1、Designation: C1130 07 (Reapproved 2012)Standard Practice forCalibrating Thin Heat Flux Transducers1This standard is issued under the fixed designation C1130; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision
2、. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice, in conjunction with Test Method C177,C518, C1114,orC1363, establishes an experimental procedurefor determining the s
3、ensitivity of heat flux transducers that arerelatively thin.1.1.1 For the purpose of this standard, the thickness of theheat flux transducer shall be less than 30 % of the narrowestplanar dimension of the heat flux transducer.1.2 This practice discusses a method for determining thesensitivity of a h
4、eat flux transducer to one-dimensional heatflow normal to the surface and for determining the sensitivityof a heat flux transducer for an installed application.1.3 This practice should be used in conjunction with Prac-tice C1046 when performing in-situ measurements of heat fluxon opaque building com
5、ponents.1.4 This practice is not intended to determine the sensitivityof heat flux transducers that are components of heat flow meterapparatus, as in Test Method C518.1.5 This practice is not intended to determine the sensitivityof heat flux transducers used for in-situ industrial applicationsthat a
6、re covered in Practice C1041.1.6 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations
7、 prior to use.2. Referenced Documents2.1 ASTM Standards:2C168 Terminology Relating to Thermal InsulationC177 Test Method for Steady-State Heat Flux Measure-ments and Thermal Transmission Properties by Means ofthe Guarded-Hot-Plate ApparatusC518 Test Method for Steady-State Thermal TransmissionProper
8、ties by Means of the Heat Flow Meter ApparatusC1041 Practice for In-Situ Measurements of Heat Flux inIndustrial Thermal Insulation Using Heat Flux Transduc-ersC1044 Practice for Using a Guarded-Hot-Plate Apparatus orThin-Heater Apparatus in the Single-Sided ModeC1046 Practice for In-Situ Measurement
9、 of Heat Flux andTemperature on Building Envelope ComponentsC1114 Test Method for Steady-State Thermal TransmissionProperties by Means of the Thin-Heater ApparatusC1155 Practice for Determining Thermal Resistance ofBuilding Envelope Components from the In-Situ DataC1363 Test Method for Thermal Perfo
10、rmance of BuildingMaterials and Envelope Assemblies by Means of a HotBox Apparatus3. Terminology3.1 DefinitionsFor definitions of terms relating to thermalinsulating materials, see Terminology C168.3.2 Definitions of Terms Specific to This Standard:3.2.1 maskmaterial (or materials) having the same,
11、ornearly the same, thermal properties and thickness surroundingthe heat flux transducer thereby promoting one-dimensionalheat flow through the heat flux transducer.3.2.2 sensitivitythe ratio of the electrical output of the heatflux transducer to the heat flux passing through the devicewhen measured
12、under steady-state heat flow.3.2.3 test stacka layer or a series of layers of material puttogether to comprise a test sample (for example, a roof systemcontaining a membrane, an insulation, and a roof deck).3.3 Symbols:R = thermal resistance, m2K/W (hft2F /Btu)q = heat flux, W/m2(Btu/hft2)Qexpected=
13、 heat flux expected in application, W/m2(Btu/hft2)E = measured output voltage, VS = sensitivity, V/(W/m2) (V/(Btu/hrft2)T = temperature difference, K (F)Rlayer= thermal resistance of a layer in the test stack,m2K/W (hft2F /Btu)T = temperature, K (F)1This practice is under the jurisdiction of ASTM Co
14、mmittee C16 on ThermalInsulation and is the direct responsibility of Subcommittee C16.30 on ThermalMeasurement.Current edition approved Sept. 1, 2012. Published November 2012. Originallyapproved in 1989. Last previous edition approved in 2007 as C1130 07. DOI:10.1520/C1130-07R12.2For referenced ASTM
15、 standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohock
16、en, PA 19428-2959. United States1uc= combined standard uncertaintyu1= standard uncertainty of the regression coefficientsu2= standard uncertainty for replicate measurementsu3= standard uncertainty for the measurement = error term4. Significance and Use4.1 The use of heat flux transducers on building
17、 envelopecomponents provides the user with a means for performingin-situ heat flux measurements.Accurate translation of the heatflux transducer output requires a complete understanding of thefactors affecting its output, and a standardized method fordetermining the heat flux transducer sensitivity f
18、or the appli-cation of interest.4.2 The sensitivity of the heat flux transducer is determinedprimarily by the sensor construction and temperature of opera-tion and the details of the application, including geometry,material characteristics, and environmental factors.NOTE 1Practice C1046 includes an
19、excellent description of heat fluxtransducer construction.4.3 The presence of a heat flux transducer is likely to alterthe heat flux that is being measured. To determine the heat flowthat would occur in the absence of the transducer, it isnecessary to either:4.3.1 Ensure that the installation is ade
20、quately guarded (1).34.3.2 Adjust the results based on a detailed model ornumerical analysis. Such analysis is beyond the scope of thispractice, but details can be found in (2-6).4.3.3 Use the empirically measured heat flux transducersensitivity measured under conditions that adequately simulatethe
21、conditions of use in the final application.4.4 There are several methods for determining the sensitiv-ity of heat flux transducers, including Test Methods C177,C518, C1114, and C1363. The selection of the appropriateprocedure will depend on the required accuracy and thephysical limitations of availa
22、ble equipment.4.5 This practice describes techniques to establish uniformheat flow normal to the heat flux transducer for the determi-nation of the heat flux transducer sensitivity.4.6 The method of heat flux transducer application must beadequately simulated or duplicated when experimentally deter-
23、mining the heat flux transducer sensitivity. The two mostwidely used application techniques are to surface-mount theheat flux transducer or to embed the heat flux transducer in theinsulation system.NOTE 2The difference between the sensitivity under uniform normalheat flow versus that for the surface
24、-mounted or embedded configurationshas been demonstrated using multiple mathematical techniques (7-9).5. Specimen Preparation5.1 Specimen Preparation for All Cases:5.1.1 Check the electrical continuity of the heat flux trans-ducer. Connect the heat flux transducer voltage leads to theauxiliary measu
25、rement equipment (for example, voltmeter)having a resolution of 6 2 V or better.5.1.2 When bringing the heat flux transducer voltage leadsout of the test instrument, take care to avoid air gaps in themask or between the sample stack and the test instrument. Fillair gaps with a conformable material,
26、such as toothpaste, caulk,or putty, or cover with tape.NOTE 3The heat flux transducers do not need to be physically adheredto the mask or embedding material but should fit well enough to assuregood thermal contact. If needed, apply thermally conductive gel to one orboth faces of the heat flux transd
27、ucer to improve the thermal contact.Material compatibility must be considered in the selection of any such gel.5.1.3 Place a temperature sensor on or near the heat fluxtransducer. Connect temperature sensor(s) applied to the heatflux transducer to a readout device.5.1.4 When compressible insulation
28、is included in the teststack, manually control the distance between the hot and coldapparatus surfaces.5.1.5 The heat flux transducer(s) must be located within themetered area of the apparatus. In a hot box apparatus, mountthe heat flux transducers in the central portion of the meteredarea of the te
29、st panel.5.2 Three separate test stack preparations are discussed todetermine appropriately: the one-dimensional sensitivity, thesensitivity for embedded configurations, and the sensitivity forsurface-mounted configurations.5.3 One-Dimensional SensitivityThe heat flux transducershall be embedded in
30、a test stack and surrounded with a mask,as shown in Fig. 1.5.3.1 The test stack shall consist of a sandwich of the heatflux transducer/masking layer between two layers of a com-pressible homogeneous material, such as high-density fibrousglass insulation board, to assure good thermal contact betweent
31、he plates of the tester and the heat flux transducer/maskinglayer.5.3.2 The mask must have the same thickness and thermalresistance as the heat flux transducer.5.3.3 The mask or embedding material should be signifi-cantly larger than the metering area of the test equipment andideally be the same siz
32、e as the plates of the apparatus.5.3.4 To measure the sensitivity of multiple small heat fluxtransducers, the heat flux transducer/mask layer shown in Fig.1 is replaced with a layer containing an arrangement oftransducers located within the metered area of the apparatus asillustrated in Fig. 2.5.4 S
33、ensitivity, Embedded ConfigurationPlace the heatflux transducer, in a fashion identical to its end use application,in a test stack duplicating the building construction to beevaluated. An example of a test stack, for the case where theheat flux transducer is to be embedded in gypsum wallboardfacing
34、an insulated wall cavity, is shown in Fig. 3.5.5 Sensitivity, Surface-Mounted ConfigurationApply theheat flux transducer in a manner identical to that of actual useas specified in Practice C1046. Important considerations forsurface mounting include thermal contact between the heat fluxtransducer and
35、 the surface and matching of the emittance of theheat flux transducer and test construction. An example of a testarrangement, for the case where the heat flux transducer is tobe surface-mounted, is shown in Fig. 4.3The boldface numbers in parentheses refer to the references at the end of thisstandar
36、d.C1130 07 (2012)2NOTE 4In many cases, several surface-mounted heat flux transducerswill be used at one time and can be analyzed for sensitivity simultane-ously.6. Procedure6.1 Use a guarded-hot-plate, heat flow meter, hot box, orthin-heater apparatus. Follow Test Method C177, C518,C1363,orC1114, in
37、cluding test stack conditioning, to measurethe heat flux through the heat flux transducer. Apparatuses thattypically require two samples should be operated in thesingle-sided mode in conformance with Practice C1044.6.2 Vary the hot- and cold-surface plates of the test instru-ment to produce the rang
38、e of heat fluxes and mean tempera-tures according to the guidance found in Appendix X1 andAppendix X2.FIG. 1 Example of a Test Stack Used to Measure Heat Flux Transducer Sensitivity, Side ViewNOTE 1Some apparatus metering areas are round.FIG. 2 Top View of the Heat Flux Transducer/Mask Layer Within
39、the Test Stack for the Case Where Multiple Small Heat Flux Transduc-ers are Evaluated SimultaneouslyC1130 07 (2012)3FIG. 3 Example of Test Stack Emulating an Embedded Position Within an Insulated Wall Cavity, Side ViewNOTE 1Drawing not to scale, heat flux transducer size exaggerated relative to hot
40、box dimensions.FIG. 4 Example of a Test Stack for a Surface-Mounted Heat Flux TransducerC1130 07 (2012)46.2.1 For surface-mounted heat flux transducers tested usingTest Method C1363, also control the convection and radiationconditions to match the expected application.6.3 Care shall be taken to perf
41、orm these tests at heat fluxesthat are large enough to limit errors due to the readoutelectronics and that are similar to the anticipated levels of heatflux in the end-use experiment.6.4 Ensure that the test stack has reached a steady statecondition before taking data, including the voltage output f
42、romthe heat flux transducer leads. This may require a longersettling time than is typical for these test methods.NOTE 5Theoretically, the output of the heat flux transducer is zerowhen there is no heat flux through the transducer. Eq 1 and 2 are basedupon this assumption. For a more rigorous check o
43、f heat flux transducerresponse, the user is referred to Appendix X1 which requires that the userflip the heat flux transducer over and repeat the test at the sametemperature conditions. A simpler approach that has been used to checkthis assumption is to enclose the heat flux transducer within heavyi
44、nsulation and place the heat flux transducer and insulation within atemperature-stable environment for 24 h before checking that the outputvoltage is indeed zero under conditions of no heat flux.7. Calculation7.1 For a single-point calibration, use the measured heatflux, q, and voltage, E to calcula
45、te the sensitivity, dependingupon the test stack chosen, as shown in Eq 1.S 5Eq(1)7.2 When multiple data points are available, evaluate thedata using the selected model as discussed in Appendix X1.7.3 An example of a least square linear fit of sensitivity asa function of temperature is shown in Fig.
46、 5. Alternativemodels and data analysis are discussed in Appendix X1.NOTE 6Do not confuse calibration terminology in this practice withthat in other C16 application standards. For example, Practice C1046 usesthe term “conversion factor” (which also is designated S and has units of(W/m2) per V) to re
47、late the measured HFT output to the flux through thebuilding envelope. This practice advocates using the following form (Eq2) for applications of heat flux transducers:q 5ES(2)8. Report8.1 Report the following information:8.1.1 The heat flux transducer manufacturer, modelidentification, size, thickn
48、ess, geometry (that is, square orround), and dimensions.8.1.2 The ASTM Test Method used and the size of theapparatus plates.8.1.3 The test stack composition, including the location ofthe heat flux transducer, the material used to mask or embed theheat flux transducer, and any additional layers of ma
49、terial usedin the assembly.NOTE 7A diagram of the test stack is suggested.8.1.4 The temperatures of the heat flux transducer andsurface plates.8.1.5 The heat flux transducer sensitivity and/or calibrationfactor. When multiple data points are available, provide corre-lations and R2values.8.1.6 If known, provide the apparatus clamping pressure.9. Precision and Bias9.1 Precision data from one laboratory using Test MethodC177 are given in Table 1 for two sizes of heat flux transducershaving coplanar copper-constantan thermoelectric junctions ina glass-
