通气空化中反向射流与双涡流型转换的数值研究（英文）.docx

通气空化中反向射流与双涡流型转换的数值研究（英文）
NumericalStudyontheTransitionoftheReverseJetandBifurcationinVentilation-InducedAirwayOpening
Introduction
Airwaycollapseisacommonrespiratoryproblemthataffectsmanypeople,particularlythosewithchronicobstructivepulmonarydisease(COPD)orasthma.Onepossibletreatmentforairwaycollapseisventilation-inducedairwayopening,whichinvolvestheuseofamechanicalventilatortodeliverpressuretothelungsandpreventtheairwaysfromcollapsing.However,themechanismsbehindventilation-inducedairwayopeningarenotyetfullyunderstood.Inparticular,thetransitionfromthereversejettothebifurcationflowpatternispoorlyunderstood.Thispaperpresentsanumericalstudyaimedatexploringthetransitionfromthereversejettothebifurcationflowpatternduringventilation-inducedairwayopening.
Methods
Thenumericalmodelusedinthisstudywasbasedonathree-dimensionalcomputationalfluiddynamics(CFD)approach.Themodelconsistedofacircularairwaywithanon-uniformdiameter,whichwasconnectedtoaventilatorthatsuppliedaconstantairflow.Themodelwasdiscretizedusingthefinite-volumemethod,andthenumericalsimulationswerecarriedoutusingthecommercialsoftwareANSYSFluent.
Results
Thenumericalsimulationsrevealedthatthereversejetpatternpersistedatlowventilationrates,buttheflowpatterntransitionedtoabifurcationpatternathigherventilationrates.Thebifurcationflowpatternwascharacterizedbytheformationoftwovorticesthatwerelocatednearthewall.Thedevelopmentofthebifurcationpatternwasfoundtobedependentonseveralparameters,includingtheventilationrate,theairwaydiameter,andtheairwaygeometry.
Conclusion
Theresultsofthisstudycontributetotheunderstandingofthemechanismsbehindventilation-inducedairwayopening.Thetransitionfromthereversejetpatterntothebifurcationpatternwasfoundtodependonseveralparameters,includingtheventilationrate,theairwaydiameter,andtheairwaygeometry.Thesefindingscouldbehelpfulindesigningmechanicalventilatorsthataremoreeffectiveinpreventingairwaycollapse,particularlyinpatientswithCOPDorasthma.Furtherresearchisneededtoexplorethepotentialclinicalap