Visualization of the hot chocolate sound effect by spectrograms

0379958 - ÚT 2013 RIV GB eng J - Článek v odborném periodiku
Trávníček, Zdeněk - Fedorchenko, Alexander I. - Pavelka, Miroslav - Hrubý, Jan
Visualization of the hot chocolate sound effect by spectrograms.
Journal of Sound and Vibration. Roč. 331, č. 25 (2012), s. 5387-5392. ISSN 0022-460X. E-ISSN 1095-8568
Grant CEP: GA AV ČR(CZ) IAA200760801; GA ČR(CZ) GCP101/11/J019
Výzkumný záměr: CEZ:AV0Z20760514
Klíčová slova: hot chocolate effect * gas-liquid mixture * speed of sound
Kód oboru RIV: BK - Mechanika tekutin
Impakt faktor: 1.613, rok: 2012
http://www.sciencedirect.com/science/article/pii/S0022460X12005640

We present an experimental and theoretical analysis of the hot chocolate effect. The sound effect is evaluated using time-frequency signal processing, resulting in a quantitative visualization by spectrograms. This method allows us to capture the whole phenomenon, namely, to quantify the dynamics of the rising pitch. A general form of the time dependence volume fraction of the bubbles is proposed. We show that the effect occurs due to the nonlinear dependence of the speed of sound in the gas/liquid mixture on the volume fraction of the bubbles and the nonlinear time dependence of the volume fraction of the bubbles.
Trvalý link: http://hdl.handle.net/11104/0210800