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ASTM C1130-07(2012)

(Practice)

Standard Practice for Calibrating Thin Heat Flux Transducers

Standard Practice for Calibrating Thin Heat Flux Transducers

SIGNIFICANCE AND USE
4.1 The use of heat flux transducers on building envelope components provides the user with a means for performing in-situ heat flux measurements. Accurate translation of the heat flux transducer output requires a complete understanding of the factors affecting its output, and a standardized method for determining the heat flux transducer sensitivity for the application of interest.  
4.2 The sensitivity of the heat flux transducer is determined primarily by the sensor construction and temperature of operation and the details of the application, including geometry, material characteristics, and environmental factors.Note 1—Practice C1046 includes an excellent description of heat flux transducer construction.  
4.3 The presence of a heat flux transducer is likely to alter the heat flux that is being measured. To determine the heat flow that would occur in the absence of the transducer, it is necessary to either:  
4.3.1 Ensure that the installation is adequately guarded (1).3  
4.3.2 Adjust the results based on a detailed model or numerical analysis. Such analysis is beyond the scope of this practice, but details can be found in (2-6).  
4.3.3 Use the empirically measured heat flux transducer sensitivity measured under conditions that adequately simulate the conditions of use in the final application.  
4.4 There are several methods for determining the sensitivity of heat flux transducers, including Test Methods C177, C518, C1114, and C1363. The selection of the appropriate procedure will depend on the required accuracy and the physical limitations of available equipment.  
4.5 This practice describes techniques to establish uniform heat flow normal to the heat flux transducer for the determination of the heat flux transducer sensitivity.  
4.6 The method of heat flux transducer application must be adequately simulated or duplicated when experimentally determining the heat flux transducer sensitivity. The two most widely used application techniques are to su...
SCOPE
1.1 This practice, in conjunction with Test Method C177, C518, C1114, or C1363, establishes an experimental procedure for determining the sensitivity of heat flux transducers that are relatively thin.  
1.1.1 For the purpose of this standard, the thickness of the heat flux transducer shall be less than 30 % of the narrowest planar dimension of the heat flux transducer.  
1.2 This practice discusses a method for determining the sensitivity of a heat flux transducer to one-dimensional heat flow normal to the surface and for determining the sensitivity of a heat flux transducer for an installed application.  
1.3 This practice should be used in conjunction with Practice C1046 when performing in-situ measurements of heat flux on opaque building components.  
1.4 This practice is not intended to determine the sensitivity of heat flux transducers that are components of heat flow meter apparatus, as in Test Method C518.  
1.5 This practice is not intended to determine the sensitivity of heat flux transducers used for in-situ industrial applications that are covered in Practice C1041.  
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
31-Aug-2012
ICS
17.200.10 - Heat. Calorimetry
Technical Committee
C16 - Thermal Insulation
Drafting Committee
C16.30 - Thermal Measurement
Current Stage
Ref Project

Relations

Replaces
ASTM C1130-07 - Standard Practice for Calibrating Thin Heat Flux Transducers
Effective Date
01-Sep-2012
Referred By
ASTM C1363-19 - Standard Test Method for Thermal Performance of Building Materials and Envelope Assemblies by Means of a Hot Box Apparatus
Effective Date
01-Sep-2012
Referred By
ASTM C1470-20 - Standard Guide for Testing the Thermal Properties of Advanced Ceramics
Effective Date
01-Sep-2012
Referred By
ASTM E2684-17 - Standard Test Method for Measuring Heat Flux Using Surface-Mounted One-Dimensional Flat Gages
Effective Date
01-Sep-2012
Referred By
ASTM C1155-95(2021) - Standard Practice for Determining Thermal Resistance of Building Envelope Components from the In-Situ Data
Effective Date
01-Sep-2012
Referred By
ASTM C1046-95(2021) - Standard Practice for In-Situ Measurement of Heat Flux and Temperature on Building Envelope Components
Effective Date
01-Sep-2012

