1 | """Example of shallow water wave equation analytical solution |
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2 | consists of a symmetrical converging channel with friction and bed slope. |
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3 | |
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4 | Specific methods pertaining to the 2D shallow water equation |
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5 | are imported from shallow_water |
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6 | for use with the generic finite volume framework |
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7 | |
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8 | Copyright 2004 |
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9 | Christopher Zoppou, Stephen Roberts, Ole Nielsen, Duncan Gray |
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10 | Geoscience Australia, ANU |
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11 | |
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12 | Specific methods pertaining to the 2D shallow water equation |
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13 | are imported from shallow_water |
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14 | for use with the generic finite volume framework |
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15 | |
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16 | Conserved quantities are h, uh and vh stored as elements 0, 1 and 2 in the |
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17 | numerical vector named conserved_quantities. |
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18 | """ |
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19 | |
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20 | #----------------------------- |
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21 | # Module imports |
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22 | import sys, string |
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23 | from os import sep |
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24 | sys.path.append('..'+sep+'pyvolution') |
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25 | |
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26 | from shallow_water import Transmissive_boundary, Reflective_boundary, \ |
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27 | Dirichlet_boundary |
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28 | from shallow_water import Domain |
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29 | from pmesh2domain import pmesh_to_domain_instance |
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30 | from Numeric import zeros, Float |
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31 | |
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32 | |
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33 | #------------------------------ |
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34 | # Domain |
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35 | filename = 'MacDonald_77541.tsh' |
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36 | print 'Creating domain from', filename |
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37 | domain = pmesh_to_domain_instance(filename, Domain) |
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38 | print 'Number of triangles = ', len(domain) |
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39 | |
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40 | domain.default_order = 1 |
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41 | domain.smooth = True |
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42 | |
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43 | #------------------------------------- |
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44 | # Provide file name for storing output |
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45 | domain.store = True #Store for visualisation purposes |
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46 | domain.format = 'sww' #Native netcdf visualisation format |
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47 | domain.set_name('MacDonald_77541') |
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48 | |
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49 | #------------- |
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50 | #Bed Elevation |
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51 | fid = open('MacDonald_bed.xya') |
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52 | lines = fid.readlines() |
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53 | n_bed = len(lines) |
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54 | z_bed = zeros(n_bed, Float) |
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55 | x_bed = zeros(n_bed, Float) |
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56 | |
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57 | for line in range(n_bed): |
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58 | value = string.split(lines[line]) |
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59 | x_bed[line] = float(value[0]) |
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60 | z_bed[line] = float(value[1]) |
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61 | |
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62 | #----------------- |
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63 | #Set bed-elevation |
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64 | def x_slope(x,y): |
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65 | n = x.shape[0] |
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66 | z = 0*x |
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67 | for i in range(n): |
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68 | for j in range(n_bed-1): |
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69 | if x[i] >= x_bed[j] and x[i] < x_bed[j+1]: |
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70 | z[i] = z_bed[j] + (z_bed[j+1] - z_bed[j])/(x_bed[j+1] - x_bed[j])*(x[i] - x_bed[j]) |
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71 | return z |
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72 | |
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73 | domain.set_quantity('elevation', x_slope) |
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74 | |
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75 | #--------------------------------------------------------- |
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76 | #Decide which quantities are to be stored at each timestep |
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77 | domain.quantities_to_be_stored = ['stage', 'xmomentum', 'ymomentum'] |
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78 | |
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79 | #Reduction operation for get_vertex_values |
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80 | from anuga.pyvolution.util import mean |
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81 | domain.reduction = mean |
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82 | |
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83 | #-------------------- |
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84 | # Boundary Conditions |
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85 | upstream_depth = 5.035 - 4.393 |
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86 | downstream_depth = 1.5 - 0 |
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87 | discharge = 20 |
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88 | tags = {} |
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89 | tags['Upstream'] = Dirichlet_boundary([upstream_depth, 2, 0.0]) |
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90 | tags['external'] = Reflective_boundary(domain) |
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91 | tags['Downstream'] = Dirichlet_boundary([downstream_depth, 2, 0.0]) |
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92 | domain.set_boundary(tags) |
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93 | |
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94 | #--------- |
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95 | # friction |
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96 | domain.set_quantity('friction', 0.02) |
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97 | |
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98 | #----------------- |
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99 | #Initial condition |
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100 | domain.set_quantity('elevation', 0.0) |
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101 | domain.set_quantity('stage', 0.2) |
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102 | |
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103 | #----------------- |
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104 | #Evolution |
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105 | import time |
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106 | t0 = time.time() |
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107 | for t in domain.evolve(yieldstep = 5, finaltime = 500): |
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108 | domain.write_time() |
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109 | |
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110 | print 'That took %.2f seconds' %(time.time()-t0) |
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111 | |
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112 | |
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