Bragg scattering by an irregular versatile seabed in the presence of current

The Bragg scattering due to an undulated elastic bottom in the presence of a uniform current is discussed in the present paper. The conditions of Bragg resonance are derived analytically and discussed numerically for various values of physical parameters. The mathematical techniques used for discussing the analysis are the perturbation and Fourier transform methods. It is seen that the amplitude of the Bragg reflection increases with the increase in the flexibility factor in the versatile floor of the sea, and there is a significant impact of the current speed on Bragg reflection and transmission coefficients. The maximum value of the amplitude of Bragg reflection is observed to decrease as the Froude number increases. Again, it is seen that the transmitted energy produced in the presence of uniform current does not fluctuate considerably when the nature of an elastic bottom gets closer to that of a stiff floor. The blocking resonance in the presence of current and elastic bottom is analyzed by neglecting the small bottom undulation. A significant effect of blocking resonance on Bragg reflection and transmission is observed.