def ainslie_full(nj, ni, h, k, u0=8.5, ct=ct_v90(u0), i0=8.0):
    star = time()
    nj += 1
    ni += 1
    Dmi = ct - 0.05 - (16.0 * ct - 0.5) * i0 / 1000.0

    u = [[0.0 for _ in range(ni)]]
    v = [[0.0 for _ in range(ni)] for _ in range(nj)]

    for g in range(ni):
        u[0][g] = u0 * (1.0 - Dmi * exp(- 3.56 * float(g * h) ** 2.0 / b(Dmi, ct) ** 2.0))

    for j in range(1, nj):
        # start = time()
        A = []
        B = []
        C = []
        R = []

        i = 0

        A.append(- k * E(j * k, u[j-1][i], (u0 - u[j-1][i]) / u0, u0, i0, ct))
        B.append(2.0 * (h ** 2.0 * u[j-1][i] + k * E(j * k, u[j-1][i], (u0 - u[j-1][i]) / u0, u0, i0, ct)))
        C.append(- k * E(j * k, u[j-1][i], (u0 - u[j-1][i]) / u0, u0, i0, ct))
        R.append(k * E(j * k, u[j-1][i], (u0 - u[j-1][i]) / u0, u0, i0, ct) * (2.0 * u[j-1][i+1] - 2.0 * u[j-1][i]) + 2.0 * h ** 2.0 * u[j-1][i] ** 2.0)

        for i in range(1, ni):

            #  Uncomment if v is not neglected. Radial velocity.
            if j == 1:
                v[j][i] = (i * h) / ((i * h) + h) * (v[j-1][i-1] - h / k * (u[j-1][i] - u[0][i]))
            elif j > 1:
                v[j][i] = (i * h) / ((i * h) + h) * (v[j-1][i-1] - h / k * (u[j-1][i] - u[j-2][i]))

            A.append(k * (h * E(j * k, u[j-1][i], (u0 - u[j-1][i]) / u0, u0, i0, ct) - (i * h) * h * v[j][i] - 2.0 * (i * h) * E(j * k, u[j-1][i], (u0 - u[j-1][i]) / u0, u0, i0, ct)))
            B.append(4.0 * (i * h) * (h ** 2.0 * u[j-1][i] + k * E(j * k, u[j-1][i], (u0 - u[j-1][i]) / u0, u0, i0, ct)))
            C.append(k * ((i * h) * h * v[j][i] - 2.0 * (i * h) * E(j * k, u[j-1][i], (u0 - u[j-1][i]) / u0, u0, i0, ct) - h * E(j * k, u[j-1][i], (u0 - u[j-1][i]) / u0, u0, i0, ct)))
            if i < ni - 1:
                R.append(h * k * E(j * k, u[j-1][i], (u0 - u[j-1][i]) / u0, u0, i0, ct) * (u[j-1][i+1] - u[j-1][i-1]) + 2.0 * k * E(j * k, u[j-1][i], (u0 - u[j-1][i]) / u0, u0, i0, ct) * (i * h) * (u[j-1][i+1] - 2.0 * u[j-1][i] + u[j-1][i-1]) - (i * h) * h * k * v[j-1][i] * (u[j-1][i+1] - u[j-1][i-1]) + 4.0 * (i * h) * h ** 2.0 * u[j-1][i] ** 2.0)
            elif i == ni - 1:
                R.append(h * k * E(j * k, u[j-1][i], (u0 - u[j-1][i]) / u0, u0, i0, ct) * (u0 - u[j-1][i-1]) + 2.0 * k * E(j * k, u[j-1][i], (u0 - u[j-1][i]) / u0, u0, i0, ct) * (i * h) * (u0 - 2.0 * u[j-1][i] + u[j-1][i-1]) - (i * h) * h * k * v[j-1][i] * (u0 - u[j-1][i-1]) + 4.0 * (i * h) * h ** 2.0 * u[j-1][i] ** 2.0)

        # print time() - start

        C[0] += A[0]
        del A[0]
        R[-1] -= C[-1] * u0
        del C[-1]
        # start3 = time()
        u.append(thomas(A, B, C, R))
        # print time() - start3
    print time() - star,
    print 's'
    print u[-1][0]
    return u
def ainslie(ct, u0, distance_parallel, distance_perpendicular, I0):

