Flow-Induced Vibration Study of Tunnel Spillway Working Gate on One Reservoir

In order to study the flow-induced vibration of the spillway tunnel working gate of one reservoir, hydraulic model test with scale 1:20 was conducted to obtain the dynamic pressure characteristics on the working gate. Experiment modal analysis method was employed to identify the structure dynamic characteristics through the 1:10 working gate mode test. The 3D FEM model of the gate was built to simulate the vibration response of the structure. The research showed the low order modal frequencies of the working gate were not fully breaking away from the high energy zone of the dynamic water, which would induce severe vibration. The vibration response of the gate became the biggest when it was operating at 0.5 partial opening.

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Seismic Response Analysis of Tower Crane in Consideration of the Building-Crane Interaction

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.353-356.1981 ◽

2013 ◽

Vol 353-356 ◽

pp. 1981-1985 ◽

Cited By ~ 2

Author(s):

Bing Ai ◽

Jia Lin Yang ◽

Zeng Zhuang Pei

Keyword(s):

Seismic Response ◽

Seismic Analysis ◽

Dynamic Responses ◽

Response Analysis ◽

Analysis Method ◽

Ansys Software ◽

Seismic Response Analysis ◽

3D Fem ◽

Fem Model ◽

Tower Crane

Interaction between buildings and tower has not been considered in former research..In this paper an integrated seismic analysis method is proposed considering the interaction between the building and the tower crane. A 3D-FEM model of the building and the crane is established with ANSYS software and seismic responses such as the displacement, the acceleration and the stress of the crane are analyzed. The sensitivity of the stiffness of the building on the dynamic responses is also analyzed. The results with consideration of the building-crane interaction, is higher than the results without interaction, and it becomes more significant with the increase of stiffness of the building.

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3D FEM model to simulate Brownian motion inside trabecular tissue from human femoral head

Computer Methods in Biomechanics and Biomedical Engineering Imaging & Visualization ◽

10.1080/21681163.2021.1956370 ◽

2021 ◽

pp. 1-8

Author(s):

Fabiano Bini ◽

Andrada Pica ◽

Simone Novelli ◽

Raffaella Pecci ◽

Rossella Bedini ◽

...

Keyword(s):

Brownian Motion ◽

Femoral Head ◽

3D Fem ◽

Fem Model

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High-Frequency Vibration Response of Metal Honeycomb Sandwich Structure

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.79-82.1727 ◽

2009 ◽

Vol 79-82 ◽

pp. 1727-1730 ◽

Cited By ~ 1

Author(s):

Xiao Dong He ◽

Xiang Hao Kong ◽

Li Ping Shi ◽

Ming Wei Li

Keyword(s):

High Frequency ◽

Sandwich Structure ◽

Dynamic Pressure ◽

Vibration Response ◽

Element Analysis ◽

High Frequency Vibration ◽

Honeycomb Sandwich ◽

Vibration Experiment ◽

Aerial Vehicle ◽

Honeycomb Sandwich Structure

ARMOR TPS panel is above the whole ARMOR TPS, and the metal honeycomb sandwich structure is the surface of the ARMOR TPS panel. So the metal honeycomb sandwich structure plays an important role in the ARMOR TPS, while it bears the flight dynamic pressure and stands against the flight dynamic calefaction. So the active environment of metal honeycomb sandwich structure is very formidable. We have to discuss any extreme situation, for reason of making sure aerial vehicle is safe. And high-frequency vibration is one of active environment. In this paper we have analyzed high-frequency vibration response of metal honeycomb sandwich structure. We processed high-frequency vibration experiment by simulating true aerial environment. Sequentially we operated high-frequency vibration experiment of metal honeycomb sandwich structure with cracks, notches and holes. Then finite-element analysis was performed by way of validating the experiment results. Haynes214 is a good high temperature alloy material of both face sheet and core at present, so we choose it in this paper.

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Flow-Induced Vibration in Subsea Jumper Subject to Downstream Slug and Ocean Current

Journal of Offshore Mechanics and Arctic Engineering ◽

10.1115/1.4032225 ◽

2016 ◽

Vol 138 (2) ◽

Cited By ~ 5

Author(s):

Yaojun Lu ◽

Chun Liang ◽

Juan J. Manzano-Ruiz ◽

Kalyana Janardhanan ◽

Yeong-Yan Perng

Keyword(s):

Modal Analysis ◽

Dominant Role ◽

Production Equipment ◽

Vibration Response ◽

Ocean Current ◽

Flow Assurance ◽

Production Flow ◽

Flow Induced Vibration ◽

Element Analysis ◽

Internal Production

This paper presents a multiphysics approach for characterizing flow-induced vibrations (FIVs) in a subsea jumper subject to internal production flow, downstream slug, and ocean current. In the present study, the physical properties of production fluids and associated slugging behavior were characterized by pvtsim and olga programs under real subsea condition. Outcomes of the flow assurance studies were then taken as inputs of a full-scale two-way fluid–structure interaction (FSI) analysis to quantify the vibration response. To prevent onset of resonant risk, a detailed modal analysis has also be carried out to determine the modal shapes and natural frequencies. Such a multiphysics approach actually integrated the best practices currently available in flow assurance (olga and pvtsim), computational fluid dynamics (CFD), finite element analysis (FEA), and modal analysis, and hence provided a comprehensive solution to the FSI involved in a subsea jumper. The corresponding results indicate that both the internal production flow, downstream slugs, and the ocean current would induce vibration response in the subsea jumper. Compared to the vortex-induced vibration (VIV) due to the ocean current and the FIV due to the internal production flow, pressure fluctuation due to the downstream slug plays a dominant role in generating excessive vibration response and potential fatigue failure in the subsea jumper. Although the present study was mainly focused on the subsea jumper, the same approach can be applied to other subsea components, like subsea flowline, subsea riser, and other subsea production equipment.

