Laboratory investigation of the effect of salt fingers on sound signal propagation in water

The speed of sound is a function of temperature, salinity and water pressure, and processes caused by vertical gradients of temperature and salinity, such as saltfingering structures, can affect sound speed and propagation.In this research, the effect of Salt Fingers on the sound signal has been investigated in a laboratory environment and in a homogeneous water tank.In the presence of salt-fingering, the amplitude of direct and reflected signals from the surface is reduced, and the signals are received by the receiver with a time delay and with a slight decrease (5-10 dB) in sound power.By increasing the depth of the sound source, the scattering and deflection of the rays and the change in the amplitude of the sound signal are reduced.In the absence of salt fingers, the sound signal is propagated with the least energy loss and the sound rays are deflected towards the surface.But in the presence of SF and with the increase of salinity on the surface, the scattering and loss of the sound signal increases (up to 85 dB) and the sound rays are deflected towards the bottom of the tank.This effect is greater on the rays that propagate with a smaller angle.