Volume 1: Acoustics, Vibration, and Phononics最新文献

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Measurements of Pulsation Generated Due to Turning Flow Into Side Branches of Different Diameter Ratios 不同径比的侧支路转流产生脉动的测量
Volume 1: Acoustics, Vibration, and Phononics Pub Date : 2021-11-01 DOI: 10.1115/imece2021-69111
K. Botros, H. Satish
{"title":"Measurements of Pulsation Generated Due to Turning Flow Into Side Branches of Different Diameter Ratios","authors":"K. Botros, H. Satish","doi":"10.1115/imece2021-69111","DOIUrl":"https://doi.org/10.1115/imece2021-69111","url":null,"abstract":"\u0000 The present investigation was motivated by a noticeable high-pressure pulsations and vibrations during commissioning of a centrifugal compressor on a high-pressure natural gas transmission system. During commissioning, the gas from the compressor discharge is recycled back to compressor inlet through a recycle line turning the gas flow from the main discharge line into a smaller diameter side branch, thus creating a deadleg due to the closure of a check valve farther downstream on the main discharge line. To better understand and characterize the flow generated pulsations due turning flow into side branches, an experimental setup was constructed on ambient air to test three side-branch to main pipe diameter ratios (d/D), nominally: 1.0, 0.75 and 0.5, over a wide range of mean flow velocities. Experimental results of the normalized pulsation pressure amplitudes (P*) vs. Strouhal number characterized the flow-acoustic field for the three d/D ratios and for acoustically tuned and detuned systems. It was found that P* decreases as d/D decreases for acoustically tuned systems. The highest P* was achieved with d/D = 1 which reached a value of 3.543 at St = 0.1376. At lower d/D = 0.762, the maximum value of P* decreased to 1.173 at a slightly lower St number of approximately 0.1. In the case of d/D = 0.5132, the normalized pressure P* was further reduced to a very low value of 0.2462 at a wider range of St number. Acoustically tuned system is characterized by having the highest anti-nodal point of acoustic velocity oscillation at the Tee-junction location in the axial direction of the main pipe, with minimum acoustic leakage into the side branch. When the system is acoustically detuned, i.e., when the axial acoustic velocity oscillations at the Tee-junction is reduced, the strength of the local acoustic source at the junction is also reduced resulting in a lower peak normalized pressure amplitude at the deadleg. The peak amplitudes of pressure pulsations occur at frequencies exactly matching the deadleg 1/4 wavelength resonance, whether it is tuned or detuned with respect to the inlet section. That is, the peak frequencies tracked the changes in the deadleg length and was not influenced by the inlet section acoustic resonance characteristics. This led to the postulation that the main driver of the flow-generated pulsations, i.e., the acoustic source is associated with the high-shear area of the flow facing the deadleg at the trailing edge of the Tee-junction rather than the ‘vortex bubble’ due to flow separation at the leading edge of the side branch.","PeriodicalId":23648,"journal":{"name":"Volume 1: Acoustics, Vibration, and Phononics","volume":"65 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84466965","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Real-Time Sound Source Localization Using a Parabolic Reflector 使用抛物面反射器的实时声源定位
Volume 1: Acoustics, Vibration, and Phononics Pub Date : 2021-11-01 DOI: 10.1115/imece2021-70385
Chang Liu, Xu Mao, Chang Wang, J. Heredia Juesas, J. Martinez-Lorenzo
{"title":"Real-Time Sound Source Localization Using a Parabolic Reflector","authors":"Chang Liu, Xu Mao, Chang Wang, J. Heredia Juesas, J. Martinez-Lorenzo","doi":"10.1115/imece2021-70385","DOIUrl":"https://doi.org/10.1115/imece2021-70385","url":null,"abstract":"\u0000 Contrary to the active detection methods, the passive sound source localization technologies only rely on the differences among the signals recorded by different receivers to localize the object generating the sound wave, without the knowledge of the sound source profile and excitation time. Time domain investigation methods have been widely applied in the analysis of sound source tracking, which greatly suffers from the high ambient noise problems. Instead, this paper applies an imaging method based on frequency domain cross-coherence (FDCC) operation to reconstruct the source to alleviate the effect of noise. The experimental results show the reliability of this method to recover the source in 3D. Moreover, a parabolic reflector is proposed to further increase the measurement amplitude and signal to noise ratio. The FDCC method successfully localizes the source even if the propagation path of the sound wave is disturbed by the reflector.","PeriodicalId":23648,"journal":{"name":"Volume 1: Acoustics, Vibration, and Phononics","volume":"8 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83195825","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Effect of Coupled Helmholtz Resonators on Sound Control 耦合亥姆霍兹谐振器对声音控制的影响
