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Momentum and angular momentum reciprocity theorems for acoustic fields.
1School of Physics and Technology, Nanjing Normal University, Nanjing 210023, China.
The Journal of the Acoustical Society of America
|July 2, 2024
Summary
Reciprocity theorems for acoustic fields, based on momentum and angular momentum, reveal correlations between acoustic systems. This work deepens understanding of reciprocity as a universal law for linear physical fields.
Area of Science:
- Physics
- Acoustics
- Electromagnetics
Background:
- Reciprocity theorems are universal in linear physical systems, describing input-output relationships.
- Electromagnetic fields have well-established reciprocity theorems for energy, momentum, and angular momentum.
- Acoustic fields lack comprehensive reciprocity theorems, particularly concerning momentum and angular momentum.
Purpose of the Study:
- To derive momentum-based and angular momentum-based reciprocity theorems for acoustic fields.
- To systematically summarize and analogically study reciprocity theorems across acoustic and electromagnetic fields.
- To deepen the understanding of reciprocity theorems as a universal law for linear physical fields.
Main Methods:
- Derivation of acoustic reciprocity theorems from linear acoustic theory.
- Comparative analysis and analogical study of acoustic and electromagnetic reciprocity theorems.
Main Results:
- Successfully derived momentum-based and angular momentum-based reciprocity theorems for acoustic fields.
- Demonstrated correlations between two acoustic systems from momentum and angular momentum perspectives.
- Provided a systematic summary and analogical study of various reciprocity theorems.
Conclusions:
- Acoustic reciprocity theorems, analogous to electromagnetic ones, enhance the theory of linear acoustic systems.
- The findings offer theoretical guidance for practical applications in audio signal processing and acoustic measurement.
- Reciprocity theorems are confirmed as a universal principle applicable to diverse linear physical fields.
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