《燃烧学基础》2020春季学期 燃烧学基础 陈正 cz@pku.edu.cn ®北京大李 Peking University 从蜡烛火焰说起 《燃烧学基础》1，绪论 陈正(cz@pku.edu.cn)2
⟹✝ᆜะ ࠔ ୟ cz@pku.edu.cn ޫއक澧ׁ䏝澦 Peking University ࠔ ୟ 澦䏝ׁक澧ͬ ঠ ୟࠔ I`&VQ[KJ[IT Ԅ㵗✑⚡❦䈪䎭
太空中的蜡烛火焰 哪个烧的 更快？ 微重力能够产生更圆的温度更低的火焰。在这张对照图中，正常重力条 件下产生的火焰（左侧和微重力环境下的火焰（右侧）之间的区别可谓一目 了然。与在地球上不同的是，微重力条件下的低密度热气体不会上升。 其结果是，粒子从高温区向低温区扩散等其它过程占据了支配地位。在 太空研究燃烧进一步揭示了有关这种现象的基本物理学原理，进而帮助 研发用于未来太空探索任务的灭火技术。 《燃烧学基础》1，绪论 陈正(cz@pku.edu.cn)5 燃烧：社会发展与科技进步的推动力 競经 第二次工业 第一次工业 燃气轮机、 革命、 火箭发动机 类文明 内燃机 出现 蒸汽机 化学动力学、连 燃烧热化学 续介质理论 使用火 热力学 氧化说 燃素说 史前17世纪 18世纪 19世纪 20世纪 《燃烧学基础》1，绪论 陈正(cz@pku.edu.cn)6
澦䏝ׁक澧ͬ ঠ ୟࠔ I`&VQ[KJ[IT འグѣⲺ㵗✑⚡❦ ᗞ䟽࣋㜭ཏӗ⭏ᴤശⲴᓖᴤվⲴ⚛❠DŽ൘䘉ᕐሩ➗മѝˈ↓ᑨ䟽࣋ᶑ Ԧлӗ⭏Ⲵ⚛❠(ᐖח઼(ᗞ䟽࣋⧟ຳлⲴ⚛❠(ਣח(ѻ䰤Ⲵ४࡛ਟ䉃аⴞ Ҷ❦DŽо൘ൠ⨳кн਼Ⲵᱟˈᗞ䟽࣋ᶑԦлⲴվᇶᓖ✝≄փнՊкॷDŽ ަ㔃᷌ᱟˈ㋂ᆀӾ儈४ੁվ४ᢙᮓㅹަᆳ䗷〻ঐᦞҶ᭟䝽ൠսDŽ൘ ཚオ⹄ウ⟳✗䘋а↕⽪Ҷᴹޣ䘉⿽⧠䊑Ⲵสᵜ⢙⨶ᆖ⨶ˈ䘋㘼ᑞࣙ ⹄ਁ⭘Ҿᵚᶕཚオ᧒㍒ԫ࣑Ⲵ⚝⚛ᢰᵟDŽ ଠѠ✝Ⲻ ᴪᘡϋ 澦䏝ׁक澧ͬ ঠ ୟࠔ I`&VQ[KJ[IT ⟹✝φ⽴Րਇኋф〇ᢶ䘑↛Ⲻ᧞࣑ࣞ ޞ㡠グȽ㡠ཟȽ ⨹ौȽའグ᧘⎁ 㫨⊭ᵪ ⟳≄䖞ᵪǃ ᵪࣘਁ㇝⚛ ᵪ⟳ ≝ौ䈪 ⟹✝✣ौᆜȽ ᆜ࣑✣ ौᆜ࣑ࣞᆜȽ䘔 㔣ԁ䍞⨼䇰 ㅢӂ⅗ᐛѐ 䶟ળȽ⊳䖜Ƚ ཝՍ㺂 ֯⭘⚛ ⟹㍖䈪 ㅢж⅗ᐛѐ 䶟ળȽ㡠⎭Ƚ ⚡䖜 ь㓠 ь㓠 ь㓠 ь㓠 Ӱ㊱ᮽ᱄ ⧦࠰ ࢃਨ ᵪ⟳ ㅢӂ⅗ᐛѐ 䶟ળȽ⊳䖜 ཝՍ㺂 ᐛѐ 㡠⎭Ƚ
燃烧：社会发展与科技进步的推动力 十亿吨油当量 p2018 可再生能源 。水由 efens 核 15 石 power %2%% ·世界总能源的80%来自于燃烧矿物燃料 ·燃烧矿物燃料仍将是能源转换的主要方式 ·绝大部分大气污染物和C02也源自于燃烧 《燃烧学基础》1，绪论 陈正(cz@pku.edu.cn)7 980-2017年中国一次能源消费量及占比 ■煤炭■石油·天然气■水能·核能·其他 30 20 鑫器蜜蜜鑫金宝玉墨鑫晨囂美美篱晨着 《燃烧学基础》1，绪论 陈正(cz@pku.edu.cn)8
澦䏝ׁक澧ͬ ঠ ୟࠔ I`&VQ[KJ[IT ⟹✝φ⽴Րਇኋф〇ᢶ䘑↛Ⲻ᧞࣑ࣞ ь⮂ᙱ㜳ⓆⲺ 80αᶛ㠠ӄ⟹✝⸵⢟⟹ᯏ ⟹✝⸵⢟⟹ᯏԃሼᱥ㜳Ⓠ䖢ᦘⲺѱ㾷ᯯᕅ 㔓ཝ䜞࠼ཝ≊⊗ḉ⢟ૂCO2ҕⓆ㠠ӄ⟹✝ ground air space defense power life home safety ॱӯ ⋩ᖃ䟿 %3 澦䏝ׁक澧ͬ ঠ ୟࠔ I`&VQ[KJ[IT ᒪѣളж⅗㜳Ⓠ⎾䍯䠅খ∊
美国能源结构 Estimated U.S.Energy Consumption in019:100.2 Quads o 《燃烧学基础》1，绪论 陈证(cz@pku.edu.cn)）g A Century of Innovation:1.Electrification Twenty Engineering 2.Automobile 3.Airplane Achievements That 4.Water supply and distribution Transformed Our Lives Radio and television 7.Agricultural mechanization 8.Computers 