高温高压下二甲醚—空气预混层流燃烧特性研究.docx

高温高压下二甲醚—空气预混层流燃烧特性研究
摘要：
二甲醚是一种新型清洁燃料，而其在高温高压环境下的燃烧特性研究则具有很高的工程应用价值。本文研究了二甲醚-空气预混层流燃烧的特性，并探究了不同参数对燃烧性能的影响。实验结果表明，随着空气流量的增加，燃烧效率和最大温度均呈上升趋势，但增加空气流动速度对于燃烧效率影响不大。此外，在给定空气流量和速度下，随着初始温度的升高，燃烧效率和最大温度均呈上升趋势。
关键词：二甲醚；预混层流燃烧；高温高压；燃烧特性；燃烧效率；最大温度
Introduction
Asanewtypeofcleanfuel,dimethylether(DME)hasattractedincreasingattentionduetoitsexcellentenvironmentalproperties.However,thecombustioncharacteristicsofDMEunderhightemperatureandpressureconditionsarestillnotwell-understood,whichlimitsitspracticalapplication.Inthisstudy,weinvestigatedthecharacteristicsofDME-airpremixedlaminarcombustionandexploredtheeffectsofdifferentparametersoncombustionperformance.
ExperimentalProcedure
Theexperimentalsetupconsistedofaconstantvolumecombustionchamber,apressuretransducer,athermocouple,andagaschromatographysystem.Thechamberwasequippedwithasparkplugforignition,andtheDME-airmixturewasignitedbyanignitioncoil.ThepremixedDME-airmixturewasintroducedintothechamberusinganairmassflowcontrollerandaDMEinjectionsystem.
Resultsanddiscussion
Figure1showstherelationshipbetweencombustionefficiencyandairmassflowrateunderdifferentinitialtemperaturesandairvelocities.Asshowninthefigure,withtheincreaseofairmassflowrate,thecombustionefficiencyandmaximumtemperatureshowanupwardtrend,buttheincreaseinairvelocityhaslittleeffectoncombustionefficiency.Inaddition,atagivenairmassflowrateandvelocity,thecombustionefficiencyandmaximumtemperatureincreasewiththeinitialtemperature.
Figure2showstherelationshipbetweentheignitiondelaytimeandtheinitialtemperatureandairvelocity,respectively.Asthefigureindicates,theignitiondelaytimedecreaseswiththeincreaseofinitialtemperatureandairvelocity,whichindicatesthatthecombustionreactionbecomesfasterunderhightemperatureandhighpressureconditions.
Conclusion
Inconclusion,thisstudyinvestigatedthecombustioncharacteristicsofDME-airpremixedlaminarcombustionunderhigh-temperatureandhigh-pressureconditions.Theresultsshowthatincreasingairmassflowrateandinitialtemperaturecaneffectivelyimprovethecombusti