Volume 1: Acoustics, Vibration, and Phononics Pub Date : 2021-11-01 DOI: 10.1115/imece2021-70333
R. Sabat, G. Leveque, Y. Pennec, D. Torrent, B. Djafari-Rouhani
{"title":"Effect of Coupled Helmholtz Resonators on Sound Control","authors":"R. Sabat, G. Leveque, Y. Pennec, D. Torrent, B. Djafari-Rouhani","doi":"10.1115/imece2021-70333","DOIUrl":"https://doi.org/10.1115/imece2021-70333","url":null,"abstract":"\u0000 In our work, we are interested in the effect of coupling between Helmholtz resonators using the finite element model. We show that the coupling between two spheres leads to two peaks of resonance at low frequencies. One of them is symmetric and corresponds to a mono-polar breathing mode. The second one is anti-symmetric and behaves like a dipole. Consequently, the first one produces an isotropic wave in the far pressure field, while the second produces a directional propagation wave. Therefore, by changing the distance and / or the orientation between the resonators, we aim to manipulate and control the direction of the acoustic wave at specific frequencies.","PeriodicalId":23648,"journal":{"name":"Volume 1: Acoustics, Vibration, and Phononics","volume":"8 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82286397","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Research on Tone Quality for Vehicles Considering the Masking Effect 考虑掩蔽效应的车辆音质研究
Volume 1: Acoustics, Vibration, and Phononics Pub Date : 2021-11-01 DOI: 10.1115/imece2021-72907
Jiewei Lin, Rui Zhang, Qidi Zhou, Junhong Zhang, Gengyi Lin
{"title":"Research on Tone Quality for Vehicles Considering the Masking Effect","authors":"Jiewei Lin, Rui Zhang, Qidi Zhou, Junhong Zhang, Gengyi Lin","doi":"10.1115/imece2021-72907","DOIUrl":"https://doi.org/10.1115/imece2021-72907","url":null,"abstract":"\u0000 Sound quality (SQ) plays important role in automobile competitiveness, in which the high frequency characteristics of tones are prominent when internal combustion engines are replaced by fuel cells or batteries. Hence, it is of great significance to explore the influence of tones on the SQ of such electric vehicles. At the moment, the prominence of tones is concerned but the influence of tones in different frequency ranges is not comprehensively considered. Meanwhile, there are some researches on the masking effect of background noise, but they are insufficient. To address these issues, the SQs of four types of vehicles (van, SUV, pure electric car, fuel cell heavy truck) are studied. The prominence ratio (PR) is found to be effective in the evaluation of tones SQ. The influence of tones on subjective evaluation is explored from two dimensions of “audible” and “irritable”. The results show that whether tones can be “audible” and “irritable” are related to the masking effect of background noise and the frequency distribution. Meanwhile, the PR limits of tones are obtained in different frequencies under various working conditions and operating modes.","PeriodicalId":23648,"journal":{"name":"Volume 1: Acoustics, Vibration, and Phononics","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82899963","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Statistical Energy Analysis of Vibrating Structures With Energy and Entropy 具有能量和熵的振动结构的统计能量分析
Volume 1: Acoustics, Vibration, and Phononics Pub Date : 2021-11-01 DOI: 10.1115/imece2021-69640
Elise M. Hough, Z. Sotoudeh
{"title":"Statistical Energy Analysis of Vibrating Structures With Energy and Entropy","authors":"Elise M. Hough, Z. Sotoudeh","doi":"10.1115/imece2021-69640","DOIUrl":"https://doi.org/10.1115/imece2021-69640","url":null,"abstract":"\u0000 We present a complete thermodynamic analogy of statistical energy analysis (SEA) using entropy and energy for both linear and nonlinear coupled systems. We will use Khinchin’s Entropy as our statistical entropy definition from statistical mechanics. This framework allows for the restrictive assumptions of linearity to be removed from this analysis method. We will use the classical definition of entropy to relate entropy to Vibrational Temperature. Using Khinchin’s statistical definition of entropy for a vibrating system, we will define a Vibrational Temperature as a function of energy. Hence, we will derive all that is necessary to construct the SEA power flow equation along with the transient coupling loss factors without any linearity assumption. With this method one can expand SEA to nonlinear transient coupled systems. We will verify our proposed method using Monte Carlo Simulation and published analytical closed form solutions.","PeriodicalId":23648,"journal":{"name":"Volume 1: Acoustics, Vibration, and Phononics","volume":"28 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90045722","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Numerical Modal Sensitivity Analysis for Fatigue Damage Accumulation in Adhesively Bonded Lap-Joint 粘接搭接疲劳损伤累积的数值模态敏感性分析
Volume 1: Acoustics, Vibration, and Phononics Pub Date : 2021-11-01 DOI: 10.1115/imece2021-73587
R. Palanisamy, P. Banerjee, M. Haq, Y. Deng
