1、BSI Standards PublicationBS ISO 9869-1:2014Thermal insulation Building elements In-situ measurement of thermal resistance and thermal transmittancePart 1: Heat flow meter methodBS ISO 9869-1:2014 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of ISO 9869-1:2014. The
2、UK participation in its preparation was entrusted to TechnicalCommittee B/540/8, Mirror committee for ISO/TC 163 - Thermal Performance and Energy use in the built Environment.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not p
3、urport to include all the necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2014.Published by BSI Standards Limited 2014ISBN 978 0 580 82178 3ICS 91.120.10Compliance with a British Standard cannot confer immunity from legal oblig
4、ations.This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 August 2014.Amendments/corrigenda issued since publicationDate T e x t a f f e c t e dBS ISO 9869-1:2014 ISO 2014Thermal insulation Building elements In-situ measurement of thermal res
5、istance and thermal transmittance Part 1: Heat flow meter methodIsolation thermique lments de construction Mesurage in situ de la rsistance thermique et du coefficient de transmission thermique Partie 1: Mthode du fluxmtreINTERNATIONAL STANDARDISO9869-1First edition2014-08-01Reference numberISO 9869
6、-1:2014(E)BS ISO 9869-1:2014ISO 9869-1:2014(E)ii ISO 2014 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2014All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including phot
7、ocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below or ISOs member body in the country of the requester.ISO copyright officeCase postale 56 CH-1211 Geneva 20Tel. + 41 22 749 01 11Fax + 41 22 749 09 47
8、E-mail copyrightiso.orgWeb www.iso.orgPublished in SwitzerlandBS ISO 9869-1:2014ISO 9869-1:2014(E) ISO 2014 All rights reserved iiiContents PageForeword ivIntroduction v1 Scope . 12 Normative references 13 Terms, definitions, symbols and units . 23.1 Terms and definitions . 23.2 Symbols and units 24
9、 Apparatus . 44.1 Heat flow meter (HFM) 44.2 Temperature sensors . 45 Calibration procedure . 55.1 Calibration of the HFM . 55.2 Temperature sensors . 65.3 Measuring equipment . 76 Measurements . 76.1 Installation of the apparatus . 76.2 Data acquisition . 87 Analysis of the data 87.1 Average method
10、 . 87.2 Storage effects . 107.3 Comparison of calculated and measured values .128 Corrections for the thermal resistance and the finite dimension of the HFM .129 Accuracy .1210 Test report 13Annex A (normative) Heat transfer at surfaces and U-value measurement .15Annex B (normative) Dynamic analysis
11、 method .18Annex C (normative) Examination of the structure of the element 23Annex D (informative) Perturbations caused by the heat flow meter 25Annex E (informative) Checking the accuracy of the measurement system of heat flow rate .31Annex F (informative) Heat storage effects .34Bibliography .36BS
12、 ISO 9869-1:2014ISO 9869-1:2014(E)ForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body inte
13、rested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnica
14、l Commission (IEC) on all matters of electrotechnical standardization.The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types of ISO docum
15、ents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsibl
16、e for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents).Any trade name used in this document is information given for t
17、he convenience of users and does not constitute an endorsement.For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the WTO principles in the Technical Barriers to Trade (TBT) see the following URL: F
18、oreword - Supplementary informationThe committee responsible for this document is ISO/TC 163, Thermal performance and energy use in the built environment, Subcommittee SC 1, Test and measurement methods.This first edition cancels and replaces ISO 9869:1994, which has been technically revised.Annexes
19、 A, B and C form an integral part of this part of ISO 9869. Annexes D, E and F are for information only.iv ISO 2014 All rights reservedBS ISO 9869-1:2014ISO 9869-1:2014(E)IntroductionThe thermal transmittance of a building element (U-value) is defined in ISO 7345 as the “Heat flow rate in the steady
20、 state divided by area and by the temperature difference between the surroundings on each side of a system”.In principle, the U-value can be obtained by measuring the heat flow rate through an element with a heat flow meter or a calorimeter, together with the temperatures on both sides of the elemen