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ASTM C1130-07(2012) - Standard Practice for Calibrating Thin Heat Flux TransducersASTM C1130-07(2012) - Standard Practice for Calibrating Thin Heat Flux Transducers
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ASTM C1130-07(2012) - Standard Practice for Calibrating Thin Heat Flux Transducers
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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: C1130 − 07 (Reapproved 2012)
Standard Practice for
Calibrating Thin Heat Flux Transducers
This standard is issued under the fixed designation C1130; 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 the Guarded-Hot-Plate Apparatus
C518 Test Method for Steady-State Thermal Transmission
1.1 This practice, in conjunction with Test Method C177,
Properties by Means of the Heat Flow Meter Apparatus
C518, C1114,or C1363, establishes an experimental procedure
C1041 Practice for In-Situ Measurements of Heat Flux in
for determining the sensitivity of heat flux transducers that are
Industrial Thermal Insulation Using Heat Flux Transduc-
relatively thin.
ers
1.1.1 For the purpose of this standard, the thickness of the
C1044 Practice for Using a Guarded-Hot-PlateApparatus or
heat flux transducer shall be less than 30 % of the narrowest
Thin-Heater Apparatus in the Single-Sided Mode
planar dimension of the heat flux transducer.
C1046 Practice for In-Situ Measurement of Heat Flux and
1.2 This practice discusses a method for determining the
Temperature on Building Envelope Components
sensitivity of a heat flux transducer to one-dimensional heat
C1114 Test Method for Steady-State Thermal Transmission
flow normal to the surface and for determining the sensitivity
Properties by Means of the Thin-Heater Apparatus
of a heat flux transducer for an installed application.
C1155 Practice for Determining Thermal Resistance of
Building Envelope Components from the In-Situ Data
1.3 This practice should be used in conjunction with Prac-
tice C1046 when performing in-situ measurements of heat flux C1363 Test Method for Thermal Performance of Building
Materials and Envelope Assemblies by Means of a Hot
on opaque building components.
Box Apparatus
1.4 This practice is not intended to determine the sensitivity
of heat flux transducers that are components of heat flow meter
3. Terminology
apparatus, as in Test Method C518.
3.1 Definitions—For definitions of terms relating to thermal
1.5 This practice is not intended to determine the sensitivity
insulating materials, see Terminology C168.
of heat flux transducers used for in-situ industrial applications
3.2 Definitions of Terms Specific to This Standard:
that are covered in Practice C1041.
3.2.1 mask—material (or materials) having the same, or
1.6 This standard does not purport to address all of the
nearly the same, thermal properties and thickness surrounding
safety concerns, if any, associated with its use. It is the
the heat flux transducer thereby promoting one-dimensional
responsibility of the user of this standard to establish appro-
heat flow through the heat flux transducer.
priate safety and health practices and determine the applica-
3.2.2 sensitivity—theratiooftheelectricaloutputoftheheat
bility of regulatory limitations prior to use.
flux transducer to the heat flux passing through the device
when measured under steady-state heat flow.
2. Referenced Documents
3.2.3 test stack—a layer or a series of layers of material put
2.1 ASTM Standards:
together to comprise a test sample (for example, a roof system
C168 Terminology Relating to Thermal Insulation
containing a membrane, an insulation, and a roof deck).
C177 Test Method for Steady-State Heat Flux Measure-
2 2
ments and Thermal Transmission Properties by Means of 3.3 Symbols: R = thermal resistance, m ·K/W (h·ft ·F /Btu)
2 2
q = heat flux, W/m (Btu⁄h·ft )
Q = heat flux expected in application,
expected
2 2
This practice is under the jurisdiction of ASTM Committee C16 on Thermal
W/m (Btu⁄h·ft )
Insulation and is the direct responsibility of Subcommittee C16.30 on Thermal
E = measured output voltage, V
Measurement.
2 2
S = sensitivity, V/(W/m ) (V⁄(Btu⁄hr·ft ))
Current edition approved Sept. 1, 2012. Published November 2012. Originally
∆T = temperature difference, K (°F)
approved in 1989. Last previous edition approved in 2007 as C1130 – 07. DOI:
10.1520/C1130-07R12.
R = thermal resistance of a layer in the test stack,
layer
For referenced ASTM standards, visit the ASTM website, www.astm.org, or 2 2
m ·K/W (h·ft ·F /Btu)
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
T = temperature, K (°F)
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. u = combined standard uncertainty
c
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C1130 − 07 (2012)
u = standard uncertainty of the regression coefficients 5.1.2 When bringing the heat flux transducer voltage leads
u = standard uncertainty for replicate measurements out of the test instrument, take care to avoid air gaps in the
u = standard uncertainty for the measurement mask or between the sample stack and the test instrument. Fill
ε = error term airgapswithaconformablematerial,suchastoothpaste,caulk,
or putty, or cover with tape.
4. Significance and Use
NOTE3—Theheatfluxtransducersdonotneedtobephysicallyadhered
4.1 The use of heat flux transducers on building envelope
to the mask or embedding material but should fit well enough to assure
good thermal contact. If needed, apply thermally conductive gel to one or
components provides the user with a means for performing
both faces of the heat flux transducer to improve the thermal contact.
in-situ heat flux measurements.Accurate translation of the heat
Materialcompatibilitymustbeconsideredintheselectionofanysuchgel.
fluxtransduceroutputrequiresacompleteunderstandingofthe
5.1.3 Place a temperature sensor on or near the heat flux
factors affecting its output, and a standardized method for
transducer. Connect temperature sensor(s) applied to the heat
determining the heat flux transducer sensitivity for the appli-
flux transducer to a readout device.
cation of interest.
5.1.4 When compressible insulation is included in the test
4.2 The sensitivity of the heat flux transducer is determined
stack, manually control the distance between the hot and cold
primarily by the sensor construction and temperature of opera-
apparatus surfaces.
tion and the details of the application, including geometry,
5.1.5 The heat flux transducer(s) must be located within the
material characteristics, and environmental factors.
metered area of the apparatus. In a hot box apparatus, mount
NOTE 1—Practice C1046 includes an excellent description of heat flux
the heat flux transducers in the central portion of the metered
transducer construction.
area of the test panel.
4.3 The presence of a heat flux transducer is likely to alter
theheatfluxthatisbeingmeasured.Todeterminetheheatflow 5.2 Three separate test stack preparations are discussed to
that would occur in the absence of the transducer, it is determine appropriately: the one-dimensional sensitivity, the
necessary to either: sensitivity for embedded configurations, and the sensitivity for
4.3.1 Ensure that the installation is adequately guarded (1). surface-mounted configurations.
4.3.2 Adjust the results based on a detailed model or
5.3 One-Dimensional Sensitivity—The heat flux transducer
