An experimental and theoretical study, including frictional and heat transfer effects, of pulsed pressure-gain combustion

dc.contributor.advisorKentfield, John A. C.
dc.contributor.authorCronje, Johannes Stephanus
dc.date.accessioned2005-07-19T21:22:24Z
dc.date.available2005-07-19T21:22:24Z
dc.date.issued1979
dc.descriptionBibliography: p. 221-226.en
dc.description.abstractIt has been noted, from experimental results reported in the literature, that a non-optimised. valveless pulsed pressure-gain combustor of 73 mm diameter has produced a stagnation-pressure rise in excess of 5 percent at a combustor stagnation temperature ratio of 3:1, One of the objectives of the present work was to optimise this pressure-gain configuration and hence explore the possibility of achieving an improved pressure-gain, Two fluidic devices, which capture and redirect all outflow (inlet backflow) leaving the inlet section of the pulsed combustor, were designed for the optimisation task, Various secondary duct systems, coupled to the fluidic device, were constructed and optimised experimentally. Theoretical studies available in the literature show the lack of an adequate analytical tool suitable for designing simple inlet, valveless pulsed combustors. A second objective was therefore, to initiate the analytical approach presented in this study in an attempt to alleviate this shortcoming. The theoretical analysis established a new numerical technique to predict the non-steady flow of a compressible fluid, with frictional and heat transfer effects, in a duct with a spatially varying cross-sectional area. The difference equations derived and the numerical technique, are adaptable to a wide range of unsteady flow problems. The numerical procedure, as applied to the pulsed combustor, incorporates a simple heat release scheme to model the combustion process. Quasi-steady boundary conditions were developed as well as expressions for the pressure and temperature, versus time relationships in the combustion chamber. The numerical technique was found to be capable of converging to cyclic operation within five to six pulsed-combustor cycles as modelled by the computational procedure. The theoretical model produced information resulting in the generation of quantitative evaluations of: mass flows, temperatures, pressures, fuel consumption, thrust developed, fuel air ratios and the influence on the foregoing performance parameters of geometrical changes. It was found that the theoretical predictions obtained compared very well with experimental data gathered from various sources. The main conclusion derived from the experimental portion of the study shows that a stagnation-pressure rise of 5 percent, at a combustor stagnation-temperature ratio of 2.7:1, is the ultimate to be expected from the present pressure-gain configuration having a combustion zone diameter of 73 mm. The complexity of the combustion process in the combustion chamber of a pulsed combustor coupled with the current lack of knowledge associated with mixing, kinetics of reaction and non-equilibrium effects makes a detailed theoretical analysis, based entirely on first principles, of an actual pulsed combustor practically impossible at the present state of knowledge. This situation will, presumably, only be relieved when an adequate combustion model, taking into account the previously mentioned, has been developed.en
dc.description.notesThis title is not available online. Access options are: - consulting the copy from Archives in our reading room in person - https://asc.ucalgary.ca/visiting/ - borrowing a circulating copy from the Library catalogue – https://ucalgary.primo.exlibrisgroup.com/discovery/search?vid=01UCALG_INST:UCALGARY&lang=en
dc.format.extentxxxiv, 307 leaves : ill. ; 30 cm.en
dc.identifier82481065en
dc.identifier.citationCronje, J. S. (1979). An experimental and theoretical study, including frictional and heat transfer effects, of pulsed pressure-gain combustion (Doctoral thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca. doi:10.11575/PRISM/11368en_US
dc.identifier.doihttp://dx.doi.org/10.11575/PRISM/11368
dc.identifier.lccTJ 773 C74 1979 Microficheen
dc.identifier.other82481065en
dc.identifier.urihttp://hdl.handle.net/1880/14943
dc.language.isoeng
dc.publisher.institutionUniversity of Calgaryen
dc.publisher.placeCalgaryen
dc.rightsUniversity of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.
dc.subject.lccTJ 773 C74 1979 Microficheen
dc.subject.lcshCombustion research
dc.subject.lcshGas flow
dc.subject.lcshGas-turbines - Combustion
dc.titleAn experimental and theoretical study, including frictional and heat transfer effects, of pulsed pressure-gain combustion
dc.typedoctoral thesis
thesis.degree.disciplineMechanical Engineering
thesis.degree.grantorUniversity of Calgary
thesis.degree.nameDoctor of Philosophy (PhD)
ucalgary.thesis.accessionTheses Collection 58.002:Box 345 82481065
ucalgary.thesis.notesPLen
ucalgary.thesis.uarcreleasenoen
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