Acoustical Physics最新文献

{"title":"The Possibility of Detecting Geological Bodies without Velocity Contrast in the Field of Surface Waves","authors":"A. A. Tsukanov,&nbsp;A. V. Gorbatikov","doi":"10.1134/S1063771024603054","DOIUrl":"10.1134/S1063771024603054","url":null,"abstract":"<p>Using a mathematical model within the framework of the linear theory of elasticity, the problem—interesting from both theoretical and practical points of view—of surface wave irradiation of an elastic half-space containing a single buried body whose physical properties are different from those of the host medium material, but whose elastic moduli and density change in a consistent manner so that the velocity of both P- and S-waves do not differ from those in the host medium, is considered. It is shown that such buried heterogeneities, despite the lack of velocity contrast, can be detected and mapped both in plan view and at depth in the broadband field of Rayleigh surface waves based on variations in the spectral amplitude of the signal recorded at several points on the surface.</p>","PeriodicalId":455,"journal":{"name":"Acoustical Physics","volume":"71 2","pages":"253 - 262"},"PeriodicalIF":1.2,"publicationDate":"2025-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1134/S1063771024603054.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144861542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Statistical Characteristics of the Internal Structure of the Seismic Background over a Hydrocarbon Deposit","authors":"I. Ya. Chebotareva","doi":"10.1134/S1063771024602565","DOIUrl":"10.1134/S1063771024602565","url":null,"abstract":"<div><p>The fine structure of the seismic background in the territory of an oil field was studied using polyspectral analysis and surrogate models. The statistical test for Gaussianity and linearity showed that the natural seismic background in the 1–50 Hz frequency range is a nonlinear process. Bicoherence graphs revealed statistically significant peaks of phase-coupled triplets with a characteristic geometry of peak clustering in the triangular principal domain. To analyze the quasi-noise component of the seismic background, surrogate time series with a randomized phase spectrum were generated, the bispectra of which are free of triplet peaks. Bispectral analysis of surrogate series showed the presence of a non-Gaussian quasi-noise component in the seismic background in the frequency range of 1–6 Hz. Previously, the results of the analysis of the used set of records by two completely different methods, each of which extracts information from different components of the seismic background, quasi-noise and regular, were published. These studies showed that each of the two components contains information sufficient to estimate the total thickness of the productive intervals under the recording point. Based on the results of the bispectral analysis and the features of the algorithms of the two methods, a conclusion was made that the quadratically phase-coupled triplets and the non-Gaussian quasi-noise component in the field territory are manifestations of endogenic seismic emission and are generated by the same nonlinear process developing in the vicinity of an oil-saturated reservoir. The mechanism of seismic emission should be sought in the class of phenomena with quadratic nonlinearity. The statistical characteristics of the internal structure of the seismic background near oil wells have similar features that differ greatly from the statistical characteristics of the seismic record near a “dry” well located outside the reservoir and not producing oil. Previously unknown prognostic features of the oil/water saturation type of rocks have been identified.</p></div>","PeriodicalId":455,"journal":{"name":"Acoustical Physics","volume":"71 2","pages":"263 - 276"},"PeriodicalIF":1.2,"publicationDate":"2025-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144861572","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Correlation Function of Equilibrium Thermal Pressure Fluctuations in Viscous Heat-Conducting Gas","authors":"M. A. Demyanov,&nbsp;V. F. Kopiev,&nbsp;M. A. Yudin","doi":"10.1134/S1063771024603108","DOIUrl":"10.1134/S1063771024603108","url":null,"abstract":"<div><p>The problem of finding the spatiotemporal correlation function of pressure thermal fluctuations of gas near thermodynamic equilibrium is considered. The correlation function of pressure field equilibrium thermal fluctuations is obtained for viscous heat-conducting perfect gas filling an unbounded Euclidean space. The influence of the boundary on the correlation characteristics of thermal fluctuations of pressure is investigated using the example of a viscous isentropic perfect gas filling a small-section pipe with boundary conditions of a solid wall at the ends and periodic conditions for the case of a pipe closed in a circle.