EN ISO 12567-1:2000
(Main)Thermal performance of windows and doors - Determination of thermal transmittance by hot box method - Part 1: Complete windows and doors (ISO 12567-1:2000)
Thermal performance of windows and doors - Determination of thermal transmittance by hot box method - Part 1: Complete windows and doors (ISO 12567-1:2000)
This European Standard specifies a method based on ISO 8990 to measure the overall thermal transmittance (U-value) of a window or door in a hot box. This includes all effects of frames, sashes, door leaves and fittings in a test specimen.
Wärmetechnisches Verhalten von Fenstern und Türen -Bestimmung des Wärmedurchgangskoeffizienten mittels des Heizkastenverfahrens - Teil 1: Komplette Fenster und Türen (ISO 12567-1:2000)
Diese Norm legt ein Verfahren zur Messung des Wärmedurchgangskoeffizienten einer Tür oder eines Fenstersystems fest. Sie erfaßt alle Einflüsse von Rahmen, Schiebeflügeln, Abschlüssen, Türblättern und Befestigungßubehörteilen.
Isolation thermique des fenêtres et portes - Détermination de la transmission thermique par la méthode à la boîte chaude -Partie 1: Fenêtres et portes complètes (ISO 12567-1:2000)
La présente norme européenne décrit une méthode basée sur l'ISO 8990 pour mesurer le coefficient de transmission thermique global (coefficient U) d'une fenêtre ou d'une porte dans une boîte chaude. Ceci comprend tous les effets des menuiseries fixes et mobiles, des vantaux et des accessoires d'une éprouvette d'essai.
Toplotne lastnosti oken in vrat - Ugotavljanje toplotne prehodnosti z metodo komorne naprave - 1. del: Celotna okna in vrata (ISO 12567-1:2000)
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 12567-1:2001
01-september-2001
Toplotne lastnosti oken in vrat - Ugotavljanje toplotne prehodnosti z metodo
komorne naprave - 1. del: Celotna okna in vrata (ISO 12567-1:2000)
Thermal performance of windows and doors - Determination of thermal transmittance by
hot box method - Part 1: Complete windows and doors (ISO 12567-1:2000)
Wärmetechnisches Verhalten von Fenstern und Türen -Bestimmung des
Wärmedurchgangskoeffizienten mittels des Heizkastenverfahrens - Teil 1: Komplette
Fenster und Türen (ISO 12567-1:2000)
Isolation thermique des fenetres et portes - Détermination de la transmission thermique
par la méthode a la boîte chaude -Partie 1: Fenetres et portes completes (ISO 12567-
1:2000)
Ta slovenski standard je istoveten z: EN ISO 12567-1:2000
ICS:
91.060.50 Vrata in okna Doors and windows
91.120.10 Toplotna izolacija stavb Thermal insulation
SIST EN ISO 12567-1:2001 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN ISO 12567-1:2001
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SIST EN ISO 12567-1:2001
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SIST EN ISO 12567-1:2001
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SIST EN ISO 12567-1:2001
INTERNATIONAL ISO
STANDARD 12567-1
First edition
2000-09-01
Thermal performance of windows and
doors — Determination of thermal
transmittance by hot box method —
Part 1:
Complete windows and doors
Isolation thermique des fenêtres et portes — Détermination de la
transmission thermique par la méthode à la boîte chaude —
Partie 1 : Fenêtres et portes complètes
Reference number
ISO 12567-1:2000(E)
©
ISO 2000
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SIST EN ISO 12567-1:2001
ISO 12567-1:2000(E)
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ii © ISO 2000 – All rights reserved
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SIST EN ISO 12567-1:2001
ISO 12567-1:2000(E)
Contents Page
Foreword.iv
Introduction.v
1 Scope .1
2 Normative references .1
3 Terms, definitions and symbols.2
4 Principle.3
5 Requirements for test specimens and apparatus .7
6 Test procedure.11
7 Test report .15
Annex A (normative) Environmental temperatures.17
Annex B (normative) Linear thermal transmittance of the edge zone.21
Annex C (informative) Design of calibration transfer standard (CTS).24
Annex D (informative) Example of calibration test and measurement of window specimen.28
Annex E (informative) Analytical calibration procedure using heat balance equations.39
Bibliography.41
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SIST EN ISO 12567-1:2001
ISO 12567-1:2000(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO
member bodies). The work of preparing International Standards is normally carried out through ISO technical
committees. Each member body interested in a subject for which a technical committee has been established has
the right to be represented on that committee. International organizations, governmental and non-governmental, in
liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical
Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3.
