粘弹性流体绕圆柱流动的数值模拟

摘要Ⅰ摘要Ⅰ摘要当流体流过相对静态的钝性结构或物体时，钝性的物体或主体将承受由于流体和涡流的分离而产生的连续脉动流动力的作用。因此，该结构必须足够坚固以承受冲击。钝体绕流的工程应用非常多样，例如飞机机翼之间的立柱，潜水器的通风管，高压管线，发电厂的冷却塔，桥梁，高层建筑，热交换器的管。热量和更多。在生产的实际生活中，普遍存在的普遍问题是需要尽可能降低流体的阻力。因此，长期以来一直寻求在涉及粘性流体运动的所有区域中减小从水下运动物体到航天飞机的流体阻力。本文使用Fluent软件的RNGk-e模型对具有亚临界雷诺数的粘弹性流体的圆柱和方柱周围的旋转问题进行了数值研究。通常，Re数越高，方柱的电阻越大，而圆柱体则不是这种情况。Re越高，两个气缸的升程越高。对于圆柱体，在相同条件下，方柱的阻力更大；相反，方柱涡旋频率较低。Re越高，串联的气缸的Sr值与单个气缸的Sr值越接近。关键词：圆柱绕流；升力系数；阻力系数；斯特劳哈尔数AbstractⅡAbstractⅢTitle NumericalsimulationofflowaroundacylinderofviscoelasticfluidAbstractWhenthefluidflowsthrougharelativelystaticstructureorbluntbody,thestructureorbluntbodywillbesubjectedtocontinuousandpulsatingflowforceduetofluidseparationandvortexshedding.Sothestructuremustbestrongenoughtowithstandtheimpact.Theengineeringapplicationofbluntbodyflowaroundisveryextensive,suchasaircraftwingpillar,snorkellingpipeofsubmersibleboat,highvoltagetransmissionline,coolingtowerinpowerplant,bridge,high-risebuilding,pipeinheatexchangerandsoon.However,thecommonprobleminreallifeistoreducethefluidresistanceasmuchaspossible.Therefore,foralongtime,peoplehavebeenlookingforwaystoreducefluidresistanceinareasinvolvingviscousfluidmotion,fromunderwaterobjectstoaerospacevehicles.Inthispaper,RNGK-modelinFluentsoftwarewasusedtonumericallystudytheflowaroundacylinderandasquarecylinderofviscoelasticfluidunderasubcriticalReynoldsnumber.Bycomparingtheresults,theeffectsofReynoldsnumberandcylindershapeontheflowaroundthecylinder,liftandvortexfrequencywereanalyzed.Generallyspeaking,thegreatertheRenumberis,thegreatertheresistanceofthesquarecolumnwillbe,butnotthecylinder.ThelargerReis,thelargertheliftforceofbothcylindersis.Comparedwiththecylinder,theresistanceofthesquarecolumnisgreaterunderthesamecondition.Onthecontrary,thevortexsheddingfrequencyofsquarecolumnissmaller.ThelargerReis,themoretheSrnumberofacolumninaseriesisclosetothatofasinglecylinder.Keywords:Cylinderflowaround;Liftcoefficient;Resistancecoefficient;Strouhal'snumber目录 目录 TOC\o"1-3"\h\u20310第1章绪论 -结论本文使用商业软件Fluent，使用RNGk-e模型对具有亚临界雷诺数的圆柱和方柱中粘弹性流体流动的轮廓问题进行了数值研究。首先，验证所用网格的独立性，然后计算出具有不同间距的串联气缸的Sr数量，并将其与文献中的数据进行比较，从而验证该方法和应用的准确性。从程序。然后，文章分析了雷诺数和圆柱体形状对圆柱体绕流阻力，涡旋高