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Flow Induced acoustic resonance in In-line Tube Banks

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Journal of Thermal Science 2006年第3期15卷 226-232页

作者： Hiromitsu Hamakawa Tohru Fukano Eiichi Nishida YoshikazuS atou Department of Mechanical Engineering Oita University 700 Dannoharu Oita 870-1192 Japan Department of Environmental Symbiosis Engineering Kurume Institute of TechnologyKamitsu-machi 2228 Kurume 830-0052 Japan Department of Mechanical Engineering Shonan Institute of Technology Tujido Nishi Kaigan1-1-25 Fujisawa 251-8511 Japan Honda Motor Co. Ltd. Japan

In the present paper the attention is focused on the relation between vortex shedding phenomena and acoustic resonance which occurred in the two-dimensional model of boiler. There were tube banks with in-line arrangement for small tube pitch ratio. We measured the sound pressure level, the phase delay of acoustic pressures, the spectrum of velocity fluctuation and the gap velocity. As a result, we found two peak frequencies of sound pressure level with different Strouhal numbers St, mainly about 0.26 and 0,52, The noise of St=0.26 was the resonance of transverse mode and St=0.52 was longitudinal mode. The vortex shedding of St=0.15 was generated inside the tube banks without acoustic resonance. As gap velocity increased, we observed that the peak level of spectrum was weak and broad-banded, The onset velocity of the acoustic resonance of longitudinal mode was lower than that of transverse mode.

关键词： acoustic resonance flow induced vibration vortex in-line tube banks

Effect of Cavities inside Tube Banks on acoustic resonance

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Journal of Thermal Science 2010年第1期19卷 67-71页

作者： Hiromitsu HAMAKAWA Hidenobu MIYAGI Eiichi NISHIDA Department of Mechanical Engineering Oita University700 DannoharuOita 870-1192Japan Cyuouhatsujyou Kougyou 503 Jyuuni-machiHita877-8501Japan Department of Mechanical Systems Engineering Shonan Institute of Technology1-1-25 Tujidou NisikaiganFujisawa251-8511Japan

In the present paper the attention is focused on the effect of small cavities inside in-line tube banks on acoustic resonance which occurred in the two-dimensional model of boiler. We measured the sound pressure level, the amplitude and the phase delay of acoustic pressures and the gap velocity. As a result, we found many peak frequencies of sound pressure level with different Strouhal numbers, mainly about S1=0.15, 0.26 and 0.52. The variation of SPL for S,=0.26, 0.52 components in the tube banks with cavities was the same as the result of no cavities. The existence of cavities inside in-line tube banks caused the resonance of St=0.15. And the acoustic resonance of the first mode in the transverse direction was generated if the small cavities existed inside the tube banks. This resonance was not generated from the tube banks of no cavities. The resonance onset velocity in the transverse mode was fairly slower than that of no cavities. It was easy to generate acoustic resonance when there were small cavities inside in-line tube banks.

关键词： acoustic resonance Flow Induced Noise In-line Tube Banks Cavity Boiler

Wireless Electricity Transmission（using acoustic resonance through piezoelectric crystals）

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Wireless Electricity Transmission（using acoustic resonance ...

Experimental study of rotor blades vibration and noise in multistage high pressure compressor and their relevance

International Conference on Computational Techniques and Artificial Intelligence(ICCTAI’2011);International Conference on Advances in Electrical and Electronics Engineering(ICAEE’2011);International Conference on Mechanical,Automobile and Robotics Engineering(ICMAR’2011);International Conference on Management,Behavioral Sciences and Economics Issues(ICMBSE’2011);International Conference on Chemical,Environmental and Biological Sciences(ICCEBS’2011);International Conference on Biotechnology and Pharmaceutical Sciences(ICBPS’2011)

作者： Prabhat Ranjan Tripathi Abdullah Khan Electrical and Electronics Engineering SRM Institute of Science and Technology SRM University

This paper presents an idea of wireless electric power transmission through piezoelectric crystals by acoustic resonance. This will prove to be a boon to the present era where wireless data transmission technologies are commonly used in electronic devices. We need to connect them to wired devices for powering them, which at times becomes irritating and lossy as they use batteries which need recharging, replacements and maintenance. So to provide solution to this problem, wireless electricity transmission is the best way which not only promises the seamless power availability but also ensures the power conservation by minimizing the transmission losses which occur in wired arrangements. Wireless electric power transmission can be achieved by many ways such as coupled magnetic resonance, laser, microwaves etc. The proposed work recommends use of acoustic resonance in piezoelectric crystals by virtue of their property of piezoelectricity and inverse piezoelectricity.

关键词： acoustic resonance inverse piezoelectricity piezoelectricity ultrasound.

来源： cnki会议评论

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Chinese Journal of Aeronautics 2020年第3期33卷 870-878页

作者： Fengtong ZHAO Xiaodong JING Mingsui YANG Deyou WANG Yundong SHA Xiaochi LUAN School of Energy and Power Engineering Beihang UniversityBeijing 100191China Liaoning Province Key Laboratory of Advanced Measurement And Test Technology of Aviation Propulsion Systems Shenyang Aerospace UniversityShenyang 110136China Shenyang Engine Design and Research Institute Aero Engine(Group)Corporation of ChinaShenyang 110015China

Rotor blades fault of aeroengine compressor is mostly caused by mechanical and aerodynamic *** the excitation factor of high intensity sound wave to rotor blades should not be *** researches are conducted on a multistage high pressure *** high level vibration occurs on the first stage of rotor blades, the noise spectrum presents typical characteristic for discrete multi-tone in the *** amplitude of blade vibration displacement and the sound pressure level of characteristic frequency noise increases and decreases simultaneously and reaches the maximum value at the same *** frequency merely occur on a certain speed range and is locked in a specific range which presents no variation with the rotating *** high level vibration occurs on the first stage of rotor blades, the noise spectrum presents a sharp peak and the propagation state of the characteristic frequency is a helix structure in the *** can be confirmed that acoustic resonance occurs in the multistage *** acoustic resonance frequency and its side band frequencies are generated by modulation of a rotating noise source at the rotor speed which is the excitation source of the rotor blades vibration.

关键词： acoustic resonance Blades vibration Characteristic frequency Multistage compressor Source identification

3D Characteristic Diagram of acoustically Induced Surface Vibration with Different Landmines Buried

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Transactions of Tianjin University 2016年第4期22卷 367-373页

作者：吴智强张燕丽王驰朱俊徐文文袁志文 Department of Precision Mechanical Engineering Shanghai UniversityShanghai 200072China North Automatic Control Technology Research Institute Taiyuan 030006China Science and Technology on Near-Surface Detection Laboratory Wuxi 214035China State Key Laboratory of Precision Measuring Technology and Instruments Tianjin UniversityTianjin 300072China Shanghai Public Utility School Shanghai 200030China

The 3D characteristic diagram of acoustically induced surface vibration was employed to study the influence of different buried landmines on the acoustic detection signal. By using the vehicular experimental system for acoustic landmine detection and the method of scanning detection, the 3D characteristic diagrams of surface vibration were measured when different objects were buried underground, including big plastic landmine, small plastic landmine, big metal landmine and bricks. The results show that, under the given conditions, the surface vibration amplitudes of big plastic landmine, big metal landmine, small plastic landmine and bricks decrease in turn. The 3D characteristic diagrams of surface vibration can be used to further identify the locations of buried landmines.

关键词： acoustic-to-seismic(A/S) coupling acoustic landmine detection acoustic resonance surface vibration velocity