    # centreline = open('centreline.dat', 'w')
    # velocity = open('velocity.dat', 'w')

    h = 0.01
    L = distance_parallel
    n = int(L / h) + 1
    Uc1 = [0.0 for _ in range(n)]
    d1 = [0.0 for _ in range(n)]
    Ct = ct  # Thrust coefficient
    U0 = u0
    # dr = 0.1
    Y = distance_perpendicular
    # m = int(Y / dr)

    Dmi = Ct - 0.05 - (16.0 * Ct - 0.5) * I0 / 10.0

    # print Dmi, "Dmi"
    Uc1[0] = U0 * (1.0 - Dmi)  # Boundary condition at x = 2.0
    # print U0, U0 * (1.0 - Dmi)
    # print Uc1[0], "Uci[0]"
    d1[0] = Dmi
    # print d1[0], "d1[0]"
    for i in range(
            1, n
    ):  # For all positions in the wake centreline direction. Recursive. Whole grid
        Uc1[i] = Uc1[i - 1] + (h * 16.0 *
                               E(i * h, Uc1[i - 1], d1[i - 1], U0, I0, Ct) *
                               (Uc1[i - 1]**3.0 - U0 * Uc1[i - 1]**2.0 -
                                Uc1[i - 1] * U0**2.0 + U0**3.0) /
                               (Uc1[i - 1] * Ct * U0**2.0))
        d1[i] = 1.0 - Uc1[i] / U0
    # Code to calculate wake deficit at a specific point instead of the whole grid. Namely, the rotor's centrepoint.
    # print "final"
    return d1[-1] * exp(-3.56 * (Y / b(d1[-1], ct))**2.0) * (
        1.0 + 7.12 * (0.07 * distance_parallel / b(d1[-1], ct)))**(-0.5)
def ainslie(ct, u0, distance_parallel, distance_perpendicular, I0):

    # centreline = open('centreline.dat', 'w')
    # velocity = open('velocity.dat', 'w')

    h = 0.01
    L = distance_parallel - 2.0
    n = int(L / h) + 1
    Uc1 = [0.0 for _ in range(n)]
    d1 = [0.0 for _ in range(n)]
    karman = 0.41  # von Karman constant
    Ct = ct  # Thrust coefficient
    U0 = u0
    # dr = 0.1
    Y = distance_perpendicular
    # m = int(Y / dr)

    Dmi = Ct - 0.05 - (16.0 * Ct - 0.5) * I0 / 1000.0

    def b(deficit):  # Wake width measure
        return (3.56 * Ct / (8.0 * deficit * (1.0 - 0.5 * deficit))) ** 0.5

    def F(x):  # Factor for near and far wake
        if x >= 5.5:
            return 1.0
        if x < 5.5:
            if x >= 4.5:
                return 0.65 + ((x - 4.5) / 23.32) ** (1.0 / 3.0)
            else:
                return 0.65 - ((- x + 4.5) / 23.32) ** (1.0 / 3.0)

    def E(x1, Uf, Ud, Dm):  # Eddy viscosity term
        epsilon = F(x1) * (0.015 * b(Dm) * (Uf - Ud) + (karman ** 2.0) * I0 / 100.0)
        print epsilon
        return epsilon

    Uc1[0] = U0 * (1.0 - Dmi)  # Boundary condition at x = 2.0
    d1[0] = Dmi
    for i in range(1, n):  # For all positions in the wake centreline direction. Recursive. Whole grid
        Uc1[i] = Uc1[i - 1] + (h * 16.0 * E(i * h, U0, Uc1[i - 1], d1[i - 1]) * (Uc1[i - 1] ** 3.0 - U0 * Uc1[i - 1] ** 2.0 - Uc1[i - 1] * U0 ** 2.0 + U0 ** 3.0) / (Uc1[i - 1] * Ct * U0 ** 2.0))
        d1[i] = 1.0 - Uc1[i] / U0

    ########### Code to calculate wake deficit at a specific point instead of the whole grid. Namely, the rotor's centrepoint.

