Certain microstructural features of materials, such as grain size in metals, porosity in ceramics, and structural phase compositions, are important for determining mechanical properties. Many of these microstructural features have been characterized by ultrasonic wave propagation measurements, such as wave velocity and attenuation. Real-time monitoring of ultrasonic wave propagation during the ...

In the four previous parts of this series of articles, level measurement using a floating system, using pressure instruments, using radar waves and using ultrasonic waves were discussed. The instruments offered by Indumart company applicable for each method were also recommended. In the final part of this article, level measurement using capacitance, conductivity probes, vibration forks, therma...

This paper proposes an efficient array beam-forming method using spatial matched filtering (SMF) for ultrasonic imaging. In the proposed method, ultrasonic waves are transmitted from an array subaperture with fixed transmit focus as in conventional array imaging. At receive, radio frequency echo signals from each receive channel are passed through a spatial matched filter that is constructed ba...

The absorption of compressional and shear waves in many viscoelastic solids has been experimentally shown to follow a frequency power law. It is now well established that this type of loss behavior can be modeled using fractional derivatives. However, previous fractional constitutive equations for viscoelastic media are based on temporal fractional derivatives. These operators are non-local in ...

The proposed method for measuring the liquid level focuses on the ultrasonic impedance and echo energy inside a metal wall, to which the sensor is attached directly, not on ultrasonic waves that penetrate the gas-liquid medium of a container. Firstly, by analyzing the sound field distribution characteristics of the sensor in a metal wall, this paper proposes the concept of an "energy circle" an...

Optoacoustic imaging relies on the ultrasonic detection of pressure waves created after optical absorption. In this work we demonstrate imaging single red blood cells using an ultrasonic detection system at 200 and 400 MHz. ©2010 Optical Society of America OCIS codes: (170.3880) Medical and biological imaging; (350.0350) Other areas of optics

Ultrasonic measurement techniques can be used to determine some characteristics of turbulent flows. In this work measurements of the difference in propagation times of ultrasonic waves along two paths are combined with the Kolmogorov (j )-power law to study characteristics of grid-generated turbulence. The paper focuses on ultrasonic measurements of turbulent flow using the travel-time techniqu...

The practical problem. In many practical situations, it is extremely important to be able to detect hidden cracks (and other possible faults) in aerospace and other structures. One way of testing the structural integrity of such structures is by using ultrasonic waves. For thin plates, Lamb waves (which direct the energy along the plate) are especially useful. To use these waves, we set up a tr...

We have developed a novel instrument for measuring the surface tension of liquids. It utilizes ultrasonic and optical methods to excite and detect a capillary wave packet. A focused ultrasonic transducer is used to generate a mound on the surface of a liquid. Capillary waves propagate radially outward from the mound, and a noncontacting confocal optical microscope measures the amplitude of the ...

This paper aims the studying, modeling and testing of models of linear motors which use ultrasonic waves to achieve the movement. The studied motors are characterized by the positioning accuracy, small inertia, wide speed control (does not require gears and gearboxes), easy control, high torque per unit weight, miniaturization, simple structure, low noise, decreasing time-speed characteristic. ...