numerical analysis. Such analysis is beyond the scope of this
shall be embedded in a test stack and surrounded with a mask,
practice, but details can be found in (2-6).
as shown in Fig. 1.
4.3.3 Use the empirically measured heat flux transducer
5.3.1 The test stack shall consist of a sandwich of the heat
sensitivity measured under conditions that adequately simulate
flux transducer/masking layer between two layers of a com-
the conditions of use in the final application.
pressible homogeneous material, such as high-density fibrous
4.4 There are several methods for determining the sensitiv- glass insulation board, to assure good thermal contact between
ity of heat flux transducers, including Test Methods C177,
the plates of the tester and the heat flux transducer/masking
C518, C1114, and C1363. The selection of the appropriate layer.
procedure will depend on the required accuracy and the
5.3.2 The mask must have the same thickness and thermal
physical limitations of available equipment.
resistance as the heat flux transducer.
5.3.3 The mask or embedding material should be signifi-
4.5 This practice describes techniques to establish uniform
cantly larger than the metering area of the test equipment and
heat flow normal to the heat flux transducer for the determi-
ideally be the same size as the plates of the apparatus.
nation of the heat flux transducer sensitivity.
5.3.4 To measure the sensitivity of multiple small heat flux
4.6 The method of heat flux transducer application must be
transducers, the heat flux transducer/mask layer shown in Fig.
adequately simulated or duplicated when experimentally deter-
1 is replaced with a layer containing an arrangement of
mining the heat flux transducer sensitivity. The two most
transducers located within the metered area of the apparatus as
widely used application techniques are to surface-mount the
illustrated in Fig. 2.
heat flux transducer or to embed the heat flux transducer in the
5.4 Sensitivity, Embedded Configuration—Place the heat
insulation system.
NOTE 2—The difference between the sensitivity under uniform normal flux transducer, in a fashion identical to its end use application,
heat flow versus that for the surface-mounted or embedded configurations
in a test stack duplicating the building construction to be
has been demonstrated using multiple mathematical techniques (7-9).
evaluated. An example of a test stack, for the case where the
heat flux transducer is to be embedded in gypsum wallboard
5. Specimen Preparation
facing an insulated wall cavity, is shown in Fig. 3.
5.1 Specimen Preparation for All Cases:
5.5 Sensitivity, Surface-Mounted Configuration—Apply the
5.1.1 Check the electrical continuity of the heat flux trans-
heat flux transducer in a manner identical to that of actual use
ducer. Connect the heat flux transducer voltage leads to the
as specified in Practice C1046. Important considerations for
auxiliary measurement equipment (for example, voltmeter)
surfacemountingincludethermalcontactbetweentheheatflux
having a resolution of 6 2 µV or better.
transducerandthesurfaceandmatchingoftheemittanceofthe
heat flux transducer and test construction.An example of a test
arrangement, for the case where the heat flux transducer is to
The boldface numbers in parentheses refer to the references at the end of this
standard. be surface-mounted, is shown in Fig. 4.
C1130 − 07 (2012)
FIG. 1 Example of a Test Stack Used to Measure Heat Flux Transducer Sensitivity, Side View
NOTE 1—Some apparatus metering areas are round.
FIG. 2 Top View of the Heat Flux Transducer/Mask Layer Within the Test Stack for the Case Where Multiple Small Heat Flux Transduc-
ers are Evaluated Simultaneously
NOTE 4—In many cases, several surface-mounted heat flux transducers
the heat flux through the heat flux transducer.Apparatuses that
will be used at one time and can be analyzed for sensitivity simultane-
typically require two samples should be operated in the
ously.
single-sided mode in conformance with Practice C1044.
6. Procedure
6.2 Vary the hot- and cold-surface plates of the test instru-
ment to produce the range of heat fluxes and mean tempera-
6.1 Use a guarded-hot-plate, heat flow meter, hot box, or
thin-heater apparatus. Follow Test Method C177, C518, tures according to the guidance found in Appendix X1 and
C1363,or C1114, including test stack conditioning, to measure Appendix X2.
C1130 − 07 (2012)
FIG. 3 Example of Test Stack Emulating an Embedded Position Within an Insulated Wall Cavity, Side View
NOTE 1—Drawing not to scale, heat flux transducer size exaggerated relative to hot box dimensions.
FIG. 4 Example of a Test Stack for a Surface-Mounted Heat Flux Transducer
C1130 − 07 (2012)
6.2.1 Forsurface-mountedheatfluxtransducerstestedusing 8.1.3 The test stack composition, including the location of
Test Method C1363, also control the convection and radiation theheatfluxtransducer,thematerialusedtomaskorembedthe
conditions to match the expected application. heat flux transducer, and any additional layers of material used
in the assembly.
6.3 Care shall be taken to perform these tests at heat fluxes
NOTE 7—A diagram of the test stack is suggested.
that are large enough to limit errors due to the readout
electronics and that are similar to the anticipated levels of heat 8.1.4 The temperatures of the heat flux transducer and
flux in the end-use experiment. surface plates.
8.1.5 The heat flux transducer sensitivity and/or calibration
6.4 Ensure that the test stack has reached a steady state
factor. When multiple data points are available, provide corre-
condition before taking data, including the voltage output from
lations and R values.
the heat flux transducer leads. This may require a longer
8.1.6 If known, provide the apparatus clamping pressure.
settling time than is typical for these test methods.
NOTE 5—Theoretically, the output of the heat flux transducer is zero 9. Precision and Bias
when there is no heat flux through the transducer. Eq 1 and 2 are based
9.1 Precision data from one laboratory using Test Method
upon this assumption. For a more rigorous check of heat flux transducer
C177 are given in Table 1 for two sizes of heat flux transducers
response, the user is referred to Appendix X1 which requires that the user
having coplanar copper-constantan thermoelectric junctions in
flip the heat flux transducer over and repeat the test at the same
temperature conditions. A simpler approach that has been used to check
a glass-fiber reinforced epoxy substrate. The repeatability
this assumption is to enclose the heat flux transducer within heavy
standard deviations were determined by pooling replicate data
insulation and place the heat flux transducer and insulation within a
and weighting with their respective degrees of freedoms (10).
temperature-stable environment for 24 h before checking that the output
voltage is indeed zero under conditions of no heat flux.
9.2 Bias—No information can be presented on the bias of
the procedure in Practice C1130 for calibrating thin heat flux
7. Calculation
transducers because no transducer having an accepted refer-
ence value is available.
7.1 For a single-point calibration, use the measured heat
9.3 After the heat flux transducers are calibrated, they are
flux, q, and voltage, E to calculate the sensitivity, depending
used to measure heat flux in a
...

