四沖程柴油發(fā)動機

FourstokesEngineofDieselEngine

工程機械專業(yè)英語講授人：李銳鵬What’sthis?這是什么？（導(dǎo)入）WHYANENGINECANWORK????Engine發(fā)動機What’sthis?這是什么？（導(dǎo)入）四沖程汽油機的工作循環(huán)由4個活塞行程組成，即進氣行程、壓縮行程、作功行程和排氣行程。Ithas……（教師講授）Petrol['petr(?)l]n.汽油（英）Gasoline[‘g?s?li?n]n.汽油（美）Diesel['dizl]n.柴油Piston

['p?st(?)n]n.活塞

Ithas……（教師講授）Injector[?n‘d?ekt?]n.噴油嘴

SparkPlug火花塞Ithas……（教師講授）Crankshaft[‘kr??k?ɑ?ft]n.曲軸

ConnectingRod連桿InletValveandExhaustValve進氣閥和排氣閥

Ithas……（教師講授）Camshaft['k?m?ɑ?ft]n.凸輪軸

Whentheyareputtogether,itlookslikethis.Whenitworks當(dāng)它工作時（學(xué)生任務(wù)）FourStrokes四個沖程（教師講授）IntakeStroke進氣沖程CompressionStroke壓縮沖程FourStrokes四個沖程（教師講授）PowerStroke做功沖程ExhaustStroke排氣沖程FourStrokes四個沖程（教師講授）ReadandTranslate讀與譯（學(xué)生任務(wù)）Petrol['petr(?)l]n.汽油（英）Gasoline[‘g?s?li?n]n.汽油（美）Diesel['dizl]n.柴油Piston

['p?st(?)n]n.活塞

Injector[?n‘d?ekt?]n.噴油嘴Crankshaft[‘kr??k?ɑ?ft]n.曲軸ConnectingRod連桿SparkPlug火花塞InletValveandExhaustValve進氣閥和排氣閥

Camshaft['k?m?ɑ?ft]n.凸輪軸

IntakeStroke進氣沖程CompressionStroke壓縮沖程PowerStroke做功沖程ExhaustStroke排氣沖程Translation翻譯（小組作業(yè)）Afour-strokeengine(alsoknownasfourcycle)isaninternalcombustion(IC)engineinwhichthepistoncompletesfourseparatestrokeswhileturningacrankshaft.Intake:Thisstrokeofthepistonbeginsattopdeadcenter(T.D.C.)andendsatbottomdeadcenter(B.D.C.).Inthisstroketheintakevalvemustbeintheopenpositionwhilethepistonpullsanair-fuelmixtureintothecylinderbyproducingvacuumpressureintothecylinderthroughitsdownwardmotion.Compression:ThisstrokebeginsatB.D.C,orjustattheendofthesuctionstroke,andendsatT.D.C.Inthisstrokethepistoncompressestheair-fuelmixtureinpreparationforignitionduringthepowerstroke(below).Boththeintakeandexhaustvalvesareclosedduringthisstage.Power:Thisisthestartofthesecondrevolutionofthefourstrokecycle.Atthispointthecrankshafthascompletedafull360degreerevolution.WhilethepistonisatT.D.C.(theendofthecompressionstroke)thecompressedair-fuelmixtureisignitedbyasparkplug(inagasolineengine)orbyheatgeneratedbyhighcompression(dieselengines),forcefullyreturningthepistontoB.D.C.Thisstrokeproducesmechanicalworkfromtheenginetoturnthecrankshaft.Exhaust:Duringtheexhauststroke,thepistononceagainreturnstoT.D.CfromB.D.Cwhiletheexhaustvalveisopen.Thisactionexpelsthespentair-fuelmixturethroughtheexhaustvalve.Assignment課后作業(yè)電子作業(yè)：（個人作業(yè)）練習(xí)自主開發(fā)的英語連連看游戲（Beginner）。游戲軟件請到百度網(wǎng)盤下載觀看英文視頻HowDieselEnginesWorkPart1，自學(xué)英文單詞，下次課上展示。視頻請到百度網(wǎng)盤下載朗讀作業(yè)：（個人作業(yè)）熟練朗讀本課的重要詞匯（Amateur）。示范音頻請到百度網(wǎng)盤下載翻譯作業(yè)（學(xué)習(xí)小組以電子檔形式提交）：請到百度網(wǎng)盤下