CriticalenergyfordirectinitiationofC2H4-O2 mixture

ThedetonationcellsizefortheC2H4-O2 mixturewaspredictedbychemicalkineticsand Ngsmodel.AndtogetherwithLeessurfaceenergymodel,thecriticalenergywasestimatedforthe directinitiationofsphericaldetonationintheC2H4-O2 mixtureunderdifferentinitialpressuresandat differentequivalenceratios.Thedirectinitiationwasperformedviaahighvoltagecapacitorsparkdischargeandthecriticalenergywasaccuratelydeterminedfromthecurrent utputanalysis.Goodagreementwasfoundbetweenthetheoreticalpredictionandtheexperimentalmeasurement. Through steadyZNDanalysesbasedonacomprehensivekineticmechanismandbyusingtheimprovedsemiempiricalcorrelationbyNg, thefactorintherelationbetweenthecellsizeanditsZNDinductionzone length,i.e.,non-dimensionalparameterA,wasdeterminedatdifferentinitialpressuresandequivalenceratiosasfollowing: A=43.815(1+p/p0)-0.12371andA=8.531exp(/3.135)+28.644,respectively. Thecellsizecanbecalculatedultimatelyfromthesecorrelations,andtheexperimentally measuredcellsizesagreewellwiththetheoreticalpredictiondata.Thecellsizeisconsideredasaninputintermediatecharacteristicparameterandusedtoestimatethecriticalenergyfordirectinitiation basedonLeessurfaceenergymodel.Thecombinationofchemicalkineticsandtheoreticalmodels mayformaquantitativetheorytopredictthecriticalenergyfordirectinitiation.Thetheoreticalcurve fitoftheparametricrelationshipbetweenthecriticalinitiationenergyandtheinitialpressureaswell astheequivalenceratioisEc=0.332(p/p0)-2.017andEc=exp[3.951(-1.401)2-1.9],respectively.