本研究採高活化能近似微擾法，以探究單一分佈複合液滴之噴霧火焰理論解，發展初期僅先考量液滴噴霧對火焰產生內部熱傳的影響；噴霧液滴的組成為內核為水，外層包覆正辛烷的複合液滴，其具有特定的初始液滴半徑與外層燃油質量分率。分析的限制為，噴霧液滴與氣態火焰的質量相比須是相對稀薄的且液滴均一分佈於穩定、層流、低速且遠離化學計量比的貧油或富油之預混火焰中，火焰結構與傳播採一維座標且絕熱系統進行分析。
以往藉由高活化能理論，已提升燃油及惰性物質噴霧對火焰影響的瞭解，然而複合液滴噴霧火焰的理論研究卻是由本論文首次提出，與純質噴霧火焰的差異在於複合液滴具有外層辛烷與內核水滴的兩段氣化過程，對貧油火焰而言，複合液滴噴霧可以由外層辛烷燃燒而對系統提供熱獲得，同時也會因液滴蒸發吸熱而造成熱損失；對富油火焰而言，雖然不會再產生熱獲得，但是由於水與辛烷的潛熱性質差異，液滴的外層燃油質量分率仍然會在噴霧火焰的特性上扮演重要參數。在本論文中，複合液滴噴霧依其外層燃油和內核水滴的氣化區間與火焰的相對位置可被區分為完全預蒸發(CPB)、外層燃油預蒸發(SPB)、以及外層燃油部份預蒸發(SPP)等三種不同之噴霧燃燒模式；換言之，複合液滴噴霧之模式是可以藉由控制液滴的初始尺寸及外層燃油質量分率來達成。此外，兩種臨界模式((CPB)c：液滴恰好在火焰位置蒸發完畢，與(SPB)c：外層燃油恰好在火焰位置蒸發完畢)的複合液滴噴霧或許是未來在應用上的最佳條件，而且為達到符合臨界模式其所對應的臨界參數需相互配合，因此相對有趣且值得探討。
探討過程中，經由將外層辛烷與內核水滴的兩段氣化區間以圖形繪出後，便能清楚顯示複合液滴噴霧之燃燒模式，配合火焰特性的變化，更能體會出由噴霧所造成的內部熱傳，其發生在火焰上游與下游時，對預混火焰產生的影響程度差異。在本文中所包含的參數有外層燃油質量分率( )、液滴的初始尺寸( 或 )、以及噴霧量( )，並分別對貧油與富油火焰進行分析；火焰特性乃是以火焰傳播質量流率( )來表示，其可代表受噴霧影響，火焰強度是增強( >1)、減弱( <1)或甚至造成火焰的熄滅；火焰熄滅現象的發生，則是出現在S型曲線的上轉折點。
最後，經由分析結果之觀察，造成火焰熄滅之複合液滴噴霧的必要條件有二：噴霧必須對火焰造成抑制強度的負效應，以及液滴必須在火焰位置產生夠大的熱損失率。對貧油火焰而言，當 μm或 的情況下，複合液滴噴霧將無法造成火焰的熄滅；對富油火焰而言，火焰熄滅可能發生於SPB、SPP或(SPB)c三種噴霧模式下，本論文最後並試著以圖表示，複合液滴噴霧所將造成火焰熄滅的極限條件。

A monodispersed compound-drop spray flame is investigated by large-activation-energy asymptotic analysis. The present study provides a qualitative insight into the internal heat transfer of a compound-drop spray on a flame. The composition of a compound drop is a water core encased by a fuel shell specified by an initial radius and a shell-fuel mass fraction. The spray shall be dilute and monodispersed in a lean or rich premixed flame which is steady, laminar, low-speed, and off-stomichiometric. The flame structure and propagation is analyzed in an adiabatic one-dimensional coordinate system.
The understanding of fuel or inert spray flames has been improved through the large-activation-energy theoretical works. However, the compound-drop spray flame asymptotic analysis is first developed in this thesis. The difference from a single-component spray is that the compound drop has two gasification processes, namely the shell fuel and the core water. For a lean flame, the compound-drop spray can provide heat gain at the reaction zone and heat loss in the vaporization region. For a rich flame, although the shell fuel and the core water both induce heat loss, the difference in their latent heat makes the shell-fuel mass fraction of the compound drop to play an important role in the spray flame behavior. In this thesis, the compound-drop spray has been divided into the completely pre-vaporized burning (CPB), the shell pre-vaporized burning (SPB) and the shell partially pre-vaporized (SPP) modes by the relative position of gasification zones of the shell fuel and the core water to the flame sheet. In other words, the three spray modes are determined by the initial size and the shell-fuel mass fraction of the compound drops. According to this classification, two critical conditions of CPB and SPB are defined. The critical values of initial radius and shell-fuel mass fraction are interestingly important to be investigated.
Through the illustration of the figures of the shell and core gasification regions, the spray modes can be recognized clearly and a better understanding can be gained that the downstream internal heat transfer has a weaker effect on the flame than the upstream one. The parameters of this compound-drop spray investigation are the shell-fuel mass fraction ( ), the initial radius ( ) or the water-core radius ( ), and the liquid loading ( ). They are analyzed in either a lean or a rich flame. The flame characteristics are represented by the flame propagation mass flux ( ) which indicates that the effect on the flame intensity is enhancement ( >1), suppression ( <1), or extinction, which occurs at the upper turning point of the S-shaped flame propagation mass flux curve.
Furthermore, the necessary conditions of extinction for a compound-drop spray flame are that the spray causes a negative effect and provides a sufficiently heat loss rate at the downstream side of the flame sheet. For a lean spray flame, if μm or , the spray is unable to quench the flame. For a rich spray flame, three extinction patterns were observed; they occur in SPP, SPB or at the critical SPB mode, but not in CPB. The extinction maps of the compound-drop sprays are plotted to demarcate the patterns; also to indicate the limitations and corresponding conditions of flame extinction.

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