Dynamic characteristics of inertial actuator featuring piezoelectric materials: Experimental verification

A new concept for the evaluation of flowmeter dynamic response is presented. A technique based on hydraulic line dynamics is applied to achieve accurate measurements of the reference flowrate. The major components in the equipment used in experimental verification of the theory were a test pipe, a pulsating flow generator, three pressure transducers, an A/D converter, and a microcomputer system. This equipment allowed the dynamic characteristics of a flowmeter to be investigated in both the time and frequency domains. Comparisons of flowrates measured using the line dynamic technique and the same flowrates recorded by the flowmeter are presented. The results confirm the feasibility and practicability of the dynamic line technique for measuring rapidly varying flows.

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Finite Element Analysis of Piezoelectric Pile Dynamic Characteristics

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.881-883.1126 ◽

2014 ◽

Vol 881-883 ◽

pp. 1126-1129

Author(s):

Ai Guo Zhang ◽

Tie Jun Yang ◽

Jing Tao Du ◽

Peng Lv ◽

Xin Guang Li

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Layer Thickness ◽

Dynamic Characteristics ◽

Piezoelectric Materials ◽

Element Analysis

The dynamic characteristics of the piezoelectric materials are demonstrated by the ANSYS finite element techniques. Based on the analyses of the modeling results of the monolayer piezoelectric materials, the dynamic characteristics of the multi-layer piezoelectric pile are further investigated. For piezoelectric materials with a certain thickness, it is found that the resulting stroke and output increases with the decrease of the layer thickness which is attributed by the increased layers and substantially unchanged overall-stiffness.

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Crack Detection in Offshore Structures Using Dynamic Characteristics and Wavelet Transform

Volume 2: Structures, Safety and Reliability ◽

10.1115/omae2009-79647 ◽

2009 ◽

Author(s):

Zhao-de Zhang ◽

Yong-he Xie ◽

De-yu Wang

Keyword(s):

Wavelet Transform ◽

Frequency Response ◽

Dynamic Characteristics ◽

Experimental Verification ◽

Strain Energy ◽

Crack Detection ◽

Offshore Structures ◽

Dynamic Parameters ◽

Response Functions ◽

Modal Strain Energy

Dynamic parameters of offshore structures, such as frequencies, modal shapes, modal strain energy (MSE) and frequency response functions (FRF) are numerically and experimentally studied to detect the crack in the structures. A 3-pile and a 4-pile platform are analyzed. And a model of the 3-pile platform has been constructed for the experimental verification. When a crack occurs, the parameters of the structure will change. The shift of these parameters may be applied to identify the crack, the location and even the crack magnitude. Wavelet transform can be employed to find the singularity of the signal, so as to predict the early crack. The dynamic parameters due to mass change are also evaluated.

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