21、t under steady-state conditions.However, since steady-state conditions are never encountered on a site in practice, such a simple measurement is not possible. But there are several ways of overcoming this difficulty:a) Imposing steady-state conditions by the use of a hot and a cold box. This method
22、is commonly used in the laboratory (ISO 8990) but is cumbersome in the field;b) Assuming that the mean values of the heat flow rate and temperatures over a sufficiently long period of time give a good estimate of the steady-state. This method is valid if:1) the thermal properties of the materials an
23、d the heat transfer coefficients are constant over the range of temperature fluctuations occurring during the test;2) the change of amount of heat stored in the element is negligible when compared to the amount of heat going through the element. This method is widely used but may lead to long period
24、s of measurement and may give erroneous results in certain cases.c) Using a dynamic theory to take into account the fluctuations of the heat flow rate and temperatures in the analysis of the recorded data.NOTE The temperatures of the surroundings, used in the definition of the U-value, are not preci
25、sely defined in ISO 7345. Their exact definition depends on the subsequent use of the U-value and may be different in different countries (see Annex A). ISO 2014 All rights reserved vBS ISO 9869-1:2014BS ISO 9869-1:2014Thermal insulation Building elements In-situ measurement of thermal resistance an
26、d thermal transmittance Part 1: Heat flow meter method1 ScopeThis part of ISO 9869 describes the heat flow meter method for the measurement of the thermal transmission properties of plane building components, primarily consisting of opaque layers perpendicular to the heat flow and having no signific
27、ant lateral heat flow.The properties which can be measured are:a) the thermal resistance, R, and thermal conductance, , from surface to surface;b) the total thermal resistance, RT, and transmittance from environment to environment, U, if theenvironmental temperatures of both environments are well de
28、fined.The heat flow meter measurement method is also suitable for components consisting of quasi homogeneous layers perpendicular to the heat flow, provided that the dimensions of any inhomogeneity in close proximity to the heat flow meter (HFM) is much smaller than its lateral dimensions and are no
29、t thermal bridges which can be detected by infrared thermography (see 6.1.1).This part of ISO 9869 describes the apparatus to be used, the calibration procedure for the apparatus, the installation and the measurement procedures, the analysis of the data, including the correction of systematic errors
30、 and the reporting format.NOTE 1 It is not intended as a high precision method replacing the laboratory instruments such as hot boxes that are specified in ISO 8990:1994.NOTE 2 For other components, an average thermal transmittance may be obtained using a calorimeter or by averaging the results of s
31、everal heat flow meter measurements.NOTE 3 In building with large heat capacities, the average thermal transmittance of a component can be obtained by measurement over an extended period, or the apparent transmittance of the part can be estimated by a dynamic analysis of its thermal absorption respo
32、nse (see Annex B).2 Normative referencesThe following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (in
33、cluding any amendments) applies.ISO 6781:1983, Thermal insulation Qualitative detection of thermal irregularities in building envelopes Infrared methodISO 6946:2007, Building components and building elements Thermal resistance and thermal transmittance Calculation methodISO 7345:1987, Thermal insula
34、tion Physical quantities and definitionsINTERNATIONAL STANDARD ISO 9869-1:2014(E) ISO 2014 All rights reserved 1BS ISO 9869-1:2014ISO 9869-1:2014(E)ISO 8301:1991, Thermal insulation Determination of steady-state thermal resistance and related properties Heat flow meter apparatusISO 8302:1991, Therma
35、l insulation Determination of steady-state thermal resistance and related properties Guarded hot plate apparatusISO 8990:1994, Thermal insulation Determination of steady-state thermal transmission properties Calibrated and guarded hot box3 Terms, definitions, symbols and units3.1 Terms and definitio
