HT-7托卡馬克上低雜波電流驅動下鋸齒不穩(wěn)定性的研究.pdf

1、中國科學院合肥物質科學研究院博士學位論文HT7托卡馬克上低雜波電流驅動下鋸齒不穩(wěn)定性的研究姓名：孫有文申請學位級別：博士專業(yè)：等離子體物理指導教師：萬寶年20070531InvestigationofthesawtoothinstabilityinLHCDplasmasonHT7tokamakAbstractAbstractYouwenSUN(PlasmaPhysics)DirectedbyProfBaonianWANAnewoscil

2、lation，withm／n=1／1，isobservedonthesawtoothrampphasewithlowerhybridcurrentdrive(LHCD)ontheHT7tokamakThismodeappearsduringthesawtoothrampphase，saturates，dampsandfinallydisappearsbeforetheappearanceoftheprecursoroscillation

3、softhesubsequentsawtoothcollapseForthepurposeofdistinguishingfromtheprecursoroscillationandthepostcursoroscillation，wecallit“mid—oscillation”Themid—oscillationusuallydoesnottriggerthesawtoothcrash，anditsnonlinearevolutio

4、nquiteresemblestheresistivetearingmode。Theappearanceofthismodesuggeststhatthetriggeringthresholdofthesawtoothcrashisdifferentfromthatofthem=lmode，whichcan’tbeexplainedbythePorcelli’SsawtoothtriggeringmodelThemechanismsof

5、excitingandfinalstabilizationofthemodeareinvestigatedboththeoreticallyandexperimentallyinthisdissertationThemidoscillationismostlikelydestabilizedbythecurrentdensitygradientThekineticeffectofthebarelytrappedsuprathermale

6、lectronsisalsoinvestigatedtheoretically，andthiseffectmaybeneglectedformidoscillationexcitationItisproposedthatthestabilizationofthem=lmodebeforethesubsequentsawtoothcrashmightresultfromtheflatteningofthecurrentprofilebec

7、auseofthelocallyenhancedtransportofthesuprathermalelectronsduetothem21magneticislandThismodelcanexplainthemaincharacteristicsofthesawtoothactivityandthemid—oscillationsobservedinvariousexperimentalconditionsInaddition，in

8、ordertoobtainthecurrentprofile，whichisaccurateenoughforquantitativelyinvestigationofthemechanismoftheMHDinstabilitiesonEASTinthefuture，anequilibriumreconstructioncode，usingEFITmethod，writteninmixedlanguagesofFortranandMa