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ASTM C1043-97(2002)

(Practice)

Standard Practice for Guarded-Hot-Plate Design Using Circular Line-Heat Sources

Standard Practice for Guarded-Hot-Plate Design Using Circular Line-Heat Sources

SCOPE
1.1 This practice covers the design of a circular line-heat-source guarded hot plate for use in accordance with Test Method C 177.  
Note 1—Test Method C 177 describes the guarded-hot-plate apparatus and the application of such equipment for determining thermal transmission properties of flat-slab specimens. In principle, the test method includes apparatus designed with guarded hot plates having either distributed or line heat sources.  
1.2 The guarded hot plate with circular line-heat sources is a design in which the meter and guard plates are circular plates having a relatively small number of heaters, each embedded along a circular path at a fixed radius. In operation, the heat from each line-heat source flows radially into the plate and is transmitted axially through the test specimens.  
1.3 The meter and guard plates are fabricated from a continuous piece of thermally conductive material. The plates are made sufficiently thick that, for typical specimen thermal conductances, the radial and axial temperature variations in the guarded hot plate are quite small. By proper location of the line-heat source(s), the temperature at the edge of the meter plate can be made equal to the mean temperature of the meter plate, thus facilitating temperature measurements and thermal guarding.  
1.4 The line-heat source guarded hot plate has been used successfully over a mean temperature range from -10 to +65°C degrees C, with circular metal plates and a single line-heat source in the meter plate. The chronological development of the design of circular line-heat-source guarded hot plates is given in Refs (1-8).  
1.5 This practice does not preclude (1) lower or higher temperatures; (2) plate geometries other than circular; (3) line-heat-source geometries other than circular; (4) the use of plates fabricated from ceramics, composites, or other materials; or (5) the use of multiple line-heat sources in both the meter and guard plates.  
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

Status
Historical
Publication Date
09-Sep-1997
ICS
17.200.10 - Heat. Calorimetry
Technical Committee
C16 - Thermal Insulation
Drafting Committee
C16.30 - Thermal Measurement
Current Stage
Ref Project

Relations

Replaces
ASTM C1043-97 - Standard Practice for Guarded-Hot-Plate Design Using Circular Line-Heat Sources
Effective Date
10-Sep-1997
Replaced By
ASTM C1043-06 - Standard Practice for Guarded-Hot-Plate Design Using Circular Line-Heat Sources
Effective Date
01-Sep-2006
Referred By
ASTM C1114-06(2019) - Standard Test Method for Steady-State Thermal Transmission Properties by Means of the Thin-Heater Apparatus
Effective Date
10-Sep-1997
Referred By
ASTM C1045-19 - Standard Practice for Calculating Thermal Transmission Properties Under Steady-State Conditions
Effective Date
10-Sep-1997
Referred By
ASTM C177-19e1 - Standard Test Method for Steady-State Heat Flux Measurements and Thermal Transmission Properties by Means of the Guarded-Hot-Plate Apparatus
Effective Date
10-Sep-1997

