Z. Chen, Changzhuan Shao, Xiong Hu, Bing Wang, Daobing Zhang, Xiaomei Tao
{"title":"A Novel Degradation Feature Extraction Technique Based on Improved Base-Scale Entropy","authors":"Z. Chen, Changzhuan Shao, Xiong Hu, Bing Wang, Daobing Zhang, Xiaomei Tao","doi":"10.20855/IJAV.2020.25.11717","DOIUrl":"https://doi.org/10.20855/IJAV.2020.25.11717","url":null,"abstract":"In order to track the performance degradation trend accurately, a novel degradation feature extraction technique is proposed based on improved base-scale entropy. A unified base scale is proposed and a new symbol standard is defined to overcome the disadvantages of the base-scale entropy method, so as to symbolize signal amplitude to characterize information amount under different degradation conditions quantitatively. A lifetime dataset of rolling bearing from the IMS Bearing Experiment Center is introduced. For instance, analysis and some entropy-based techniques including fuzzy entropy, approximate entropy and sample entropy are imported for comparison. The results show that the improved basic-scale technique is able to characterize information amount of the signal amplitude distribution, so that the characterizing performance degradation degree of bearing shows a proportional relationship. When comparing the entropy-based techniques, the improved base-scale entropy technique has a faster calculation speed and better algorithm stability.","PeriodicalId":49185,"journal":{"name":"International Journal of Acoustics and Vibration","volume":"26 1","pages":"41-48"},"PeriodicalIF":1.0,"publicationDate":"2021-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46584878","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Application of Statistical Energy Analysis (SEA) in Estimating Acoustic Response of Panels With Non-Uniform Mass Distribution","authors":"K. Renji","doi":"10.20855/IJAV.2020.25.11736","DOIUrl":"https://doi.org/10.20855/IJAV.2020.25.11736","url":null,"abstract":"Statistical Energy Analysis (SEA) is generally used in estimating the responses of structures to high frequency acoustic excitation. Though it has been successfully applied for panels having uniform mass, its usage is limited when the mass distribution is not uniform, as seen in equipment panels of a spacecraft. Results for such panels are seldom reported. In this work, an attempt is made to address this gap. A methodology to estimate the responses of such panels in SEA framework is presented and demonstrated for an equipment panel of a spacecraft, thus widening its application. This is accomplished through SEA along with the information on the standing waves generated due to the change in the structural properties. The acceleration responses of a typical equipment panel when subjected to a diffused acoustic field in a reverberation chamber are measured. The responses of the same panel are theoretically estimated using the methodology presented and a reasonably good prediction is seen.","PeriodicalId":49185,"journal":{"name":"International Journal of Acoustics and Vibration","volume":"26 1","pages":"80-87"},"PeriodicalIF":1.0,"publicationDate":"2021-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46202794","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Surge Motion Passive Control of TLP with Double Horizontal Tuned Mass Dampers","authors":"M. R. Tabeshpour, Ebrahim Malayjerdi","doi":"10.20855/IJAV.2020.25.11273","DOIUrl":"https://doi.org/10.20855/IJAV.2020.25.11273","url":null,"abstract":"The tension leg platform (TLP) is comprised of a buoyant hull that holds the platform's topside. A group of tendons under the columns connect the TLP to the foundation. The TLP is displaced in six degrees of freedom due to environmental loads. Tendons moor the TLP in vertical direction (heave and pitch). Surge amplitude (horizontal displacement) of TLP is greater than other degrees of freedom. Also heave motion is coupled with surge one. Therefore, it is important to introduce and implement a method to control and reduce displacement of the TLP in horizontal direction. In this paper, a passive control system (double horizontal tuned mass damper (TMD)) is used to mitigate the surge motion of TLP that is under regular waves. Also the efficiency and performance of double horizontal TMD and single horizontal TMD in reduction of surge response is compared.","PeriodicalId":49185,"journal":{"name":"International Journal of Acoustics and Vibration","volume":"26 1","pages":"4-8"},"PeriodicalIF":1.0,"publicationDate":"2021-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42112667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pan Zuofeng, Hou Hangsheng, Lu Wenbo, Jiang Changwei, Du Mintao, Y. Xiang, B. Changan
