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ASTM C1784-13

(Test Method)

Standard Test Method for Using a Heat Flow Meter Apparatus for Measuring Thermal Storage Properties of Phase Change Materials and Products

Standard Test Method for Using a Heat Flow Meter Apparatus for Measuring Thermal Storage Properties of Phase Change Materials and Products

SIGNIFICANCE AND USE
5.1 Materials used in building envelopes to enhance energy efficiency, including PCM products used for thermal insulation, thermal control, and thermal storage, are subjected to transient thermal environments, including transient or cyclic boundary temperature conditions. This test method is intended to enable meaningful PCM product classification, as steady-state thermal conductivity alone is not sufficient to characterize PCMs.Note 3—This test method defines a dynamic test protocol for complex products or composites containing PCMs. Due to the macroscopic structure of these products or composites, conventional measurements using a Differential Scanning Calorimeter (DSC) as specified in E793 and E967, which use very small samples, are not representative of the relationship between temperature and enthalpy storage of full-scale PCM products due to the sample size limitation.  
5.2 Dynamic measurements of the thermal performance of PCM products shall only be performed by qualified personnel with understanding of heat transfer and error propagation. Familiarity with the configuration of both the apparatus and the product is necessary.  
5.3 This test method focuses on testing PCM products used in engineering applications, including in building envelopes to enhance the thermal performance of insulation systems.  
5.3.1 Applications of PCM in building envelopes take multiple forms, including: dispersed in, or otherwise combined with, a thermal insulation material; a separate object implemented in the building envelope as boards or membranes containing concentrated PCM that operates in conjunction with a thermal insulation material. Both of these forms enhance the performance of the structure when exposed to dynamic, that is, fluctuating, boundary temperature conditions.  
5.3.2 PCMs can be studied in a variety of forms: as the original “pure” PCM; as a composite containing PCM and other embedded materials to enhance thermal performance; as a product containing PCM o...
SCOPE
1.1 This test method covers the measurement of non-steady-state heat flow into or out of a flat slab specimen to determine the stored energy (that is, enthalpy) change as a function of temperature using a heat flow meter apparatus (HFMA).  
1.2 In particular, this test method is intended to measure the sensible and latent heat storage capacity for products incorporating phase-change materials (PCM).  
1.2.1 The storage capacity of a PCM is well defined via four parameters: specific heats of both solid and liquid phases, phase change temperature(s) and phase change enthalpy (1).2  
1.3 To more accurately predict thermal performance, information about the PCM products’ performance under dynamic conditions is needed to supplement the properties (thermal conductivity) measured under steady-state conditions.Note 1—This test method defines a dynamic test protocol for products or composites containing PCMs. Due to the macroscopic structure of these products or composites, small sample sizes used in conventional Differential Scanning Calorimeter (DSC) measurements, as specified in E793 and E967, are not representative of the relationship between temperature and enthalpy storage of full-scale PCM products.  
1.4 This test method is based upon the HFMA technology used for Test Method C518 but includes modifications for specific heat and enthalpy change measurements for PCM products as outlined in this test method.  
1.5 Heat flow measurements are required at both the top and bottom HFMA plates for this test method. Therefore, this test method applies only to HFMAs that are equipped with at least one heat flux transducer on each of the two plates and that have the capability for computerized data acquisition and temperature control systems. Further, the amount of energy flowing through the transducers must be measureable at all points in time. Therefore, the transducer output shall never be saturated during a test.  
1.6 This...

