The simple equations below assume a plane infinite wall or interface.
This is of course never the case. Nevertheless, these three equations
could really help because:
- they give an approximation of the total reflection angle.
- they predict the amount of ultrasonic energy that will penetrate in the liquid.
- they predict the amount of energy that tends to remain in the wall.
Zi is the acoustic impedance of the medium i, which is equal to the
product of the sound speed by the density of the medium i;
R is the ratio of the reflected intensity to the incident intensity;
D is the ratio of the refracted intensity to the incident intensity.