An open steel vessel contains liquid metal to a depth of about 0.75 m. It is proposed to measure the depth of liquid using ultrasonic pulse reflection techniques. A quartz crystal attached to the base of the vessel is to act alternatively as a transmitter and receiver. Using the data given below and in

(a) Calculate the ‘round trip’ time TT and the fraction of received power to transmitted power.

(b) Choose suitable values for pulse width and repetition times.


Velocity of sound in liquid metal = 1.5 × 103 m s−1

Density of liquid metal = 5 × 103 kg m−3

Power attenuation coefficient = 0.1 m−1

Natural frequency of quartz crystal = 1 MHz