    return d1[-1] * exp(- 3.56 * (Y / b(d1[-1])) ** 2.0) * (1.0 + 7.12 * (0.07 * distance_parallel / b(d1[-1]))) ** (- 0.5)
示例#4
0
def ainslie_full(nj, ni, h, k, u0=8.5, ct=ct_v90(u0), i0=8.0):
    star = time()
    nj += 1
    ni += 1
    Dmi = ct - 0.05 - (16.0 * ct - 0.5) * i0 / 1000.0

    u = [[0.0 for _ in range(ni)]]
    v = [[0.0 for _ in range(ni)] for _ in range(nj)]

    for g in range(ni):
        u[0][g] = u0 * (1.0 -
                        Dmi * exp(-3.56 * float(g * h)**2.0 / b(Dmi, ct)**2.0))

    for j in range(1, nj):
        # start = time()
        A = []
        B = []
        C = []
        R = []

        i = 0

        A.append(-k * E(j * k, u[j - 1][i],
                        (u0 - u[j - 1][i]) / u0, u0, i0, ct))
        B.append(2.0 * (h**2.0 * u[j - 1][i] +
                        k * E(j * k, u[j - 1][i],
                              (u0 - u[j - 1][i]) / u0, u0, i0, ct)))
        C.append(-k * E(j * k, u[j - 1][i],
                        (u0 - u[j - 1][i]) / u0, u0, i0, ct))
        R.append(k *
                 E(j * k, u[j - 1][i], (u0 - u[j - 1][i]) / u0, u0, i0, ct) *
                 (2.0 * u[j - 1][i + 1] - 2.0 * u[j - 1][i]) +
                 2.0 * h**2.0 * u[j - 1][i]**2.0)

        for i in range(1, ni):

            #  Uncomment if v is not neglected. Radial velocity.
            if j == 1:
                v[j][i] = (i * h) / ((i * h) + h) * (v[j - 1][i - 1] - h / k *
                                                     (u[j - 1][i] - u[0][i]))
            elif j > 1:
                v[j][i] = (i * h) / (
                    (i * h) + h) * (v[j - 1][i - 1] - h / k *
                                    (u[j - 1][i] - u[j - 2][i]))

            A.append(k * (h * E(j * k, u[j - 1][i],
                                (u0 - u[j - 1][i]) / u0, u0, i0, ct) -
                          (i * h) * h * v[j][i] - 2.0 *
                          (i * h) * E(j * k, u[j - 1][i],
                                      (u0 - u[j - 1][i]) / u0, u0, i0, ct)))
            B.append(4.0 * (i * h) *
                     (h**2.0 * u[j - 1][i] +
                      k * E(j * k, u[j - 1][i],
                            (u0 - u[j - 1][i]) / u0, u0, i0, ct)))
            C.append(k * ((i * h) * h * v[j][i] - 2.0 *
                          (i * h) * E(j * k, u[j - 1][i],
                                      (u0 - u[j - 1][i]) / u0, u0, i0, ct) -
                          h * E(j * k, u[j - 1][i],
                                (u0 - u[j - 1][i]) / u0, u0, i0, ct)))
            if i < ni - 1:
                R.append(
                    h * k * E(j * k, u[j - 1][i],
                              (u0 - u[j - 1][i]) / u0, u0, i0, ct) *
                    (u[j - 1][i + 1] - u[j - 1][i - 1]) +
                    2.0 * k * E(j * k, u[j - 1][i],
                                (u0 - u[j - 1][i]) / u0, u0, i0, ct) *
                    (i * h) *
                    (u[j - 1][i + 1] - 2.0 * u[j - 1][i] + u[j - 1][i - 1]) -
                    (i * h) * h * k * v[j - 1][i] *
                    (u[j - 1][i + 1] - u[j - 1][i - 1]) + 4.0 *
                    (i * h) * h**2.0 * u[j - 1][i]**2.0)
            elif i == ni - 1:
                R.append(h * k * E(j * k, u[j - 1][i],
                                   (u0 - u[j - 1][i]) / u0, u0, i0, ct) *
                         (u0 - u[j - 1][i - 1]) +
                         2.0 * k * E(j * k, u[j - 1][i],
                                     (u0 - u[j - 1][i]) / u0, u0, i0, ct) *
                         (i * h) * (u0 - 2.0 * u[j - 1][i] + u[j - 1][i - 1]) -
                         (i * h) * h * k * v[j - 1][i] *
                         (u0 - u[j - 1][i - 1]) + 4.0 *
                         (i * h) * h**2.0 * u[j - 1][i]**2.0)

