本論文根據華擎1,500c.c.直列四缸四行程缸內直噴(Gasoline direct injection)引擎，建立層狀燃燒(Stratified combustion)下的引擎動態模型。本文藉由量測引擎在改變點火提前角度或是節流閥開度等不同操作點下的各項重要參數建立引擎模型，包含汽缸體積模型、氣體質量流率模型、熱釋放模型、熱傳模型、進排氣歧管動態模型以及汽缸動態模型。層狀燃燒是經由二次噴射來達成，進氣行程中上死點前315°進行第一次的汽油注入，注入總噴油量約3成的稀油，並藉由進氣時的氣流將油氣擴散，而第二次注入是在壓縮行程中上死點前60°注入總噴油量剩餘7成的濃油，並藉由在活塞頂部的Wall-Guided設計將油氣引導至火星塞周圍，使第一噴的油氣將燃燒從火星塞擴散至整個汽缸中，而為了更好的表達出二次噴射所形成的兩階段燃燒，本論文使用雙韋伯函式對熱釋放率進行擬合，並對各操作點擬合出來的參數進行二次擬合，其擬合出的方程式為以點火提前角度以及過量空氣係數為變數的多項式。模型結果與分析中確認了氣體質量模型可以使進入和排出汽缸中的質量相符合，熱釋放模型對所有操作點的實驗數據進行比較，並驗證將熱釋放率參數進行二次擬合依然具備應有的特性，在進氣歧管動態模型驗證其質量以及壓力的變化，在汽缸動態模型中對所有操作點的實驗數據進行比較，以及汽缸內壓力變化的原因進行討論，最後進行步階輸入改變點火時間以及步階輸入改變節流閥開度兩種暫態模擬並對其中特性進行討論，最終模型經由實驗數據的驗證，被認為可以在不同的點火提前角度以及過量空氣係數下，準確地預測各曲軸角度下汽缸壓力以及熱釋放的表現。

Based on 1,500 c.c. in-line four-cylinder four-stroke gasoline direct injection engine, this paper establishes an engine dynamic model under stratified combustion. In this paper, the engine model is established by measuring various important parameters of the engine at different operating points such as changing the spark advance angle or throttle valve opening, including cylinder volume model, gas mass flow rate model, heat release model, heat transfer model , intake and exhaust manifold dynamic model and cylinder dynamic model. Stratified combustion is achieved through secondary injection. The first gasoline injection is performed at 315° before the top dead center in the intake stroke, injecting about 30% of the total fuel injection amount, through the intake air flow at the time diffuses the gasoline, the second injection is 60° before the top dead center in the compression stroke to inject the remaining 70% of the total injection amount, through the Wall-Guided design on the top of the piston guide the gasoline around the spark plug, so that the first injection of gasoline will spread the combustion from the spark plug to the entire cylinder. In order to better express the two-stage combustion formed by the secondary injection, this paper uses double wiebe function to fit the heat release rate and quadratic fitting to the parameters of each operating point, the fitted equation is a polynomial with spark advance and excess air coefficient as variables. In model results and analysis, it is confirmed that the gas mass model can match the mass entering and exiting the cylinder. The heat release model is compared with the experimental data at all operating points, and verifies that the quadratic fitting of the heat release rate parameters is still applicable, and the quality and pressure changes of the intake manifold can be verified in the dynamic model of the intake manifold. The experimental data of all operating points can be compared in the dynamic model of the cylinder, and discuss the reasons for the pressure changes in the cylinder, two kinds of transient simulations, the step input changes of the spark advance and the step input changes of the throttle valve opening, are carried out, and the characteristics are discussed. Finally, the model is verified by experimental data, and it is considered that it can accurately predict the performance of cylinder pressure and heat release at various crankshaft angles under different spark advance and excess air coefficients.

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