9.Telephony 10.Air conditioning and refrigeratior ACENTURY OF 11.Highways INNOVATION 12.Spacecraft 13.Internet 14.Imaging 15.Household appliances ha 16.Health technologies 17.Petroleum and Petrochemical industries 18.Lasers and fiber optics 19.Nuclear technologies 20.High performance materials 《燃烧学基础》1，绪论 陈正(cz@pku.edu.cn)10
澦䏝ׁक澧ͬ ঠ ୟࠔ I`&VQ[KJ[IT 㗄ള㜳Ⓠ㔉ᶺ 澦䏝ׁक澧ͬ ঠ ୟࠔ I`&VQ[KJ[IT A Century of Innovation: Twenty Engineering Achievements That Transformed Our Lives 1. Electrification 2. Automobile 3. Airplane 4. Water supply and distribution 5. Electronics 6. Radio and television 7. Agricultural mechanization 8. Computers 9. Telephony 10.Air conditioning and refrigeration 11.Highways 12.Spacecraft 13.Internet 14.Imaging 15.Household appliances 16.Health technologies 17.Petroleum and Petrochemical industries 18.Lasers and fiber optics 19.Nuclear technologies 20.High performance materials 8. Computer 9. Telephony 10.Air condit 11.Highways 12.Spacecraf 13.Internet 14.Imaging
能源问题 从石油转向 海平面上升。 其他棕 全球变暖 长江三角 50 1959 2000 2075 o 898 （Adapted from Stephen&s0cobw,2004） 中国能源需求 燃烧+二氧化碳+温室效应→全球变暖 燃烧→能源耗竭→替代燃料 2010 International energy outlook(US DoE) Oil 40years,NG 60y,coal 380y 《燃烧学基础》1，绪论 陈正(cz@pku.edu.cn)11 C0排放与温室效应 Atmpher Dmcratim and Temperature Change 400 密 350 250 400350300250 200 150100 50 Thousands of years BP(before present) 《燃烧学基础》1，绪论 陈正(cz@pku.edu.cn)12
澦䏝ׁक澧ͬ ঠ ୟࠔ I`&VQ[KJ[IT 㜳Ⓠ䰤从 ᳆ਈ⨳ޘ Ӿ⸣⋩䖜ੁ ަԆ⟳ᯉ 2010 (Adapted from Stephen & Socolow, 2004) ⎭ᒩ䶘рॽ ⟹✝ Į㜳Ⓠ㙍ㄣ Įᴵԙ⟹ᯏ ⟹✝ Įӂ≝ौ⻩ Įᇚ᭾ᓊ Įޞ⨹ ѣള㜳Ⓠ䴶≸ 2010 International energy outlook (US DoE) Oil 40years, NG 60y, coal 380y 澦䏝ׁक澧ͬ ঠ ୟࠔ I`&VQ[KJ[IT &2ᧈ᭴фᇚ᭾ᓊ
