Studies of single and multiple impinging radial jet reattachment flames /
A Radial Jet Reattachment Combustion (RJRC) nozzle forces primary combustion air to exit radially from the combustion nozzle and to mix with gaseous fuel in a highly turbulent recirculation region generated between the combustion nozzle and impingement surface. High convective heat transfer and low...
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| Format: | Thesis Book |
| Language: | English |
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[Place of publication not identified] :
[publisher not identified] ;
1996.
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| Online Access: | http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=739363411&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | A Radial Jet Reattachment Combustion (RJRC) nozzle forces primary combustion air to exit radially from the combustion nozzle and to mix with gaseous fuel in a highly turbulent recirculation region generated between the combustion nozzle and impingement surface. High convective heat transfer and low NO, pollutant formation, as well as improved fuel/air mixing, characterize this external mixing combustor for use inimpingement flame heating processes. An experimental program was undertaken in order to understand the fundwnental physical processes involved with the RJRC phenomena. A large prototype RJRC nozzle was shown to be superior to a conventional in-line flame jet nozzle in terms of uniformly heating a surface with minimal formation of gaseous air pollution. In addition, the NO,, reducing characteristics of the RJRC nozzle were identified and discussed. The results of the comparison study were used to develop a small practical RJRC nozzle, scaled down 60 percent from the large RJRC nozzle. Lean blow-out limits for the small practical nozzle were determined, based on the four major nozzle operating parameters: 1) fuel Reynolds number, 2) fuel equivalence ratio, 3) air exit gap width, and 4) nozzle-to- plate spacing. Statistical design and analysis of experiments were used to identify an ideal operating condition over the ranges of the four main operating parameters. While operating under the ideal condition, the extent of the RJRC combustion zone was identified through localized. measurements of gas velocity, surface pressure, gas temperature, surface temperature and surface heat flux. A pair of practical RJRC nozzles was also studied for flames which were highly, moderately, and weakly interactive. Local surface heat flux and temperature profiles were determined for the RJRC nozzle pair, and an optimal between-nozzle spacing was identified based on overall heat transfer data. Gas temperatures for the nozzle pair operating at the optimal between-nozzle spacing revealed the presence of one main flame jet and one secondary flame jet. In summary, the results of this dissertation provide valuable fundamental knowledge regarding the physics of the RJRC combustion process for a single RJRC nozzle as well as a pair of RJRC nozzles. |
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| Item Description: | Vita. "Major Subject: Mechanical Engineering". "August, 1996". |
| Physical Description: | xv, 171 leaves : illustrations ; 28 cm. Issued also on microfiche from University Microfilms Inc. |
| Bibliography: | Includes bibliographical references: pages 133-137. |