Draft International Standards adopted by the technical committees are circulated to the member bodies for voting.
Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this International Standard may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights.
International Standard ISO 12567-1 was prepared by Technical Committee ISO/TC 163, Thermal insulation,
Subcommittee SC 1, Test and measurement methods.
ISO 12567 consists of the following parts, under the general title Thermal performance of windows and doors —
Determination of thermal transmittance by hot box method:
� Part 1: Complete windows and doors
� Part 2: Roof windows and other projecting windows
Annexes A and B are a normative part of this International Standard. Annexes C, D and E are for information only.
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SIST EN ISO 12567-1:2001
ISO 12567-1:2000(E)
Introduction
The method specified in this part of ISO 12567 is based on ISO 8990. It is designed to provide both standardized
tests, which enable a fair comparison of different products to be made, and specific tests on products for practical
application purposes. The former specifies standardized specimen sizes and applied test criteria.
The determination of the aggregate thermal transmittance is performed for conditions which are similar to the actual
situation of the window and door in practice.
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SIST EN ISO 12567-1:2001
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SIST EN ISO 12567-1:2001
INTERNATIONAL STANDARD ISO 12567-1:2000(E)
Thermal performance of windows and doors — Determination of
thermal transmittance by hot box method —
Part 1:
Complete windows and doors
1 Scope
This part of ISO 12567 specifies a method to measure the thermal transmittance of a door or window system. This
includes all effects of frames, sashes, shutters, door leaves and fittings.
It does not include:
� edge effects occurring outside the perimeter of the specimen;
� energy transfer due to solar radiation on the specimen;
� effects of air leakage through the specimen;
� roof windows and projecting products, where the glass layer projects beyond the cold side roof surface.
NOTE For roof windows and projecting units, the procedure given in ISO 12567-2 (under preparation, see Bibliography [4])
should be used.
Annex A gives methods for the calculation of environmental temperatures.
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of
this part of ISO 12567. For dated references, subsequent amendments to, or revisions of, any of these publications
do not apply. However, parties to agreements based on this part of ISO 12567 are encouraged to investigate the
possibility of applying the most recent editions of the normative documents indicated below. For undated
references, the latest edition of the normative document referred to applies. Members of ISO and IEC maintain
registers of currently valid International Standards.
ISO 7345, Thermal insulation — Physical quantities and definitions.
ISO 8301, Thermal insulation — Determination of steady-state thermal resistance and related properties — Heat
flow meter apparatus.
ISO 8302, Thermal insulation — Determination of steady-state thermal resistance and related properties —
Guarded hot plate apparatus.
ISO 8990:1994, Thermal insulation — Determination of steady-state thermal transmission properties — Calibrated
and guarded hot box.
ISO 9288, Thermal insulation — Heat transfer by radiation — Physical quantities and definitions.
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SIST EN ISO 12567-1:2001
ISO 12567-1:2000(E)
IEC 60584-1, Thermocouples — Part 1: Reference tables.
EN 12898, Glass in building — Determination of the emissivity.
3 Terms, definitions and symbols
3.1 Terms and definitions
For the purposes of this part of ISO 12567 the terms and definitions given in ISO 7345, ISO 8990 and ISO 9288
apply.
3.2 Symbols
For the purposes of this part of ISO 12567 the quantities given in ISO 7345 and ISO 9288 apply, together with
those given in Tables 1 and 2.
