Experimental vibration response of homogeneous beam models damaged by notches and strengthened by CFRP lamina

2018 ◽  
Vol 206 ◽  
pp. 563-577 ◽  
Author(s):  
R. Capozucca ◽  
E. Magagnini
Keyword(s):  
Vibration Response ◽  
Homogeneous Beam

Vibration Response Imaging (VRI) bei Quarzstaubbedingten Lungenveränderungen

Pneumologie ◽  
2007 ◽  
Vol 61 (S 1) ◽  
Author(s):  
F Hoffmeyer ◽  
V Harth ◽  
J Bünger ◽  
J Henry ◽  
A Dehlinger ◽  
...  
Keyword(s):  
Vibration Response ◽  
Vibration Response Imaging

Vibration Response Imaging (VRI) bei der Anwendung in einer internistischen Allgemeinpraxis – eine Machbarkeitsstudie

Pneumologie ◽  
2008 ◽  
Vol 62 (S 2) ◽  
Author(s):  
HD Becker ◽  
M Gat ◽  
S Thiemann
Keyword(s):  
Vibration Response ◽  
Vibration Response Imaging

Modal characteristics and fluid–structure interaction vibration response of submerged impeller

2021 ◽  
pp. 107754632110036
Author(s):  
Shihui Huo ◽  
Hong Huang ◽  
Daoqiong Huang ◽  
Zhanyi Liu ◽  
Hui Chen
Keyword(s):  
Flow Field ◽  
Unsteady Flow ◽  
Damping Ratio ◽  
Pure Water ◽  
Vibration Response ◽  
Modal Identification ◽  
Liquid Oxygen ◽  
Modal Characteristics ◽  
Oxygen Pump ◽  
Turbo Pump

Turbo pump is one of the elements with the most complex flow of liquid rocket engine, and as an important component of turbo pump, an impeller is the weak point affecting its reliability. In this study, a noncontact modal characteristic identification technique was proposed for the liquid oxygen pump impeller. Modal characteristics of the impeller under three different submerged media, air, pure water, and brine with same density as liquid oxygen, were tested based on the noncontact modal identification technology. Submersion state directly affects the modal frequencies and damping ratio. The transient vibration response characteristics of the impeller excited by the unsteady flow field was achieved combining with unsteady flow field analysis and transient dynamic analysis in the whole flow passage of the liquid oxygen pump. Vibration responses at different positions of the impeller show 10X and 20X frequencies, and the amplitude at the root of short blade is significant, which needs to be paid more attention in structural design and fatigue evaluation.

scholarly journals Vibration control for a beam structure using an electromagnetic damper with velocity feedback. 1st report Forced vibration response.

1985 ◽  
Vol 51 (472) ◽  
pp. 3235-3241
Author(s):  
Hiroyuki KOJIMA ◽  
Humihiko NIIYAMA ◽  
Kosuke NAGAYA ◽  
Katsumi NAGAI
Keyword(s):  
Vibration Control ◽  
Forced Vibration ◽  
Vibration Response ◽  
Beam Structure ◽  
Velocity Feedback ◽  
Electromagnetic Damper

Railway crossing vertical vibration response prediction using a data-driven neuro-fuzzy model – Influence of train factors

2021 ◽  
pp. 095440972098666
Author(s):  
Kaveh Mehrzad ◽  
Shervan Ataei
Keyword(s):  
Model Comparison ◽  
Selection Process ◽  
Fuzzy Model ◽  
Response Prediction ◽  
Vibration Response ◽  
Vibration Monitoring ◽  
Data Driven ◽  
Steady Increase ◽  
Neuro Fuzzy ◽  
Railway Crossing

This paper provides a data-driven model of the vibration response of a railway crossing during vehicle passages. Many of the features of trains passing through instrumented crossing are extracted from measured data. Based on the feature selection process, speed, dynamic axle load and the number of wagons are found proper inputs in the prediction model. Train-crossing interaction response at a crossing due to passing trains is modeled from a data-driven Neuro-Fuzzy soft computing approach. Locally Linear Model Tree (LOLIMOT) is applied to predict the crossing nose acceleration. The model comparison against measurements shows that the ability to predict the extrapolation cases at off-range speeds has satisfactory compatibility. The monitored passing trains are ranked based on the LOLIMOT input space dimension cuts and extrapolation of the model up to higher train speeds. The influence of train factors (i.e. speed, dynamic axle load, number of wagons) on crossing response is demonstrated. Also, based on the analysis results, it is concluded that with a steady increase in train speeds, some trains show a greater amplification in vibration response than others. The results can be applied in data processing in the crossing vibration monitoring and detection of trains with crossing impact sensitive to speed increasing that can lead to proper operation policies to reduce damages and maintenance costs.

Dynamic modeling and vibration response analysis of a synchronous motorized spindle with inclined eccentricity

2021 ◽  
pp. 107754632110233
Author(s):  
Wei Feng ◽  
Kun Zhang ◽  
Baoguo Liu ◽  
Weifang Sun ◽  
Sijie Cai
Keyword(s):  
Analytical Method ◽  
Vibration Response ◽  
Mass Force ◽  
Motorized Spindle ◽  
Dynamic Displacement ◽  
Unbalanced Mass ◽  
Unbalanced Magnetic Pull ◽  
Spindle Bearing ◽  
Mass Eccentricity ◽  
Bearing System

The air-gap eccentricity will produce unbalanced magnetic pull and cause vibrations and noises in a motor. In this study, the dynamic behavior of a synchronous motorized spindle with inclined eccentricity is investigated. A semi-analytical method is proposed to model the unbalanced magnetic pull and the electromagnetic torque of a rotor with inclined eccentricity, and the semi-analytical method is verified by the finite element method. The dynamic model of a spindle-bearing system is built by taking the centrifugal force and gyroscopic effects into account. Then, the vibration response of dynamic displacement eccentricity, inclined eccentricity including displacement eccentricity and angle eccentricity, rotating speed, and unbalanced mass eccentricity in both time domain and frequency domain are simulated and analyzed. The results show that the eccentricities can lead to fluctuations in amplitudes of the dynamic displacement response and the angle response. The frequency components of the dynamic responses are the combination of rotating frequency, VC frequency, and power frequency. It is indicated that the coupling interactions of bearing forces, unbalanced mass force, and unbalanced magnetic pull have an obvious effect on the spindle-bearing system.

Sign in / Sign up

Export Citation Format

Share Document