{"title":"Experimental and Numerical Investigation on the Flow-Induced Interior Noise Based on Pellicular Analysis","authors":"Pan Zuofeng, Hou Hangsheng, Lu Wenbo, Jiang Changwei, Du Mintao, Y. Xiang, B. Changan","doi":"10.20855/IJAV.2020.25.11677","DOIUrl":"https://doi.org/10.20855/IJAV.2020.25.11677","url":null,"abstract":"Turbulence caused by the rearview mirror and A-pillar is the main source of interior wind noise. Because of the difference in energy and transfer efficiency of acoustic and turbulent pressure, it is important to accurately identify the two kinds of pressure on the window surface when studying interior wind noise. Wave Number Decomposition (WND) and Pellicular Mode Decomposition (PMD) are successfully applied to decompose the pressure on the window. Furthermore, the transfer function calculated by pellicular analysis is used to calculate the interior wind noise, and the result is compared with the result calculated by the Finite Element Method (FEM) and measured by the experiment. The results revealed that the interior wind noise calculated by the pellicular analysis method is almost the same as the result calculated by the FEM, and that it presents obvious advantages in computational efficiency.","PeriodicalId":49185,"journal":{"name":"International Journal of Acoustics and Vibration","volume":"26 1","pages":"18-27"},"PeriodicalIF":1.0,"publicationDate":"2021-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45246446","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Obituary Notice: Professor David Newland","authors":"J. Talbot","doi":"10.20855/IJAV.2020.25.1O1","DOIUrl":"https://doi.org/10.20855/IJAV.2020.25.1O1","url":null,"abstract":"","PeriodicalId":49185,"journal":{"name":"International Journal of Acoustics and Vibration","volume":"26 1","pages":"3-3"},"PeriodicalIF":1.0,"publicationDate":"2021-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48551826","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
T. Zhang, Ludi Kang, Xin Li, Hongbo Zhang, Bilong Liu
{"title":"Sound Transmission Prediction of Sandwich Plates With Honeycomb and Foam Cores and an Emphatic Discussion on Radiation Terms","authors":"T. Zhang, Ludi Kang, Xin Li, Hongbo Zhang, Bilong Liu","doi":"10.20855/IJAV.2020.25.11735","DOIUrl":"https://doi.org/10.20855/IJAV.2020.25.11735","url":null,"abstract":"When applying the modal summation method to the sound transmission loss (STL) prediction of various plates, the assumption of the blocked sound pressure, or alternatively speaking, ignoring sound radiation terms, has obvious simplicity and is sometimes used for the single-layered panels, rib-stiffened plates or heavily damped sandwich plates. For light-weighted sandwich plates with honeycomb and foam cores, however, this assumption is somewhat in doubt and worth examining. Based on sixth-order differential equations governing the flexural vibration of sandwich plates, the prediction formula of STL is derived by the modal summation approach. Theoretical predictions were validated by measurement data. Next, the theoretical formula of STL under the assumption of the blocked sound pressure was examined. The STL discrepancies of sandwich plates caused by sound radiation terms are illustrated. It was found that the STL discrepancies of sandwich plates were closely related to frequency, reached their peak value at the coincidence frequency region. The results indicate that the sound radiation terms, or the couplings between the radiated sound pressure and the plate response, should not be ignored for the prediction of STL for sandwich plates with honeycomb and foam cores.","PeriodicalId":49185,"journal":{"name":"International Journal of Acoustics and Vibration","volume":"26 1","pages":"70-79"},"PeriodicalIF":1.0,"publicationDate":"2021-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47604370","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. C. Medeiros, A. Nabarrete, M. Cruchaga, W. R. P. Mendonça, M. H. Mathias
{"title":"Numerical and Experimental Evaluation of Hydrodynamic Bearings Applied to a Jeffcott Test Bench","authors":"E. C. Medeiros, A. Nabarrete, M. Cruchaga, W. R. P. Mendonça, M. H. Mathias","doi":"10.20855/IJAV.2020.25.11732","DOIUrl":"https://doi.org/10.20855/IJAV.2020.25.11732","url":null,"abstract":"Merging analytical and numerical models with experimental results improve the behaviour predictions of mechanical elements applied to rotor machinery, such as the bearings. This work aims to present the design of a hydrodynamic bearing prototype, a comparison and validation between the numerical and experimental results of critical speeds, and the differences of behaviour when the bush geometries and lubrication are changed. The bush geometries and the fluid film properties are analysed by measuring the dynamic behaviour of a rotor supported by these bearings. The experimental evaluation is based on measuring the Jeffcott test bench supported in a pair of bearings, showing the anisotropic behaviour caused by the stiffness difference in horizontal and vertical directions. It also presents an optimization of bushings for isotropic conditions when they were changed for