</p></div>","PeriodicalId":455,"journal":{"name":"Acoustical Physics","volume":"71 2","pages":"240 - 252"},"PeriodicalIF":1.2,"publicationDate":"2025-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144861539","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Geometry-Dependent Performance in Sound Localization: A Study of 18-Element Microphone Arrays","authors":"L. Huang,&nbsp;R. Zeng","doi":"10.1134/S1063771024602450","DOIUrl":"10.1134/S1063771024602450","url":null,"abstract":"<p>This study examines the performance of six different two-dimensional, 18-element microphone array geometries—BK, Ring, Reuleaux, Logarithmic, Triangle, and Starfish—for sound source localization. The arrays’ performances are systematically evaluated using beamforming algorithms and acoustic pressure reconstruction, focusing on key metrics such as main lobe width, side lobe magnitude, reconstruction error, and resolution quality over frequencies ranging from 0 to 3000 Hz. Additionally, the study investigates the adaptability of these configurations at various distances and explores their frequency-dependent behavior. The results indicate that array geometry substantially impacts localization accuracy, with the Starfish configuration demonstrating superior overall performance, exhibiting the narrowest main lobe width, highest main lobe amplitude, lowest reconstruction error, and consistently high resolution. Thus, the Starfish configuration is recommended as optimal for effective sound source localization applications<i>.</i></p>","PeriodicalId":455,"journal":{"name":"Acoustical Physics","volume":"71 2","pages":"135 - 143"},"PeriodicalIF":1.2,"publicationDate":"2025-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144861571","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental Method for Determining Energy Losses in Oscillatory Systems Based on ARMA Modeling","authors":"I. A. Karpov,&nbsp;Yu. I. Bobrovnitskii","doi":"10.1134/S1063771025600329","DOIUrl":"10.1134/S1063771025600329","url":null,"abstract":"<p><b>Abstract</b>—Damping (dissipation, energy losses) is the most important parameter of all mechanical oscillatory systems, in addition to elasticity and inertia. Its special role is due to the fact that it directly determines the maximum amplitudes of free and forced vibrations of systems and, accordingly, their dynamic strength and reliability, noise and ecology. Due to the poor study of the physical processes of damping, it is measured experimentally. This article presents one of the new efficient methods for experimental determination of losses, characterized by simplicity, high accuracy and a wide range of applicability. The main attention is paid to substantiation of the method, its properties, and its verification in numerical and laboratory experiments. The method is recommended for measuring the losses of composite highly damped oscillatory systems, where known methods do not work or are too complex.</p>","PeriodicalId":455,"journal":{"name":"Acoustical Physics","volume":"71 2","pages":"144 - 162"},"PeriodicalIF":1.2,"publicationDate":"2025-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144861569","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sound Insulation of Fuselage Aircraft Structures with Different Compositions of Resonance Elements","authors":"A. Ya. Zverev,&nbsp;L. A. Lazarev,&nbsp;I. V. Pankratov","doi":"10.1134/S1063771024603091","DOIUrl":"10.1134/S1063771024603091","url":null,"abstract":"<p>Reducing noise in the cabin of propeller aircraft is an urgent problem of internal acoustics, since traditional sound-insulating structures are insufficiently effective in the low-frequency region. One promising method for solving it is to use resonance systems, with which it is possible to significantly increase the sound insulation of the fuselage structure of aircraft in this frequency range. The study determined the effect of resonance systems on the sound-insulating ability of flat and cylindrical panels without and with cross stiffening simulating the body bulkhead frame was experimentally determined, as well as the effectiveness of facing the passenger compartment with resonance systems with different compositions. Tests were carried out in sound chambers and on a full-scale bench, which is a real passenger plane. The tested structures were faced with elastoacoustic compensators of various types with resonance elements made of foil, micalent paper, and thermopolyurethane. It is shown that the efficiency of resonance systems can reach 10–20 dB or more.</p>","PeriodicalId":455,"journal":{"name":"Acoustical Physics","volume":"71 2","pages":"277 - 281"},"PeriodicalIF":1.2,"publicationDate":"2025-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144861596","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Acoustic Impulse Response Fluctuations and Coherent Underwater Acoustic Communications in Shallow Water under Autumn Conditions","authors":"A. V. Shatravin","doi":"10.1134/S1063771024602954","DOIUrl":"10.1134/S1063771024602954","url":null,"abstract":"<div><p>The article presents the results of a full-scale experiment aimed at assessing the temporal variability of the impulse response of a hydroacoustic channel and efficiency of coherent underwater acoustic communications using bottom-mounted transmitters and receivers at frequencies of ~10 kHz on the Black Sea shelf in autumn. Three prominent maxima of variable amplitude were observed in the impulse