| Summary: | 博士 === 國立成功大學 === 航空太空工程學系 === 88 === Behaviors of multiple flame configurations and gasification rates of a convective droplet have appeared in the surveys. These intriguing results associated with other reviews indicated that the unsteadiness of a droplet might have an intrinsic influence on the final state of the droplet in the evolution. However, the detailed studies of dynamic and energetic transience of an isolated droplet still require advanced theoretical analysis. The canonical theory, which has been developed by Chiu since the 1990s, has a heuristic perspective and is expected to create a new route to enhance the knowledge base for the interfacial science. With the additional efforts, the canonical theory has been reinvented to apply to broader applications and realizations, which include the study of dynamic and energetic transience of a droplet. Canonical theory of droplet gasification gives general criteria of ignition and serves to identify all the gasification sub-mechanisms of arbitrary geometry in a stationary or convective environment. The contents of the present thesis include: (i) Reinvent a general expression for the canonical theory in curvilinear coordinates, which extends the canonical theory to broader applications for various flow fields with the general flow geometry; the theoretical development also establishes a compact conjugation with the numerical calculation; (ii) By means of the numerical calculation, thermochemical evolution of a droplet suddenly exposed to a hot environment and a pre-vaporizing droplet confronted by a hotter thermal front are studied to assess the transient characteristics of the ignition, flame bifurcation and scavenging combustion, transition of premixed flame to non-premixed combustion, and the ultimate burnout of an isolated droplet. Meanwhile, the droplet ignition transience, gasification sub-mechanisms, their rate partitions, scenario of ignition transience and their effects on the evolution of a droplet are also studied on the basis of the canonical theory. Areas of future research are also discussed.
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