為暸解噴霧燃燒系統中複雜的熱流傳輸問題，研究油滴蒸發與燃燒的行為為一門重要的課題。本文所探討的問題便是將一顆常溫油滴置入一高溫熱對流場中，計算在不同環境下，包含不同流場溫度、壓力以及不同油滴初始半徑下，流經一顆油滴所產生的流場暫態變化及其蒸發、燃燒的情形。以下將藉由正準積分理論用以分析計算在流場中各項物理機構對於整體蒸發率的貢獻量，另外針對油滴處在不同流場環境下，各項物理機構的變化情形及所佔的量級角色，以及氣相和液相界面間的傳輸現象做了更加詳細的探討與比較。
研究發現當處於不同環境下，各項物理機構會有相對應的變化，經由觀察這些變化可以了解到在強迫對流下，對流項和化學項是影響蒸發率變化的主要機構；在流場改變時，受熱流場性質變化的影響，會對蒸發率造成抑制的現象。油滴內部僅在初期會對蒸發率造成影響，並且為一負的貢獻量，隨著油滴內部溫度趨於均勻，可發現液相部份對蒸發率的貢獻量漸趨於零；同時藉由氣液相界面分配因子可清楚了解到二相對於蒸發率的貢獻量級比例會隨時間變化的情況，且沿著油滴表面觀察界面分配因子的變化，則可明顯看出火焰模態的演變情形對其有著相當重要的影響。

Research of droplet vaporization and combustion is importance to realize the spray combustion system wherein involving the complex aerothermochemical transport phenomena. In the present thesis, the droplet is exposed in the hot environment, thus the transient heating, vaporization, and combustion of outer gaseous flow and interior liquid flow inside the droplet are investigated by numerical method under various environmental conditions including gaseous temperature, pressure and initial droplet size.
After obtaining numerical exterior and interior thermal flow information, the canonical integral method (CIM) is applied to assist the interpretation of numerical data, then elucidate the physical contributing sub-mechanisms to the droplet vaporization and combustion, thereby calculate the order of magnitude of all terms and finally assess the interior and exterior two-phase transport behaviors and orders by gas and liquid surface modulation factors as time evolves under various flow conditions.
The results by CIM analysis reveal that the convection and chemical reaction terms are the two major driving sub-mechanisms for droplet vaporization and combustion in the forced convection flow field under various conditions. Furthermore, the effect of the variable property term exhibits the negative contribution to reduce the droplet gasification rate. The interior contributions inside droplet including the convection and conduction terms just play the role to complete each other during the droplet heating period and the overall interior effect is negative, and their contributions vanish as the droplet temperature reaches more uniform. Finally, the gas and liquid surface modulation factors are calculated to understand the difference of the contributing order of magnitude between the gaseous and liquid flow fields along the time evolution and the local surface modulation factor along the droplet surface are also shown to investigate the influence from the change of droplet flame modes.

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