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Response Variation of Chladni Patterns on Vibrating Elastic Plate Under Electro-Mechanical Oscillation
Nigerian Journal of Technology (NIJOTECH) Vol. 38, No. 3, July 2019, pp. 540 – 548 Copyright© Faculty of Engineering, University of Nigeria, Nsukka, Print ISSN: 0331-8443, Electronic ISSN: 2467-8821 www.nijotech.com http://dx.doi.org/10.4314/njt.v38i3.1 RESPONSE VARIATION OF CHLADNI PATTERNS ON VIBRATING ELASTIC PLATE UNDER ELECTRO-MECHANICAL OSCILLATION A. E. Ikpe1,*, A. E. Ndon2 and E. M. Etuk3 1, DEPT OF MECHANICAL ENGINEERING, UNIVERSITY OF BENIN, P.M.B. 1154, BENIN, EDO STATE, NIGERIA 2, DEPT OF CIVIL ENGINEERING, AKWA IBOM STATE UNIVERSITY, MKPAT ENIN, AKWA IBOM STATE, NIGERIA 3, DEPT OF PRODUCTION ENGINEERING, UNIVERSITY OF BENIN, P.M.B. 1154, BENIN, EDO STATE, NIGERIA E-mail addresses: 1 [email protected], 2 [email protected], 3 [email protected] ABSTRACT Fine grain particles such as sugar, sand, salt etc. form Chladni patterns on the surface of a thin plate subjected to acoustic excitation. This principle has found its relevance in many scientific and engineering applications where the displacement or response of components under the influence of vibration is vital. This study presents an alternative method of determining the modal shapes on vibrating plate in addition to other existing methods like the experimental method by Ernst Chladni. Three (3) finite element solvers namely: CATIA 2017 version, ANSYS R15.0 2017 version and HYPERMESH 2016 version were employed in the modelling process of the 0.40 mm x 0.40 mm plate and simulation of corresponding mode shapes (Chladni patterns) as well as the modal frequencies using Finite Element Method (FEM). Result of modal frequency obtained from the experimental analysis agreed with the FEM simulated, with HYPERMESH generated results being the closest to the experimental values. -
Orbital Shaped Standing Waves Using Chladni Plates
doi.org/10.26434/chemrxiv.10255838.v1 Orbital Shaped Standing Waves Using Chladni Plates Eric Janusson, Johanne Penafiel, Andrew Macdonald, Shaun MacLean, Irina Paci, J Scott McIndoe Submitted date: 05/11/2019 • Posted date: 13/11/2019 Licence: CC BY-NC-ND 4.0 Citation information: Janusson, Eric; Penafiel, Johanne; Macdonald, Andrew; MacLean, Shaun; Paci, Irina; McIndoe, J Scott (2019): Orbital Shaped Standing Waves Using Chladni Plates. ChemRxiv. Preprint. https://doi.org/10.26434/chemrxiv.10255838.v1 Chemistry students are often introduced to the concept of atomic orbitals with a representation of a one-dimensional standing wave. The classic example is the harmonic frequencies which produce standing waves on a guitar string; a concept which is easily replicated in class with a length of rope. From here, students are typically exposed to a more realistic three-dimensional model, which can often be difficult to visualize. Extrapolation from a two-dimensional model, such as the vibrational modes of a drumhead, can be used to convey the standing wave concept to students more easily. We have opted to use Chladni plates which may be tuned to give a two-dimensional standing wave which serves as a cross-sectional representation of atomic orbitals. The demonstration, intended for first year chemistry students, facilitates the examination of nodal and anti-nodal regions of a Chladni figure which students can then connect to the concept of quantum mechanical parameters and their relationship to atomic orbital shape. File list (4) Chladni manuscript_20191030.docx (3.47 MiB) view on ChemRxiv download file SUPPORTING INFORMATION Materials and Setup Phot.. -
Martinho, Claudia. 2019. Aural Architecture Practice: Creative Approaches for an Ecology of Affect
Martinho, Claudia. 2019. Aural Architecture Practice: Creative Approaches for an Ecology of Affect. Doctoral thesis, Goldsmiths, University of London [Thesis] https://research.gold.ac.uk/id/eprint/26374/ The version presented here may differ from the published, performed or presented work. Please go to the persistent GRO record above for more information. If you believe that any material held in the repository infringes copyright law, please contact the Repository Team at Goldsmiths, University of London via the following email address: [email protected]. The item will be removed from the repository while any claim is being investigated. For more information, please contact the GRO team: [email protected] !1 