        # print time() - start

        C[0] += A[0]
        del A[0]
        R[-1] -= C[-1] * u0
        del C[-1]
        # start3 = time()
        u.append(thomas(A, B, C, R))
        # print time() - start3
    print time() - star,
    print 's'
    print u[-1][0]
    return u
def ainslie_full(ct, u0, distance_parallel, distance_perpendicular, i0):
    # centreline = open('centreline.dat', 'w')
    # velocity = open('velocity.dat', 'w')

    di = 2.0
    dj = distance_parallel - 2.0
    # ni = int(di * 80)
    # nj = int(dj * 80)
    ni = nj = 100
    k = dj / float(nj)
    h = di / float(ni)

    nj += 1
    ni += 1
    Dmi = ct - 0.05 - (16.0 * ct - 0.5) * i0 / 1000.0

    u = [0.0 for _ in range(ni)]
    v = [0.0 for _ in range(ni)]

    for g in range(ni):
        u[g] = u0 * (1.0 - Dmi * exp(- 3.56 * float(g * h) ** 2.0 / b(Dmi, ct) ** 2.0))

    old_u = u
    u_initial = u
    old_v = v

    for j in range(1, nj):
        # start = time()
        A = []
        B = []
        C = []
        R = []

        i = 0

        A.append(- k * E(j * k, old_u[i], (u0 - old_u[i]) / u0, u0, i0, ct))
        B.append(2.0 * (h ** 2.0 * old_u[i] + k * E(j * k, old_u[i], (u0 - old_u[i]) / u0, u0, i0, ct)))
        C.append(- k * E(j * k, old_u[i], (u0 - old_u[i]) / u0, u0, i0, ct))
        R.append(k * E(j * k, old_u[i], (u0 - old_u[i]) / u0, u0, i0, ct) * (2.0 * old_u[i+1] - 2.0 * old_u[i]) + 2.0 * h ** 2.0 * old_u[i] ** 2.0)

        v[0] = 0.0

        for i in range(1, ni):

            #  Uncomment if v is not neglected. Radial velocity.
            if j == 1:
                v[i] = (i * h) / ((i * h) + h) * (old_v[i-1] - h / k * (old_u[i] - u_initial[i]))
            elif j > 1:
                v[i] = (i * h) / ((i * h) + h) * (old_v[i-1] - h / k * (old_u[i] - old2_u[i]))

            A.append(k * (h * E(j * k, old_u[i], (u0 - old_u[i]) / u0, u0, i0, ct) - (i * h) * h * v[i] - 2.0 * (i * h) * E(j * k, old_u[i], (u0 - old_u[i]) / u0, u0, i0, ct)))
            B.append(4.0 * (i * h) * (h ** 2.0 * old_u[i] + k * E(j * k, old_u[i], (u0 - old_u[i]) / u0, u0, i0, ct)))
            C.append(k * ((i * h) * h * v[i] - 2.0 * (i * h) * E(j * k, old_u[i], (u0 - old_u[i]) / u0, u0, i0, ct) - h * E(j * k, old_u[i], (u0 - old_u[i]) / u0, u0, i0, ct)))
            if i < ni - 1:
                R.append(h * k * E(j * k, old_u[i], (u0 - old_u[i]) / u0, u0, i0, ct) * (old_u[i+1] - old_u[i-1]) + 2.0 * k * E(j * k, old_u[i], (u0 - old_u[i]) / u0, u0, i0, ct) * (i * h) * (old_u[i+1] - 2.0 * old_u[i] + old_u[i-1]) - (i * h) * h * k * old_v[i] * (old_u[i+1] - old_u[i-1]) + 4.0 * (i * h) * h ** 2.0 * old_u[i] ** 2.0)
            elif i == ni - 1:
                R.append(h * k * E(j * k, old_u[i], (u0 - old_u[i]) / u0, u0, i0, ct) * (u0 - old_u[i-1]) + 2.0 * k * E(j * k, old_u[i], (u0 - old_u[i]) / u0, u0, i0, ct) * (i * h) * (u0 - 2.0 * old_u[i] + old_u[i-1]) - (i * h) * h * k * old_v[i] * (u0 - old_u[i-1]) + 4.0 * (i * h) * h ** 2.0 * old_u[i] ** 2.0)