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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 envelope 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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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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5.1.2 This test method provides a means for comparative periodic testing of low emittance surfaces in the field. In this way the effects of aging on the reflective properties can be monitored.  
5.1.3 This test method determines the total hemispherical emittance with a precision of better than ±0.02 units.(1) The emittances of the calibration standards shall have been obtained from accurate independent measurements of total hemispherical emittance. This test method shall not be used for specimens that are highly anisotropic or transparent to infrared radiation. This test method also shall not be used for specimens with significant thermal resistance (see 7.3.4).  
5.1.4 Once a reliable emittance measurement has been determined, the value is available to be used to calculate radiative heat flow from the subject surface. For example, if the temperature of the surface, T1, and the temperature of the surroundings, T2, are known, then the radiative heat flow, Qrad, is given by:
where A is the area of the surface, and either A is assumed to be much smaller than the area of the surroundings or the emittance of the surroundings is assumed to be unity. This radiative heat flow when combined with convective and conductive heat flows provides the total heat flow from the surface (a method for calculating total heat flow is described in Practic...
SCOPE
1.1 This test method covers a technique for determination of the emittance of opaque and highly thermally conductive materials using a portable differential thermopile emissometer. The purpose of the test method is to provide a comparative means of quantifying the emittance of materials near room temperature.  
1.2 This test method does not supplant Test Method C835, which is an absolute method for determination of total hemispherical emittance, or Test Method E408, which includes two comparative methods for determination of total normal emittance. Because of the unique construction of the portable emissometer, it can be calibrated to measure the total hemispherical emittance. This is supported by comparison of emissometer measurements with those of Test Method C835 (1).2  
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.  
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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ASTM
ASTM C1784-20(Test Method)
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 specimens, are not necessarily representative of the relationship between temperature and enthalpy of full-scale PCM products due to the specimen 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 cont...
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 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.  
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.  ...

