Heat Transfer Enhancement in a Heat Exchanger Tube with 45° Rectangular-Winglet Pairs

9th Thai Society of Mechanical Engineers, International Conference on Mechanical Engineering

Tongyote, P.^1 ; Sripattanapipat, S.^2 ; Promvonge, P.^1

Department of Mechanical Engineering, Faculty of Engineering, King Mongkut's Institute of Technology, Ladkrabang Bangkok

10520, Thailand^1

Department of Mechanical Engineering, Faculty of Engineering, Mahanakorn University of Technology, Bangkok

10530, Thailand^2

关键词: Experimental investigations;    Heat Transfer enhancement;    Operating condition;    Pressure loss;    Rectangular winglets;    Thermal characteristics;    Thermal enhancement;    Thermal Performance;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/501/1/012060/pdf
DOI  :  10.1088/1757-899X/501/1/012060

来源: IOP

【 摘 要 】

An experimental investigation on thermal characteristics in a heat exchanger equipped with 45° rectangular winglet pairs (RWP) is conducted using air flowing in a constant heat flux tube with Reynolds number (Re) in a range of 5,200 to 23,000. Parameters of RWP included three relative height or blockage ratios (BR = 0.06, 0.08 and 0.1) and two pitch-spacing ratios (PR = 1.0 and 2.0). The heat transfer and the pressure drop in the test tube are displayed in the form of Nusselt number (Nu) and friction factor (f), respectively. The investigation shows that Nu and f values of the tube with RWP insert are, respectively, in the range of about 1.55-3.2 and 3.76-6.44 times above the plain tube alone, depending on the operating condition. The maximum thermal performance for using the RWP is found to be 1.7 at the lowest Re.