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ASTM C1043-97(2002) - Standard Practice for Guarded-Hot-Plate Design Using Circular Line-Heat SourcesASTM C1043-97(2002) - Standard Practice for Guarded-Hot-Plate Design Using Circular Line-Heat Sources
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ASTM C1043-97(2002) - Standard Practice for Guarded-Hot-Plate Design Using Circular Line-Heat Sources
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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation:C1043–97 (Reapproved 2002)
Standard Practice for
Guarded-Hot-Plate Design Using Circular Line-Heat
1
Sources
This standard is issued under the fixed designation C1043; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope 1.6 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
1.1 This practice covers the design of a circular line-heat-
responsibility of the user of this standard to establish appro-
source guarded hot plate for use in accordance with Test
priate safety and health practices and determine the applica-
Method C177.
bility of regulatory limitations prior to use.
NOTE 1—Test Method C177 describes the guarded-hot-plate apparatus
and the application of such equipment for determining thermal transmis-
2. Referenced Documents
sion properties of flat-slab specimens. In principle, the test method
2.1 ASTM Standards:
includes apparatus designed with guarded hot plates having either
C168 Terminology Relating to Thermal Insulating Materi-
distributed- or line-heat sources.
3
als
1.2 The guarded hot plate with circular line-heat sources is
C177 Test Method for Steady-State Heat Flux Measure-
adesigninwhichthemeterandguardplatesarecircularplates
ments and Thermal Transmission Properties by Means of
having a relatively small number of heaters, each embedded
3
the Guarded-Hot-Plate Apparatus
along a circular path at a fixed radius. In operation, the heat
C1044 PracticeforUsingtheGuarded-Hot-PlateApparatus
from each line-heat source flows radially into the plate and is
intheOne-SidedModetoMeasureSteady-StateHeatFlux
transmitted axially through the test specimens.
3
and Thermal Transmission Properties
1.3 The meter and guard plates are fabricated from a
E230 Specification for Temperature-Electromotive Force
continuous piece of thermally conductive material. The plates
4
(EMF) Tables for Standardized Thermocouples
are made sufficiently thick that, for typical specimen thermal
2.2 ASTM Adjuncts:
conductances,theradialandaxialtemperaturevariationsinthe
5
Line-Heat-Source Guarded-Hot-Plate Apparatus
guarded hot plate are quite small. By proper location of the
line-heat source(s), the temperature at the edge of the meter
3. Terminology
plate can be made equal to the mean temperature of the meter
3.1 Definitions—For definitions of terms and symbols used
plate, thus facilitating temperature measurements and thermal
in this practice, refer to Terminology C168. For definitions of
guarding.
terms relating to the guarded-hot-plate apparatus refer to Test
1.4 The line-heat-source guarded hot plate has been used
Method C177.
successfully over a mean temperature range from − 10
3.2 Definitions of Terms Specific to This Standard:
to+65°C, with circular metal plates and a single line-heat
3.2.1 gap, n—a separation between the meter plate and
source in the meter plate. The chronological development of
guard plate, usually filled with a gas or thermal insulation.
the design of circular line-heat-source guarded hot plates is
3.2.2 guard plate, n—theouterringoftheguardedhotplate
2
given in Refs (1-8).
that encompasses the meter plate and promotes one-
1.5 This practice does not preclude (1) lower or higher
dimensional heat flow normal to the meter plate.
temperatures; (2) plate geometries other than circular; (3)
3.2.3 guarded hot plate, n—an assembly, consisting of a
line-heat-source geometries other than circular; (4) the use of
meter plate and a co-planar, concentric guard plate, that
platesfabricatedfromceramics,composites,orothermaterials;
provides the heat input to the specimens.
or (5) the use of multiple line-heat sources in both the meter
3.2.4 line-heat-source, n—a thin or fine electrical heating
and guard plates.
element that provides uniform heat generation per unit length.
1
This practice is under the jurisdiction of ASTM Committee C16 on Thermal
Insulation and is the direct responsibility of Subcommittee C16.30 on Thermal
Measurement.
Current edition approved Sept. 10, 1997. Published June 1998. Originally
3
published as C1043–85. Last previous edition C1043–96. Annual Book of ASTM Standards, Vol 04.06.
2 4
The boldface numbers in parentheses refer to a list of references at the end of Annual Book of ASTM Standards, Vol 14.03.
5
this practice. Available from ASTM Headquarters. Order Adjunct: ADJC1043.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
1

---------------------- Page: 1 ----------------------
C1043
3.2.5 meter area, n—the mathematical area through which guardingisa
...

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1.1 This practice provides the user with a uniform procedure for calculating the thermal transmission properties of a material or system from data generated by steady state, one dimensional test methods used to determine heat flux and surface temperatures. This practice is intended to eliminate the need for similar calculation sections in Test Methods C177, C335, C518, C1033, C1114 and C1363 and Practices C1043 and C1044 by permitting use of these standard calculation forms by reference.  
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Standard Test Method for Steady-State Thermal Transmission Properties by Means of the Thin-Heater Apparatus

