M. Suresh,

The general concept is that the greater the frequency is, the faster the rate of attenuation becomes.

Here's some literature discussing this topic in further detail:

https://ieeexplore.ieee.org/document/7992007

https://www.sciencedirect.com/science/article/abs/pii/0301562979900188

Article Frequency Dependence of Ultrasonic Attenuation and Velocity ...

Article Effect of Frequency-Dependent Attenuation on Predicted Histo...

Article Frequency dependence of surface acoustic wave swimming

Dear Dr. M. Suresh The question seems to be difficult and to be simple at the same time. The reason is that in solids there are three propagating modes: P-longitudinal, SV-transversal and SH-transversal, so there are three attenuation coefficients alpha_ij depending on the direction-i and on the specific mode-j. For liquids or a gas althought, there are only P waves propagating. So there will be only one attenuation coeficient alpha_P. Hope this helps. Regards. Add: I don't know what happens at the inteface. But the alpha_P value should change.

Thank you Firas and Contreras.

Basically I want to explore use of ultrasound propagation in different two-phase gas-liquid flow regimes including their amplitude attenuation in the gas-liquid mixtures.

Any technical studies with reference to bubbly flow (gas-liquid) in vertical and horizontal pipes will help.

M. Suresh,

You're most welcome! Glad I could help.