Transactions of the Korean Society of Mechanical Engineers B (대한기계학회논문집B)

The Korean Society of Mechanical Engineers (대한기계학회)
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The Effect of Wake-Induced Periodic Unsteadiness on Heat Transfer in the Transitional Boundary Layer Around NACA0012 Airfoil

주기적인 통과후류가 NACA0012 익형 표면에서의 천이 경계층 열전달에 미치는 영향

  • Published : 2001.05.01
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Abstract

Heat transfer data are presented which describe characteristics of the transitional thermal boundary layers on the NACA0012 airfoil with upstream wakes. The wakes are generated periodically by circular cylindrical rods which rotate around the airfoil like a squirrel cage. The unsteady wakes simulate those produced by the upstream rotating blade rows in axial turbomachines. The pressure or suction side of the airfoil is also simulated according to the rotating direction of circular rods. As the Reynolds number and the number of rotating rods increase, the boundary layer transition occurs earlier and the Nusselt number increases. The difference of heat transfer coefficient is less on the pressure side than on the suction side. At a constant Reynolds number, the Nusselt number is larger and smaller, respectively, before and after transition as the Strouhal number increases.

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References

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