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dc.contributor.authorKadam, Rahul Sadashiven_US
dc.date.accessioned2014-03-14T20:42:47Z
dc.date.available2014-03-14T20:42:47Z
dc.date.issued2006-07-20en_US
dc.identifier.otheretd-08052006-111525en_US
dc.identifier.urihttp://hdl.handle.net/10919/34359
dc.description.abstractHand transmitted vibration (HTV) is one of the most common hazards faced by workers in the construction industry. A major source of HTV is hand held percussion tools, such as pneumatically driven chipping hammers and rock drills. This thesis presents a new approach to measuring the vibration from these tools using an experimental hand arm model to which the tools are attached. The experimental hand-arm model has been designed to have similar dynamic characteristics to that of a human hand-arm system. This approach addresses the issue of repeatability as HTV measurements suffer from variability between cases. The measured acceleration of the hand-arm system is in range or close to range of the measured accelerations of the test subjects with superior repeatability. Further, the thesis presents a nonlinear numerical model of a pneumatic impact hammer. Fundamentally, the numerical model was made up of two different sub-models, 1) a fluid flow model and 2) a structural dynamic model. The fluid flow model was based on the equations for mass flow rate of air though a bleed orifice assuming an isentropic process. The second sub-model deals with modeling the structural components of the impact hammer consisting of the major hammer like the center body, handle, piston and chisel as well as the human hand and the ground. Time domain simulations of the hammer were carried out by using a state space formulation to get displacements, velocities and accelerations of the each component as well as the exhaust jet velocities. Experiments were carried out to measure the handle response and exhaust jet velocities as well as pressure profiles. The results obtained from the numerical model were then validated using these experimental results. Finally, a parametric study using the numerical model was carried out to explore different vibration control techniques.en_US
dc.publisherVirginia Techen_US
dc.relation.haspartthesis_rkadam_2006.pdfen_US
dc.rightsI hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to Virginia Tech or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.en_US
dc.subjectHand Transmitted Vibrationsen_US
dc.subjectState-space Modelingen_US
dc.subjectVibration and Acoustic Characterizationen_US
dc.subjectNumerical Modelingen_US
dc.subjectPneumatic Impact Hammeren_US
dc.titleVibration Characterization and Numerical Modeling of a Pneumatic Impact Hammeren_US
dc.typeThesisen_US
dc.contributor.departmentMechanical Engineeringen_US
dc.description.degreeMaster of Scienceen_US
thesis.degree.nameMaster of Scienceen_US
thesis.degree.levelmastersen_US
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen_US
thesis.degree.disciplineMechanical Engineeringen_US
dc.contributor.committeechairJohnson, Martin E.en_US
dc.contributor.committeememberInman, Daniel J.en_US
dc.contributor.committeememberBurdisso, Ricardo A.en_US
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-08052006-111525/en_US
dc.date.sdate2006-08-05en_US
dc.date.rdate2006-10-16
dc.date.adate2006-10-16en_US


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