Dynamicanalysisoftheclosed-looptransferfunctionintheminiatureneutronsourcereactor(MNSR)OriginalResearchArticle

Theclosed-looptransferfunctionofSyrianminiatureneutronsourcereactor(MNSR)hasbeenmeasuredexperimentallyusingthepromptjumpapproximationtechnique.Analysingthereactorstabilitybehaviour,aphysicalmodelhasbeenformulatedbasedontheopen-loop(neutronics)transferfunctionemployingthelumpedparameterconcepttodescribethereactorthermohydrauliccharacteristics.Thereactorkineticsisdescribedbythepointkineticmodelforone-groupofdelayedneutrons.Inherentinternalfeedbackeffectisconsideredasasinglereactivityfeedbackthatrepresentsthecoolanttemperatureeffect.Comparisonoftheanalyticallyderivedtransfer-functionwiththeexperimentaloneshowsgoodagreement.Stabilityanalysisoftheclosed-looptransferfunctionhasbeenmadeusingtheNyquistcriterionandBodediagram.Routh–HurwitzcriterionhasbeenappliedtoestimatethestabilitylimitoftheMNSRclosed-loop.TheNyquistandBodecriteriahaveshownthattheMNSRclosed-looptransferfunctionisindeedstable.TheRouth–Hurwitzcriterionenabledtheestimationoftheupperlimitoftemperaturefeedbackcoefficientofreactivity.ResultsindicatethatMNSRhashighinherentlysafetyfeatures.Variousrelationshipsthatgovernrelationamongstreactorvariablessuchastheisothermalreactivitycoefficientofmoderatortemperature,temperaturedifferenceacrossthecoreandcoolantflowrateofthenaturalcirculationandmeantimeforheattransfertothecoolanthavebeenconcluded.