General Information

Status
Historical
Publication Date
31-Oct-2013
ICS
17.200.10 - Heat. Calorimetry
Technical Committee
C16 - Thermal Insulation
Drafting Committee
C16.30 - Thermal Measurement
Current Stage
Ref Project

Relations

Replaced By
ASTM C1784-14 - Standard Test Method for Using a Heat Flow Meter Apparatus for Measuring Thermal Storage Properties of Phase Change Materials and Products
Effective Date
01-Oct-2014

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ASTM C1784-13 - Standard Test Method for Using a Heat Flow Meter Apparatus for Measuring Thermal Storage Properties of Phase Change Materials and ProductsASTM C1784-13 - Standard Test Method for Using a Heat Flow Meter Apparatus for Measuring Thermal Storage Properties of Phase Change Materials and Products
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ASTM C1784-13 - Standard Test Method for Using a Heat Flow Meter Apparatus for Measuring Thermal Storage Properties of Phase Change Materials and Products
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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: C1784 − 13
StandardTest Method for
Using a Heat Flow Meter Apparatus for Measuring Thermal
Storage Properties of Phase Change Materials and
1
Products
This standard is issued under the fixed designation C1784; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 1.6 This test method makes a series of measurements to
determine the enthalpy storage of a test specimen over a
1.1 Thistestmethodcoversthemeasurementofnon-steady-
temperature range. First, both HFMA plates are held at the
state heat flow into or out of a flat slab specimen to determine
same constant temperature until steady state is achieved.
the stored energy (that is, enthalpy) change as a function of
Steadystateisdefinedbythereductionintheamountofenergy
temperature using a heat flow meter apparatus (HFMA).
entering the specimen from both plates to a very small and
1.2 In particular, this test method is intended to measure the
nearly constant value. Next, both plate temperatures are
sensible and latent heat storage capacity for products incorpo-
changed by identical amounts and held at the new temperature
rating phase-change materials (PCM).
until steady state is again achieved. The enthalpy absorbed or
1.2.1 ThestoragecapacityofaPCMiswelldefinedviafour
released by the specimen from the time of the temperature
parameters: specific heats of both solid and liquid phases,
change until steady state is again achieved will be recorded.
2
phase change temperature(s) and phase change enthalpy (1).
Using a series of temperature step changes, the cumulative
1.3 To more accurately predict thermal performance, infor- enthalpy stored or released over a certain temperature range is
determined.
mation about the PCM products’ performance under dynamic
conditions is needed to supplement the properties (thermal
1.6.1 The specific heats of the solid and liquid phases are
conductivity) measured under steady-state conditions.
determined from the slope of the sensible enthalpy storage as
NOTE 1—This test method defines a dynamic test protocol for products
a function of temperature, before and after the phase change
orcompositescontainingPCMs.Duetothemacroscopicstructureofthese
process.
products or composites, small sample sizes used in conventional Differ-
ential Scanning Calorimeter (DSC) measurements, as specified in E793
1.7 Calibration of the HFMA to determine the ‘correction
and E967, are not representative of the relationship between temperature
factors’ for the enthalpy stored within the plate heat flux
and enthalpy storage of full-scale PCM products.
transducers and any material placed between the test specimen
1.4 This test method is based upon the HFMA technology
and the HFMAplates must be performed following AnnexA1.
used for Test Method C518 but includes modifications for
These correction factors are functions of the beginning and
specific heat and enthalpy change measurements for PCM
ending temperatures for each step, as described in Annex A1.
products as outlined in this test method.
1.8 This test method applies to PCMs and composites,
1.5 Heatflowmeasurementsarerequiredatboththetopand
products and systems incorporating PCMs, including: dis-
bottom HFMA plates for this test method. Therefore, this test
persed in, or combined with, a thermal insulation material,
method applies only to HFMAs that are equipped with at least
boards or membranes containing concentrated or dispersed
oneheatfluxtransduceroneachofthetwoplatesandthathave
PCM, etc. Specific examples include solid PCM composites
the capability for computerized data acquisition and tempera-
andproducts,looseblendedmaterialsincorporatingPCMs,and
ture control systems. Further, the amount of energy flowing
discretely contained PCM.
through the transducers must be measureable at all points in
1.9 This test method may be used to characterize material
time. Therefore, the transducer output shall never be saturated
properties, which may or may not be representative of actual
during a test.
conditions of use.
1
ThistestmethodisunderthejurisdictionofASTMCommitteeC16onThermal
1.10 The values stated in SI units are to be regarded as
Insulation and is the direct responsibility of Subcommittee C16.30 on Thermal
standard. No other units of measurement are included in this
Measurement.
standard.
Current edition approved Nov. 1, 2013. Published January 2014. DOI: 10.1520/
C1784-13.
2 1.11 This standard does not purport to address all of the
The boldface numbers in parentheses refer to the list of references at the end of
this standard. safety concerns, if any, associated with its use. It is the
Copyright
...