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ASTM
ASTM C1045-19(Practice)
Standard Practice for Calculating Thermal Transmission Properties Under Steady-State Conditions

SIGNIFICANCE AND USE
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.  
4.2 This practice is intended to provide the user with a uniform procedure for calculating the thermal transmission properties of a material or system from standard test methods used to determine heat flux and surface temperatures. This practice is intended to eliminate the need for similar calculation sections in the ASTM Test Methods (C177, C335, C518, C1033, C1114, C1199, and C1363) by permitting use of these standard calculation forms by reference.  
4.3 This practice provides the method for developing the thermal conductivity as a function of temperature for a specimen from data taken at small or large temperature differences. This relationship can be used to characterize material for comparison to material specifications and for use in calculations programs such as Practice C680.  
4.4 Two general solutions to the problem of establishing thermal transmission properties for application to end-use conditions are outlined in Practice C1058. (Practice C1058 should be reviewed prior to use of this practice.) One is to measure each product at each end-use condition. This solution is rather straightforward, but burdensome, and needs no other elaboration. The second is to measure each product over the entire temperature range of application conditions and to use these data to establish the thermal transmission property dependencies at the various end-use conditions. One advantage of the second approach is that once these dependencies have been established, they serve as the basis for estimating the performance for a given product at othe...
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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.  
1.4 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 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.  
1.6 This practice is not intended to cover all possible aspects of thermal properties data base development. For new materials, the user should investigate the variations in thermal properties seen in similar materials. The information contained in Section 7, the Appendix and the technical papers listed in the References secti...

