简介：

简介：ThespecificsignofReynoldsstressintheboundarylayeronaflatplateatzeroincidenceisnewlyinterpretedinpresentpaperbasedonthetheoryofvortex-inducedvortex.Itavoidssomeproblemsappearedinatraditionalexplanation,onthebasisofrelationshipbetweenmeanandfluctuatingflowsduetothetransportofmomentum.Throughtheanalysisoflocalflowfieldintheimmediateneighborhoodofwall,thecharacteristicsofReynoldsstressareidentifiedthroughintroducingturbulence-inducedsmall-scalestreamwiseeddiesabovetheflatplate.ThepositiveReynoldsstressistheoreticallyverified.AndsuchnewinterpretationillustratesthatthegenerationofReynoldsstress,aswellasfluctuatingvelocity,isintrinsicallyindependentofthemeanflow.Butitsspecificsignwouldbedeterminedbythemeanflowduetotheinertialforces.Otherfeatures,suchastheintensityrelationshipamongthreecomponentsoffluctuatingvelocity,arealsopresented.