A Method for Direct Localized Sound Speed Estimates Using Registered Virtual Detectors

A method for direct localized sound speed estimates using registered virtual detectors.

Accurate sound speed estimates are desirable in a number of fields. In an effort to increase the spatial resolution of sound speed estimates, a new method is proposed for direct measurement of sound speed between arbitrary spatial locations. The method uses the sound speed estimator developed by Anderson and Trahey. Their least squares fit of the received waveform's curvature provides an estima...

A direct method for photoacoustic tomography with inhomogeneous sound speed

A new generalized model for predict speed of sound of refrigerants

In consideration of physical and chemical properties of pure substances, speed of sound is one of important quantity which can used to calculate many of other thermo-physical properties such as isothermal compressibility, Joule-Thomson coefficient, isobaric heat capacity and etc. These thermo-physical properties are the main parameters in industrial and chemical processes. Development of accura...

Direct measurement of the speed of sound by using a microphone and a speaker

We present a simple and accurate experiment to obtain the speed of sound in air by using a conventional speaker and a microphone connected to a computer. A free open source digital audio editor and recording computer software application allows determining the time-of-flight of the wave for different distances from which the speed of sound is calculated. The result is in very good agreement wit...

A posteriori error estimates for the virtual element method

An posteriori error analysis for the virtual element method (VEM) applied to general elliptic problems is presented. The resulting error estimator is of residual-type and applies on very general polygonal/polyhedral meshes. The estimator is fully computable as it relies only on quantities available from the VEM solution, namely its degrees of freedom and element-wise polynomial projection. Uppe...