        # print time() - start

        C[0] += A[0]
        del A[0]
        R[-1] -= C[-1] * u0
        del C[-1]
        # start3 = time()
        old2_u = old_u
        old_u = thomas(A, B, C, R)

        old_v = v
        # print time() - start3
    # print time() - star,
    # print 's'

    ##### Code to calculate the average wake deficit in all the area of the rotor ###############

    ## Define function to integrate.

    ## p. 77 Adapting and calibration of existing wake models to meet the conditions inside offshore wind farms. For integrand squared momentum deficit.
    # def G(r, theta):
    #     z = sqrt(Y ** 2.0 + r ** 2.0 + 2.0 * Y * r * cos(theta))
    #     gauss = U0 * (1.0 - d1[n - 1] * exp(- 3.56 * (z / b(d1[n - 1])) ** 2.0))
    #     return r * (U0 - gauss) ** 2.0
    #
    # A = pi * 0.5 ** 2.0  ## Unitary diameter in this program.
    # U = U0 - sqrt((1.0 / A) * simpson_integrate2D(G, 0.0, 0.5, 5, 0.0, 2.0 * pi, 10))
    # print old_u[int(round(distance_perpendicular * 80.0, 0))]
    return 1.0 - old_u[int(distance_perpendicular * 50.0)] / u0
 def E(x1, Uf, Ud, Dm):  # Eddy viscosity term
     epsilon = F(x1) * (0.015 * b(Dm) * (Uf - Ud) + (karman ** 2.0) * I0 / 100.0)
     print epsilon
     return epsilon
def ainslie_full(ct, u0, distance_parallel, distance_perpendicular, i0):
    # centreline = open('centreline.dat', 'w')
    # velocity = open('velocity.dat', 'w')

    di = 2.0
    dj = distance_parallel
    # ni = int(di * 80)
    # nj = int(dj * 80)
    ni = nj = 100
    k = dj / float(nj)
    h = di / float(ni)

    nj += 1
    ni += 1
    Dmi = ct - 0.05 - (16.0 * ct - 0.5) * i0 / 10.0

    u = [0.0 for _ in range(ni)]
    v = [0.0 for _ in range(ni)]

    for g in range(ni):
        u[g] = u0 * (1.0 -
                     Dmi * exp(-3.56 * float(g * h)**2.0 / b(Dmi, ct)**2.0))

    old_u = u
    u_initial = u
    old_v = v
    old2_u = 0.0

    for j in range(1, nj):
        # start = time()
        A = []
        B = []
        C = []
        R = []

        i = 0
        A.append(-k * E(j * k, old_u[i], (u0 - old_u[i]) / u0, u0, i0, ct))
        B.append(2.0 *
                 (h**2.0 * old_u[i] + k * E(j * k, old_u[i],
                                            (u0 - old_u[i]) / u0, u0, i0, ct)))
        C.append(-k * E(j * k, old_u[i], (u0 - old_u[i]) / u0, u0, i0, ct))
        R.append(k * E(j * k, old_u[i], (u0 - old_u[i]) / u0, u0, i0, ct) *
                 (2.0 * old_u[i + 1] - 2.0 * old_u[i]) +
                 2.0 * h**2.0 * old_u[i]**2.0)

        v[0] = 0.0

        for i in range(1, ni):

            #  Uncomment if v is not neglected. Radial velocity.
            if j == 1:
                v[i] = (i * h) / ((i * h) + h) * (old_v[i - 1] - h / k *
                                                  (old_u[i] - u_initial[i]))
            elif j > 1:
                v[i] = (i * h) / ((i * h) + h) * (old_v[i - 1] - h / k *
                                                  (old_u[i] - old2_u[i]))

