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Heat and Mass Transfer

, Volume 44, Issue 8, pp 959–967 | Cite as

Numerical study of heat transfer enhancement of finned flat tube bank fin with vortex generators mounted on both surfaces of the fin

  • Ke-Wei Song
  • Liang-Bi Wang
  • Ju-Fang Fan
  • Yong-Heng Zhang
  • Song Liu
Original

Abstract

Tube bank fin heat exchanger is one of the most compact heat exchangers, and it is widely used in industry equipments. The flat tube bank fin heat exchangers with vortex generators (VGs) have significant good heat transfer performance, and are used as radiators of locomotive. Here, we study heat transfer enhancement of a new fin where VGs are mounted on both surfaces of the fin. The heat transfer performance of this pattern is evaluated by a numerical method, and the results are compared with those obtained, under identical mass flow rate, when the VGs are mounted only on one surface of the fin. The results reveal that using this new pattern the height of VGs can be reduced and still obtain satisfactory heat transfer enhancement, while the pressure drop is reduced. The results also reveal that if VGs on one surface of the fin is determined, the locations where VGs are mounted on other surface of the same fin are very important, with configurations studied in this paper, depending on the value of Reynolds number, there exists an optimum location with which best heat transfer performance can be obtained.

Keywords

Heat Transfer Heat Transfer Coefficient Heat Transfer Enhancement Vortex Generator Heat Transfer Performance 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

List of symbols

a

width of flat tube

b

length of flat tube

c

span distance between two VGs around tube

cp

specific heat capacity

dh

hydraulic diameter

dx

the relative distance of VG on fin surface I to VG on fin surface II

f

friction factor: = Δpd h/(x Lρu 2 m/2)

h

heat transfer coefficient

H

height of winglet type vortex generators

L

base length of vortex generator

Nu

Nusselt number: Nu hd h

p

pressure

Re

Reynolds number: Re = ρu m d h

S1

transversal pitch between flat tubes

S2

longitudinal pitch between flat tubes

Tp

fin spacing

T

temperature

um

maximum average velocity of air

u,v,w

components of velocity vector

x,y,z

coordinates

xL

stream wise length of fin

Greek symbols

λ

heat conductivity

μ

viscosity

ρ

density

θ

attack angle of vortex generator

Θ

dimensionless temperature

Δp

pressure drop

Subscripts

local

local value

m

average

w

wall or fin surface

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Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  • Ke-Wei Song
    • 1
  • Liang-Bi Wang
    • 1
  • Ju-Fang Fan
    • 1
  • Yong-Heng Zhang
    • 1
  • Song Liu
    • 1
  1. 1.Department of Mechanical EngineeringLanzhou Jiaotong UniversityLanzhouPeople’s Republic of China

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