EN ISO 22007-6-2015 en Plastics - Determination of thermal conductivity and thermal diffusivity - Part 6 Comparative method for low thermal conductivities using a temperature-modul.pdf

1、BSI Standards PublicationPlastics Determination of thermal conductivity and thermal diffusivityPart 6: Comparative method for low thermal conductivities using a temperature-modulation techniqueBS EN ISO 22007-6:2015BS EN ISO 22007-6:2015National forewordThis British Standard is the UK implementation

2、 of EN ISO 22007-6:2015. It is identical to ISO 22007-6:2014. It supersedes BS ISO 22007-6:2014, which is withdrawn.The UK participation in its preparation was entrusted to Technical Committee PRI/21, Testing of plastics.A list of organizations represented on this committee can be obtained on reques

3、t to its secretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2015. Published by BSI Standards Limited 2015ISBN 978 0 580 87283 9ICS 83.080.01Compliance with a British S

4、tandard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 May 2014.Amendments/corrigenda issued since publicationDate Text affected30 April 2015 This corrigendum renumbers BS ISO 22007-6:2014 as B

5、S EN ISO 22007-6:2015BRITISH STANDARDEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 22007-6 March 2015 ICS 83.080.01 English Version Plastics - Determination of thermal conductivity and thermal diffusivity - Part 6: Comparative method for low thermal conductivities using a temperature-modu

6、lation technique (ISO 22007-6:2014) Plastiques - Dtermination de la conductivit thermique et de la diffusivit thermique - Partie 6: Mthode comparative pour faibles conductivits thermiques utilisant une technique de modulation de la temprature (ISO 22007-6:2014) Kunststoffe - Bestimmung der Wrmeleitf

7、higkeit und der Temperaturleitfhigkeit - Teil 6: Vergleichsmethoden fr geringe Wrmeleitfhigkeit unter Anwendung einer Temperaturanpassungsmethode (ISO 22007-6:2014) This European Standard was approved by CEN on 12 March 2015. CEN members are bound to comply with the CEN/CENELEC Internal Regulations

8、which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member. This

9、 European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CEN membe

10、rs are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portuga

11、l, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2015 CEN All rights of exploitation in any form

12、 and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 22007-6:2015 EForeword The text of ISO 22007-6:2014 has been prepared by Technical Committee ISO/TC 61 “Plastics” of the International Organization for Standardization (ISO) and has been taken over as EN ISO 22007-6:2015

13、by Technical Committee CEN/TC 249 “Plastics” the secretariat of which is held by NBN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by September 2015, and conflicting national standards shall be wi

14、thdrawn at the latest by September 2015 Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. According to the CEN-CENELEC Internal Regulati

15、ons, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy

16、, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. Endorsement notice The text of ISO 22007-6:2014 has been approved by CEN as EN ISO 22007-6:2015 without any modification. BS EN ISO 2

17、2007-6:2015 EN ISO 22007-6:2015 (E)ii ISO 2014 All rights reserved ISO 2014 All rights reserved iiiContents PageForeword iIntroduction 1 Scope . 12 Normative references 13 Terms and definitions . 24 Principle 35 Apparatus . 46 Test specimens 56.1 Measuring temperature. 56.2 Geometry of the probe mat

18、erial . 56.3 Specimen area size 66.4 Specimen thickness . 67 Procedure. 68 Expression of results 68.1 Graphical presentation . 68.2 Verification . 79 Test report . 7Annex A (informative) Results of thermal conductivity of cellular plastics 9Annex B (informative) Infinite thickness 11Bibliography .12

19、iviBS EN ISO 22007-6:2015 ISO 22007-6:2014 (E)iv ISO 2014 All rights reservedIntroductionThermal insulating properties have become more important in view of power-saving technology. The method which is applicable to measure the lower thermal conductivity in smaller scale with a small amount of a spe

20、cimen, such as a tray for food, a thermal printing film, a gelled sheet for the electric parts inside laptop PC, an adhesive paste, etc., is required for the micro-scale thermal design of plastics. A double-sensor system of high-sensitivity thermopile located in the different distances in the modula