            A.append(k * (h * E(j * k, old_u[i],
                                (u0 - old_u[i]) / u0, u0, i0, ct) -
                          (i * h) * h * v[i] - 2.0 *
                          (i * h) * E(j * k, old_u[i],
                                      (u0 - old_u[i]) / u0, u0, i0, ct)))
            B.append(
                4.0 * (i * h) *
                (h**2.0 * old_u[i] + k * E(j * k, old_u[i],
                                           (u0 - old_u[i]) / u0, u0, i0, ct)))
            C.append(k * ((i * h) * h * v[i] - 2.0 *
                          (i * h) * E(j * k, old_u[i],
                                      (u0 - old_u[i]) / u0, u0, i0, ct) -
                          h * E(j * k, old_u[i],
                                (u0 - old_u[i]) / u0, u0, i0, ct)))
            if i < ni - 1:
                R.append(h * k *
                         E(j * k, old_u[i], (u0 - old_u[i]) / u0, u0, i0, ct) *
                         (old_u[i + 1] - old_u[i - 1]) + 2.0 * k *
                         E(j * k, old_u[i], (u0 - old_u[i]) / u0, u0, i0, ct) *
                         (i * h) *
                         (old_u[i + 1] - 2.0 * old_u[i] + old_u[i - 1]) -
                         (i * h) * h * k * old_v[i] *
                         (old_u[i + 1] - old_u[i - 1]) + 4.0 *
                         (i * h) * h**2.0 * old_u[i]**2.0)
            elif i == ni - 1:
                R.append(h * k *
                         E(j * k, old_u[i], (u0 - old_u[i]) / u0, u0, i0, ct) *
                         (u0 - old_u[i - 1]) + 2.0 * k *
                         E(j * k, old_u[i], (u0 - old_u[i]) / u0, u0, i0, ct) *
                         (i * h) * (u0 - 2.0 * old_u[i] + old_u[i - 1]) -
                         (i * h) * h * k * old_v[i] * (u0 - old_u[i - 1]) +
                         4.0 * (i * h) * h**2.0 * old_u[i]**2.0)

        # print time() - start

        C[0] += A[0]
        del A[0]
        R[-1] -= C[-1] * u0
        del C[-1]
        # start3 = time()
        old2_u = old_u
        old_u = thomas(A, B, C, R)

        old_v = v
        # print time() - start3
    # print time() - star,
    # print 's'

    # Code to calculate the average wake deficit in all the area of the rotor ###############

    # Define function to integrate.

    # p. 77 Adapting and calibration of existing wake models to meet the conditions inside
    # -----offshore wind farms. For integrand squared momentum deficit.

    # def G(r, theta):
    #     z = sqrt(Y ** 2.0 + r ** 2.0 + 2.0 * Y * r * cos(theta))
    #     gauss = U0 * (1.0 - d1[n - 1] * exp(- 3.56 * (z / b(d1[n - 1])) ** 2.0))
    #     return r * (U0 - gauss) ** 2.0
    #
    # A = pi * 0.5 ** 2.0  ## Unitary diameter in this program.
    # U = U0 - sqrt((1.0 / A) * simpson_integrate2D(G, 0.0, 0.5, 5, 0.0, 2.0 * pi, 10))
    # print old_u[int(round(distance_perpendicular * 80.0, 0))]
    return 1.0 - old_u[int(distance_perpendicular * 50.0)] / u0
def ainslie_full(parallel, perpendicular, discretisation_parallel, discretisation_perpendicular, ct=0.79, u0=8.5, i0=8.0):
    Dmi = ct - 0.05 - (16.0 * ct - 0.5) * i0 / 1000.0

    if perpendicular == 0.0:
        perpendicular = 0.01
    h = perpendicular / discretisation_perpendicular
    k = parallel / discretisation_parallel

    nj = discretisation_parallel
    ni = discretisation_perpendicular

    u = [[0.0 for _ in range(ni)]]
    v = [[0.0 for _ in range(ni)] for _ in range(nj)]

    for g in range(ni):
        u[0][g] = u0 * (1.0 - Dmi * exp(- 3.56 * float(g * h) ** 2.0 / b(Dmi, ct) ** 2.0))

    print('\rPercentage: 0.0 %. Time remaining:  s'),

    for j in range(1, nj):

        start = time()

