arim.scat.sdh_2d_scat#
- arim.scat.sdh_2d_scat(inc_theta, out_theta, frequency, radius, longitudinal_vel, transverse_vel, min_terms=10, term_factor=4, to_compute=frozenset({'LL', 'LT', 'TL', 'TT'}))[source]#
Scattering coefficients for a side-drilled hole in 2D
The scattered field is given by:
u_scat(r, theta) = u0 * sqrt(1 / r) * exp(-i k r + i omega i ray) * (sqrt(lambda_L) A(theta) e_r + sqrt(lambda_T) B(theta) e_theta)
where A(theta) and B(theta) are the scattering coefficients for respectively L and T scattered waves and where e_r and e_theta are the two vectors of the cylindrical coordinate system.
The coefficient for LL, LT, TL and TT are obtained from Lopez-Sanchez’s paper, equations 33, 34, 39, 40. See also Brind’s paper.
Another difference with these papers is the definition of theta. We use the NDT convention where pulse-echo corresponds to theta=0. For Brind, Lopez-Sanchez et al. pulse-echo corresponds to theta=pi.
The number of factor in the sum is:
maxn = max(min_terms, ceil(term_factor * alpha), ceil(term_factor * beta))
- Parameters:
inc_theta (ndarray) – Angle in radians. Pulse echo case corresponds to inc_theta = out_theta
out_theta (ndarray) – Angle in radians.
frequency (float)
radius (float)
longitudinal_vel (float)
transverse_vel (float)
min_terms (int)
term_factor (int)
to_compute (set) – See
SCAT_KEYS
- Returns:
result – Keys corresponds to ‘to_compute’ argument. Values have the shape of theta.
- Return type:
dict
References