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Influence of end Contsrains on the Global Behaviour of a Box Girder

Journal of Applied Engineering Sciences ◽

10.1515/jaes-2016-0001 ◽

2016 ◽

Vol 6 (1) ◽

pp. 7-15

Author(s):

Daniela Mihaela Boca ◽

A. Faur ◽

A. Boca

Keyword(s):

Prestressed Concrete ◽

Transport Infrastructure ◽

Box Girders ◽

3D Fem ◽

Important Data ◽

Box Girder ◽

Fem Model ◽

Global Behaviour ◽

Applied Forces ◽

Precast Prestressed Concrete

Abstract This study aims to presents the importance of end constrains, boundary conditions and position of the applied forces regarding the design of precast/prestressed concrete box girders. The study is based on a destructive test which was performed on a 37.1 m span single-cell prestressed concrete box girder. The scope of the test was to certify the usage of such girders for the new Transylvania motorway bridges. The test is numerically reproduced through a full 3D FEM model implemented in SAP2000. The influence of the end diaphragms is considered by analysing the beam’s behaviour to six loading conditions: one of which is replicating the loadings during the test, while the others are conceived as real vertical and horizontally loading scenarios. The results obtained for the girders with and without end constrains are compared. The performances of both design solutions in the presence of prestressing are highlighted where applicable. It is considered that the results of this study may provide very important data if considering that Romania has an urgent need to realize a modern and an adequate transport infrastructure.

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Study on Flow-Induced Vibration Characteristics of Hydraulic Hoist of Large-Span Upwelling Radial Steel Gate

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.117-119.241 ◽

2011 ◽

Vol 117-119 ◽

pp. 241-246

Author(s):

Zhen Hai Gao ◽

Gen Hua Yan ◽

Peng Liu ◽

Fa Zhan Chen ◽

Fei Ming Lv

Keyword(s):

Dynamic Characteristics ◽

Vibration Characteristics ◽

Vibration Response ◽

Flow Induced Vibration ◽

Structural Dynamic ◽

Large Span ◽

Response Characteristics ◽

Lever Action ◽

Structural Dynamic Characteristics ◽

Steel Gate

In this paper we conduct study on flow-induced vibration of large-span upwelling radial steel Gate and its hydraulic hoist. Place an emphasis on vibration response characteristics under two working conditions of diversion and drainage, which proves the safety of hydraulic hoist gate vibration caused by gate vibration. Firstly, we study on dynamic characteristics of fluid-structure interaction of association system of gate and start and stop lever, reveals the discipline of the effect fluid having on structural dynamic characteristics. On this basis, flow-induced vibration characteristics under two conditions of with and without start and stop lever action considered. The results indicate that the gate vibration response with hydraulic hoist used decreases, which explains start and stop lever has certain effect of restraining vibration on gate vibration. In addition, under the working condition of drainage the vibration magnitude of start and stop lever is smaller than that of gate body, which explains there is damping action during transference of gate vibration through start and stop lever. The results find out that on the assumption of optimized gate structure and hydraulic arrangement, it is practicable, safe and reliable to adopt hydraulic hoist. The achievement has directive significance on similar projects construction in the future

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27-day variations of the galactic cosmic rays intensity and anisotropy in solar minima 23/24 and 24/25 by ACE/CRIS, STEREO, SOHO/EPHIN and neutron monitors

10.5194/egusphere-egu21-13185 ◽

2021 ◽

Author(s):

Renata Modzelewska ◽

Agnieszka Gil

Keyword(s):

Cosmic Rays ◽

Large Scale ◽

Solar Rotation ◽

High Energy ◽

Galactic Cosmic Rays ◽

Magnetic Polarity ◽

Analysis Method ◽

Enhanced Diffusion ◽

Diffusion Effects ◽

Solar Wind Parameters

<p>We study the 27-day variations of galactic cosmic rays (GCRs) based on neutron monitor (NM), ACE/CRIS, STEREO and SOHO/EPHIN measurements, in solar minima 23/24 and 24/25 characterized by the opposite polarities of solar magnetic cycle. Now there is an opportunity to re-analyze the polarity dependence of the amplitudes of the recurrent GCR variations in 2007-2009 for negative A < 0 solar magnetic polarity and to compare it with the clear periodic variations related to solar rotation in 2017-2019 for positive A > 0. We use the Fourier analysis method to study the periodicity in the GCR fluxes. Since the GCR recurrence is a consequence of solar rotation, we analyze not only GCR fluxes, but also solar and heliospheric parameters examining the relationships between the 27-day GCR variations and heliospheric, as well as, solar wind parameters. We find that the polarity dependence of the amplitudes of the 27-day variations of the GCR intensity and anisotropy for NMs data is kept for the last two solar minima: 23/24 (2007-2009) and 24/25 (2017-2019) with greater amplitudes in positive A > 0 solar magnetic polarity. ACE/CRIS, SOHO/EPHIN and STEREO measurements are not governed by this principle of greater amplitudes in positive A > 0 polarity. GCR recurrence caused by the solar rotation for low energy (< 1GeV) cosmic rays is more sensitive to the enhanced diffusion effects, resulting in the same level of the 27-day amplitudes for positive and negative polarities. While high energy (> 1GeV) cosmic rays registered by NMs, are more sensitive to the large-scale drift effect leading to the 22-year Hale cycle in the 27-day GCR variation, with the larger amplitudes in the A > 0 polarity than in the A < 0.</p>

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