Table 1 — Symbols and units
Symbol Physical quantity Unit
2
A area
m
d thickness (depth) m
F fraction —
f view factor —
2
h surface coefficient of heat transfer
W/(m �K)
H
height m
L perimeter length m
2
q density of heat flow rate
W/m
2
R thermal resistance
m �K/W
T thermodynamic temperature K
2
U thermal transmittance
W/(m �K)
w width m
� radiant factor —
�T, �� temperature difference K
total hemispherical emissivity —
�
Celsius temperature
� �C
� thermal conductivity W/(m�K)
2 4
Stefan-Boltzmann constant
� W/(m �K )
heat flow rate W
�
� linear thermal transmittance
W/(m�K)
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SIST EN ISO 12567-1:2001
ISO 12567-1:2000(E)
Table 2 — Subscripts
Subscript Significance
b baffle
c convection (air)
cal calibration
e external, usually cold side
i internal, usually warm side
in input
m measured
me mean
n environmental (ambient)
ne environmental (ambient) external
ni environmental (ambient) internal
p reveal of surround panel
r radiation (mean)
ssurface
sp specimen
st standardized
sur surround panel
ttotal
4Principle
The thermal transmittance, U, of the specimen is measured by means of the calibrated or guarded hot box method
in accordance with ISO 8990.
The determination of the thermal transmittance involves two stages. First, measurements are made on two or more
calibration panels with accurately known thermal properties, from which the surface coefficient of the heat transfer
(radiative and convective components) on both sides of the calibration panel and the thermal resistance of the
surround panel are determined. Secondly, measurements are made with the window or door specimens in the
aperture and the hot box apparatus is used with the same fan settings on the cold side as during the calibration
procedure.
The surround panel is used to keep the specimen in a given position. It is constructed with outer dimensions of
appropriate size for the apparatus, having an aperture to accommodate the specimen (see Figures 1 and 2).
The principal heat flows through the surround panel and the calibration panel (or test specimen) are shown in
Figure 3. The boundary edge heat flow due to the location of the calibration panel in the surround panel is
determined separately by a linear thermal transmittance,� .
The procedure in this part of ISO 12567 includes a correction for the boundary edge heat flow, so that standardized
and reproducible thermal transmittance properties are obtained.
The magnitude of the boundary edge heat flow as a function of geometry, calibration panel thickness and thermal
conductivity is determined by tabulated values given in annex B.
Measurement results are corrected to standardized surface heat transfer coefficients by an interpolation or
analytical iteration procedure, derived from the calibration measurements.
Measures are taken (e.g. pressure equalization between the warm and cold side or sealing of the joints on the
inside) to ensure that the air permeability of the test specimen does not influence the measurements.
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SIST EN ISO 12567-1:2001
ISO 12567-1:2000(E)
Dimensions in millimetres
The total gap width between the top and bottom of the specimen and the surround panel aperture shall not exceed
5 mm. It shall be sealed with non-metallic tape or mastic material. The total gap width on both sides between the
specimen and the surround panel aperture shall not exceed 5 mm.
Key
a
1 Border of metering area
Recommended to be centrally located.
2 Surround panel, �u 0,04 W/(m�K)
b
Use fill material with same thermal properties as surround
panel core.
3Glazing
4Coldside
5Warmside
6 Flush sill
Figure 1 — Window system in surround panel
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SIST EN ISO 12567-1:2001
ISO 12567-1:2000(E)
Dimensions in millimetres
The total gap width between the top and bottom of the specimen and the surround panel aperture shall not exceed
5 mm. It shall be sealed with non-metallic tape or mastic material. The total gap width on both sides between the
specimen and the surround panel aperture shall not exceed 5 mm.
Key
a
1 Border of metering area
Recommended to be centrally located.
2 Surround panel, �u 0,04 W/(m�K)
b
Use fill material with same thermal properties as surround
panel core.
