简介:Self-similarsteadynaturalconvectionthermalboundarylayerflowfromarotatingverticalconetoanisotropicDarcianporousmediumisinvestigatedtheoreticallyandnumerically.Thetransformednon-dimensionaltwo-pointboundaryvalueproblemisreducedtoasystemofcoupled,highlynonlinearordinarydifferentialequations,whicharesolvedsubjecttorobustsurfaceandfreestreamboundaryconditionswiththeMAPLE17numericalquadraturesoftware.Validationwithearliernon-rotatingstudiesisincluded,andalsofurtherverificationofrotatingsolutionsisachievedwithavariationalfiniteelementmethod(FEM).Therotational(spin)parameteremergesasaninversefunctionoftheGrashofnumber.Theinfluenceofthisparameter,primaryDarcynumber,secondaryDarcynumberandPrandtlnumberontangentialvelocityandswirlvelocity,temperatureandheattransferratearestudiedindetail.ItisfoundthatthedimensionlesstangentialvelocityincreaseswhilstthedimensionlessswirlvelocityandtemperaturedecreasewiththeswirlDarcynumber,tangentialDarcynumberandtherotationalparameters.Themodelfindsapplicationsinchemicalengineeringfiltrationprocessing,liquidcoatingandspinningconedistillationcolumns.
简介:ThisworkprovidesacomprehensivetheoreticalanalysisofMHDunsteadyfreeconvectionviscoelasticfluidflowthroughaporousmedium.Themediumistreatedasincompressibleandopticallytransparent.Theflowofthefluidisinitiatedbyshearingactionofthemovingwallwithtimedependentsuction.Radiativeheatflowisconsideredintemperatureequation.Thecouplednonlinearproblemhasbeensolvedasymptotically.Approximatesolutionshavebeenobtainedforthemeanvelocity,meantemperatureusingmultiparameterperturbationtechnique.Theoriginalityofthepresentstudyistoinvestigatetheeffectofviscoelasticpropertyofthefluid(WaltersB?model)ontheflowandheattransferphenomenawhentheflowispermeatedthroughaporousmediumwithuniformporousmatrixsubjecttotransversemagneticfieldandtimedependentfluctuativesuctionattheboundarysurface.Thecaseofviscousflowhasbeendiscussedasaparticularcaseoncomparisonwiththeresultreportedearlieranditisingoodagreement.Flowreversalisindicatedincaseofviscoelasticfluidwithhighheatcapacityinthepresenceofmagneticfield.Thehighercoolingoftheplateincaseofviscoelasticflowalsocausesaflowreversal.