Fig 1.
Basic principle of ultrasonic temperature measurement.
Fig 2.
(a) Schematic of the experimental system. (b) Photograph of the actual system. (A) is the trough with distilled water, (B) is one of the transducers, (C) is the mercuric thermometer, (D) is the thermostatic water bath, (E) is the signal transceiver module, (F) is the PC, (G) is the power supply and (H) is the frequency meter. (c) Photograph of the signal transceiver module. (A) is the FPGA, (B) is the DDR memory, (C) is the Ethernet port, (D) are the transmitting channels and (E) are the receiving channels. (d) The Photograph of one of the adopted mercuric thermometers, which ranges from 35°C ∼ 39°C.
Fig 3.
The function that ultrasound velocity versus temperature in distilled water.
Table 1.
The calibrated results.
Table 2.
Uncertainty analysis of the calibrated results.
Fig 4.
Results of measured ultrasonic temperature.
Fig 5.
Temperature errors of ultrasonic measurement.
(a) The path length is measured by a slide caliper ruler. (b) Using the calibrated results.