Experimental Study of Enhanced Heat Transfer in Ducts With Periodic Rectangular Fins Along the Main Flow Direction

Z.X. Yuan
School of Energy & Power Engineering Xi'an Jiaotong University Xi'an, Shaanxi, 710049 CHINA

Wuqiang Wang
School of Energy & Power Engineering, Xi'an Jiaotong University, 710049, Xi'an, China

Wen-Quan Tao
State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, China; Key Laboratory of Thermo-Fluid Science and Engineering of MOE, School of Energy and Power Engineering, Xian Jiaotong University, Xian 710049, China

Abstract

For the cooling of the trailing edge of turbine blade a periodically finned enhancement structure of rectangular plates is proposed to substitute the conventional pin fin structure. The experimental results of this new type of structure show that at the same Reynolds number, the Nusselt number of this kind of duct is about 1.25~2 times of the pin fin's in the range of Re = 5 × 10³ ~ 5 ~ 10⁴, and the friction factor of the former is appreciably lower than that of the latter. The Nusselt number ratio of the new type structure to that of a smooth duct, Nu/Nu₀, varies, from 3.7 to 8.7 at the same Reynolds number, while at the identical pumping power this ratio is about 2.4 ~ 4.7,