SIGNIFICANCE AND USE
5.1 Factors that may influence the thermal-transmission properties of a specimen of material are described in Practice C1045 and the Precision and Bias section of Test Method C177.  
5.2 Because of the required test conditions prescribed by this test method, it shall be recognized that the thermal properties obtained will not necessarily apply without modification to all conditions of service. As an example, this test method normally provides that the thermal properties shall be obtained on specimens that do not contain moisture, although in service such conditions may not be realized. Even more basic is the dependence of the thermal properties on variables such as mean temperature and temperature difference.  
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SCOPE
1.1 This test method covers the determination of the steady-state thermal transmission properties of flat-slab specimens of thermal insulation using a thin heater of uniform power density having low lateral heat flow. A thin heater with low lateral thermal conductance can reduce unwanted lateral heat flow and avoid the need for active-edge guarding.  
1.2 This primary test method of thermal-transmission measurement describes a principle, rather than a particular apparatus. The principle involves determination of the thermal flux across a specimen of known thickness and the temperatures of the hot and cold faces of the specimen.  
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1.4.2 The remainder of the specimen should not distort the heat flow in that part of the specimen defined in 1.4.1.  
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Standard Practice for Guarded-Hot-Plate Design Using Circular Line-Heat Sources

SIGNIFICANCE AND USE
4.1 This practice describes the design of a guarded hot plate with circular line-heat sources and provides guidance in determining the mean temperature of the meter plate. It provides information and calculation procedures for: (1) control of edge heat loss or gain (Annex A1); (2) location and installation of line-heat sources (Annex A2); (3) design of the gap between the meter and guard plates (Appendix X1); and (4) location of heater leads for the meter plate (Appendix X2).  
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4.4 A guarded hot plate with one or more line-heat sources will have a radial temperature variation, with the maximum temperature differences being quite small compared to the average temperature drop across the specimens. Provided guarding is adequate, only the mean surface temperature of the meter plate enters into calculations of thermal transmission properties.  
4.5 Care shall be taken to design a circular line-heat-source guarded hot plate so that the electric-current leads to each heater either do not significantly alter the temperature distributions in the meter and guard plates or else affect these temperature distributions in a known way so that appropriate corrections are applied.  
4.6 The use of one or a few ...
SCOPE
1.1 This practice covers the design of a circular line-heat-source guarded hot plate for use in accordance with Test Method C177.  
Note 1: Test Method C177 describes the guarded-hot-plate apparatus and the application of such equipment for determining thermal transmission properties of flat-slab specimens. In principle, the test method includes apparatus designed with guarded hot plates having either distributed- or line-heat sources.  
1.2 The guarded hot plate with circular line-heat sources is a design in which the meter and guard plates are circular plates having a relatively small number of heaters, each embedded along a circular path at a fixed radius. In operation, the heat from each line-heat source flows radially into the plate and is transmitted axially through the test specimens.  
1.3 The meter and guard plates are fabricated from a continuous piece of thermally conductive material. The plates are made sufficiently thick that, for typical specimen thermal conductances, the radial and axial temperature variations in the guarded hot plate are quite small. By proper location of the line-heat source(s), the temperature at the edge of the meter plate is made equal to the mean temperature of the meter plate, thus facilitating temperature measurements and thermal guarding.  
1.4 The line-heat-source guarded hot plate has been used successfully over a mean temperature range from − 10 to + 65°C, with circular metal plates and a single line-heat source in the meter plate. The chronological development of the design of circular line-heat-source guarded hot plates is given in Refs (1-9).2
Note 2: Detailed drawings and descriptions for the construction of two line-heat-source guarded-hot-plate apparatuses are available in the adjunct.3  
1.5 This practice does not preclude (1) lower or higher temperatures; (2) plate geometries other than circular; (3) line-heat-source geometries other than circular; (4) the use of...