3 Infill (glass, panel)
4Coldside
5Warmside
6 Door leaf
7 Flush frame/threshold
Figure 2 — Door system in surround panel
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SIST EN ISO 12567-1:2001
ISO 12567-1:2000(E)
Key
1 Surround panel
2 Boundary effect
3Coldside
4Warmside
5 Calibration panel
Figure 3 — Mounting of calibration panel in aperture
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SIST EN ISO 12567-1:2001
ISO 12567-1:2000(E)
5 Requirements for test specimens and apparatus
5.1 General
The construction and operation of the apparatus shall comply with the requirements specified in ISO 8990, except
where modified by this part of ISO 12567. To make heat transfer measurements on the specimen, it is necessary to
mount it in a suitable surround panel and deduce the heat flow through it by subtracting that through the surround
panel from the total heat input. Also, the test element and the surround panel will usually be of different thickness,
so that there will be disturbance of heat flow paths and temperatures in the region of the boundary between the
two. The test shall be carried out so that edge corrections can be applied.
5.2 Surround panels
The surround panel acts as an idealized wall with high thermal resistance and holds the window or door in the
correct position and separates the warm box from the cold box. The surround panel shall be large enough to cover
the open face of the guard box in the case of a guarded hot box apparatus, or the open face of the hot box in the
case of a calibrated hot box apparatus.
The surround panel shall be not less than 100 mm thick or the maximum thickness of the specimen, whichever is
the greater, and it shall be constructed with core material of stable thermal conductivity not greater than
0,04 W/(m�K). An appropriate aperture shall be provided to accommodate the calibration panel or test specimen
(see Figures 1, 2, 3 and 4). Sealed plywood facing or plastic sheet on either side of the surround panel to provide
rigidity is permitted. No material of thermal conductivity higher than 0,04 W/(m�K) (other than non-metallic thin tape)
shall bridge the aperture. The surfaces of the surround panel and baffle plates shall have a high emissivity (> 0,8).
5.3 Test specimens
For general applications, specimen sizes may be typical of those found in practice. To ensure consistency of
measurement, the specimen should be located as follows. The window or door system shall fill the surround panel
aperture. The internal frame face shall be as close to the face of the surround panel as possible, but no part shall
project beyond the surround panel faces on either the cold or warm sides, except for handles, rails or fittings which
normally project (see Figures 1 and 2).
It is recommended that the aperture should be placed centrally into the surround panel and at least 200 mm from
the inside surfaces of the cold and hot boxes to avoid or limit edge heat flow corrections related to the perimeter of
thesurroundpanel.
For standardized test applications, the overall sizes recommended are indicated in Table 3, or they shall conform
with the size required by national standards or other regulations.
2
In any case the area of aperture shall be not less than 0,8 m , for reasons of accuracy. The perimeter joints
between the surround panel and the specimen shall be sealed on both sides with tape, caulking or mastic material.
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SIST EN ISO 12567-1:2001
ISO 12567-1:2000(E)
Dimensions in millimetres
Key
1 Surround panel
2 Test specimen
Figure 4 — Surround panel with test specimen
Table 3 — Specimen sizes
Component Height Width
mm mm
a a
Window
1480 1230
Door (leaf or doorset) 2000 1000
a
Standardized specimen size for sound insulation
measurements (ISO 140-1 and ISO 140-3).
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SIST EN ISO 12567-1:2001
ISO 12567-1:2000(E)
5.4 Calibration panels
Calibration panels shall be of a size similar to the test specimen (within � 40 % in height and width). They are
required to set up specified test conditions, to determine the surface coefficients of heat transfer and to establish
the thermal resistance of the surround panel.
At least two calibration panels shall be built which fulfil the following requirements.
a) The core material of the calibration panel shall be made of homogeneous material with known thermal
conductivity or thermal resistance. The material used shall not be prone to ageing effects.
b) The nature of the surface of the calibration panel shall be similar to that of the test specimen. The emissivity of
the surface shall be known (e.g. normal float glass) or shall be measured according to EN 12898.
c) The calibration panels shall cover the likely range of test specimen density of heat flow rate. The use of two
calibration panels with different total thickness is recommended:
1) total thickness approximately 20 mm;
2) total thickness approximately 60 mm.
More details and guidance on how to build up the calibration panels are given in annex C.
