Investigation of the validity of BEM for simulation of wind turbines in complex load cases and comparison with experiment and CFD

摘要

TheaimofthisworkistoinvestigatethevalidityofsimulationcodesbasedontheBladeElementMomentum(BEM)theoryforthreeimportantdesignloadconditions.Thispaperincludesthecasesofyawedinflow,rotortowerinteractionfordownwindturbinesandthestandstillcase.ComputationalFluidDynamics(CFD)andexperimentaldata(whenavailable)areusedfortheevaluationoftheobtainedresults.Fortheyawedinflow,theresultsindicatethatsignificantdeviationsbetweenBEMandexperiments&CFDcanbeobserved.Thisdiscrepancyiscausedbyunsteadyphenomenasuchastheadvancing&retreatingbladeeffectandtheskewedwakeeffect.Inthecaseoftherotorandtowerinteractionofthedownwindturbine,theresultsshowthattheBEMbasedcodeoverpredictsthesectionalforcesintermsofthenormalandtangentialforcesby20%.Inthecaseofstandstill,theevaluationoftheresultsbasedontipdeflectionsshowscleardifferencesintheoutputofbothnumericalapproaches.Whiletheflapwisedeflectionsshowareasonableagreement,theCFD-basedcoupledsolverpredictsmuchlargeredgewisevibrations...