Heat and Mass Transfer

, Volume 43, Issue 12, pp 1273–1281 | Cite as

Flow and heat transfer analysis in porous wick of CPL evaporator based on field synergy principle

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Abstract

In order to optimize the structure of a CPL evaporator and enhance heat transfer, a mathematical and physical model is developed to analyze the flow and heat transfer in the porous wick of the evaporator, whose calculation domain is divided into two parts: vapor-saturated region and liquid-saturated region. The characteristics of flow and heat transfer in the porous wick of a CPL evaporator have been numerically studied according to the field synergy principle. The influences of geometrical structures and heat flux on heat transfer enhancement are analyzed and illustrated by the figures in the present paper.

Keywords

Heat Transfer Heat Flux Effective Thermal Conductivity Heat Transfer Enhancement Liquid Velocity 
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

c

specific heat (J kg−1 K−1)

hfg

latent heat of evaporation (J kg−1)

K

wick permeability (m2)

Lx

total wick length in x direction (m)

Lxf

heated wick length in x direction (m)

Ly

wick length in y direction (m)

p

pressure (Pa)

q

heat flux (W m−2)

Q

heat load (W)

Rg

gas constant (J kg−1 K−1)

r

effective capillary radius of wick pore (m)

t

time (s)

T

temperature (°C)

u

velocity in x direction (m s−1)

\({\vec{V}}\)

velocity vector (m s−1)

v

velocity in y direction (m s−1)

x, y

coordinates (m)

\({\vec{n}}\)

outward normal vector

Greek symbols

α

heat transfer coefficient (W m−2 K−1)

θ

synergy angle (°)

λ

thermal conductivity (W m−1 K−1)

φ

wetting angle (°)

μ

viscosity (Pa s)

ρ

density (kg m−3)

σ

liquid–vapor surface tension (N m−1)

ɛ

phase content

Subscripts

c

condenser

eff

effective

i

index to identify vapor or liquid

in

inlet

l

liquid

s

solid

sat

saturation

v

vapor

rf

reference

0

initial state

∞

vapor in groove

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Notes

Acknowledgments

This work is supported by the National Key Basic Research Development Program of China (no. 2007CB206901).

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Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  1. 1.School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhanPeople’s Republic of China
  2. 2.Department of Mechanical EngineeringShizuoka UniversityHamamatsuJapan

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