21、ted temperature field, which is controlled by the Peltier thermo-module, is proposed for the determination of thermal conductivity of plastics. A decay parameter is utilized to determine the thermal conductivity of the sample. This method is applied to the measurement of low thermal conductivity in

22、the range below 1,0 W/mK.In contrast to a pulse or a transient method, high sensitivity and high-temperature resolution are characteristic of temperature modulated technique, in which employment of a lock-in amplifier reduces any influence of noise and interference.The thermal conductivity of materi

23、als that are poor conductors of heat is usually determined by measuring the larger temperature gradients in the sample produced by a steady flow of heat in one-dimensional geometry. In order to reduce the errors of radiation and convection, it often requires large, precisely shaped samples and extre

24、me care to be used successfully.This part of ISO 22007 specifies a modulated temperature method to determine the thermal conductivity with a small temperature variation, minimizing the influence of radiation and convection.BS EN ISO 22007-6:2015 ISO 22007-6:2014 (E)Plastics Determination of thermal

25、conductivity and thermal diffusivity Part 6: Comparative method for low thermal conductivities using a temperature-modulation technique1 ScopeThis part of ISO 22007 specifies a modulated temperature method realizing the measurement of thermal conductivity. An input of temperature deviation is less t

26、han 1 K, and a double lock-in method is applied to amplify the small temperature modulation.ISO 22007-3 specifies one of the modulated temperature methods where the phase shift is measured in the thermally thick condition, kd 1 k = (/2)1/2, : angular frequency of temperature wave, : thermal diffusiv

27、ity, and d: thickness of the specimen. In this condition, the backing material does not affect on the phase shift results on the sensor, on which temperature wave decays exponentially.On the other hand, if kd 1, the decay of temperature modulation is influenced by the backing materials. Based on thi

28、s principle, this part of ISO 22007 specifies the method to determine the thermal conductivity of the sample (as a backing material), comparing the decay of temperature wave detected on both surfaces of the probe material.Thermal conductivity is determined from the correlation between the thermal im

29、pedance and the decay ratio of amplitude using two reference materials measured at the same frequency and temperature.The covering thermal conductivity range is adjusted with the reference materials and the probe materials. Basically, thermal conductivity is determined in the range from 0,026 W/mK t

30、o 0,6 W/mK.In the case applying the method to inhomogeneous materials, cares must be taken to choose the appropriate measurement conditions in accordance with the thermal penetration depth.2 Normative referencesThe following documents, in whole or in part, are normatively referenced in this document

31、 and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.ISO 472, Plastics VocabularyISO 22007-1, Plastics Determination of thermal conductivity and therm

32、al diffusivity Part 1: General principlesISO 22007-3, Plastics Determination of thermal conductivity and thermal diffusivity Part 3: Temperature wave analysis methodISO/TR 22007-5, Plastics Determination of thermal conductivity and thermal diffusivity Part 5: Results of interlaboratory testing of po

33、ly(methyl methacrylate) samplesISO 80000-5, Quantities and units Part 5: ThermodynamicsINTERNATIONAL STANDARD ISO 22007-6:2014(E) ISO 2014 All rights reserved 1BS EN ISO 22007-6:2015 3 Terms and definitionsFor the purposes of this document, the terms and definitions given in ISO 472, ISO 22007-1, IS

34、O 22007-3, ISO 80000-5, and the following apply.3.1amplitude of temperature modulationAmpamplitude of the temperature oscillation produced by a modulated-power heat sourceNote 1 to entry: It is expressed in Kelvin.3.2gainratio of Amp at x = d to x = 0; amplitude ratio of the front (x = 0) and rear (

35、x = d) surfaces of the probe material =TTAmpAmpdxdx00whereT0and Tdare the amplitude of modulated temperature measured on the sensor 1 (at x = 0) and the sensor 2 (x = d), respectively.3.3thermal penetration depthDpperiodic oscillations in temperature can only be observed for the depths less than Dp,

