Ultrasonic Measurements of Temperature in Aqueous Solutions: Why and How

Table 1

Features of various ultrasonic evaluation methods.

Method	Key to Figure 1	Transducer	Positives	Comments
Through transmission	(a)	T + R	Simpler electronics compared to (c)	Continuous wave and pulse operation are possible
Pitch-catch	(b)	T + R	Single side access required only compared to (a)	Same as (a)
Pulse-echo	(c)	T/R	Single transducer required only compared to (a, b)	Pulse operation only
Backscatter	(d)	T/R	No reflector required compared to (c)	Same as (c); effective for highly scattered media
Acoustic emission	(e)	R	No need for transmitter and its driver	Signals are difficult to interpret; limited applicability