Heat and Mass Transfer

, Volume 50, Issue 7, pp 895–905 | Cite as

Thermographic validation of a novel, laminate body, analytical heat conduction model

  • Louis Desgrosseilliers
  • Dominic Groulx
  • Mary Anne White
Original

Abstract

The two-region fin model captures the heat spreading behaviour in multilayered composite bodies (i.e., laminates), heated only over a small part of their domains (finite heat source), where there is an inner layer that has a substantial capacity for heat conduction parallel to the heat exchange surface (convection cooling). This resulting heat conduction behaviour improves the overall heat transfer process when compared to heat conduction in homogeneous bodies. Long-term heat storage using supercooling salt hydrate phase change materials, stovetop cookware, and electronics cooling applications could all benefit from this kind of heat-spreading in laminates. Experiments using laminate films reclaimed from post-consumer Tetra Brik cartons were conducted with thin rectangular and circular heaters to confirm the laminate body, steady-state, heat conduction behaviour predicted by the two-region fin model. Medium to high accuracy experimental validation of the two-region fin model was achieved in Cartesian and cylindrical coordinates for forced external convection and natural convection, the latter for Cartesian only. These were conducted using constant heat flux finite heat source temperature profiles that were measured by infrared thermography. This validation is also deemed valid for constant temperature heat sources.

List of symbols

Dimensional variables

h

Convection heat transfer coefficient (W m−2 K−1)

k

Thermal conductivity (W m−1 K−1)

L

Heated boundary length and boundary-edge position from x, r = 0 (m)

Q

Total rate of heat transfer (W)

\(q_{o}^{\prime \prime }\)

Applied finite heat flux (W m−2)

r

Radial position (m)

R

Thermal resistance above the highly conductive metal core (m2 K W−1)

t

Layer thickness (m)

T

Temperature (K)

Ti

Applied temperature heat source (K)

Tinf

Free stream temperature (K)

To

Boundary temperature at x, r = L (K)

x

Cartesian axial position (m)

z

Vertical axis position (m)

Greek symbols

α

Heated region constant (m−1)

β

Heated region particular solution (K)

∆T

Temperature uncertainty 95 % confidence limit (K)

γ

Fin region constant (m−1)

Subscripts

1

High conductivity metal core

2

Top thermally resistive layer

3

Bottom thermally resistive layer

f

Fin region only

h

Heated region only

meas

Based on measurement data

model

Based on two-region fin model results

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Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  • Louis Desgrosseilliers
    • 1
    • 3
  • Dominic Groulx
    • 1
    • 3
  • Mary Anne White
    • 2
    • 3
  1. 1.Department of Mechanical EngineeringDalhousie UniversityHalifaxCanada
  2. 2.Department of ChemistryDalhousie UniversityHalifaxCanada
  3. 3.Institute for Research in MaterialsDalhousie UniversityHalifaxCanada

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