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ASTM C1130-21(Practice)
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5.1 The application of HFTs and temperature sensors to building envelopes provide in-situ data for evaluating the thermal performance of an opaque building component under actual environmental conditions, as described in Practices C1046 and C1155. These applications require calibration of the HFTs at levels of heat flux and temperature consistent with end-use conditions.  
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5.2.2 The resulting voltage output, E, of the heat flux transducer is measured directly using (auxiliary) readout instrumentation connected to the electrical output leads of the sensor.
Note 1: A heat flux transducer (see also Terminology C168) is a thin stable substrate having a low mass in which a temperature difference across the thickness of the device is measured with thermocouples connected electrically in series (that is, a thermopile). Commercial HFTs typically have a central sensing region, a surrounding guard, and an integral temperature sensor that are contained in a thin durable enclosure. Practice C1046, Appendix X2 includes detailed descriptions of the internal constructions of two types of HFTs.  
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1.1 This practice, in conjunction with either Test Method C177, C518, C1114, or C1363, establishes procedures for the calibration of heat flux transducers that are dimensionally thin in comparison to their planar dimensions.  
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1.2 This practice describes techniques for determining the sensitivity, S, of a heat flux transducer when subjected to one dimensional heat flow normal to the planar surface or when installed in a building application.  
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4.1 This practice provides a procedure for operating the apparatus so that the heat flow, Q′, through the meter section of the auxiliary insulation is small; determining Q′; and, calculating the heat flow, Q, through the meter section of the specimen.  
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1.1 This test method covers the measurement of non-steady-state heat flow into or out of a flat slab specimen to determine the stored energy (that is, enthalpy) change as a function of temperature using a heat flow meter apparatus (HFMA).  
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1.3 To more accurately predict thermal performance, information about the PCM products’ performance under dynamic conditions is needed to supplement the properties (thermal conductivity) measured under steady-state conditions.
Note 1: This test method defines a dynamic test protocol for products or composites containing PCMs. Due to the macroscopic structure of these products or composites, small specimen sizes used in conventional Differential Scanning Calorimeter (DSC) measurements, as specified in E793 and E967, are not necessarily representative of the relationship between temperature and enthalpy of full-scale PCM products.  
1.4 This test method is based upon the HFMA technology used for Test Method C518 but includes modifications for specific heat and enthalpy change measurements for PCM products as outlined in this test method.  
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4.1 ASTM thermal test method descriptions are complex because of added apparatus details necessary to ensure accurate results. As a result, many users find it difficult to locate the data reduction details necessary to reduce the data obtained from these tests. This practice is designed to be referenced in the thermal test methods, thus allowing those test methods to concentrate on experimental details rather than data reduction.  
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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.  
1.2 The thermal transmission properties described include: thermal conductance, thermal resistance, apparent thermal conductivity, apparent thermal resistivity, surface conductance, surface resistance, and overall thermal resistance or transmittance.  
1.3 This practice provides the method for developing the apparent thermal conductivity as a function of temperature relationship for a specimen from data generated by standard test methods at small or large temperature differences. This relationship can be used to characterize material for comparison to material specifications and for use in calculation programs such as Practice C680.  
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1.5 This practice includes a discussion of the definitions and underlying assumptions for the calculation of thermal transmission properties. Tests to detect deviations from these assumptions are described. This practice also considers the complicating effects of uncertainties due to the measurement processes and material variability. See Section 7.  
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ASTM C1114-06(2019)(Test Method)
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.  
5.3 When a new or modified design of apparatus is evolved, tests shall be made on at least two sets of differing material of known long-term thermal stability. Tests shall be made for each material at a minimum of two different mean temperatures within the operating range of each. Any differences in results should be carefully studied to determine the cause and then be removed by appropriate action. Only after a successful verification study on materials having known thermal properties traceable to a recognized national standards laboratory shall test results obtained with this apparatus be considered to conform with this test method. Periodic checks of apparatus performance are recommended.  
5.4 The thermal transmission properties of many materials depend upon the prior thermal history. Care must be exercised when testing such specimens at a number of conditions so that tests are performed in a sequence that limits such effects on the results.  
5.5 Typical uses for the thin-heater apparatus include the following:  
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5.5.2 Measurement of thermal conductivity at desired mean temperatures.  
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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.  
1.3 Considerable latitude is given to the designer of the apparatus in this test method; since a variety of designs is possible, a procedure for qualifying an apparatus is given in 5.3.  
1.4 The specimens must meet the following conditions if thermal resistance or thermal conductance of the specimen is to be determined by this test method2:  
1.4.1 The portion of the specimen over the isothermal area of the heater must accurately represent the whole specimen.  
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.  
1.4.3 The specimen shall be thermally homogeneous such that the thermal conductivity is not a function of the position within the sample, but rather may be a function of direction, time, and temperature. The specimen shall be free of holes, of high-density volumes, and of thermal bridges between the test surfaces or the specimen edges.  
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ASTM C1043-19(Practice)
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).  
4.2 A circular guarded hot plate with one or more line-heat sources is amenable to mathematical analysis so that the mean surface temperature is calculated from the measured power input and the measured temperature(s) at one or more known locations. Further, a circular plate geometry simplifies the mathematical analysis of errors resulting from heat gains or losses at the edges of the specimens (see Refs (10, 11)).  
4.3 The line-heat source(s) is (are) placed in the meter plate at a prescribed radius such that the temperature at the outer edge of the meter plate is equal to the mean surface temperature over the meter area. Thus, the determination of the mean temperature of the meter plate is accomplished with a small number of temperature sensors placed near the gap.  
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 ...
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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,...
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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 E473-23b(Terminology)
Standard Terminology Relating to Thermal Analysis and Rheology