The thermal resistance of the insulating material used in the panels shall be measured for mean temperatures in
the range 0 �Cto15 �C by using a guarded hot plate or heat flow meter apparatus in accordance with ISO 8302 or
ISO 8301 respectively. Alternatively calibration panels may be used with certified properties from an accredited
source. In any case the calibration panels shall be mounted in the surround panel aperture 40 mm from the warm
face as shown in Figure 3.
5.5 Temperature measurements and baffle positions
For calibration measurements, the warm and cold side surface temperatures shall be measured or calculated. (For
calibration panel design and sensor mounting, see annex C.) A minimum of 9 positions at the centre of a
rectangular grid of equal areas shall be used on the calibration panel and 8 positions on the surround panel
(Figure 5). No temperature sensors shall be closer than 100 mm to the edge of the calibration panel. Temperature
sensors and recording systems shall be accurately calibrated. The recommended temperature sensor to be used
for surface temperature measurement is the type T thermocouple (copper/constantan) according to IEC 60584-1
made from wire with diameter not greater than 0,5 mm. They shall be fixed to the surface using adhesive or
adhesive tape with an outer surface of high emissivity (> 0,8). If alternative sensors are used, they shall be at least
as accurate as the above, not subject to drift or hysteresis, and shall be as small as possible to avoid disturbance
of the temperature field near the point of contact. Suitability can be investigated with an infrared camera under heat
flow conditions similar to the required operating specifications.
It is recommended that the same layout of the surface temperature grid on the calibration panel is used
(a minimum of 9) for air temperature and baffle plate measurements.
For natural convection on the warm side, the distance between the baffle and the plane of the warm face of the
surround panel shall be not less than 150 mm and on the cold face not less than 50 mm for appropriate air speed
(not less than 1,5 m/s during the first calibration test, see 5.6 and 6.2.2.1). Air temperatures shall be measured on
each side outside the boundary layer.
5.6 Air flow measurement
The cold side air speed shall be measured at a position that represents the free stream condition. For either vertical
or horizontal flow patterns, it is essential that the sensor is not in the test specimen surface boundary layers or in
the wake of any projecting fitting. If a small fan is used on the warm side, an air speed sensor (see Figure 5) shall
be used to verify that the air speed representing natural convection prevails (less than 0,3 m/s).
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SIST EN ISO 12567-1:2001
ISO 12567-1:2000(E)
Dimensions in millimetres
Key
1 Cold-side baffle
2 Warm-side baffle
X Temperature sensors
a
It is recommended that air-speed sensors be aligned in the centre for parallel flow.
b
All surround panel thermocouples should be located centrally.
Figure 5 — Location of temperature and air speed sensors
If the dimensions of the metering box are such that its perimeter contacts lie closer to the aperture edges than
200 mm, then it is inappropriate to measure the warm surface temperatures of the surround panel. In this instance,
it is permissible to use warm side average air temperatures as replacement for surround panel average warm
surface temperature to determine �� in the calibrations in 6.2.4 [equation (8)]. If this is done, then the same
s,sur
procedure shall be adopted to correct for the surround panel influences in the subsequent measurements [see 6.3,
equation (12)].
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SIST EN ISO 12567-1:2001
ISO 12567-1:2000(E)
6 Test procedure
6.1 General
The general operating procedure for the hot box measurements shall follow that specified in ISO 8990, and in
addition, the following requirements shall be complied with.
6.2 Calibration measurements
6.2.1 General
These are required to ensure that suitable test conditions are set up and that the surround panel heat flow and
surface heat transfer coefficients can be fully accounted for.
The calibration measurements shall be carried out at a minimum of six densities of heat flow rates which cover the
required range of specimen testing.
It is recommended to make the calibration measurements at three different mean air temperatures
� [� =(� +� )/2] in steps of � 5 K by varying the cold side air temperature, retaining constant
c,me c,me c,i c,e
conditions of air movement on the cold side and constant air temperature and natural convection on the warm side.