36、 defined asDp=22piwhere is thermal diffusivity; is angular frequency;Dpis the depth at which the amplitude of the temperature oscillation has been attenuated to 0,19 % as derived from expexp ,=()2200019Dppi .Note 1 to entry: The thermal penetration depth is expressed in metres.3.4thermal diffusion l

37、ength1/kwherek is defined as 2Note 1 to entry: The thermal diffusion length is expressed in metres. k is expressed in reciprocal metres.2 ISO 2014 All rights reservedBS EN ISO 22007-6:2015 ISO 22007-6:2014 (E)4 PrincipleAs depicted in Figure 1, the probe material in a flat sheet shape is set between

38、 the heat source and the sample, assuming the one-dimensional heat flow.The heat source generates a temperature modulation at a constant amplitude, keeping the average temperature constant that is realized by using a thermo-electric type (Peltier type) temperature control. Due to the large heat capa

39、city of the heat sink, the temperature modulation in the heat source is not affected by the sample, and the input temperature (x = 0) on the probe is kept constant.The sample is attached to the other side of the probe material. In the thermally thin condition, kd 1, the decaying temperature modulati

40、on at x = d is influenced by the sample.The modulated temperatures at x = 0 and x = d are precisely measured by the attached temperature sensor, respectively, using a lock-in amplification.The characteristic of the principle is listed as below.a) A small temperature change of the modulated temperatu

41、re, for instance, less than 1 K, is given at a surrounding temperature. The average temperature is kept at a surrounding temperature, using a thermo-electric type (Peltier-type) temperature control.b) The temperature at a bottom of the heat sink (an opposite side from x = 0 in Figure 1), a deep loca

42、tion in the sample (an opposite side from x = d in Figure 1), and the cold-junction of the thermopile sensor, are considered as the surrounding temperature.c) A one-dimensional heat flow is attained, measuring a small area located in the centre of the plane heat flow.d) The frequency for the measure

43、ment is chosen considering the thermal diffusion length of a probe material.e) The lock-in amplification, that is characteristic of the modulation technique, enables to measure the small temperature variation that minimizes the influence of the radiation and convection.Key1 heat sink2 probe material

44、 3 sample4 sensor 15 sensor 26 heater (Peltier module)x direction of sample thicknessFigure 1 Geometry of two sensors and one Peltier heat source ISO 2014 All rights reserved 3BS EN ISO 22007-6:2015 ISO 22007-6:2014 (E)5 ApparatusThe apparatus shall be designed to obtain the gain as defined in 3.2 a

45、nd shall consist of the following main components as shown in Figure 2.5.1 Heat sink, with heat capacity that is so large as to estimate the bottom temperature (on the opposite side from x = 0) at room temperature.5.2 Thermoelectric module and two sensor elements, with the following characteristics.

46、5.2.1 Thermoelectric-module that generates a temperature oscillation by passing alternating current through a Peltier-type heat source attached to the front surface of the probe materials; it is assumed to be located at x = 0 (see Figure 2).5.2.2 Sensor element is a thermopile, of which a cold-junct

47、ion is attached to the surrounding temperature area and a hot-junction located in the mid area detects the temperature variation by the differential amplification.5.2.3 Sensor elements (sensor 1 and sensor 2) are located at x = 0 and x = d, respectively, in order to measure the amplitude of the temp

48、erature oscillation on the front and rear surfaces of the probe material in Figures 2 and 3.5.3 Probe materials, with thermal properties : thermal diffusivity, : thermal conductivity, k: k = (/2)1/2, : angular frequency of temperature wave and thickness, d, is located between the heat source and the

49、 sample (s, s, and ks).123456Key1 heat sink2 Peltier module3 sensor 1 lock-in amplifier 14 probe materials5 sensor 2 lock-in amplifier 26 sampleFigure 2 Schematic diagram of the measuring geometry4 ISO 2014 All rights reservedBS EN ISO 22007-6:2015 ISO 22007-6:2014 (E)t10 12024 68-1011243TacKey1 sensor 12 sensor 23 amplitude 14 amplitude 2Tacmodulated temperature on a sensor in Kt time angular frequency of temperature waveFigure 3 Schematic view of the temperature modulation