Galovic, S.; Djordjevic, A.I.; Kovacevic, B.Z.; Djordjevic, K.L.; Chevizovich, D. Influence of Local Thermodynamic Non-Equilibrium to Photothermally Induced Acoustic Response of Complex Systems. Fractal Fract.2024, 8, 399.
Galovic, S.; Djordjevic, A.I.; Kovacevic, B.Z.; Djordjevic, K.L.; Chevizovich, D. Influence of Local Thermodynamic Non-Equilibrium to Photothermally Induced Acoustic Response of Complex Systems. Fractal Fract. 2024, 8, 399.
Galovic, S.; Djordjevic, A.I.; Kovacevic, B.Z.; Djordjevic, K.L.; Chevizovich, D. Influence of Local Thermodynamic Non-Equilibrium to Photothermally Induced Acoustic Response of Complex Systems. Fractal Fract.2024, 8, 399.
Galovic, S.; Djordjevic, A.I.; Kovacevic, B.Z.; Djordjevic, K.L.; Chevizovich, D. Influence of Local Thermodynamic Non-Equilibrium to Photothermally Induced Acoustic Response of Complex Systems. Fractal Fract. 2024, 8, 399.
Abstract
In this paper, the time-resolved model of photoacoustic signal for samples with a complex inner structure is derived including local non-equilibrium of structural elements with multiple degrees of freedom, i.e. structural entropy of the system. The local non-equilibrium is taken into account through the fractional operator. By analyzing the model for two types of time-dependent excitation, a very short pulse and a very long pulse, it is shown that the rates of non-equilibrium relaxations in complex samples can be measured by applying the derived model and time-domain measurements. Limitations of the model and further directions of its development are discussed.
Keywords
heat transfer; irreversibility; local non-equilibrium; time delayed equation; fractional calculus; subdiffusion; Mittag-Leffler function; time-domain photoacoustic
Subject
Physical Sciences, Condensed Matter Physics
Copyright:
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