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  2. Attenuation coefficient - Wikipedia

    en.wikipedia.org/wiki/Attenuation_coefficient

    The attenuation coefficient of a volume, denoted μ, is defined as [6] =, where Φ e is the radiant flux;; z is the path length of the beam.; Note that for an attenuation coefficient which does not vary with z, this equation is solved along a line from =0 to as:

  3. Attenuation - Wikipedia

    en.wikipedia.org/wiki/Attenuation

    Attenuation coefficients are used to quantify different media according to how strongly the transmitted ultrasound amplitude decreases as a function of frequency. The attenuation coefficient ( α {\displaystyle \alpha } ) can be used to determine total attenuation in dB in the medium using the following formula:

  4. Ultrasound attenuation spectroscopy - Wikipedia

    en.wikipedia.org/wiki/Ultrasound_attenuation...

    Ultrasound attenuation spectroscopy is a method for characterizing properties of fluids and dispersed particles. It is also known as acoustic spectroscopy. There is an international standard for this method. [1] [2] Measurement of attenuation coefficient versus ultrasound frequency yields

  5. Stokes's law of sound attenuation - Wikipedia

    en.wikipedia.org/wiki/Stokes's_law_of_sound...

    In acoustics, Stokes's law of sound attenuation is a formula for the attenuation of sound in a Newtonian fluid, such as water or air, due to the fluid's viscosity.It states that the amplitude of a plane wave decreases exponentially with distance traveled, at a rate α given by = where η is the dynamic viscosity coefficient of the fluid, ω is the sound's angular frequency, ρ is the fluid ...

  6. Acoustic attenuation - Wikipedia

    en.wikipedia.org/wiki/Acoustic_attenuation

    This effect can be quantified through the Stokes's law of sound attenuation. Sound attenuation may also be a result of heat conductivity in the media as has been shown by G. Kirchhoff in 1868. [1] [2] The Stokes-Kirchhoff attenuation formula takes into account both viscosity and thermal conductivity effects.

  7. Mechanical index - Wikipedia

    en.wikipedia.org/wiki/Mechanical_index

    f c is the center frequency of the ultrasound pulse . MI is measured with a calibrated hydrophone in a tank of degassed water. The pulse pressure amplitudes are measured along the central axis of the ultrasound beam. The P r is calculated by reducing it using an attenuation coefficient of 0.3 dB/cm/MHz. [2]

  8. Mathematical descriptions of opacity - Wikipedia

    en.wikipedia.org/wiki/Mathematical_descriptions...

    absorption coefficient is essentially (but not quite always) synonymous with attenuation coefficient; see attenuation coefficient for details; molar absorption coefficient or molar extinction coefficient , also called molar absorptivity , is the attenuation coefficient divided by molarity (and usually multiplied by ln(10), i.e., decadic); see ...

  9. Ultrasonic flow meter - Wikipedia

    en.wikipedia.org/wiki/Ultrasonic_flow_meter

    Schematic view of a flow sensor. An ultrasonic flow meter is a type of flow meter that measures the velocity of a fluid with ultrasound to calculate volume flow. Using ultrasonic transducers, the flow meter can measure the average velocity along the path of an emitted beam of ultrasound, by averaging the difference in measured transit time between the pulses of ultrasound propagating into and ...