廢氣再循環(huán)對(duì)壓力波增壓器平均價(jià)值建模的影響外文翻譯-wenkub
2023-05-19 02:59:31 本頁(yè)面
【正文】 supercharger. It calculates a simplified pressure wave process based on the relations of the linear onedimensional gas dynamics neglecting the fast dynamics of the pressure wave process. It is validated by the identification of four physically motivated model parameters. As a result, the nonmeasurable leakage losses of the pressure wave supercharger, the nonmeasurable mixing zone length,and its profile between exhaust gases and fresh air can be determined. The validated model of the pressure wave supercharger shows an error on the order of 5%. The developed mean value system model of a pressure wave supercharged SI engine is a simulation tool. The tool may be used for system analysis, system optimization, and model based controller design in the future. Introduction 1 Supercharging an SI Engine Downsizing and Supercharging for Minimal Fuel Consumption Modern spark ignition (SI) engines are required to be equipped with a threeway catalyst in order to meet the current emission limits. Consequently, they have to be operated with stoichiometric airtofuel ratios. The engine torque thus may be controlled only by changing the intake manifold pressure, ., the throttle reduces the level of ambient pressure by energy dissipation to the level of intake manifold pressure. The engine then works at partload conditions, which are characterized by a negative pressure difference over the engine: Pim— Pem0: throttled engine operation The negative pressure difference between intake and exhaust manifolds causes pumping losses for the engine. This is the main reason why naturally aspirated SI engines have a poor efficiency at partload conditions. Among various approaches toward improving this situation several possibilities are found: burn engines with direct injection of gasoline engine speed concept and supercharging for high engine speed only and supercharging over entire engine speed range The concept 1 tries to reduce the fuel consumption by a lean engine operating mode which is still a subject of current research and therefore not further discussed here. In contrast, the engine concepts 2, 3, and 4 try to avoid the pumping losses of the engine by reducing the engine displacement. Compared to a regular SI engine, the downsized engine more often operates at high loads where the throttling losses hardly occur. This leads to negligible pumping losses. The engine then operates near its most economical operating point. The engine power lost by downsizing may be recovered by: 只有一個(gè)不切實(shí)際的簡(jiǎn)短閉合時(shí)間，氣體閥內(nèi)的氣體體積影響著它的動(dòng)態(tài)壓力。反射效率 據(jù)不完全推測(cè)，壓力波增壓器的泄漏損失不包括壓氣機(jī)輪，非計(jì)量混合區(qū)的長(zhǎng)度和通過(guò)識(shí)別模型參數(shù)的廢氣氣體比例。該模型計(jì)算輸出值作為衡量壓力波增壓器壓力和溫度的一種渠道和增壓器的實(shí)際轉(zhuǎn)速?；谝痪S線性氣體動(dòng)力學(xué)理論 ,壓力波增壓器模型計(jì)算出一個(gè)簡(jiǎn)化的壓力波程序和相應(yīng)的壓力波圖。而“油門(mén)”描述了靜態(tài)的代數(shù)關(guān)系。 4． 壓力波增壓器的模型仿真工具在短時(shí)間內(nèi)的相對(duì)誤差要小于 10%。因此，為了保證壓力波汽油機(jī)的動(dòng)力操控性能，必須避免不良的廢氣再循環(huán)。 GPC 執(zhí)行機(jī)構(gòu)不僅通過(guò)控制發(fā)動(dòng)機(jī)進(jìn)氣歧管壓力來(lái)避免抖動(dòng)，而且也擴(kuò)大了汽油機(jī)運(yùn)行時(shí)不發(fā)生泵氣損失的范圍。為了保證良好的操控性，發(fā)動(dòng)機(jī)扭矩在增壓器同步或是不同步的時(shí)候不發(fā)生變化。 體積流量的不同，加上渦輪機(jī)前的實(shí)際壓力、溫度和渦輪轉(zhuǎn)速，造成渦輪機(jī)的負(fù)荷損失。相對(duì)渦輪增壓器，對(duì)同樣的小型發(fā)動(dòng)機(jī)，壓力波增壓器比預(yù)期泄漏損失要小。渦輪機(jī)的幾何尺寸太小會(huì)造成渦輪增壓器在渦輪機(jī)上有較高的泄漏損失。因此，增壓汽油機(jī)可減少 燃料消耗。渦輪增壓 上述環(huán)境壓力加大進(jìn)氣歧管壓力 由于發(fā)動(dòng)機(jī)在高速運(yùn)行時(shí)引起的噪聲，第一個(gè)概念對(duì)客車(chē)來(lái)說(shuō)不是一個(gè)適當(dāng)?shù)倪x擇。相對(duì)普通汽油機(jī)，精簡(jiǎn)發(fā)動(dòng)機(jī)更經(jīng)常在節(jié)流不易損失的高負(fù)荷狀態(tài)下運(yùn)行，這導(dǎo)致了泵氣損失可以忽略不計(jì)。發(fā)動(dòng)機(jī)在部分負(fù)荷條件下工作的負(fù)壓差特點(diǎn)： Pim— Pem﹤ 0：節(jié)流發(fā)動(dòng)機(jī)運(yùn)轉(zhuǎn) 進(jìn)氣管和排氣管之間的負(fù)面壓力差造成發(fā)動(dòng)機(jī)的吸氣損失。該工具可用于系統(tǒng)分析和系統(tǒng)優(yōu)化，并應(yīng)用于模型控制器設(shè)計(jì)。由四個(gè)物理模型參數(shù)驗(yàn)證識(shí)別。這解釋了為什么壓力波增壓器在凈化時(shí)負(fù)荷會(huì)惡化。為了保證良好的操控性，廢氣再循環(huán)必須避免。相比自然吸氣式汽油機(jī)，小型增壓汽油機(jī)工作在中等負(fù)荷和低負(fù)荷范圍間的泵氣損失更小，更為有效。浙江師范大學(xué)本科畢業(yè)設(shè)計(jì) (論文 )外文翻譯 譯文： 廢氣再循環(huán)對(duì)壓力波增壓器平均價(jià)值建模的影響 菲利克斯 壓力波增壓器可能是精簡(jiǎn)增 壓汽油機(jī)的一個(gè)代表。因此，所提出的工作目標(biāo)是建立模型，并排除排氣壓力波增壓器內(nèi)氣體循環(huán)的影響。模型的推斷表明，小型氣閥門(mén)關(guān)閉過(guò) 快會(huì)導(dǎo)致更難凈化。因此，壓力波增壓器的泄漏損失和混合區(qū)的長(zhǎng)度不可測(cè)量，廢氣和新鮮空氣才能被分辨出來(lái)。 簡(jiǎn)介 1 增壓汽油機(jī) 精簡(jiǎn)和最小油耗增壓 現(xiàn)代火花點(diǎn)火（汽油）發(fā)動(dòng)機(jī)都必須具有
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