仿生射流表面优化设计与减阻机理分析.pdf

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1、第45卷第5期中南大学学报(自然科学版)VbL45No．52014年5月JournalofCentralSouthUniversity(ScienceandTechnology)May2014仿生射流表面优化设计与减阻机理分析赵刚，李芳，杜军伟(哈尔滨工程大学机电工程学院，黑龙江哈尔滨，150001)摘要：针对不同射流表面参数减阻问题，建立仿生射流表面模型，利用SST∞湍流模型对其进行数值模拟，所得结果与实验数据吻合良好。运用正交试验设计法对影响射流表面摩擦阻力的因素进行分析，得到各因素对减阻效果和节能效果的影响规律：形状因子对减阻率和节能率的影响最大，流速比其次，流速比

2、与减阻率和节能率呈抛物线关系，形状因子与减阻率呈线性关系，且随着形状因子增大减阻率增大，最大减阻率为15．06％，最大节能率为13．57％。由于射流流体的阻碍作用，在射流孔背流面形成逆流区，逆流区近壁面形成的剪应力方向与来流方向相反，局部摩擦因数为负值，并且由于射流流体对主流场的推力作用，使得边界层黏性底层厚度增大，速度梯度减小，摩擦阻力减小。关键词：射流表面：减阻；数值模拟；正交试验设计；边界层中图分类号：TBI7文献标志码：A文章编号：1672-7207(2014)05-1449-08Optimizationdesignofbionicjetsurfaceandmec

3、hanismanalysisofdragreductionZHAOGang，LIFang，DUJunwei(CollegeofMechanicalandElectricalEngineering，HarbinEngineeringUniversity，Harbin150001，China)Abstract：Tosolvetheproblemofthedragreductionondifferentjetsurfaces，abionicsurfacewasbuilt．Thenumericalsimulationwascompletedbyusingtheturbulence

4、modelofshear-stresstransportSST∞．Theresultofthesimulationisinconformitywiththeresultoftheexperiment．Thefactorswhichaffecttheeffectofthedragreductiononthejetsurfacewereanalyzedbyusingtheorthogonalexperimenta1．Theresultsshowthattheeffectoftheshapefactoronthedragreductionrateandtheenergycons

5、ervationrateisthebestandtheefectofthevelocityratiofollows．Therelationshipsbetweenthevelocityratioandthedragreductionaswellastheenergyconservationarelikeaparabola．Therelationshipbetweentheshapefactorandthedragreductionrateislinear．Thedragreductionrateincreaseswiththeincreaseoftheshapefacto

6、r,thedragreductionratecanreachthemaximumof15．06％andtheenergyconservationCanreachthemaximum0f13．57％．Becausethefluidcomingfromthefetholehindersthefluidonthesurface，itwill1cadtoareverseflowregionontheleesideoftheiethole．Thedirectionoftheshearstressnearthewallofthereverseflowregioniscontraryt

7、othedirectionofthefluidonthesurface．Thetopicalfrictionfactorisnegative．Becausethefluidfromthejetholethrustthefluidonthesurface，thethicknessoftheviscoussublayeroftheboundarylayerincreases，thevelocitygradientdecreases，andthefrictionresistancedecreases．Keywords：jetsurf