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Numerical simulation on drag reduction of revolution body through bionic riblet surface

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Science China(Technological Sciences) 2010年第11期53卷 2954-2959页

作者： ZHANG ChengChun WANG Jing SHANG YanGeng Key Laboratory of Bionics Engineering Ministry of EducationJilin UniversityChangchun 130022China College of Agriculture Department of PhysicsJilin UniversityChangchun 130062China

Numerical simulations of flow fields on the bionic riblet and the smooth revolution bodies were performed based on the SST k-ω turbulence model in order to explain the mechanisms of the skin friction drag reduction, base drag reduction on the riblet surface, and flow control behaviors of riblet surface near the wall. The simulation results show that the riblet surface arranged on the rearward of the revolution body can reduce the skin friction drag by 8.27%, the base drag by 9.91% and the total drag by 8.59% at Ma number 0.8. The riblet surface reduces the skin friction drag by reducing the velocity gradient and turbulent intensity, and reduces the base drag by weakening the pumping action on the dead water region which behind the body of revolution caused by the external flow. The flow control behavior on boundary layer shows that the riblet surface can cut the low-speed flow near the wall effectively, and restrain the low-speed flow concentrating in span direction, thus weaken the instability of the low speed steaks produced by turbulent flow bursting.

关键词： bionic engineering riblet surface drag reduction numerical simulation revolution body

Drag Reducing and Increasing Mechanism on Triangular riblet surface

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Transactions of Nanjing University of Aeronautics and Astronautics 2014年第1期31卷 78-84页

作者：封贝贝陈大融汪家道杨星团 Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education Institute of Nuclear and New Energy TechnologyTsinghua University The State Key Laboratory of Tribology Tsinghua University

Drag reducing and increasing mechanism on riblet surface has been studied through computational fluid dynamics(CFD).Drag reduction is achieved through the optimization of riblet geometry which would affect flow structure inside riblet *** and flow structure on riblet surface are analyzed and compared with those of smooth surface based on the k-εturbulence *** reducing and increasing mechanism is proved to be related to microvortexes induced inside riblets which lead to Reynolds shear stress reduction significantly and is considered to be the dominant factor resulting in wall friction *** results also show that the pressure drag generating from the deviation of static pressure on the front and rear ends of riblets occurs and grows exponentially with Mach number,which can cause drag ***,near-wall vortical structures,Reynolds shear stress and static pressure on riblet surfaces are also analyzed in detail.

关键词： riblet surface k-ε turbulence model drag reduction

A method for testing drag-reduction on riblet surfaces based on the Spalding formula

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Journal of Marine Science and Application 2009年第4期8卷 333-337页

作者：宋保维刘占一许婷胡海豹黄明明西北工业大学航海学院陕西省西安市710072

This paper presents a method based on riblet surfaces. Its advantage lies in that it is more with testing methods using instruments such as a the Spalding formula for testing drag-reduction on convenient and yields more precise data compared scale. With this method, data is obtained from the velocity distribution within the inner layer, nearest the riblet surface. Precision of measurement of the velocity distribution is the key factor affecting the precision of the testing.

关键词： Spalding formula riblet surface drag-reduction testing