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ASTM
ASTM C177-19e1(Test Method)
Standard Test Method for Steady-State Heat Flux Measurements and Thermal Transmission Properties by Means of the Guarded-Hot-Plate Apparatus

SIGNIFICANCE AND USE
5.1 This test method covers the measurement of heat flux and associated test conditions for flat specimens. The guarded-hot-plate apparatus is generally used to measure steady-state heat flux through materials having a “low” thermal conductivity and commonly denoted as “thermal insulators.” Acceptable measurement accuracy requires a specimen geometry with a large ratio of area to thickness.  
5.2 Two specimens are selected with their thickness, areas, and densities as identical as possible, and one specimen is placed on each side of the guarded-hot-plate. The faces of the specimens opposite the guarded-hot-plate and primary guard are placed in contact with the surfaces of the cold surface assemblies.  
5.3 Steady-state heat transmission through thermal insulators is not easily measured, even at room temperature. This is due to the fact heat transmission through a specimen occurs by any or all of three separate modes of heat transfer (radiation, conduction, and convection). It is possible that any inhomogeneity or anisotropy in the specimen will require special experimental precautions to measure that flow of heat. In some cases it is possible that hours or even days will be required to achieve the thermal steady-state. No guarding system can be constructed to force the metered heat to pass only through the test area of insulation specimen being measured. It is possible that moisture content within the material will cause transient behavior. It is also possible that and physical or chemical change in the material with time or environmental condition will permanently alter the specimen.  
5.4 Application of this test method on different test insulations requires that the designer make choices in the design selection of materials of construction and measurement and control systems. Thus it is possible that there will be different designs for the guarded-hot-plate apparatus when used at ambient versus cryogenic or high temperatures. Test thickness, temperature range,...
SCOPE
1.1 This test method establishes the criteria for the laboratory measurement of the steady-state heat flux through flat, homogeneous specimen(s) when their surfaces are in contact with solid, parallel boundaries held at constant temperatures using the guarded-hot-plate apparatus.  
1.2 The test apparatus designed for this purpose is known as a guarded-hot-plate apparatus and is a primary (or absolute) method. This test method is comparable, but not identical, to ISO 8302.  
1.3 This test method sets forth the general design requirements necessary to construct and operate a satisfactory guarded-hot-plate apparatus. It covers a wide variety of apparatus constructions, test conditions, and operating conditions. Detailed designs conforming to this test method are not given but must be developed within the constraints of the general requirements. Examples of analysis tools, concepts and procedures used in the design, construction, calibration and operation of a guarded-hot-plate apparatus are given in Refs (1-41).2  
1.4 This test method encompasses both the single-sided and the double-sided modes of measurement. Both distributed and line source guarded heating plate designs are permitted. The user should consult the standard practices on the single-sided mode of operation, Practice C1044, and on the line source apparatus, Practice C1043, for further details on these heater designs.  
1.5 The guarded-hot-plate apparatus can be operated with either vertical or horizontal heat flow. The user is cautioned however, since the test results from the two orientations may be different if convective heat flow occurs within the specimens.  
1.6 Although no definitive upper limit can be given for the magnitude of specimen conductance that is measurable on a guarded-hot-plate, for practical reasons the specimen conductance should be less than 16 W/(m2K).  
1.7 This test method is applicable to the measurement of a wide variety of sp...

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ASTM
ASTM E473-23b(Terminology)
Standard Terminology Relating to Thermal Analysis and Rheology

SCOPE
1.1 This terminology is a compilation of definitions of terms used in ASTM documents relating to thermal analysis and rheology. This terminology includes only those terms for which ASTM either has standards or is contemplating some action. It is not intended to be an all-inclusive listing of terms related to thermal analysis and rheology.  
1.2 This terminology specifically supports the single-word form for terms using thermo as a prefix, such as thermoanalytical or thermomagnetometry, while recognizing that for some terms a two-word form can be used, such as thermal analysis. This terminology does not support, nor does it recommend, use of the grammatically incorrect, single-word form using thermal as a prefix, such as, thermalanalytical or thermalmagnetometry.  
1.3 A definition is a single sentence with additional information included in a Discussion area. It is reviewed every five years.  
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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ASTM
ASTM E1142-23b(Terminology)
Standard Terminology Relating to Thermophysical Properties

SCOPE
1.1 This is a compilation of only those terms and corresponding definitions included in or being considered for inclusion in ASTM documents relating to thermophysical properties. It is not intended as an all-inclusive listing of thermophysical property terms. Terms that are generally understood or defined adequately in other readily available sources are not included.  
1.2 A definition is a single sentence with additional information included in a Discussion.  
1.3 Definitions of terms specific to a particular field (such as dynamic mechanical measurements) are identified with an italicized introductory phrase.  
1.4 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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