        A = []
        B = []
        C = []
        R = []

        for i in range(ni):
            #  Uncomment if v is not neglected. Radial velocity.
            if i == 1:
                v[j][i] = (i * h) / ((i * h) + h) * (v[j-1][i-1] - h / k * (u[j-1][i] - u[0][i]))
            elif i > 1:
                v[j][i] = (i * h) / ((i * h) + h) * (v[j-1][i-1] - h / k * (u[j-1][i] - u[j-2][i]))

            if i == 0:
                A.append(- k * E(j * k, u[j-1][i], (u0 - u[j-1][i]) / u0, u0, i0, ct))
                B.append(2.0 * (h ** 2.0 * u[j-1][i] + k * E(j * k, u[j-1][i], (u0 - u[j-1][i]) / u0, u0, i0, ct)))
                C.append(- k * E(j * k, u[j-1][i], (u0 - u[j-1][i]) / u0, u0, i0, ct))
                R.append(k * E(j * k, u[j-1][i], (u0 - u[j-1][i]) / u0, u0, i0, ct) * (2.0 * u[j-1][i+1] - 2.0 * u[j-1][i]) + 2.0 * h ** 2.0 * u[j-1][i] ** 2.0)

            else:
                A.append(k * (h * E(j * k, u[j-1][i], (u0 - u[j-1][i]) / u0, u0, i0, ct) - (i * h) * h * v[j][i] - 2.0 * (i * h) * E(j * k, u[j-1][i], (u0 - u[j-1][i]) / u0, u0, i0, ct)))
                B.append(4.0 * (i * h) * (h ** 2.0 * u[j-1][i] + k * E(j * k, u[j-1][i], (u0 - u[j-1][i]) / u0, u0, i0, ct)))
                C.append(k * ((i * h) * h * v[j][i] - 2.0 * (i * h) * E(j * k, u[j-1][i], (u0 - u[j-1][i]) / u0, u0, i0, ct) - h * E(j * k, u[j-1][i], (u0 - u[j-1][i]) / u0, u0, i0, ct)))
                if i < ni - 1:
                    R.append(h * k * E(j * k, u[j-1][i], (u0 - u[j-1][i]) / u0, u0, i0, ct) * (u[j-1][i+1] - u[j-1][i-1]) + 2.0 * k * E(j * k, u[j-1][i], (u0 - u[j-1][i]) / u0, u0, i0, ct) * (i * h) * (u[j-1][i+1] - 2.0 * u[j-1][i] + u[j-1][i-1]) - (i * h) * h * k * v[j-1][i] * (u[j-1][i+1] - u[j-1][i-1]) + 4.0 * (i * h) * h ** 2.0 * u[j-1][i] ** 2.0)
                elif i == ni - 1:
                    R.append(h * k * E(j * k, u[j-1][i], (u0 - u[j-1][i]) / u0, u0, i0, ct) * (u[j-1][i] - u[j-1][i-1]) + 2.0 * k * E(j * k, u[j-1][i], (u0 - u[j-1][i]) / u0, u0, i0, ct) * (i * h) * (u[j-1][i] - 2.0 * u[j-1][i] + u[j-1][i-1]) - (i * h) * h * k * v[j-1][i] * (u[j-1][i] - u[j-1][i-1]) + 4.0 * (i * h) * h ** 2.0 * u[j-1][i] ** 2.0)

        C[0] += A[0]
        del A[0]
        R[-1] -= C[-1] * u0
        del C[-1]

        u.append(thomas(A, B, C, R))

        periter = time()
        lleva = float(j) / float(nj)
        falta = (periter - start) * (nj - j - 1)
        # print('\rPercentage: {0:2.2f} %. Time remaining: {1:2.1f} s'.format(100.0 * lleva, falta)),

    print 'Position = ' + str(nj * k) + ', ' + str(ni * h)
    return u[-1][-1]