Aural Architecture Practice Creative Approaches for an Ecology of Affect Cláudia Martinho Goldsmiths, University of London PhD Music (Sonic Arts) 2018 !2 The work presented in this thesis has been carried out by myself, except as otherwise specified. December 15, 2017 !3 Acknowledgments Thanks to: my family, Mazatzin and Sitlali, for their support and understanding; my PhD thesis’ supervisors, Professor John Levack Drever and Dr. Iris Garrelfs, for their valuable input; and everyone who has inspired me and that took part in the co-creation of this thesis practical case studies. This research has been supported by the Foundation for Science and Technology fellowship. Funding has also been granted from the Department of Music and from the Graduate School at Goldsmiths University of London, the arts organisations Guimarães Capital of Culture 2012, Invisible Places and Lisboa Soa, to support the creation of the artworks presented in this research as practical case studies. -
Wave Goodbye to Sound Waves
www.cymascope.com Wave Goodbye to Sound Waves Wave Goodbye to Sound Waves John Stuart Reid Sound is a wave, right? If you share this commonly held belief it is probably because everything you have ever read or been told about sound, whether from high school, popular science books or university courses has said so. And yet, if our eyes could see sound, we would not see waves wiggling their way through the air. Instead, we would see something quite surprising, as you will soon learn. So how did the popular belief in ‘sound waves’ begin? The confusion may have begun with German musician and physicist Ernst Chladni (1756-1827), sometimes described as ‘the father of acoustics.’ Chladni was inspired by the earlier work of English scientist Robert Hooke (1635–1703), who made contributions to many fields including mathematics, optics, mechanics, architecture and astronomy. In 1680 Hooke devised an apparatus consisting of a glass plate covered with flour that he ‘played’ with a violin bow. He was fascinated by the resulting patterns. Around 1800 this phenomenon Ernst Chladni was further explored by Ernst Robert Hooke Chladni, who used a brass plate and sand. Brass is a highly resonant metal and the bell-like sounds he created resulted in the sand grains organizing themselves into complex geometric patterns. These archetypal patterns are now referred to as ‘Chladni Figures,’ although the originator of the invention was actually Hooke. Chladni demonstrated this seemingly magical phenomenon all over Europe and he even had an audience with Napoleon. The French leader was so impressed that he sponsored a competition with The French Academy of Sciences in order to acquire an explanation as to the mechanism behind the sand patterns. -
CHLADNI PATTERNS by Tom and Joseph Irvine
CHLADNI PATTERNS By Tom and Joseph Irvine September 18, 2000 Email: [email protected] ______________________________________________________________________ HISTORICAL BACKGROUND Ernst Chladni (1756-1827) was a German physicist who performed experimental studies of vibrating plates. Specifically, he spread fine sand over metal or glass plates. He then excited the fundamental natural frequency of the plate by stroking a violin bow across one of its edges. As a result, a standing wave formed in the plate. A standing wave has "anti-nodes" where the maximum displacement occurs. A standing wave also has "nodes" where no displacement occurs. For a vibrating plate, the nodes occur along "nodal lines." In Chladni's experiment, the sand grains responded to the excitation by migrating to the nodal lines of the plates. The grains thus traced the nodal line pattern. Sophie Germain (1776-1831) derived mathematical equations to describe Chladni's experiments. She published these equations in Memoir on the Vibrations of Elastic Plates. Jules Lissajous (1822-1880) performed further vibration research using Chladni's test methods. THEORY Elastic plates have numerous natural frequencies. The lowest natural frequency is called the fundamental natural frequency. The fundamental frequency is usually the dominant frequency. Each natural frequency has a corresponding "mode." The mode is defined in terms of its nodal line pattern. Each mode has a unique pattern. Points on opposite sides of a nodal line vibrate "180 degrees out-of-phase." Stroking a plate with a violin bow may excite several natural frequencies, thus complicating the experiment. Again, the response will usually be dominated by the fundamental mode. 1 The higher modes can be individually excited, to some extent, by stroking the plate at different edge locations. -
