Thispaperstudiesthewall-boundedflowaroundacylindricalatahighReynoldsnumbersbodyinadeterminedcomputationaldomain,withsimulationsofthe3-D,turbulentconcentricannulusflowinastraightpipe.Numericalresultsshowthatareversingzone,appearingasatonguezonewithnestedvelocitieshigherthanthesurroundingarea,existsbehindthecylindricalbody.Theannulusspaceisaregionofhighvelocityandlowpressure.Thezerovelocity,ofcombinedtheX-velocityandtheY-velocity,existsinthecrosssectionsandnovortexsheddingisformedbehindtheattachingcylinders.Amongallinvestigatedeffectingfactors,thediametersoftheattachingandthemaincylindersaffectthewakefeaturebehindthecylindricalbodywhilethemaincylinderlengthdoesnotaffectthedistributiontendencyoftheflowfield.Thediametersofthemaincylinderandthepipeaffectthepressurevaluesandthedistributiontendenciesonthemaincylindersurface.Obviously,theincreaseofthepipediameterreducesthedragcoefficientofthecylindricalbodyandtheincreaseofthediameterofthemaincylinderincreasesthedragcoefficientgreatly.Thenumericalinvestigationoftheconcentricannulusflowprovidesfoundationsforfurtherimprovementsoftheintricateflowstudies.
