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1、电弧喷涂过程的数值模拟摘要电弧喷涂是一种热喷涂技术。喷涂过程中熔滴颗粒的飞行速度和温度是影响喷涂涂层成形质量的重要因素。实验方法研究电弧喷涂过程存在着诸多困难,而数值模拟方法是当前此课题的重要研究手段。本研究基于双流体模型,并采用ANSYS/CFD多组分传输分析包分别对电弧喷涂时熔滴颖粒的空间飞行速度和温度分布的基本规律进行较为详细的分析:在此基础上再采用显式有限元分析软件LS_DYNA分析熔滴颗粒的沉积变形过程,沉积过程的分析全部采用ALE单元网格算法。通过改变电弧喷涂丝材材质和压缩空气的压力,本研究对比分析AI、Zn和不锈钢(1Cr18
2、Ni9Ti)三种不同丝材下熔滴行为的差异及压缩气流压力对熔滴飞行速度、空间温度分布及沉积变形过程的影响。数值模拟结果表明,喷涂同种丝材时,提高压缩空气压力有助于增大颗粒拟流体速度与温度的空间分布以及颗粒的沉积扁平度:双相流混合粘度}tmi:是影响不同丝材喷涂时空间速度分布差异的重要因素。此外还通过试验验证了飞行区温度分布模拟结果的可靠性。关键词:电弧喷涂,数值模拟,熔滴颗粒速度TheNumericalSimulationofArcSprayProcessAbstractThearcsprayisoneofthethermalspraytec
3、hnologies.Inthearcspray,thedropletvelocityandtemperatureareveryimportantforthecoatquality.Therearesomanydifficultieswhenusingphysicalexperiments,whilecurrentlyforthisproblemnumericalsimulationisanimportantmethod.Basedonthetwo-phaseflowmodelandbyusingtheANSYS/CFDmultiplespe
4、ciestransportprogram,thedropletvelocityandtemperatureinthearcspraywereinvestigateddetailed,andthenbyusingtheexplicitFEAsoftwareLS夕YNAweanalyzedthedropletflatteningafterimpactingontheflatsubstrate,andinalltheflatteningprocess,theALEmethodwasemployedalways.Byalteringthemater
5、ialandtheairpressure,thedifferencesofthedropletbehavioroftheAl,Znandstainlesssteel(1Crl8Ni9Ti)werediscussed,andtheeffectoftheairpressureonthedropletvelocity,temperatureandflatteningprocesswerealsoinvestigated.Thesimulationresultsindicated,forthesamematerial,thedropletveloc
6、ity,temperatureandthecompressedratewouldbeimprovedbyincreasingthepressure;andthetwo-phaseflowviscosityp.;,,wasanimportantfactorforthedropletvelocitydistribution.Thephysicalexperimentwasalsoemployedinthisarticletovalidatetheresultofthetemperaturesimulation.Keywords:arcspray
7、,numericalsimulation,dropletvelocity插图清单图1-1电弧喷涂工艺示意图········。········,,···············,················。······..·⋯.........3图2-1喷涂雾化示意图···‘··················,···························.....................7图2-2颗粒尾部的卡门涡旋·...................................................
8、.......................7图2-3Fluidl41单元构成图,...............................................