Underforcedventilation,thedustdiffusionofundergroundpowerhouseconstructionisinvestigatedusinga3DhighReynoldsnumberk-εmodel.Theinterfacialmomentumtransfersandthewallroughnessinthewallfunctionareconsidered.VentilationinthethirdlayerofundergroundpowerhouseofXiangjiabahydropowerstationisusedasacase.Thegeometricstructurehasadecisiveeffectontheairflowdistribution.Itisconcludedthatthedustconcentrationdecreasesgraduallywiththeincreaseoftheventilationtime.However,iso-concentrationcurveshavethesametendencyafter1800s.Thedustconcentrationmeetstheventilationanddust-preventionhealthstandardafter2300s.ThepredictionbythepresentmodelisconfirmedbytheexperimentalmeasurementbyNakayama.
