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Wai K. Cheng. Pritchard, Joseph James Massachusetts Institute of Technology. Department of Mechanical Engineering. Massachusetts Institute of Technology. Department of Mechanical Engineering 2014-06-13T22:37:11Z 2014-06-13T22:37:11Z 2014 2014 http://hdl.handle.net/1721.1/87963 880688538 Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2014. Cataloged from PDF version of thesis. Includes bibliographical references (pages 69-71). An experimental study was performed to investigate the effects of secondary air injection (SAI) on particulate matter (PM) emissions. SAI was developed to reduce hydrocarbon (HC) emissions and has been shown to be effective as a strategy to reduce HC emissions at cold-start. In general, cold-start emissions have become an increasingly important problem due to new, more stringent vehicle emissions regulations. Direct-injection, spark-ignition (DISI) engines, which emit high levels of PM, are growing in popularity because of their fuel efficiency improvements. Meeting PM emissions becomes a more difficult task due to more stringent standards and the greater adoption of DISI engines. This study seeks to investigate the potential use of SAI to reduce PM emissions in the exhaust system. Engine based experiments were conducted using a 2.0 L, turbocharged, DISI General Motors LNF engine. The engine was outfitted with a secondary air injection system and several thermocouples to measure exhaust stream temperature. A TSI Model 3934 Scanning Mobility Particle Sizer (SMPS) was used to measure particle emissions at various engine operating conditions and secondary air rates. PM reductions were observed for the engine conditions and SAI flow rates that were tested. The maximum particle number reduction achieved was 80%. Particle number and particle volume reduction were observed to correlate well with exhaust enthalpy release. by Joseph James Pritchard. S.M. 71 pages 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 Mechanical Engineering. The effects of secondary air injection on particulate matter emissions Thesis application/pdf Publication unknown unknown <Publication xmlns="https://www.openaire.eu/cerif-profile/1.1/" id="3fc20fa1-7dfc-4fd4-924b-33f8d06c75af"> <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>The effects of secondary air injection on particulate matter emissions</Title> <PublishedIn> <Publication> </Publication> </PublishedIn> <PublicationDate>2014</PublicationDate> <Authors> <Author> <DisplayName>Pritchard, Joseph James</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>Mechanical Engineering.</Keyword> <Abstract>An experimental study was performed to investigate the effects of secondary air injection (SAI) on particulate matter (PM) emissions. SAI was developed to reduce hydrocarbon (HC) emissions and has been shown to be effective as a strategy to reduce HC emissions at cold-start. In general, cold-start emissions have become an increasingly important problem due to new, more stringent vehicle emissions regulations. Direct-injection, spark-ignition (DISI) engines, which emit high levels of PM, are growing in popularity because of their fuel efficiency improvements. Meeting PM emissions becomes a more difficult task due to more stringent standards and the greater adoption of DISI engines. This study seeks to investigate the potential use of SAI to reduce PM emissions in the exhaust system. Engine based experiments were conducted using a 2.0 L, turbocharged, DISI General Motors LNF engine. The engine was outfitted with a secondary air injection system and several thermocouples to measure exhaust stream temperature. A TSI Model 3934 Scanning Mobility Particle Sizer (SMPS) was used to measure particle emissions at various engine operating conditions and secondary air rates. PM reductions were observed for the engine conditions and SAI flow rates that were tested. The maximum particle number reduction achieved was 80%. Particle number and particle volume reduction were observed to correlate well with exhaust enthalpy release.</Abstract> <Access xmlns="http://purl.org/coar/access_right" > </Access> </Publication>