Author/Authors :
H.Suresan، نويسنده , , S.Jayanti، نويسنده ,
Abstract :
Withtheincreasinguseofcomputationalfluiddynamics(CFD)-basedsimulationsintheassessmentofthermalhydraulicbehaviourofnuclearreactors,thereisaneedtobenchmarkthepredictionsofCFDcodes.ThecaseofafrictionlessU-tubemanometer[Ransom,V.,1992.Oscillatingmanometer.In:Hewitt,G.F.,DelhayeJ.M.,ZuberN.(Eds.),MultiphaseScienceandTechnology,vol.6.Hemisphere,NewYork,USA,p.591]hasbeenpreviouslyusedasatestcasetobenchmarkthedispersiveanddissipativecharacteristicsofanumericalprediction.Inthepresentpaper,thiscaseisextendedtocovertwonewaspectsthatareoftenfoundinnuclearreactorsystems:variabledensityanddissipation.Throughatheoreticalmodel,itisshownthatthedynamicbehaviourofthenewsystemismorecomplicatedthanthatofaconstant-densityfrictionlessU-tubemanometer.Experimentsofthetestcasehavebeencarriedouttosubstantiatetheessentialfeaturesoftheresponse.CFDsimulationsofthesystemshowbothdissipativeanddispersiveerrorscomparedtothetheoreticalresult.Theresultscanthereforeserveasausefulbenchmarkforcomputercodesusedtostudythethermalhydraulicsofnuclearreactorsystems,especiallyinevaluatingtheroleofnumericaldampinginsystemsinwhichphysicaldampingexistsinherently.
