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James W. Axley. Revi, Frank Massachusetts Institute of Technology. Dept. of Architecture. Massachusetts Institute of Technology. Department of Architecture 2012-02-29T16:55:20Z 2012-02-29T16:55:20Z 1992 1992 http://hdl.handle.net/1721.1/69291 26565424 Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1992. Includes bibliographical references (leaves 48-49). The use of a tracer aerosol with a bulk density close to that of air is a convenient way to study the dispersal of pollutants in ambient room air flow. Conventional point measurement techniques do not permit the rapid and accurate determination of the concentration fields produced by the injection of such a tracer into a volume of air. An instantaneous two dimensional distribution would aid in the characterization of flow and diffusion processes in the volume studied, and permit verification of theoretical models. A method is developed to measure such two dimensional concentration fields using a laser light sheet to illuminate the plane of interest, which is captured and processed using current microcomputer-based video image acquisition and analysis technology. Point concentrations, determined optically using extinction of monochromatic illumination projected through the aerosol onto a photo detector, are used to calibrate the captured video linages to detennine actual concentration values. Accuracy, reproducibility, and maximum rate of data acquisition are evaluated by means of theoretical models of ambient air flow in a sealed box with pointinjection of the tracer, and in a duct of circular cross section with constant air velocity under both constant and pulsed injection scenarios. by Frank Revi. M.S. v, 65 leaves eng Massachusetts Institute of Technology M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission. http://dspace.mit.edu/handle/1721.1/7582 Architecture. Measurement of two-dimensional concentration fields of a glycol-based tracer aerosol using laser light sheet illumination and microcomputer video image acquisition and processing Thesis application/pdf Publication unknown unknown <Publication xmlns="https://www.openaire.eu/cerif-profile/1.1/" id="52071b29-7e0a-412f-904a-350bb931798e"> <Type xmlns="https://www.openaire.eu/cerif-profile/vocab/COAR_Publication_Types">http://purl.org/coar/resource_type/c_1843</Type> <Language>eng</Language> <Title>Measurement of two-dimensional concentration fields of a glycol-based tracer aerosol using laser light sheet illumination and microcomputer video image acquisition and processing</Title> <PublishedIn> <Publication> </Publication> </PublishedIn> <PublicationDate>1992</PublicationDate> <Authors> <Author> <DisplayName>Revi, Frank</DisplayName> <Affiliation> <OrgUnit> </OrgUnit> </Affiliation> </Author> </Authors> <Editors> </Editors> <Publishers> <Publisher> <DisplayName>Massachusetts Institute of Technology</DisplayName> <OrgUnit /> </Publisher> </Publishers> <License>http://dspace.mit.edu/handle/1721.1/7582</License> <Keyword>Architecture.</Keyword> <Abstract>The use of a tracer aerosol with a bulk density close to that of air is a convenient way to study the dispersal of pollutants in ambient room air flow. Conventional point measurement techniques do not permit the rapid and accurate determination of the concentration fields produced by the injection of such a tracer into a volume of air. An instantaneous two dimensional distribution would aid in the characterization of flow and diffusion processes in the volume studied, and permit verification of theoretical models. A method is developed to measure such two dimensional concentration fields using a laser light sheet to illuminate the plane of interest, which is captured and processed using current microcomputer-based video image acquisition and analysis technology. Point concentrations, determined optically using extinction of monochromatic illumination projected through the aerosol onto a photo detector, are used to calibrate the captured video linages to detennine actual concentration values. Accuracy, reproducibility, and maximum rate of data acquisition are evaluated by means of theoretical models of ambient air flow in a sealed box with pointinjection of the tracer, and in a duct of circular cross section with constant air velocity under both constant and pulsed injection scenarios.</Abstract> <Access xmlns="http://purl.org/coar/access_right" > </Access> </Publication>