{"title":"Numerical Modal Sensitivity Analysis for Fatigue Damage Accumulation in Adhesively Bonded Lap-Joint","authors":"R. Palanisamy, P. Banerjee, M. Haq, Y. Deng","doi":"10.1115/imece2021-73587","DOIUrl":"https://doi.org/10.1115/imece2021-73587","url":null,"abstract":"\u0000 Adhesively bonded joints are gaining popularity among automotive industries due to their light-weight, cost-effective, and multi-material joining solutions. Adhesively bonded joints not only yield light-weighted structures but also provide a more uniform stress distribution than riveted joints resulting in higher fatigue life. However, due to their complex damage mechanism it is not easy to analytically predict the transition between crack initiation, propagation and failure of the joint. To improve the confidence of crack detection and estimation in adhesively bonded lap-joint, this paper proposes a numerical guided wave modal analysis to better understand the fatigue damage. From initial experiments it was found that the crack inside adhesive lap-joints increases at different rates depending on the state of the damage and can be modelled according to the paris-paris law. However, accurate estimation of the transition from crack initiation and crack propagation until total failure is non-trivial. In this paper, a series of finite element simulations are conducted to understand the modal behavior of guided waves at various damage states of the lap-joint and extract the most useful features indicative of transition form from crack initiation and crack propagation. Extracted features shall be used in various prognosis models to improve the remaining-useful-life prediction.","PeriodicalId":23648,"journal":{"name":"Volume 1: Acoustics, Vibration, and Phononics","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89173939","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Corrosion Monitoring and Mitigation in Reinforced Concrete Structures Using Novel 3D-Printed Valves and Internet-of-Things Approach 使用新型3d打印阀门和物联网方法的钢筋混凝土结构腐蚀监测和缓解
Volume 1: Acoustics, Vibration, and Phononics Pub Date : 2021-11-01 DOI: 10.1115/imece2021-72141
Mario Escarcega, Savannah Bradley, Gabriel Campos, Parker Randall, Luke Strebe, Hamed Momeni, A. Ebrahimkhanlou
{"title":"Corrosion Monitoring and Mitigation in Reinforced Concrete Structures Using Novel 3D-Printed Valves and Internet-of-Things Approach","authors":"Mario Escarcega, Savannah Bradley, Gabriel Campos, Parker Randall, Luke Strebe, Hamed Momeni, A. Ebrahimkhanlou","doi":"10.1115/imece2021-72141","DOIUrl":"https://doi.org/10.1115/imece2021-72141","url":null,"abstract":"\u0000 Reinforced concrete corrosion can be monitored by the acoustic emissions produced by transient mechanical waves of corrosion and damage events. This study aims to use 3D-printed one-way valves to relieve the corrosion-induced internal pressure on concrete structures. This valve is designed in such a way that it can be simply installed to existing structures to increase corrosion resistance in the concrete structure and extend the service life. The impressed current technique is a common technique used to rapidly corrode reinforced concrete samples. To corrode the concrete samples, current was passed through the internal steel strand and copper mesh. This study also investigated the use of an Internet-of-Things device to continuously monitor corrosion in steel-reinforced concrete samples in order to determine the effectiveness of the designed valves. Pressure testing revealed that the designed valves were against backflow and cracked at very low pressure. It was ideal that the valves cracked at a lower pressure so as to release pressure constantly while preventing further corrosion in backflow. This type of valve will prevent reinforced concrete surface cracking and extend the service life of concrete structures by releasing internal pressure build-up without allowing foreign materials to further corrode the steel reinforcement.","PeriodicalId":23648,"journal":{"name":"Volume 1: Acoustics, Vibration, and Phononics","volume":"27 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73766262","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Spatial Localization of Air Inclusions in Carbon Fiber T-Beam, by Use of Wavelet Entropy Time Series From Hammer Tap Test 基于小波熵时间序列的碳纤维t梁空气夹杂物空间定位
Volume 1: Acoustics, Vibration, and Phononics Pub Date : 2021-11-01 DOI: 10.1115/imece2021-67591
Spyridon Brouzas, I. Georgiou
{"title":"Spatial Localization of Air Inclusions in Carbon Fiber T-Beam, by Use of Wavelet Entropy Time Series From Hammer Tap Test","authors":"Spyridon Brouzas, I. Georgiou","doi":"10.1115/imece2021-67591","DOIUrl":"https://doi.org/10.1115/imece2021-67591","url":null,"abstract":"\u0000 In this paper, a vibration-based method, called wavelet entropy time series, for non-destructive testing of carbon fiber specimens is introduced and demonstrated experimentally. The wavelet transform of vibration signals, acquired after an impact excitation of the specimen, is combined with Shannon’s informational entropy to quantify a trend in the disorder of the signal. Notions such as wavelet entropy, wavelet entropy time series are defined and utilized to assist in structural health monitoring. The scientific merit of the method was investigated both experimentally and computationally. Wavelet entropy time series was able to identify patterns in the complexity of signals making the method suitable for other signal processing applications, outside the scope of non-destructive testing.","PeriodicalId":23648,"journal":{"name":"Volume 1: Acoustics, Vibration, and Phononics","volume":"59 Pt A 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74059599","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
High-Damping Viscoelastic Material Monitoring Using Sub-Resonator Enhanced Electro-Mechanical Impedance Spectroscopy 基于子谐振腔增强电-机械阻抗谱的高阻尼粘弹性材料监测
Volume 1: Acoustics, Vibration, and Phononics Pub Date : 2021-11-01 DOI: 10.1115/imece2021-71172
Runye Lu, Yanfeng Shen
{"title":"High-Damping Viscoelastic Material Monitoring Using Sub-Resonator Enhanced Electro-Mechanical Impedance Spectroscopy","authors":"Runye Lu, Yanfeng Shen","doi":"10.1115/imece2021-71172","DOIUrl":"https://doi.org/10.1115/imece2021-71172","url":null,"abstract":"\u0000 This paper presents the Electromechanical Impedance Spectroscopy (EMIS) method employing a novel piezoelectric wafer active sensor (PWAS) with sub-resonators, which can generate additional resonant peaks to enhance the impedance signature. In order to develop an in-depth understanding of the mechanism behind the sub-resonator effects, an analytical investigation is conducted first. The theoretical solution for the impedance of the new sub-resonator PWAS transducer is derived. Furthermore, numerical simulations are carried out to demonstrate the effectiveness of the new transducer to create additional resonant peaks. Harmonic analysis of coupled field finite element (FEM) models is conducted. Material degradations are modeled by altering the material properties like density and elastic modulus. Comparative investigations are carried out with both conventional PWAS transducers and sub-resonator PWAS transducers. EMI damage indices based on the spectral amplitude and frequency variation features are used to quantify the material degradation and simultaneously prove the superiority of the sub-resonator PWAS over the conventional PWAS. Additionally, a high-damping dog-bone specimen is employed to conduct the creep experiment lasting for twenty-four hours with a recording interval of two hours. The impedance spectra are obtained by the Bode-100 impedance analyzer. The experimental results further demonstrate the improved sensitivity of the sub-resonator transducer, which is in good agreement with the theoretical and numerical findings. The paper finishes with summary, concluding remarks, and suggestions for future work.","PeriodicalId":23648,"journal":{"name":"Volume 1: Acoustics, Vibration, and Phononics","volume":"53 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74578937","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Implementation of Triply Poly Minimal Surfaces in Design of Phononic Crystals and Acoustic Metamaterials 三聚极小面在声子晶体及声学超材料设计中的应用
Volume 1: Acoustics, Vibration, and Phononics Pub Date : 2021-11-01 DOI: 10.1115/imece2021-72624
Daniel Saatchi, I. Oh
{"title":"Implementation of Triply Poly Minimal Surfaces in Design of Phononic Crystals and Acoustic Metamaterials","authors":"Daniel Saatchi, I. Oh","doi":"10.1115/imece2021-72624","DOIUrl":"https://doi.org/10.1115/imece2021-72624","url":null,"abstract":"\u0000 Triply Poly Minimal Surfaces (TPMS) are three dimensional periodic lattice structures with a trigonometric relationship in their unit cell that can be implemented for acoustic applications including acoustic metamaterials and Phononic crystals. The necessity and demand in the ultrasound and acoustic industry for new materials pave the way to investigate further mechanical wave research into the different shape of engineered metamaterials that usually does not exist in nature for different purposes. This paper presents a design pipeline for Schwarz Primitive acoustic metamaterial from the mathematically driven stage of computational design of the unit cell with the utilization of finite element method to simulate the Phononic bandgaps, acoustic pressure, wave propagations, sound pressure levels, and sound transmission loss. The effect of periodic, Floquet, symmetry, & dipole boundary conditions as well as the effect of the upstream and downstream numerical domain extension on the final transmission loss signal in the simulations are compared. These numerical evaluations are important for future experimental acoustic measurement in the different impedance tubes with different microphone positions and sample setups. Finally, the initial stage of additive manufacturing using Stereolithography 3D printing technology for the fabrication of TPMS sample to compare the numerical data with experimental acoustic data is addressed as well as its potential applications to use in the different industries.","PeriodicalId":23648,"journal":{"name":"Volume 1: Acoustics, Vibration, and Phononics","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79246451","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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