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ASTM
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:  
5.5.1 Product development and quality control applications.  
5.5.2 Measurement of thermal conductivity at desired mean temperatures.  
5.5.3 Thermal properties of specimens that are moist or close to melting point or other critical tempe...
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.  
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.  
1.4.4 Test Method C177 describes tests that can help ascertain whether conditions of 1.4 are satisfied. For the purposes of this test method, differences in the measurements of less than 2 % may be considered insignificant, and the requirements fulfilled.  
1.5 The specimens shall meet one of the following requirements, in addition to those of 1.4.  
1.5.1 If homogeneous material...

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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
ASTM E2781-24(Practice)
Standard Practice for Evaluation of Methods for Determination of Kinetic Parameters by Calorimetry and Differential Scanning Calorimetry

SIGNIFICANCE AND USE
5.1 The kinetic parameters provided in this practice may be used to evaluate the performance of a standard, apparatus, technique, or software for the determination parameters (such as Test Methods E698, E1641, E2041, or E2070) using thermal analysis techniques such as differential scanning calorimetry, and accelerating rate calorimetry (Guide E1981). The results obtained may be compared to the values provided by this practice.
Note 4: Not all reference materials are suitable for each measurement technique.
SCOPE
1.1 The purpose of this practice is to provide kinetic parameters for reference materials used to evaluate thermal analysis methods, apparatus, and software where enthalpy and temperature are measured. This practice addresses both exothermic and endothermic, nth order, and autocatalytic reactions.  
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.3 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.  
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 F2625-24(Test Method)
Standard Test Method for Measurement of Enthalpy of Fusion, Percent Crystallinity, and Melting Point of Ultra-High Molecular Weight Polyethylene by Means of Differential Scanning Calorimetry

SIGNIFICANCE AND USE
5.1 The crystallinity of UHMWPE will influence its mechanical properties, such as creep and stiffness. The reported crystallinity will depend on the integration range used to determine the heat of fusion, and the theoretical heat of fusion of 100 % crystalline polyethylene used to calculate the percent crystallinity in an unknown specimen. Differential scanning calorimetry is an effective means of accurately measuring both heat of fusion and melting temperature.  
5.2 This test method is useful for both process control and research.
SCOPE
1.1 This quantitative test method discusses the measurement of the heat of fusion and the melting point of ultra-high molecular weight polyethylene (UHMWPE), and the subsequent calculation of the percentage of crystallinity. The method uses a differential scanning calorimeter and can be performed in the laboratory or in the field.  
1.2 This test method can be used for UHMWPE in powder form, consolidated form, finished product, or a used product. It can also be used for irradiated or chemically crosslinked UHMWPE.  
1.3 This test method does not suggest a desired range of crystallinity or melting points for specific applications.  
1.4 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 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.  
1.6 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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