201458 12.3 Other Emissions Control Devices (其他帅放物的拉制黄里) 高生 重的请 小丸地林泰建同向 理花难同气难骨 门同绿量礼 4一购车角1一书备-中 @R冷大？ 窗包冷大 学精大汽单自 窗凡冷复 同精大养汽有 24E它行提经生dE如 工.浪 4IsO压doctie catdytie cmer重R化话为 氢ad金e Fiter DP格s 2 1子 2五48 2445 I Characirritics af Direl engint emiiess 上EG风的k 里期有大销红中减用 415 图出空警有n■ ad山emane rilyanlodan inhigh. DiISeah pasnc 芒出行好 回职 . ▣回 宝提增u一 VIDEO-EGB 包日冷大餐 24g R海子 245 @R冷大 245 限大汽2014/5/8 3 19/45 同济大学汽车学院 (1) Gasoline evaporation control system (汽油蒸发控制系统) § 12.3 Other Emissions Control Devices (其他排放物的控制装置) Function: prevent the evaporation of fuel in fuel tank and the carburetor float bowl(化油器浮子室) diffusing into air and causing pollution. Solution: collect the gasoline vapor and store it in the activated carbon tank(活 性炭罐), then send it into cylinder and be burnt when the engine is started. 20/45 同济大学汽车学院 燃油蒸发（EVAP）控制系统 1-汽油箱 2-燃油泵 3-蒸发阀 4-双通阀 5-碳罐 6-EVAP控制电磁阀 7-进气软管 -节气门 9-滤网 10-量孔 21/45 同济大学汽车学院 (2) Positive crankcase ventilation system (PCV) 强制式曲轴箱通风装置（ PCV系统） Fundamental: When engine is working, send part of the fresh air from the air filter(空气滤清器) to cylinder head cover(气缸盖罩) by the hose(软管), then the air go into the crankcase(曲轴箱) through the hole that is connected cylinder head and body, and mix with crankcase gas. finnaly,the mixtures go into the intake manifold through the PVC valve. 22/45 同济大学汽车学院 23/45 同济大学汽车学院 (3) Constant temperature of intake charge (恒温进气) To supply a high temperature and guarantee mixture form well in cold start or light load. The vacuum degree of intake manifold affects on the vacuum control membrane box 7, and dominates control valve8 open or close. (进气管真空度作用在真空控 制膜盒7上，控制控制阀8开大 或关小) 24/45 同济大学汽车学院 1. Characteristics of Diesel engine emissions; 2. EGR system; 3. Diesel oxidation catalytic converter (柴油氧化催化转化器); 4. The NOx reduction catalytic converter (NOx还原催化转化器); 5. Diesel Particulate Filter (DPF)颗粒捕捉器. §12.4 Emissions Control Devices in Diesel Engine (柴油机的排放控制装置) 25/45 同济大学汽车学院 Features: (1) have no fuel evaporative emissions problem; (2) compared with gasoline engine, HC and CO emissions are much less, and the NOx emission is in the same order of magnitude(同一数量级); (3) particulate matter (PM) emission is high. Difficult points: (1) the exhaust is always in the oxidation atmosphere (excess air coefficient ＞ 1), the NOx reduction is hard;废气总是处于氧化氛围（过量空气系数大于1） 中，NOx难以还原； (2) the exhaust temperature is lower than that of gasoline engine exhaust temperature, soot oxidation is hard;排气温度明显低于汽油机的排气温度，碳 烟难以氧化 (3) the exhaust contains a lot of SOx and particles, cause catalyst poisoning easily.排气中含有大量的SOx和微粒，容易导致催化剂中毒 1 Characteristics of Diesel engine emissions 26/45 同济大学汽车学院 27/45 同济大学汽车学院 2 EGR system Q the quanlity of ch e o the cylinder with EGR Q the quanlity of ch e o the cylinder without EGR Q Q Q EGR rate EGR W OEGR W OEGR W OEGR EGR arg int arg int 100% / / /         Low pressure circuit type (低压回路方式)  High pressure circuit type (高压回路方式) Internal EGR External EGR EGR Types: