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ASTM E457-08(2020)

(Test Method)

Standard Test Method for Measuring Heat-Transfer Rate Using a Thermal Capacitance (Slug) Calorimeter

Standard Test Method for Measuring Heat-Transfer Rate Using a Thermal Capacitance (Slug) Calorimeter

SIGNIFICANCE AND USE
4.1 The purpose of this test method is to measure the rate of thermal energy per unit area transferred into a known piece of material (slug) for purposes of calibrating the thermal environment into which test specimens are placed for evaluation. The calorimeter and holder size and shape should be identical to that of the test specimen. In this manner, the measured heat transfer rate to the calorimeter can be related to that experienced by the test specimen.  
4.2 The slug calorimeter is one of many calorimeter concepts used to measure heat transfer rate. This type of calorimeter is simple to fabricate, inexpensive, and readily installed since it is not water-cooled. The primary disadvantages are its short lifetime and relatively long cool-down time after exposure to the thermal environment. In measuring the heat transfer rate to the calorimeter, accurate measurement of the rate of rise in back-face temperature is imperative.  
4.3 In the evaluation of high-temperature materials, slug calorimeters are used to measure the heat transfer rate on various parts of the instrumented models, since heat transfer rate is one of the important parameters in evaluating the performance of ablative materials.  
4.4 Regardless of the source of thermal energy to the calorimeter (radiative, convective, or a combination thereof) the measurement is averaged over the calorimeter surface. If a significant percentage of the total thermal energy is radiative, consideration should be given to the emissivity of the slug surface. If non-uniformities exist in the input energy, the heat transfer rate calorimeter would tend to average these variations; therefore, the size of the sensing element (that is, the slug) should be limited to small diameters in order to measure local heat transfer rate values. Where large ablative samples are to be tested, it is recommended that a number of calorimeters be incorporated in the body of the test specimen such that a heat transfer rate distribution across...
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1.1 This test method describes the measurement of heat transfer rate using a thermal capacitance-type calorimeter which assumes one-dimensional heat conduction into a cylindrical piece of material (slug) with known physical properties.  
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
Note 1: For information see Test Methods E285, E422, E458, E459, and E511.  
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.

General Information

Status
Published
Publication Date
31-Oct-2020
ICS
17.200.10 - Heat. Calorimetry
Technical Committee
E21 - Space Simulation and Applications of Space Technology
Drafting Committee
E21.08 - Thermal Protection
Current Stage
Ref Project

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ASTM E457-08(2020) - Standard Test Method for Measuring Heat-Transfer Rate Using a Thermal Capacitance (Slug) CalorimeterASTM E457-08(2020) - Standard Test Method for Measuring Heat-Transfer Rate Using a Thermal Capacitance (Slug) Calorimeter
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ASTM E457-08(2020) - Standard Test Method for Measuring Heat-Transfer Rate Using a Thermal Capacitance (Slug) Calorimeter
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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.
Designation: E457 − 08 (Reapproved 2020)
Standard Test Method for
Measuring Heat-Transfer Rate Using a Thermal Capacitance
1
(Slug) Calorimeter
This standard is issued under the fixed designation E457; 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 (´) indicates an editorial change since the last revision or reapproval.
1. Scope E458Test Method for Heat of Ablation
E459Test Method for Measuring Heat Transfer Rate Using
1.1 This test method describes the measurement of heat
a Thin-Skin Calorimeter
transfer rate using a thermal capacitance-type calorimeter
E511TestMethodforMeasuringHeatFluxUsingaCopper-
which assumes one-dimensional heat conduction into a cylin-
Constantan Circular Foil, Heat-Flux Transducer
drical piece of material (slug) with known physical properties.
1.2 The values stated in SI units are to be regarded as
3. Summary of Test Method
standard. No other units of measurement are included in this
3.1 The measurement of heat transfer rate to a slug or
standard.
thermal capacitance type calorimeter may be determined from
NOTE 1—For information see Test Methods E285, E422, E458, E459,
the following data:
and E511.
3.1.1 Density and specific heat of the slug material,
1.3 This standard does not purport to address all of the
3.1.2 Length or axial distance from the front face of the
safety concerns, if any, associated with its use. It is the
cylindrical slug to the back-face thermocouple,
responsibility of the user of this standard to establish appro-
3.1.3 Slope of the temperature—time curve generated by
priate safety, health, and environmental practices and deter-
the back-face thermocouple, and
mine the applicability of regulatory limitations prior to use.
3.1.4 Calorimeter temperature history.
1.4 This international standard was developed in accor-
3.2 The heat transfer rate is thus determined numerically by
dance with internationally recognized principles on standard-
multiplyingthedensity,specificheat,andlengthoftheslugby
ization established in the Decision on Principles for the
the slope of the temperature–time curve obtained by the data
Development of International Standards, Guides and Recom-
acquisition system (see Eq 1).
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
3.3 The technique for measuring heat transfer rate by the
thermal capacitance method is illustrated schematically in Fig.
2. Referenced Documents
1.Theapparatusshownisatypicalslugcalorimeterwhich,for
2
2.1 ASTM Standards:
example, can be used to determine both stagnation region heat
E285Test Method for Oxyacetylene Ablation Testing of
transfer rate and side-wall or afterbody heat transfer rate
Thermal Insulation Materials
values.Theannularinsulatorservesthepurposeofminimizing
E422Test Method for Measuring Heat Flux Using a Water-
heat transfer to or from the body of the calorimeter, thus
Cooled Calorimeter
approximating one-dimensional heat flow. The body of the
calorimeter is configured to establish flow and should have the
same size and shape as that used for ablation models or test
1
This test method is under the jurisdiction of ASTM Committee E21 on Space
specimens.
Simulation andApplications of SpaceTechnology and is the direct responsibility of
Subcommittee E21.08 on Thermal Protection. 3.3.1 For the control volume specified in this test method, a
Current edition approved Nov. 1, 2020. Published December 2020. Originally
thermal energy balance during the period of initial linear
approvedin1972.Lastpreviouseditionapprovedin2015asE457–08(2015).DOI:
temperatureresponsewhereheatlossesareassumednegligible
10.1520/E0457-08R20.
2
can be stated as follows:
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
EnergyReceivedbytheCalorimeter frontface
~ !
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. 5EnergyConductedAxiallyIntotheSlug
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
E457 − 08 (2020)
FIG. 1 Schematic of a Thermal Capacitance (Slug) Calorimeter
q 5 ρC l ∆T/∆τ 5 MC /A ∆T/∆τ (1) where:
~ ! ~ !~ !
c p p
k = thermal conductivity of slug material, W/m·K
where:
q = q that would be measured at the back-face of the
2
indicated
q˙ = calorimeter heat transfer rate, W/m ,
2
c
slug by Eq 1, W/m
3
ρ = density of slug material, kg/m
...

