VTechWorks staff will be away for the winter holidays starting Tuesday, December 24, 2024, through Wednesday, January 1, 2025, and will not be replying to requests during this time. Thank you for your patience, and happy holidays!
 

Design and Validation of a Proportional Throttle Valve System for Liquid-Fuel Active Combustion Control

Simple item page
dc.contributor.authorSchiller, Noah Harrisonen
dc.contributor.committeechairSaunders, William R.en
dc.contributor.committeememberBaumann, William T.en
dc.contributor.committeememberVandsburger, Urien
dc.contributor.departmentMechanical Engineeringen
dc.date.accessioned2011-08-06T15:58:25Zen
dc.date.adate2003-10-16en
dc.date.available2011-08-06T15:58:25Zen
dc.date.issued2003-10-08en
dc.date.rdate2003-10-16en
dc.date.sdate2003-10-14en
dc.description.abstractHigh-bandwidth fuel modulation is currently one of the most promising methods for active combustion control. To attenuate the large pressure oscillations in the combustion chamber, the fuel is pulsed so that the heat release rate fluctuations damp the pressure oscillations in the combustor. This thesis focuses on the development and implementation of a high-bandwidth, proportional modulation system for liquid-fuel active combustion control. The throttle valve modulation system, discussed in this thesis, uses a 500-um piezoelectric stack coupled with an off-the-shelf valve. After comparing three other types of actuators, the piezoelectric stack was selected because of its compact size, bandwidth capabilities, and relatively low cost. Using the acoustic resonance of the fuel line, the system is able to achieve 128% pressure modulation, relative to the mean pressure, and is capable of producing more than 75% flow modulation at 115 Hz. Additionally, at 760 Hz the system produces 40% pressure modulation and 21% flow modulation with flow rates between 0.4 and 10 gph. Control authority was demonstrated on a single-nozzle kerosene combustor which exhibits a well-pronounced instability at ~115 Hz. Using the modulation system, the fundamental peak of the combustion instability was reduced by 30 dB, and the broadband sound pressure levels inside the combustor were reduced by 12 dB. However, the most important conclusion from the combustion control experiments was not the system?s accomplishments, but rather its inability to control the combustor at high global equivalence ratios. Our work indicates that having the ability to modulate a large percentage of the primary fuel is not always sufficient for active combustion control.en
dc.description.degreeMaster of Scienceen
dc.format.mediumETDen
dc.identifier.otheretd-10142003-151535en
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-10142003-151535en
dc.identifier.urihttp://hdl.handle.net/10919/9843en
dc.publisherVirginia Techen
dc.relation.haspartThesis.pdfen
dc.rightsIn Copyrighten
dc.rights.urihttp://rightsstatements.org/vocab/InC/1.0/en
dc.subjectproportional fuel injectionen
dc.subjectpiezoelectric actuatoren
dc.subjectfuel modulationen
dc.subjectactive combustion controlen
dc.subjecthigh-bandwidth valveen
dc.titleDesign and Validation of a Proportional Throttle Valve System for Liquid-Fuel Active Combustion Controlen
dc.typeThesisen
thesis.degree.disciplineMechanical Engineeringen
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen
thesis.degree.levelmastersen
thesis.degree.nameMaster of Scienceen

Files

Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
Thesis.pdf
Size:
2.57 MB
Format:
Adobe Portable Document Format
Download

Collections

Masters Theses