The Greenhouse effect A T M P G R E E N H OU S E 2 and is con tion back (G 13 How do heat-trapping gases work? o0agragaac0s2h8 osphenc gases 0000 ☐Carbon dioxide 100 surface warms from the energy back to the atmosphere as infrared h8a8n9yaaS space.When gre se gases aharection,incuihg6adk concentrationofa he nhous Wavelength (um) Earth. 名9新s院a 《燃烧学基础》1，绪论 陈正(cz@pku.edu.cn)14
澦䏝ׁक澧ͬ ঠ ୟࠔ I`&VQ[KJ[IT 澦䏝ׁक澧ͬ ঠ ୟࠔ I`&VQ[KJ[IT How do heat-trapping gases work? The energy from the sun that reaches Earth's surface is mostly "shortwave" radiation - mostly visible light. This energy passes freely through the atmosphere and is absorbed by Earth’s surface. The surface warms from the energy input, and some of its heat projects back to the atmosphere as infrared radiation. The greenhouse gases in the atmosphere absorb 95% of the energy in infrared radiation, allowing only 5% to pass into space. When greenhouse gases absorb energy, heat is released in all directions, including back towards Earth. As the concentration of greenhouse gases increases, this “insulating blanket” thickens, further warming the Earth.
The Top Five Climate-Changing Gases n dioxide (CO) -level ozone(O Heat-Trapping Ga Carbon dioxide(CO Methane (CH,) Low-level ozone (O. Halogenated carbor Halogenated carbons Methane (CH) Nitrous oxide (NO Nitrous oxide(NO 《燃烧学基础》1， 5 能源转换→大气污染 ~1亿吨污染物排放年 C02 UHC SOx Particulates 0 《燃烧学基础》1，绪论 陈正(cz@pku.edu.cn)16
澦䏝ׁक澧ͬ ঠ ୟࠔ I`&VQ[KJ[IT The Top Five Climate-Changing Gases 澦䏝ׁक澧ͬ ঠ ୟࠔ I`&VQ[KJ[IT 㜳Ⓠ䖢ᦘ ė ཝ≊⊗ḉ CO2 SOx NOx UHC Particulates ~1ӯ⊑ḃ⢙ᧂ᭮/ᒤ SOx NOx
大气污染 Big concern...thick pollution hides building in Beijing 《燃烧学基础》1，绪论 陈正(cz@pku.edu.cn)17 能源转换 一辆总重为1吨的汽车以100公里/小时的速度行驶，其 动能相当于燃烧多少汽油释放的能量？ A,一勺 B,一杯 一瓶 汽车动能E=0.5x1000x(100/3.6)2≈0.4x106J 汽油(CgH1g)燃烧放热量： CgH1g+12.5(02+3.76N2)→8C02+9H20+47N2(+48x106J/kgfue1.) 二两米饭vs.二两白酒？ 《燃烧学基础》1，绪论 陈(cz@pku.edu.cn18