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Standard Test Method for Measuring Heat Transfer Rate Using a Thin-Skin Calorimeter

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5.1 This test method may be used to measure the net heat transfer rate to a metallic or coated metallic surface for a variety of applications, including:  
5.1.1 Measurements of aerodynamic heating when the calorimeter is placed into a flow environment, such as a wind tunnel or an arc jet; the calorimeters can be designed to have the same size and shape as the actual test specimens to minimize heat transfer corrections;  
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1.2 Advantages:  
1.2.1 Simplicity of Construction—The calorimeter may be constructed from a number of materials. The size and shape can often be made to match the actual application. Thermocouples may be attached to the metal by spot, electron beam, or laser welding.  
1.2.2 Heat transfer rate distributions may be obtained if metals with low thermal conductivity, such as some stainless steels or Inconel 600, are used.  
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5.1 The purpose of this test method is to measure extremely high heat-transfer rates to a body immersed in either a static environment or in a high velocity fluid stream. This is usually accomplished while preserving the structural integrity of the measurement device for multiple exposures during the measurement period. Heat-transfer rates ranging up to 2.84 × 102 MW/m2 (2.5 × 104 Btu/ft2-sec) (7) have been measured using null-point calorimeters. Use of copper null-point calorimeters provides a measuring system with good response time and maximum run time to sensor burnout (or ablation). Null-point calorimeters are normally made with sensor body diameters of 2.36 mm (0.093 in.) press-fitted into the nose of an axisymmetric model.  
5.2 Sources of error involving the null-point calorimeter in high heat-flux measurement applications are extensively discussed in Refs (3-7). In particular, it has been shown both analytically and experimentally that the thickness of the copper above the null-point cavity is critical. If the thickness is too great, the time response of the instrument will not be fast enough to pick up important flow characteristics. On the other hand, if the thickness is too small, the null-point calorimeter will indicate significantly larger (and time dependent) values than the input or incident heat flux. Therefore, all null-point calorimeters should be experimentally checked for proper time response and calibration before they are used. Although a calibration apparatus is not very difficult or expensive to fabricate, there is only one known system presently in existence (6 and 7). The design of null-point calorimeters can be accomplished from the data in this documentation. However, fabrication of these sensors is a difficult task. Since there is not presently a significant market for null-point calorimeters, commercial sources of these sensors are few. Fabrication details are generally regarded as proprietary information. Some users have developed me...
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5.2 This test method is useful for research, quality control, and specification acceptance.
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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 ISO standards 11357–2 is equivalent to this standard.  
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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.7 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 E2603-15(2023)(Practice)
Standard Practice for Calibration of Fixed-Cell Differential Scanning Calorimeters

SIGNIFICANCE AND USE
5.1 Fixed-cell differential scanning calorimeters are used to determine the transition temperatures and energetics of materials in solution. For this information to be accepted with confidence in an absolute sense, temperature and heat calibration of the apparatus or comparison of the resulting data to that of known standard materials is required.  
5.2 This practice is useful in calibrating the temperature and heat flow axes of fixed-cell differential scanning calorimeters.
SCOPE
1.1 This practice covers the calibration of fixed-cell differential scanning calorimeters over the temperature range from –10 °C to +120 °C.  
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. Specific precautionary statements are given in Section 7.  
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 C1702-23(Test Method)
Standard Test Method for Measurement of Heat of Hydration of Hydraulic Cementitious Materials Using Isothermal Conduction Calorimetry

SIGNIFICANCE AND USE
5.1 This method is suitable for determining the total heat of hydration of hydraulic cement at constant temperature at ages up to 7 days to confirm specification compliance.  
5.2 This method compliments Practice C1679 by providing details of calorimeter equipment, calibration, and operation. Practice C1679 emphasizes interpretation significant events in cement hydration by analysis of time dependent patterns of heat flow, but does not provide the level of detail necessary to give precision test results at specific test ages required for specification compliance.
SCOPE
1.1 This test method specifies the apparatus and procedure for determining total heat of hydration of hydraulic cementitious materials at test ages up to 7 days by isothermal conduction calorimetry.  
1.2 This test method also outputs data on rate of heat of hydration versus time that is useful for other analytical purposes, as covered in Practice C1679.  
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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  • Standard
    8 pages
    English language
    sale 15% off