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An experimental and theoretical piezoelectric energy harvesting from a simply supported beam with moving mass

Mohaisen A. M., Ntayeesh T. J.

Archives of Materials Science and Engineering

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2023

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Vol. 123, nr 1

13--29

EN

Purpose: The feasibility of harvesting electrical energy from mechanical vibration is demonstrated in the thesis. In the technique, energy is harvested from simply supported beam vibration under a moving mass using a thin piezoelectric material. Design/methodology/approach: The structure is represented by a basic beam of length L that is supported at both ends and traversed by a moving mass M travelling at a constant velocity v. The Euler-Bernoulli differential equation describes its behaviour. The dynamic analysis of a beam is performed by using three moving masses of (35.61, 65.81, and 79.41) gr each travelling three uniform speeds of (1.6, 2 and 2.4) m/s. A differential equation of the electromechanical system is obtained by transforming the piezoelectric constitutive equation and solved numerically by MATLAB. Findings: The results indicate that the numerical and experimental values for the midpoint deflection of the beam and the piezoelectric voltage are very close. Research limitations/implications: Using the COMSOL programme, the proposed approach is checked by comparing results with data obtained by the finite element method (FEM). An experimental setup was also built and constructed to determine the voltage created by the piezoelectric patch and the beam response as a result of the mass travelling along the beam. Practical implications: The results show that the dynamic deflection, piezoelectric voltage, and piezoelectric energy harvesting all increase as the speed and magnitude of the moving mass increase. The harvesting power vs. load resistance curve begins at zero, increases to a maximum value, and then remains almost constant as the resistance is increased further. The optimal length of the piezoelectric patch was obtained to be 0.63 m. When the length of the beam increases, the resonant frequency decreases, and at the same time the harvested energy increases. However, increasing the beam thickness has the opposite effect; whereas raising the beam width does not affect the resonant frequency but decreases energy harvesting. Originality/value: The most essential point here is the need to have correctly built scale models. They can provide a substantial amount of information at a low cost, accommodate a variety of test settings, and aid in the selection and verification of the most effective analytical model to resolve the actual issue.

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Wpływ płyt przejściowych i wewnętrznych szyn usztywniających na odpowiedź dynamiczną wiaduktu obciążonego pociągiem szybkobieżnym

Szurgott P., Kozera D.

Modelowanie Inżynierskie

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2012

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T. 14, nr 45

127--133

PL

W pracy przedstawiono metodykę modelowania i symulacji drgań pionowych układu most – tor – pociąg szybkobieżny z wykorzystaniem oprogramowania LS-DYNA. Obiektem badań jest zespolony wiadukt kolejowy z torem podsypkowym, obciążony pociągiem szybkobieżnym ICE-3. Badania symulacyjne dla zmodernizowanego wariantu wiaduktu zostały przeprowadzone w zakresie prędkości 50-300 km/h. W wyznaczonej prędkości rezonansowej 260 km/h dokonano analizy porównawczej mostu aktualnie eksploatowanego bez płyt przejściowych i wewnętrznych szyn usztywniających, z mostem, w którym te elementy występują.

EN

A methodology of FE modeling and simulation of the bridge – track – moving train system using LS-DYNA computer code is presented. The composite (steel – concrete) viaduct equipped with the ballasted track is taken into consideration. The ICE-3 high speed train is selected as a representative for this study. The simulation for the modernized track were carried out for the velocity range between 50 to 300 km/h. A comparative analysis for the resonant speed of 260 km/h were performed for the FE models of the present viaduct and of the modernized one.

3

Wrażliwość projektowania drgań mostu żelbetowego poddanego działaniu pojazdu

Podwórna M., Śniady P.

Zeszyty Naukowe Politechniki Rzeszowskiej. Mechanika

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1999

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z. 52 [174]

71-76

EN

The sensitivity analysis of the vibrations of a single span bridge due to moving load with constant velocity is considered. The vehicle is modelled as a linear discrete (four degrees of freedom) mass-spring-damper system. The effect of the quantity b (bottom width of the bridge beam) on the beam's deflection is showed.