澦䏝ׁक澧ͬ ঠ ୟࠔ I`&VQ[KJ[IT ཝ≊⊗ḉ Big concern … thick pollution hides building in Beijing 澦䏝ׁक澧ͬ ঠ ୟࠔ I`&VQ[KJ[IT 18 㜳Ⓠ䖢ᦘ ж䖼ᙱ䠃Ѱ ⎭ᒩ䶘рॽ ਫ਼Ⲻ⊳䖜ԛޢ䠂ቅᰬⲺ䙕ᓜ㺂催θެ ࣞ㜳ᖉӄ⟹✝ཐቇ⊳⋯䠀᭴Ⲻ㜳䠅ϋ $θжर %θжᶥ &θж⬬ ⊳䖜ࣞ㜳 (N [[ Ŋ [ - ⊳⋯ &+ ⟹✝᭴✣䠅φ &+ 21 ė&2 +21 [ -NJIXHO ӂњ㊩侣 YVӂњⲳ䞈 " [
能源利用效率：汽车 85%,35%,10%,1%? 2.6% 4.2% 《燃烧学基础》1，绪论 陈证(cz@pku.edu.cn)19 内燃机热效率提高 Where does the energy go? Transionofthemalefcencycdgasolneengne Thermal effici oduced engine:max.-40% 2000 2010 02 Gross thermal efficiency ~37.6% (0ida2017刀 Ideal Carnot efficiency ~1-300/1800=83% Otto cycle efficiency:68%(compression ratio of 17) 《燃烧学基础》1，绪论 陈正(cz@pku.edu.cn20
澦䏝ׁक澧ͬ ঠ ୟࠔ I`&VQ[KJ[IT 㜳Ⓠ⦽᭾⭞φ⊳䖜 20.4ˁ 85%, 35%, 10%, 1% ? 0.4ˁ 澦䏝ׁक澧ͬ ঠ ୟࠔ I`&VQ[KJ[IT ⟹ᵰ✣᭾⦽ᨆ儎 20 Gross thermal efficiency ~ 37.6% Ideal Carnot efficiency ~ 1-300/1800=83% Otto cycle efficiency: 68% (compression ratio of 17) (lida 2017)
内燃机热效率提高 Where does the energy go? University of Wisconsin RCCI low temperature combustion engine Gross thermal efficiency ~37.6% Gross thermal efficiency:59.7 %/o (Reitz et al.2012) .Ideal Carnot efficiency ~1-300/1800=83% .Otto cycle efficiency:68%(compression ratio of 17) 《燃烧学基础》1，绪论 陈正(cz@pku.edu.cn21 Low temperature combustion Newton's cooling equation >Super-Lean burn q(0)=A-h()(Tgas(0)-Tsurface(0)] Reduction o Super-Lean erating High turbulent flow (=20~50 m/s,u'=5 m/s) High EGR (EGR rate =20 % (ida2017) 《燃烧学基础》1，绪论 陈正(cz@pku.edu.cn)22
澦䏝ׁक澧ͬ ঠ ୟࠔ I`&VQ[KJ[IT ⟹ᵰ✣᭾⦽ᨆ儎 21 Gross thermal efficiency ~ 37.6% Ideal Carnot efficiency ~ 1-300/1800=83% Otto cycle efficiency: 68% (compression ratio of 17) Gross thermal efficiency˖ 59.7 % University of Wisconsin RCCI low temperature combustion engine (Reitz et al. 2012) 澦䏝ׁक澧ͬ ঠ ୟࠔ I`&VQ[KJ[IT Low temperature combustion (lida 2017)