Orbital Shaped Standing Waves Using Chladni Platess
88 Chem. Educator 2020, 25, 88–91 Orbital Shaped Standing Waves Using Chladni Platess Eric Janusson, Johanne Penafiel, Shaun MacLean, Andrew Macdonald, Irina Paci* and J. Scott McIndoe* Department of Chemistry, University of Victoria, P.O. Box 3065 Victoria, BC V8W3V6, Canada, [email protected], [email protected] Received December 3, 2019. Accepted February 5, 2020. Abstract: Chemistry students are often introduced to the concept of atomic orbitals with a representation of a one-dimensional standing wave. The classic example is the harmonic frequencies, which produce standing waves on a guitar string; a concept that is easily replicated in class with a length of rope. From here, students are typically exposed to a more realistic three-dimensional model, which can often be difficult to visualize. Extrapolation from a two-dimensional model, such as the vibrational modes of a drumhead, can be used to convey the standing wave concept to students more easily. We have opted to use Chladni plates, which may be tuned to give a two-dimensional standing wave that serves as a cross-sectional representation of atomic orbitals. The demonstration, intended for first year chemistry students, facilitates the examination of nodal and anti-nodal regions of a Chladni figure that students can connect to the concept of quantum mechanical parameters and their relationship to atomic orbital shape. Introduction orbitals. There exist excellent examples in the literature of two- and three-dimensional visualizations of atomic orbitals, Understanding that an electron in an orbital can be thought making use of custom or proprietary software in order to of as a three-dimensional standing wave is a tough concept to produce plots of atomic and molecular orbitals and wrap one’s head around. -
Sine Waves and Simple Acoustic Phenomena in Experimental Music - with Special Reference to the Work of La Monte Young and Alvin Lucier
Sine Waves and Simple Acoustic Phenomena in Experimental Music - with Special Reference to the Work of La Monte Young and Alvin Lucier Peter John Blamey Doctor of Philosophy University of Western Sydney 2008 Acknowledgements I would like to thank my principal supervisor Dr Chris Fleming for his generosity, guidance, good humour and invaluable assistance in researching and writing this thesis (and also for his willingness to participate in productive digressions on just about any subject). I would also like to thank the other members of my supervisory panel - Dr Caleb Kelly and Professor Julian Knowles - for all of their encouragement and advice. Statement of Authentication The work presented in this thesis is, to the best of my knowledge and belief, original except as acknowledged in the text. I hereby declare that I have not submitted this material, either in full or in part, for a degree at this or any other institution. .......................................................... (Signature) Table of Contents Abstract..................................................................................................................iii Introduction: Simple sounds, simple shapes, complex notions.............................1 Signs of sines....................................................................................................................4 Acoustics, aesthetics, and transduction........................................................................6 The acoustic and the auditory......................................................................................10 -
Analysis of Vibrational Modes of Chemically Modified Tone Wood