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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 E2070-23(Test Method)
Standard Test Methods for Kinetic Parameters by Differential Scanning Calorimetry Using Isothermal Methods

SIGNIFICANCE AND USE
6.1 These test methods are useful for research and development, quality assurance, regulatory compliance, and specification acceptance purposes.  
6.2 The determination of the order of a chemical reaction or transformation at specific temperatures or time conditions is beyond the scope of these test methods.  
6.3 The activation energy results obtained by these test methods may be compared with those obtained from Test Method E698 for nth order and accelerating reactions. Activation energy, pre-exponential factor, and reaction order results by these test methods may be compared to those for Test Method E2041 for nth order reactions.
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1.1 Test Methods A, B, and C determine kinetic parameters for activation energy, pre-exponential factor and reaction order using differential scanning calorimetry (DSC) from a series of isothermal experiments over a small (≈10 K) temperature range. Test Method A is applicable to low nth order reactions. Test Methods B and C are applicable to accelerating reactions such as thermoset curing or pyrotechnic reactions and crystallization transformations in the temperature range from 300 K to 900 K (nominally 30 °C to 630 °C). These test methods are applicable only to these types of exothermic reactions when the thermal curves do not exhibit shoulders, double peaks, discontinuities or shifts in baseline.  
1.2 Test Methods D and E also determines the activation energy of a set of time-to-event and isothermal temperature data generated by this or other procedures  
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.4 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific precautionary statements are given in Section 8.  
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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