different geometries (elliptical, offset halves) and different materials with boundary lubrication. This detailed study shows how the dynamic behaviour of rotating machinery can be predicted using numerical models and its validation by a test rig. Results also show how the vibration occurs if the bushes geometries are modified or its lubrication condition is changed.","PeriodicalId":49185,"journal":{"name":"International Journal of Acoustics and Vibration","volume":"26 1","pages":"64-69"},"PeriodicalIF":1.0,"publicationDate":"2021-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43129974","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Railways: An Acoustical Point of View","authors":"F. Denia","doi":"10.20855/IJAV.2020.25.1E99","DOIUrl":"https://doi.org/10.20855/IJAV.2020.25.1E99","url":null,"abstract":"","PeriodicalId":49185,"journal":{"name":"International Journal of Acoustics and Vibration","volume":"26 1","pages":"2-2"},"PeriodicalIF":1.0,"publicationDate":"2021-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46292373","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Optimization of Nonlinear Passive Suspension System to Minimize Road Damage for Heavy Goods Vehicle","authors":"Shailendra Kumar, A. Medhavi, Raghuvir Kumar","doi":"10.20855/IJAV.2020.25.11724","DOIUrl":"https://doi.org/10.20855/IJAV.2020.25.11724","url":null,"abstract":"Major contributors to the road damage are Heavy Goods Vehicles (HGV), resulting in high maintenance costs of roads. This high cost makes it necessary to look into the issue seriously for minimizing the road damage. An Automobile Engineer can reduce road damage through the efficient design of a suspension system. The design involves satisfying the two conflicting criteria of riding comfort and vehicle handling with the restriction on the suspension travel. This paper involves designing an automobile suspension system, to improve the performance of the vehicle without a significant change in the cost of the suspension system and minimize road damage. To achieve the aforesaid objective, the use of a nonlinear passive suspension is suitable as compared to a linear passive suspension system. For the analysis, a HGV model of vehicle suspension has been considered. The suspension system considered for investigation comprises of a cubical nonlinear spring and a linear damper. Road damage has been represented by the fourth power of the tire dynamic load. A genetic algorithm has been used to optimize the half truck model to minimize road damage. The solution has been obtained using MATLAB and SIMULINK.","PeriodicalId":49185,"journal":{"name":"International Journal of Acoustics and Vibration","volume":"26 1","pages":"56-63"},"PeriodicalIF":1.0,"publicationDate":"2021-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49159808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Numerical Approach on Hybrid PID-AFC Controller using Different Intelligent Tuning Methods to Reduce the Vibration of the Suspended Handle","authors":"M. Satar, Wong Jen Nyap, A. Mazlan","doi":"10.20855/IJAV.2020.25.11713","DOIUrl":"https://doi.org/10.20855/IJAV.2020.25.11713","url":null,"abstract":"This paper focusses on the study of vibration attenuations for suspended handle models that are generated from power tools using an intelligent active force control (AFC) tuning strategy. Four types of control schemes are comparatively evaluated in suppressing the vibration of the handle, such as proportional-integral-derivative (PID), PID-AFC-crude approximation (AFCCA), PID-AFC-fuzzy logic (AFCFL) and PID-AFC-iterative learning method (AFCILM) control schemes. In all control schemes, the estimated counter force is generated from the actuating force and appropriate estimated mass M* that has been intelligently tuned to counter the system disturbances. The disturbances are modelled based on the power tools vibration (i.e., internal disturbance) and uncertainties during the operation (i.e., external disturbances). The study shows that the AFCCA scheme demonstrates the best performance when the M(CL) is tuned at 0.04 kg. For the AFCFL control scheme, the best response is obtained for the membership function of trapezoidal shape with M(FL) of 0.0403 kg, while for AFCILM control scheme, the best response is achieved when M(ILM) is tuned to 0.04 kg, with both parameters (A and B) set at 0.6. Overall, PID-AFCCA scheme shows the best performances for all of the case studies, followed by PID-AFCFL and PID-AFCILM. The findings of this study can benefit the power tool manufacturers and provide the basis of effectively intelligent controller design for the power tools application.","PeriodicalId":49185,"journal":{"name":"International Journal of Acoustics and Vibration","volume":"26 1","pages":"28-40"},"PeriodicalIF":1.0,"publicationDate":"2021-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48267696","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}