Theoretical Development and Experimental Validation of Local Volume Displacement Sensors for a Vibrating Beam

2000 ◽  
Vol 123 (1) ◽  
pp. 110-118 ◽  
Author(s):  
Marcellin B. Zahui ◽  
James W. Kamman ◽  
Koorosh Naghshineh
Keyword(s):  
Boundary Conditions ◽  
Experimental Validation ◽  
Theoretical Development ◽  
Local Volume ◽  
Control Techniques ◽  
General Methodology ◽  
Displacement Sensors ◽  
Vibrating Beams ◽  
Further Development ◽  
Linear Shape

Further development of local volume displacement sensors is presented. This development supports the implementation of noise control techniques that are based on minimization of local volume displacements, velocities, or accelerations of a vibrating structure. In this paper, we present a general methodology for the development of local volume displacement sensors for vibrating beams using P_olyV_inyliD_ene F_luoride (PVDF). This methodology was verified experimentally for a clamped beam. The local volume displacement measured using a single PVDF sensor matched the local volume displacement found using multiple accelerometer measurements. The resulting sensors span the entire length of the beam. They have a quadratic shape over that portion of the beam whose volume displacement is desired, and they have a linear shape over all other sections. Sensor design issues for different beam boundary conditions are discussed along with a presentation of some sample sensor shapes for various beam segments and boundary conditions.

Optimising the Efficiency of Storm Water Settling Basins by Means of Bypassing

1993 ◽  
Vol 27 (5-6) ◽  
pp. 105-110 ◽  
Author(s):  
F. H. L. R. Clemens ◽  
H. J. van Mameren ◽  
J. Kollen
Keyword(s):  
Boundary Conditions ◽  
Dynamic Behaviour ◽  
Storm Water ◽  
Mixed System ◽  
Research Needs ◽  
Settling Basin ◽  
Potential Increase ◽  
Overall Efficiency ◽  
Further Development

The reduction in pollutional load realised by storm water settling basins is potentially reduced due to the occurrence of a partially mixed situation in the basin or due to resuspension of settled material. The decrease in efficiency can theoretically be avoided by means of partially bypassing the basin. In order to quantify the potential increase in efficiency a settling basin in Amersfoort is taken as an example. This basin seems to behave like an almost completely mixed system, bypassing would increase the overall efficiency from ca. 34 % to ca 39 % for three overflows. The dynamic behaviour of settling basins, scouring conditions and the boundary conditions for which settling basins are to be designed are the research needs for further development in the field of storm water settling basins.

scholarly journals Mode Shape-Based Damage Detection Method (MSDI): Experimental Validation

2021 ◽  
Vol 11 (10) ◽  
pp. 4589
Author(s):  
Ivan Duvnjak ◽  
Domagoj Damjanović ◽  
Marko Bartolac ◽  
Ana Skender
Keyword(s):  
Boundary Conditions ◽  
Damage Detection ◽  
Mode Shape ◽  
Experimental Validation ◽  
Detection Method ◽  
Dynamic Properties ◽  
Damage Index ◽  
Main Principle ◽  
The Difference ◽  
Different Levels

The main principle of vibration-based damage detection in structures is to interpret the changes in dynamic properties of the structure as indicators of damage. In this study, the mode shape damage index (MSDI) method was used to identify discrete damages in plate-like structures. This damage index is based on the difference between modified modal displacements in the undamaged and damaged state of the structure. In order to assess the advantages and limitations of the proposed algorithm, we performed experimental modal analysis on a reinforced concrete (RC) plate under 10 different damage cases. The MSDI values were calculated through considering single and/or multiple damage locations, different levels of damage, and boundary conditions. The experimental results confirmed that the MSDI method can be used to detect the existence of damage, identify single and/or multiple damage locations, and estimate damage severity in the case of single discrete damage.

Growth regime map for liquid-bound granules: further development and experimental validation

2001 ◽  
Vol 117 (1-2) ◽  
pp. 83-97 ◽  
Author(s):  
Simon M. Iveson ◽  
Philippe A.L. Wauters ◽  
Sarah Forrest ◽  
James D. Litster ◽  
Gabrie M.H. Meesters ◽  
...  
Keyword(s):  
Experimental Validation ◽  
Growth Regime ◽  
Regime Map ◽  
Further Development

Vibration of a Simply Supported L-Shaped Plate

1997 ◽  
Vol 119 (3) ◽  
pp. 464-467 ◽  
Author(s):  
R. Solecki
Keyword(s):  
Boundary Conditions ◽  
Integral Equations ◽  
Natural Vibration ◽  
Boundary Integral Equations ◽  
Rectangular Domain ◽  
Boundary Integral ◽  
Theoretical Development ◽  
Natural Vibrations ◽  
Simply Supported ◽  
Discontinuous Functions

Recently Solecki (1996) has shown that a differential equation for vibration of a rectangular plate with a cutout can be reduced to boundary integral equations. This was accomplished by filling the cutout with a “patch” made of the same material as the rest of the plate and separated from it by an infinitesimal gap. Thanks to this procedure it was possible to apply finite Fourier transformation of discontinuous functions in a rectangular domain. Subsequent application of the available boundary conditions led to a system of boundary integral equations. A plate simply supported along the perimeter, and fixed along the cutout (an L-shaped plate), was analyzed as an example. The general solution obtained by Solecki (1996) serves here to determine the frequencies of natural vibration of a L-shaped plate simply supported all around its perimeter. This problem is, however, more complicated than the previous example: to satisfy the boundary conditions an infinite series depending on discontinuous functions must be differentiated. The theoretical development is illustrated by numerical values of the frequencies of the natural vibrations of a square plate with a square cutout. The results are compared with the results obtained using finite elements method.

scholarly journals Chladni Figures Simulation on a Rectangular Plate

2021 ◽  
Vol 26 (3) ◽  
Author(s):  
Pavlo Ihorovych Krysenko ◽  
Maksym Olehovych Zoziuk ◽  
Oleksandr Ivanovych Yurikov ◽  
Dmytro Volodymyrovych Koroliuk ◽  
Yurii Ivanovych Yakymenko
Keyword(s):  
Fourier Transform ◽  
Boundary Conditions ◽  
Rectangular Plate ◽  
Standing Waves ◽  
Physical Nature ◽  
Practical Significance ◽  
The Fourier Transform ◽  
Further Development ◽  
Top View ◽  
Chladni Figures

An analytical model for creating flat Chladni figures is presented. The equation of a standing wave in the simplest boundary conditions and the Fourier transform are used. Top view images are shown at different frequencies. The practical significance of the results obtained for the further development of the field of creating Chladni figures based on standing waves of different physical nature has been determined.

Sign in / Sign up

Export Citation Format

Share Document