')

xgr, ygr = np.meshgrid(xgr,ygr)

Seaward extend#

Extend the grid to the required offshore depth. In this case 20 m with a artifial slope of 1/20.

If desired the function offshore_depth can also be used to determine the required offshore water depth.

[7]:

d_start, slope, Hm0_shoal = wave_functions.offshore_depth(Hm0=9, Tp=15, depth_offshore_profile=abs(bathy[0,0]), depth_boundary_conditions=20)

xgr, ygr, zgr = seaward_extend(xgr,ygr,zgr,slope=1/20,depth=-20)

plt.figure()
plt.pcolor(xgr,ygr,zgr)
plt.axis('scaled')
plt.xlabel('x [m]')
plt.ylabel('y [m]')
plt.title('seaward extended 2D grid')

plt.figure()
plt.plot(xgr[:,:].T,zgr[:,:].T)
plt.xlabel('x [m]')
plt.ylabel('z [m]')

no convergence
Artificial slope of 1:10
Hm0,shoal = 9.008451731585167
d start = 19.977837324773713
Hm0,shoal/d profile = 1.451507604860271
Hm0,shoal/d slope = 0.45092226876900976
n profile = 0.5248467628414396
n slope = 0.7776515191101054

[7]:

Text(0, 0.5, 'z [m]')

Lateral extend#

Extend the grid lateral with 5 rows

[8]:

xgr,ygr,zgr = lateral_extend(xgr,ygr,zgr,n=5)

plt.figure()
plt.pcolor(xgr,ygr,zgr)
plt.axis('scaled')
plt.xlabel('x [m]')
plt.ylabel('y [m]')
plt.title('lateral extended 2D grid')

[8]:

Text(0.5, 1.0, 'lateral extended 2D grid')

Create model setup#

Create the model setup class

[9]:

xb_setup = XBeachModelSetup('Test simulation')

xb_setup.set_grid(xgr, ygr, zgr, posdwn=-1, alfa=10)
xb_setup.set_nebed(np.ones_like(zgr))
xb_setup.set_friction(np.ones_like(zgr))

xb_setup.set_waves('jonstable',    {'Hm0'       :   [1.5, 2, 1.5],
                                    'Tp'        :   [4, 5, 4],
                                    'gammajsp'  :   [3.3, 3.3, 3.3],
                                    's'         :   [20, 20, 20],
                                    'mainang'   :   [270, 280, 290],
                                    'duration'  :   [3600, 3600, 3600],
                                    'dtbc'      :   [1,1,1]})

xb_setup.set_params({'Wavemodel'    :   'surfbeat',
                     'morphology'   :   0,
                     'befriccoef'   :   0.01,
                     'tstop'        :   3600,
                     'zs0'          :   0,
                     'nglobalvar'   :   ['zb', 'zs', 'H'],
                     'npointvar'    :   ['zs', 'H'],
                     'nmeanvar'     :   ['zb'],
                     'npoints'      :   ['1 0', '6 0', '10 0', '12 0']})

sim_path = os.path.join('xb-2D')
if not os.path.exists(sim_path):
    os.mkdir(sim_path)
xb_setup.write_model(os.path.join(sim_path))

Write grid to shapefile#

Create a shapefile.

[10]:

visualize_mesh.write_mesh_to_shp(xgr, ygr, os.path.join('xb-2D','shape/grid.shp'),0)

xb-2D\shape/grid.shp is saved

[ ]: