NOISE-CON ... proceedings最新文献_第2页

Degradation and damage analysis of composite pressure vessels via experimental modal analysis 基于试验模态分析的复合材料压力容器退化与损伤分析

NOISE-CON ... proceedings Pub Date : 2023-11-05 DOI: 10.3397/no_2023_0057

Sebastian John

{"title":"Degradation and damage analysis of composite pressure vessels via experimental modal analysis","authors":"Sebastian John","doi":"10.3397/no_2023_0057","DOIUrl":"https://doi.org/10.3397/no_2023_0057","url":null,"abstract":"For mobile gas storage systems, the application of type IV pressure vessels is state of the art. Type IV tanks consist of an inner polymer liner fully wrapped with fibre-reinforced plastic (FRP). Because of the complex fabric of the FRP as well as a difficulty estimable interaction behaviour between the single components under load, there are still no satisfying non-destructive testing methods to assess the current state of failure nor to estimate the level of degradation accurately and economically. At BAM division 3.5, analysing the ageing process of mobile composite pressure vessels is a major task to ensure safe usage over the whole lifetime. In this context, key aspects of our ongoing research activities are the invention of new test procedures and the development of accurate lifetime prediction models. In order to determine the level of degradation or damage, one meaningful non-destructive approach is to analyse the structural dynamic behaviour via an experimental modal analysis (EMA). Over the last few years, different types and sizes of composite pressure vessels have been tested in several research projects. The presented paper gives an insight into how to extract and interpret modal parameters and how to fit them to the results of residual strength tests.","PeriodicalId":471330,"journal":{"name":"NOISE-CON ... proceedings","volume":"33 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135725646","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

Sensitivity and bifurcation analysis of an analytical model of a trapped object in an externally excited acoustic radiation force field 外激发声辐射力场中被困物体解析模型的灵敏度和分岔分析

NOISE-CON ... proceedings Pub Date : 2023-11-05 DOI: 10.3397/no_2023_0012

Mehdi Akbarzadeh

引用次数: 0

Uncertainty quantification of the diffuse sound field assumption in sound insulation predictions 隔声预测中弥漫声场假设的不确定性量化

NOISE-CON ... proceedings Pub Date : 2023-11-05 DOI: 10.3397/no_2023_0114

Reynders Edwin

{"title":"Uncertainty quantification of the diffuse sound field assumption in sound insulation predictions","authors":"Reynders Edwin","doi":"10.3397/no_2023_0114","DOIUrl":"https://doi.org/10.3397/no_2023_0114","url":null,"abstract":"The transmission loss of a partition depends on the sound fields in the adjoining rooms, which are often taken to be diffuse. A diffuse sound field is a random field, representing a conceptual ensemble of rooms with the same volume and reverberation time, but otherwise any possible arrangement of boundaries and small objects that have a wave scattering effect. Uncertainty due to random wave scattering is therefore inherently present in diffuse transmission loss values. In this work, closed-form expressions are presented for quantifying this uncertainty, such that it becomes possible to estimate by how much the transmission loss of a particular room-wall-room system may deviate from the nominal, ensemble average value which corresponds to omnidirectional incidence and halfspace radiation. The first expression is exact yet its evaluation requires knowledge of the dynamic stiffness of the partitioning structure and of the radiation impedances of the surrounding fluids. The second expression is approximate and depends on energetic quantities only, so it is also applicable in an experimental setting. The expressions are validated in a Monte-Carlo simulation study involving a single wall.","PeriodicalId":471330,"journal":{"name":"NOISE-CON ... proceedings","volume":"34 11","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135726946","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

On the modeling of thin moving sound sources using a cutFEM approach 基于切削有限元法的薄型运动声源建模研究

NOISE-CON ... proceedings Pub Date : 2023-11-05 DOI: 10.3397/no_2023_0105

Sjoerd van Ophem

{"title":"On the modeling of thin moving sound sources using a cutFEM approach","authors":"Sjoerd van Ophem","doi":"10.3397/no_2023_0105","DOIUrl":"https://doi.org/10.3397/no_2023_0105","url":null,"abstract":"While for vibro-acoustic analysis it is often assumed that the source is stationary, in many situations it is moving. Thus, to accurately determine the acoustic response of these systems, a time-varying system has to be solved. This leads to additional challenges, such as how to deal with the varying geometrical configuration and choosing an appropriate time-stepper. Recently, it was shown that cut finite elements (cutFEM) might be a viable solution, since this approach uses a stationary background mesh and cuts the elements wherever the moving source is located, thus omitting remeshing and mesh morphing steps. In this contribution, the approach is extended to also include the possibility to model thin sources (plates/shells), which are a common cause for noise radiation in structures. This is a non-trivial extension, since an immersed thin source leads to a discontinuity in the pressure response among the cut and a local doubling of the elements to capture the pressure on both sides of the cut. This paper describes how to perform numerical integration on the cut elements, how to apply stabilization, and shows a stable time-integration scheme to calculate the solution. It concludes by showing an example of a moving line source.","PeriodicalId":471330,"journal":{"name":"NOISE-CON ... proceedings","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135726956","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

Near-field modeling of the head-related transfer function by using the dummy head sound source 利用假头声源对头部相关传递函数进行近场建模

NOISE-CON ... proceedings Pub Date : 2023-11-05 DOI: 10.3397/no_2023_0111

Wan-Ho Cho

{"title":"Near-field modeling of the head-related transfer function by using the dummy head sound source","authors":"Wan-Ho Cho","doi":"10.3397/no_2023_0111","DOIUrl":"https://doi.org/10.3397/no_2023_0111","url":null,"abstract":"Various approaches based on direct measurement have been used to obtain the precise headrelated transfer function (HRTF). However, several problems persist, such as scattering of sound source and distance effect, which are related to the measurement configuration. In this work, the modified dummy head having two sound sources located at the ear positions is applied as the sound source reciprocally to overcome the trouble. By using the near-field acoustic holography, the sound sources located in the ear holes are reconstructed from the measured data in the near-field hologram. One can predict the acoustic transfer function between the ear holes and the field positions at any point using the recovered source information described in spherical harmonics. The obtained transfer function is valid for predicting the binaural response from any sound source position. This configuration is possible to measure the near-field response with the relatively small scattering effect because of the low Helmholtz number of microphones. The far-field reconstruction of HRTF is also possible with the near-field measurement data using acoustical holography. The proposed method is demonstrated with the modified B&K HATS system, in which the microphones in the ear holes are replaced by pipe sources connected to the loudspeaker.","PeriodicalId":471330,"journal":{"name":"NOISE-CON ... proceedings","volume":"32 5","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135728279","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

Control of chaotic vibrations in lumped mass models of the vocal folds 声带集中质量模型中混沌振动的控制

NOISE-CON ... proceedings Pub Date : 2023-11-05 DOI: 10.3397/no_2023_0046

Oriol Guasch

引用次数: 0

Reconstruction of Substructural Transfer Functions with Operational Responses Using Deep Learning Approach 用深度学习方法重建具有操作响应的子结构传递函数

NOISE-CON ... proceedings Pub Date : 2023-11-05 DOI: 10.3397/no_2023_0079

Dooho Lee

引用次数: 0

Acoustic Performance of a Metamaterial Coating with Uncertainty in Design Parameters 设计参数不确定的超材料涂层声学性能研究

NOISE-CON ... proceedings Pub Date : 2023-11-05 DOI: 10.3397/no_2023_0093

Karthik Modur

引用次数: 0

Evolutionary strategy to optimize sonic black hole profiles in duct terminations 优化管道末端声波黑洞轮廓的进化策略

NOISE-CON ... proceedings Pub Date : 2023-11-05 DOI: 10.3397/no_2023_0047

Oriol Guasch

{"title":"Evolutionary strategy to optimize sonic black hole profiles in duct terminations","authors":"Oriol Guasch","doi":"10.3397/no_2023_0047","DOIUrl":"https://doi.org/10.3397/no_2023_0047","url":null,"abstract":"Sonic black holes (SBH) at duct ends constitute a particular type of anechoic termination. Acoustic waves get slowed down by means of a set of rings separated by cavities, whose inner radii diminish following a power law. Ideally, such design produces no wave reflection. In practice, however, this is not possible though the reflection coefficient remains low for a broadband frequency range. In this work, an evolutionary strategy (ES) is used to optimize the shape of SBH profiles and to try to improve the results of the standard power-law design. We test several cost functions for the reflection coefficient and impose constraints on the radii to fasten convergence. Different optimization problems are addressed. The first one is to determine the optimum exponent for the classical power-law profile. In the second one, the inner ring radii are only imposed to be monotonically decreasing from the SBH entrance. This results in new designs that overcome the performance of the optimum power-law profile at almost all frequencies. To perform the computations, we use a transfer matrix method for the SBH and resort to a derandomized ES with covariance matrix adaptation, which can easily deal with multiobjective optimization at a very reasonable computational cost.","PeriodicalId":471330,"journal":{"name":"NOISE-CON ... proceedings","volume":"35 8","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135725922","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

Bloch mode synthesis for band-structure computation of unit cell with non-matching boundaries 非匹配边界单晶带结构计算的布洛赫模式综合

NOISE-CON ... proceedings Pub Date : 2023-11-05 DOI: 10.3397/no_2023_0084

Chenyang Xi

引用次数: 0