University of Northern Iowa UNI ScholarWorks Honors Program Theses Honors Program 2018 Analysis of vibrational modes of chemically modified onet wood Madison Flesch University of Northern Iowa Let us know how access to this document benefits ouy Copyright ©2018 Madison Flesch Follow this and additional works at: https://scholarworks.uni.edu/hpt Part of the Biology and Biomimetic Materials Commons, Chemistry Commons, and the Other Music Commons Recommended Citation Flesch, Madison, "Analysis of vibrational modes of chemically modified onet wood" (2018). Honors Program Theses. 315. https://scholarworks.uni.edu/hpt/315 This Open Access Honors Program Thesis is brought to you for free and open access by the Honors Program at UNI ScholarWorks. It has been accepted for inclusion in Honors Program Theses by an authorized administrator of UNI ScholarWorks. For more information, please contact [email protected]. ANALYSIS OF VIBRATIONAL MODES OF CHEMICALLY MODIFIED TONE WOOD A Thesis Submitted In Partial Fulfillment Of the Requirements for the Designation University Honors Madison Flesch University of Northern Iowa May 2018 This Study by: Madison Flesch Entitled: Analysis of Vibrational Modes of Chemically Modified Tone Wood Has been approved as meeting the thesis or project requirement for the Designation University Honors __________ _______________________________________________________________ Date Dr. Curtiss Hanson, Honors Thesis Advisor __________ _______________________________________________________________ Date Dr. Jessica Moon, Director, University Honors Program Acknowledgements I would like to thank Dr. Curtiss Hanson profusely for all of his guidance, contributions, and time for the duration of this project. I would also like to acknowledge Dr. Joshua Sebree for his time and contribution to this project in the form of graphing many of the data collections taken during this time. -
Manipulating Chladni Patterns of Ferromagnetic Materials by an External Magnetic Field
Tech Science Press DOI: 10.32604/sv.2021.015008 ARTICLE Manipulating Chladni Patterns of Ferromagnetic Materials by an External Magnetic Field Kenneth R. Podolak*, Vihan A.W. Wickramasinghe, Gareth A. Mansfield and Alex M. Tuller State University of New York, Plattsburgh, 12901, USA *Corresponding Author: Kenneth R. Podolak. Email: [email protected] Received: 15 November 2020 Accepted: 23 March 2021 ABSTRACT Ernst Chladni is called the father of acoustics for his work, which includes investigating patterns formed by vibrating plates. Understanding these patterns helps research involving standing waves and other harmonic beha- viors, including studies of single electron orbits in atoms. Our experiment vibrates circular plates which result in well-known patterns. Alternatively to traditional experiments that used sand or salt, we use magnetic materials, namely iron filings and nickel powder. We then manipulate the patterns by applying a localized external magnetic field to one of the rings that moves a segment of the magnetic material in that ring to the next inner ring. The results show a significant decrease in magnetic field necessary to move the magnetic material at higher frequencies as well as a significant decrease in the magnetic field required to move the magnetic material as nickel powder is substituted for iron filings while keeping the mass constant. KEYWORDS Chladni; ferromagnetism; acoustics 1 Introduction Insights into the quantum world can be experimentally studied by driving oscillations and experimentally measuring the effects on resonant states [1,2]. An early study of these oscillations comes from a German physicist, Chladni, who discovered that a vibrating metal plate would take randomly distributed sand particles at a particular set resonant frequency and vibrate them away from the antinodes and concentrate the sand at the nodes [3]. -
A Study to Explore the Effects of Sound Vibrations on Consciousness
International Journal of Social Work and Human Services Practice Horizon Research Publishing Vol.6. No.3 July, 2018, pp. 75-88 A Study to Explore the Effects of Sound Vibrations on Consciousness Meera Raghu Independent Researcher, New Zealand Abstract Sound is a form of energy produced by cause happiness, joy, courage or calmness, dissonant vibrations caused by movement of particles. Sound can intervals can cause tension, anger, fear or sadness, thereby travel through solids (such as metal, wood, membranes), affecting the emotional aspect of consciousness. liquids (water) and gases (air). The sound vibrations that reach our ear are produced by the movement of particles in Keywords Consciousness, Sound, Vibration, Music, the air surrounding the source of sound. The movement or Emotion, Chladni, Pattern, Energy vibration of particles produces waves of sound. Sound waves are longitudinal and travel in the direction of propagation of vibrations. The pitch of sound is related directly to its frequency, which is given by the number of Introduction vibrations or cycles per second. The higher the pitch of sound, the higher is its frequency, and the lower the pitch, Sound is everywhere. There is perpetual movement and the lower is its frequency. Human ear can hear sounds of action in the world around us, and this produces a variety of frequencies ranging from 20 – 20,000 cycles per second (or sounds, such as those coming from Nature, from animals, Hertz – Hz). Sound waves can be visually seen and studied those generated by humans in the form of speech or music, using ‘Chladni’ plates, which was devised and those that are generated by vehicles, machines, gadgets that experimented by Ernst Chladni, a famous physicist with a are used for comfort, leisure and convenience. -
Ernst Florens Friedrich Chladni (1756 – 1827) Chladni Vibration Modes of Guitar Plate
Ernst Florens Friedrich Chladni (1756 – 1827) Chladni vibration modes of guitar plate From Wikipedia, the free encyclopedia, http://en.wikipedia.org/wiki/Ernst_Chladni ! Ernst Florens Friedrich Chladni was a German physicist and musician. His important works include research on vibrating plates and the calculation of the speed of sound for different gases. For this some call him the "Father of Acoustics". He also did pioneering work in the study of meteorites, and therefore is regarded by some as the "Father of Meteoritics" as well. Personal life: Although Chladni was born in Wittenberg, Germany, Chladni's family was from Kremnica, a mining town now in central Slovakia, then part of the Kingdom of Hungary. This has led to Chladni as being identified in the literature as German, Hungarian and Slovak.Martin Chladni, Ernst Chladni's grandfather Chladni came from an educated family of academics and learned men. Chladni's great-grandfather, Georg Chladni (1637–92), a Lutheran clergyman, had to flee Kremnica on October 19, 1673 during the Counter Reformation. Chladni's grandfather, Martin Chladni (1669–1725), was also a Lutheran theologian, and in 1710 became professor of theology at the University of Wittenberg, and from 1720-1721 was dean of the faculty of theology and later rector of the university. Chaldni's uncle, Justus Georg Chladni (1701–1765), was a law professor at University of Wittenberg. Another uncle, Johann Martin Chladni (1710–1759), was a theologian and historian, and professor at the University of Erlangen and the University of Leipzig. Chladni's father, Ernst Martin Chladni (1715–1782), was a law professor and rector of the University of Wittenberg, where he joined the law faculty in 1746.[citation needed] Chaldni's father disapproved of his son's interest in science and insisted that Chladni become a lawyer. -
1 Survey-Dada
A&EMSURVEY.qxd 1/10/08 17:51 Page 4 Phaidon Press Limited Regent's Wharf All Saints Street London N1 9PA Phaidon Press Inc. ART AND ELECTRONIC 180 Varick Street New York, NY 10014 www.phaidon.com First published 2009 © 2009 Phaidon Press Limited All works © the artists or the estates of MEDIA the artists unless otherwise stated. ISBN: 0 7148 4782 8 A CIP catalogue record of this book is available from the British Library. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without the written permission of Phaidon Press. Designed by Hoop Design Printed in Hong Kong cover, Ben Rubin and Mark Hansen Listening Post 2001–03 inside flap, James Turrell Catso, Red, 1967, 1994 pages 2–3 Robert Rauschenberg with Billy Klüver Soundings 1968 page 4 Charlotte Moorman and Nam June Paik TV Bra 1975 back cover and spine, interior page, Tanaka Atsuko Electric Dress 1957 EDITED BY EDWARD A. SHANKEN A&EMSURVEY.qxd 1/10/08 17:51 Page 6 CHARGED ENVIRONMENTS page 96 PREFACE EDWARD A. DOCUMENTS page 190 WORKS page 54 LE CORBUSIER, Iannis XENAKIS, Edgard VARÈSE Philips Pavilion, 1958 page 97 Carolee SCHNEEMANN with E.A.T. Snows, 1967 page 98 John CAGE Imaginary Landscape No. 4 (1951), 1951 page 99 SHANKEN page 10 MOTION, DURATION, ILLUMINATION MOTION, DURATION, ILLUMINATION PULSA Boston Public Gardens Demonstration, 1968 page 100 Frank GILLETTE and Ira SCHNEIDER Wipe Cycle, 1968 page 100 page 55 Robert RAUSCHENBERG with Billy KLÜVER Soundings, 1968 page 100 László MOHOLY-NAGY Light-Space Modulator, 1923–30 page 55 page 193 Wolf VOSTELL and Peter SAAGE Electronic Dé-Coll/age Happening Room (Homage à Dürer), 1968 page 101 Naum GABO Kinetic Construction (Standing Wave), 1919–20 page 56 Ted VICTORIA Solar Audio Window Transmission, 1969–70 page 102 Thomas WILFRED Opus 161, 1965–6 page 57 Wen-Ying TSAI with Frank T.