response structure throughout the experiment (~36 h). The range of variability of the root-mean-square decoding error was ~11 dB; the bit error ratio varied from 0 to 0.10. A strong relationship was found between the values of decoding errors and the amplitude of the maximum arrival in the structure of the reference impulse response, corresponding to a group of rays with one reflection off the surface, as well as the coefficient of variation of high-frequency fluctuations of the amplitude of this arrival in the instantaneous estimate of the impulse response. Numerical modeling was used to confirm the hypothesis that in autumn conditions, characterized by the absence of a pronounced seasonal thermocline, the main hydrophysical cause of the variability of the amplitude of the main arrival, and, as a consequence, the effectiveness of underwater acoustic communications, consisted in an insignificant (fractions of a degree) change of temperature in the upper layer of sea water.</p></div>","PeriodicalId":455,"journal":{"name":"Acoustical Physics","volume":"71 2","pages":"223 - 239"},"PeriodicalIF":1.2,"publicationDate":"2025-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144861411","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Vibrational Black Hole for Torsional Waves Propagating through a Rod with a Variable Cross Section","authors":"M. A. Mironov","doi":"10.1134/S1063771025600317","DOIUrl":"10.1134/S1063771025600317","url":null,"abstract":"<p>The propagation of torsional waves through rods with a variable cross section is considered. When the flattening of a rod is linearly increased, the propagation velocity of a torsional wave also linearly decreases to become zero at a finite rod length. Meanwhile, the time of propagation to the sharpened end is equal to infinity. In contemporary terminology, such a decelerating structure is called a vibrational black hole. Exact solutions are found for the equations of torsional vibrations in a sharpened rod with an inertia moment and a torsion moment in the form of power functions along with corresponding expressions for the input impedance at the initial cross section.</p>","PeriodicalId":455,"journal":{"name":"Acoustical Physics","volume":"71 2","pages":"163 - 169"},"PeriodicalIF":1.2,"publicationDate":"2025-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1134/S1063771025600317.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144861570","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Theoretical Analysis of the Influence of Weakly Divergent Beams on the Formation of the Spatiotemporal Structure of Pulse Signals in the Sea of Japan","authors":"Yu. V. Petukhov,&nbsp;E. L. Borodina","doi":"10.1134/S1063771024601754","DOIUrl":"10.1134/S1063771024601754","url":null,"abstract":"<p>Using numerical modeling based on mode theory and the geometric-acoustic approximation, it was determined that in addition to classical quadruples of pulses present in the spatiotemporal field structure, the emergence of additional signals with relatively short delays is caused by the formation of weakly divergent multimode beams in the underwater sound channel of the Sea of Japan; these modes correspond to smooth extrema in the dependences of the spatial interference period of neighboring modes and their group velocity on the mode number. For one of the two sound speed profiles typical of the Sea of Japan, it was shown that at relatively high frequencies, it is possible to receive two groups of additional signals: weakly divergent beams formed by relatively low- and high-order modes.</p>","PeriodicalId":455,"journal":{"name":"Acoustical Physics","volume":"71 2","pages":"216 - 222"},"PeriodicalIF":1.2,"publicationDate":"2025-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144861400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Compensating the Effect of the Displacement of Array Transducers on Tomography Data","authors":"D. I. Zotov,&nbsp;O. D. Rumyantseva","doi":"10.1134/S1063771025600238","DOIUrl":"10.1134/S1063771025600238","url":null,"abstract":"<p>A technique for correcting the fields detected by an array with nonideal placement of transmitting and receiving transducers has been developed and numerically tested. The displacements of the transducers from their ideal positions are preliminarily determined. The correction technique involves finding the angular harmonics based on the fields measured with the displaced transducers. Then these found angular harmonics make it possible to recalculate the fields at ideal positions of the transducers, as well as directly calculate the scattering amplitude. Such corrected data is the input one for the stage of reconstruction of acoustic tomograms, i.e., the internal structure of an object. Numerical simulation has been used to show that in the absence of the correction of the data measured in real conditions, the tomograms can be fractured.</p>","PeriodicalId":455,"journal":{"name":"Acoustical Physics","volume":"71 2","pages":"282 - 299"},"PeriodicalIF":1.2,"publicationDate":"2025-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144861597","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}