An ultrasonic transit time flowmeter was tested over Reynolds numbers from 1000 to 100 000 in a calibration facility that generates gas flows with controlled temperature and composition. The gas mixtures were composed of air, nitrogen, carbon dioxide, water vapor, and argon, and the mixture temperature ranged from 290 K to 450 K. The test program was conducted to determine the sensitivity of th...

The measurement kit of the ADA-CAT (Americans With Disabilities Act-Compliance Assessment Toolkit) consists of measurement instruments, such as a measuring tape, a sound level meter, a light level meter, and a magic slope block. Perhaps the most important tool is the measuring tape for length and height measurement as distances are used so prolifically in the ADA assessment process. Currently, ...

Pulse ultrasound technique has been applied to measure the reflected echo signals from vapor bubbles in boiling two-phase flow. In this study, an ultrasonic transducer was developed for the ultrasonic measurement in boiling two-phase flow under the atmospheric pressure. Since the Curie point of piezoelements of the transducer is above 250 ̊C, it has an allowable temperature limit of 120 ̊C. The b...

Ultrasound technology was used to analyse the freezing behaviour of orange juice. The ultrasonic properties of orange juice, specifically velocity and attenuation coefficient, were characterised as the temperature was decreased from 20 to −50 ◦C. The results were compared with NMR free induction decay data and correlated with the amount of unfrozen water present in the frozen sample. The veloci...

One of the main goals in ultrasonic Doppler blood flow measurement is the estimation of the mean velocity. The Doppler signal’s instantaneous frequency has traditionally been used to estimate the mean velocity. In this work, a non-uniform discrete time frequency distribution is proposed: the warped discrete Choi Williams distribution (WTFDCW). The proposed procedure estimates the instantaneous ...

A non-contact vibration measuring technique based on ultrasonic Doppler effect is studied. Two effects induce phase modulation on the received ultrasound signal, which are Doppler effect and nonlinear parametric effect. With the increasing of vibrating frequency, the phase variation due to parametric effect is getting greater and greater. In this paper, by measuring the acoustic pressure genera...