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| -rwxr-xr-x | makeBoundaryFile.py | 208 |
1 files changed, 208 insertions, 0 deletions
diff --git a/makeBoundaryFile.py b/makeBoundaryFile.py new file mode 100755 index 0000000..e3d30cb --- /dev/null +++ b/makeBoundaryFile.py @@ -0,0 +1,208 @@ +#!/usr/bin/env python3 + +import matplotlib.pyplot as plt +import numpy as np +import bisect + +with open('./1D_top.txt', "r") as data: + xch, ych, zch = np.loadtxt(data, delimiter=' ', unpack=True) + +# Fit with polyfit +m, c = np.polyfit(ych, zch, 1) +print('gradient =', m, 'intercept =', c) + +slope = abs(m) # slope at top boundary +target_flow = 2.0 # imposed discharge + +with open('../topography/top_boundary.xyz', "r") as topo: + xin, yin, zin = np.loadtxt(topo, delimiter=' ', unpack=True) + +# array index and co-ordinates are related by: +# index = (co-ord - 0.25)*2 +xregion = xin[280:301] +zregion = zin[280:301] + +xregion_west = xin[100:281] +zregion_west = zin[100:281] + +xregion_east = xin[300:408] +zregion_east = zin[300:408] + +#print(zregion) + +zmin = zregion.min() # minimum height +zmax = zregion[-1]-0.01 # overtopping height +zmax_west = zmax +zmax_east = zmax + +zmin_west = zregion_west.min() +zmin_east = zregion_east.min() + +print(zmin_east) + +numH = 50 # number of height intervals +n_co_chan = 0.035 # Manning's coefficient for inland water +n_co_west = 0.040 # Manning's coefficient for general surface +n_co_east = 0.040 # Manning's coefficient for general surface +def conveyance(numH, n_co, xregion, zregion, zmin, zmax): + p_i = [] # wetted perimeter + A_i = [] # area + r_h = [] # hydraulic radius + h_i = [] # list of heights + K_i = [] # conveyance + Q_i = [] # discharge + x_sub = [[] for i in range(numH)] # list of x values in subregion + z_sub = [[] for i in range(numH)] # list of z values in subregion + for i in range(numH): + h_i.append(zmin + (i+1)*(zmax-zmin)/numH) + #print(zregion[zregion < h_i[i]]) + booleanArray = zregion < h_i[i] + #print(booleanArray[i]) + x_sub[i] += list(xregion[booleanArray]) + z_sub[i] += list(zregion[booleanArray]) + for interval in range(len(xregion)-1): + if booleanArray[interval+1] != booleanArray[interval]: + x_extra = xregion[interval] + (h_i[i]-zregion[interval])*(xregion[interval+1]-xregion[interval])/(zregion[interval+1]-zregion[interval]) + bisect.insort(x_sub[i], x_extra) # add intercept value + ind_x = x_sub[i].index(x_extra) + z_sub[i].insert(ind_x, h_i[i]) # add height value + #print(z_sub[i]) + + dp = 0 + dA = 0 + eps = 1e-06 + for j in range(len(x_sub[i])-1): + if abs(z_sub[i][j+1] - h_i[i]) > eps or abs(z_sub[i][j] - h_i[i]) > eps: + dp += np.hypot(x_sub[i][j+1] - x_sub[i][j], + abs(z_sub[i][j+1] - z_sub[i][j])) + #print(dp) + # calculate area using trapezium rule + dA += (h_i[i] - (z_sub[i][j+1] + z_sub[i][j])/2)*(x_sub[i][j+1] - x_sub[i][j]) + #print('Area =', dA) + + p_i.append(dp) + A_i.append(dA) + + r_h.append(A_i[i]/p_i[i]) # ratio of area and wetted perimeter + #print('hydraulic radius =', r_h[i]) + K_i.append(A_i[i]*(1/n_co)*r_h[i]**(2/3)) # conveyance + Q_i.append(K_i[i]*slope**0.5) # discharge + + return p_i, A_i, r_h, h_i, K_i, Q_i + +#print(h_i) + +def plot_region(xdata, labelx, + ydata1, labely1, + ydata2, labely2, + ydata3, labely3, titlep): + plt.xlabel(labelx) + plt.ylabel(labely1) + plt.title(titlep) + plt.plot(xdata, ydata1) + plt.show() + + plt.xlabel(labelx) + plt.ylabel(labely2) + plt.title(titlep) + plt.plot(xdata, ydata2) + plt.show() + + plt.xlabel(labelx) + plt.ylabel(labely3) + plt.title(titlep) + plt.plot(xdata, ydata3) + plt.show() + +p_i, A_i, r_h, h_i, K_i, Q_i = conveyance( + numH, n_co_chan, xregion, zregion,zmin, zmax) + +plot_region(h_i-zmin, 'maximum depth / m', + r_h, 'hydraulic radius / m', + K_i, r'conveyance / $m^3/s$', + Q_i, r'discharge / $m^3/s$', 'main channel flow') + +p_i_west, A_i_west, r_h_west, h_i_west, K_i_west, Q_i_west = conveyance( + numH, n_co_west, xregion_west, zregion_west, zmin_west, zmax_west) + +plot_region(h_i_west-zmin_west, 'maximum depth / m', + r_h_west, 'hydraulic radius / m', + K_i_west, r'conveyance / $m^3/s$', + Q_i_west, r'discharge / $m^3/s$', 'west overland flow') + +p_i_east, A_i_east, r_h_east, h_i_east, K_i_east, Q_i_east = conveyance( + numH, n_co_east, xregion_east, zregion_east, zmin_east, zmax_east) + +plot_region(h_i_east-zmin_east, 'maximum depth / m', + r_h_east, 'hydraulic radius / m', + K_i_east, r'conveyance / $m^3/s$', + Q_i_east, r'discharge / $m^3/s$', 'east overland flow') + +target_flow_west = target_flow - Q_i[-1] - Q_i_east[-1] +# calculate velocity: note dependence on hydraulic radius +velocity_channel = Q_i[-1]/A_i[-1] +velocity_east = Q_i_east[-1]/A_i_east[-1] + +print(target_flow_west) + +# find insertion point for target flow value +ind_q = bisect.bisect(Q_i_west, target_flow_west) +print(ind_q) + +# find height at target flow by linear interpolation +h_extra = h_i_west[ind_q-1] + (h_i_west[ind_q]-h_i_west[ind_q-1])*(target_flow_west-Q_i_west[ind_q-1])/(Q_i_west[ind_q]-Q_i_west[ind_q-1]) +print(h_i_west[ind_q-1], h_extra, h_i_west[ind_q]) +# find area at target flow by linear interpolation +A_extra = A_i_west[ind_q-1] + (h_extra-h_i_west[ind_q-1])*(A_i_west[ind_q]-A_i_west[ind_q-1])/(h_i_west[ind_q]-h_i_west[ind_q-1]) +print(r_h_west[ind_q-1], r_h_west[ind_q]) + +velocity_west = target_flow_west/A_extra +print(velocity_channel, velocity_east, velocity_west) + +dX = (xin[0]+xin[-1])/len(xin) # cell size +print('dX =', dX) +csa = np.zeros(len(xin)) # cross-sectional area +csa_west = 0 +csa_chan = 0 +csa_east = 0 +for index, xitem in enumerate(xin): + if xitem < xin[280]: + csa[index] = max(0, (h_extra - zin[index])*dX) + csa_west += csa[index] + elif xitem < xin[301]: + csa[index] = max(0, (zmax - zin[index])*dX) + csa_chan += csa[index] + else: + csa[index] = max(0, (zmax_east - zin[index])*dX) + csa_east += csa[index] + +#print('csa_west = {} csa_chan = {} csa_east = {}'.format(csa_west, csa_chan, csa_east)) +#print('A_i_west = {} A_i = {} A_i_east = {}'.format(A_extra, A_i[-1], A_i_east[-1])) + +def save_bc(): + with open('BCTop.txt', 'w') as f: + f.write('{:6} {:>2} {:>2} {:>10}\n'.format('#x', 'c', 'q', 'h')) + for ind_z, (xitem, zitem) in enumerate(zip(xin, zin)): + if csa[ind_z] == 0: + # wall boundary condition + f.write('{:6.2f} {:>2}\n'.format(xitem, 2)) + elif xitem < xin[280]: + # imposed discharge on western side + f.write('{:6.2f} {:>2} {:10.6f} {:9.6f}\n'.format( + xitem, 5, + -csa[ind_z]*target_flow_west/csa_west, + h_extra-zitem)) + elif xitem < xin[301]: + # imposed discharge within channel + f.write('{:6.2f} {:>2} {:10.6f} {:9.6f}\n'.format( + xitem, 5, + -csa[ind_z]*Q_i[-1]/csa_chan, + zmax-zitem)) + else: + # imposed discharge on eastern side + f.write('{:6.2f} {:>2} {:10.6f} {:9.6f}\n'.format( + xitem, 5, + -csa[ind_z]*Q_i_east[-1]/csa_west, + zmax_east-zitem)) + +save_bc() |