直噴式增壓柴油機(jī)瞬態(tài)工況燃燒噪聲機(jī)理研究.pdf

1、天津大學(xué)碩士學(xué)位論文直噴式增壓柴油機(jī)瞬態(tài)工況燃燒噪聲機(jī)理研究姓名：張家雨申請(qǐng)學(xué)位級(jí)別：碩士專業(yè)：動(dòng)力機(jī)械及工程指導(dǎo)教師：舒歌群20070601ABSTRACTThecombustionnoiseplaysanimportantroleinthewholenoiseofthedirectinjectiondieselengineThetransientchangeofconditionsfirstlyreflectsthechangeof

2、thein—cylinderprocessoftheintemalcombustionengineInordertostudythephenomenathatthenoisechangesacutelyintransientconditions，itisnecessarytofindouttheeffectmechanismofthetransientconditionsoncombustionnoiseThisdissertation

3、takesaturbochargeddirectinjectiondieselengine笛itsresearchobject，applyingtestingtechnologyandtestingmethodtotheresearchonthecombustionnoiseintransientconditionsItmeasuresthenoisethroughthemethodofnearfieldsoundpressureand

4、obtainscombustionnoisebywayofdesigningtimewindowMeanwhileitmeasulesthecylinderpressure，thepressureofnozzleendandthevibrationsignalItanalyzesthecauseofthedifferencesincombustionnoiseintransientconditionsandstablecondition

5、srespectivelythroughtwodirectfactorswhichinfluencethecombustionnoise：theAerodynamicloadandthehigh—frequencyoscillationofcylinderpressureItshowsthattherateofpressureriseandthehighfrequencyoscillationofcylinderpressurearet

6、hemainfactorswhichinfluencethecombustionnoiseThecombustiondelayperiod，thequantityoffuelinjected，andSOonareindirectinfluencingfactorsofthecombustionnoiseThisdissertationanalyzesthathowthesefactorsvaryintransientconditiona

7、ndstableconditionrespectivelyThoughtthat，thisdissertationthenresearcheshowthesefactorsinfluencethestimuluspropertyofthecylinderpressureandthehighfrequencyoscillationofthecylinderpressure，andhowtheyfurtherinfluencethecomb

8、ustionnoiseintransientandstableconditionrespectivelyTheresearchshowsthatdifferencesinparametersuchasthecombustiondelayperiod，thequantityoffuelinjected，thetemperatureofchamberwallintransientandstableconditionsinthesameloa

9、dandrotationspeedrespectivelyresultinthechangeofcombustionpressure，therateofpressurerise，thefrequencyandamplitudeofthehi曲一frequencyoscillationofcylinderpressure，thereforeresultindifferentcombustionnoiseintransientandstab