简介:Severalindustrialapplicationssuchaselectronicdevices,heatexchangers,gasturbineblades,etc.needcoolingprocesses.Theinternalcoolingtechniqueisproperforsomeapplications.Inthepresentwork,computationalsimulationsweremadeusingANSYSCFXtopredicttheimprovementsofinternalheattransferintherectangularribbedchannelusingdifferentcoolants.Severalcoolantssuchasair,steam,air/mistandsteam/mistwereinvestigated.Theshearstresstransportmodel(SST)isselectedbycomparingthestandardk-ωandOmegaReynoldsStress(ωRS)turbulencemodelswithexperimentalresults.Theresultsindicatethattheheattransfercoefficientsareenhancedintheribbedchannelwhileinjectingsmallamountsofmist.Theheattransfercoefficientsofair/mist,steamandsteam/mistincreaseby12.5%,49.5%and107%overthatofair,respectively.Furthermore,incomparisontoair,theair/mistheattransfercoefficientenhancesbyabout1.05to1.14timeswhenthemistmassfractionincreasesfrom2%to8%,respectively.Thesteam/mistheattransfercoefficientincreasesbyabout1.12to1.27timeshigherthanthatofsteamovertheconsideredrangeofmistmassfraction.
简介:BasedonthetraditionalSmoothedParticleHydrodynamics(SPH)algorithm,thelinked-listsearchalgorithmcombinedwiththevariablesmoothinglengthandsquaresupportdomainwasputforwardtoimprovethecalculationefficiencyandguaranteethecalculationaccuracy.Thephysicalprocessofhighvelocityfragmentimpactonabroadsideliquidcabinwasprogrammedforsimulation.ThenumericalresultsagreedwellwiththoseofthegeneralsoftwareANSYSAUTODYN,whichverifiestheeffectivenessandfeasibilityofthenumericalmethod.Fromtheperspectiveoftheouterplatethicknessoftheliquidcabin,thewidthoftheliquidcabin,andincidentangleofthefragment,theinfluenceoftheseparametersonprotectivemechanismswasanalyzedtoprovideabasisforprotectivedesignofabroadsideliquidcabin.Resultsshowthattheinfluenceofouterplatethicknessisnotobvious;therefore,theconventionaldesigncanbeadoptedinthedesignoftheouterplate.Thewidthoftheliquidcabinhasagreatinfluenceontheresidualvelocityofthefragmentandthewidthoftheliquidcabinshouldbedesignedtobeaswideaspossibleunderthepremiseofmeetingotherrequirements.Thereisacertainincidentangleinwhichthevelocityattenuationofthefragmentismostobvious,andthehigh-pressurezoneneartheinnerplateisasymmetric.Theinnerplateofliquidcabinshouldbestrengthenedaccordingtothehullform,principaldimensions,andvulnerablepoints.