By this procedure surface resistances and coefficients of heat transfer can be determined as a function of the total
density of heat flow rate through the calibration panel.
NOTE It is considered that for non-homogeneous test specimens like windows or doors, the mean heat transfer conditions
over the measured area will be comparable to those of the given calibration panel.
6.2.2 Total surface resistance
6.2.2.1 Measurement
The first calibration test shall be made with the thin panel (d � 20 mm) at a mean temperature of approximately
cal
10 �C or appropriate to national standards and a temperature difference, �� between warm and cold sides, of
c
(20 � 2) K or appropriate to national standards (see ISO 8990 and annex A for the determination of the environ-
mental temperatures).
The air velocity on the cold side shall be adjusted for the first calibration test by throttling or by fan speed
2
adjustment to give a total surface thermal resistance (warm and cold side) R =(R � 0,01) m �K/W, e.g.
s,t (s,t),st
2
(0,17 � 0,01) m �K /W or appropriate to national standards. Thereafter the fan speed settings and/or the throttling
devices shall remain constant for all subsequent calibration measurements. The setup used for the calibration
procedure shall be used for all tests with specimens of windows or doors.
6.2.2.2 Calculation
2
Calculate the total surface thermal resistance of the warm and cold side, R , expressed in m �K/W, using
s, t
equation (1):
�����
n,cal s,cal
R � (1)
s,t
q
cal
where
�� is the difference between environmental temperatures on each side of the calibration panel, in kelvin,
n,cal
calculated according to annex A;
�� is the surface temperature difference of the calibration panel, in kelvin;
s,cal
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SIST EN ISO 12567-1:2001
ISO 12567-1:2000(E)
q is the density of heat flow rate of the calibration panel determined from the known thermal resistance,
cal
R , of the calibration panel (at the mean temperature, � ) and the surface temperature difference,
cal cal
�� , calculated using equation (2):
s,cal
��
s,cal
q � (2)
cal
R
cal
where R is the thermal resistance of the calibration panel at the mean temperature of the panel, calculated
cal
using equation (3):
d
j
R � (3)
cal �
�
j
where
d is the thickness of layer j,inmetres;
j
� is the thermal conductivity of layer j,inW/(m�K).
j
The total surface resistance, R , shall be plotted as a function of the density of heat flow rate, q ,of
s,t
cal
the calibration panel. These characteristics are used to determine the total surface resistances of all subsequent
measurements of test specimens (windows and doors).
6.2.3 Surface resistances and surface coefficients of heat transfer
6.2.3.1 General
Surface coefficients of heat transfer (convective and radiative parts) are needed in order to determine the
environmental temperatures (according to the procedures given in annex A and ISO 8990). Surface temperature
measurements on the calibration panel at different densities of heat flow rate will allow the determination of the
surface coefficients of heat transfer. The surface resistances are calculated using equations (4) and (5):
���
ni,cal si,cal
R � (4)
si
q
cal
���
se,cal ne,cal
R � (5)
se
q
cal
where
2
q is the density of heat flow rate through the calibration panel, in W/m ;
cal
� is the environmental temperature of the warm side, in degrees Celsius;
ni,cal
� is the warm side surface temperature of the calibration panel, in degrees Celsius;
si,cal
� is the cold side surface temperature of the calibration panel, in degrees Celsius;
se,cal
� is the environmental temperature of the cold side, in degrees Celsius.
ne,cal
6.2.3.2 Convective fraction
Evaluate the radiative and convective parts of the surface coefficients of heat transfer from the calibration data for
the warm and cold side according to the procedure given in annex A and determine the convective fraction, F ,
c
using the equation (6):
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SIST EN ISO 12567-1:2001
ISO 12567-1:2000(E)
h
c
F � (6)
c
hh�
cr
where
2
h is the convective coefficient of heat transfer, in W/(m �K);
c
2
h is the radiative coefficient of heat transfer, in W/(m �K).
r
The variation of the convective fraction, F , shall be plotted for both sides as a function of q (density of heat flow
cal
c
rate of the calibration panel). It will be used
...
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