36、nsFor the purpose of this document, the terms and definitions given in ISO 7345:1987 apply.3.2 Symbols and unitsSymbol Quantity UnitR thermal resistance m2K/WRTtotal thermal resistance m2K/WRsiinternal surface thermal resistance m2K/WRseexternal surface thermal resistance m2K/W thermal conductance W
37、/(m2K)U thermal transmittance W/(m2K) heat flow rate WA area m2q density of heat flow rate =/A W/m2Tiinterior environmental (ambient) temperature C or K2 ISO 2014 All rights reservedBS ISO 9869-1:2014ISO 9869-1:2014(E)Symbol Quantity UnitTeexterior environmental (ambient) temperature C or KTsiinteri
38、or surface temperature of the building ele-mentC or KTseexterior surface temperature C or K density of a material kg/m3d thickness of a layer mc specific heat capacity J/(kgK)C thermal capacity of a layer: C=cd J/(m2K)Fi, Fecorrection factors calculated with Formula (8) to take into account the stor
39、age effectsJ/(m2K)E operational error (of an installed HFM) which is the relative error between the measured and the actual heat flow-NOTE The environmental (ambient) temperatures shall correspond with those used in the definition adopted for the U-value (see Annex A).In the steady-state, the therma
40、l properties of the elements have the following definitions:R is the thermal resistance of an element, surface to surface and is given byRTTq=si se1(1)where is the thermal conductance of the building element, surface to surface.U is the thermal transmittance of the element, environment to environmen
41、t and is given byUqTT R=()=ie T1(2)where RTis the total thermal resistance which is given byRRRRTsise=+ (3)where Rsiand Rseare the internal and external surface thermal resistances, respectively.R and RThave units of square metres kelvin per watt (m2K/W); U and have units of watts per square metre k
42、elvin W/(m2K). ISO 2014 All rights reserved 3BS ISO 9869-1:2014ISO 9869-1:2014(E)4 Apparatus4.1 Heat flow meter (HFM)The HFM is a transducer giving an electrical signal which is a direct function of the heat flow transmitted through it.Most HFMs are thin, thermally resistive plates with temperature
43、sensors arranged in such a way that the electrical signal given by the sensors is directly related to the heat flow through the plate (see Figure 1). The essential properties of an HFM are that it should have a low thermal resistance in order to minimize the perturbation caused by the HFM, and a hig
44、h enough sensitivity to give a sufficiently large signal for the lowest heat flow rates measured. Recent HFMs are very thin, with low thermal resistance, and highly sensitive. If the thermal resistance of the HFM is low enough, the effects of perturbation of the surface heat flow by positioning the
45、HFM is negligible. The heat flow rate is influenced by building elements and the difference between indoor and outdoor temperature. Therefore, HFM with an appropriate sensitivity shall be selected in consideration of these influences (see Annex E).NOTE More detailed information on the structure and
46、calibration of HFMs can be found in ISO 8301:1991.4.2 Temperature sensorsTemperature sensors are transducers giving an electrical signal which is a monotonic function of its temperature.The effects of the heat flow going through the sensor and on other physical quantities, such as stresses, electrom
47、agnetic radiation on the signal have to be taken into account (see Clause 5).Suitable surface temperature sensors (for R- or -value measurements) are thin thermocouples and flat resistance thermometers. It is possible, for the conductance measurements, for one or several sensors to be incorporated w
48、ithin one side of the HFM, the side which will be in contact with the surface of the element being measured.Environmental (ambient) temperature sensors (for U-value measurements) shall be chosen according to the temperature to be measured. For example, if the U-value is defined by the ratio of densi
49、ty of heat flow rate to the air temperature difference, air temperature sensors are to be used. These sensors are shielded against solar and thermal radiation and are ventilated. Other sensors may measure the so-called sol-air temperature, the comfort temperature etc. (see Annex A).4 ISO 2014 All rights reservedBS ISO 9869-1:2014ISO 9869-1:2014(E)Dimensions in millimetresKey1 base material 5 upper surface2 metal A 6 cross-section3 metal B 7 under surface4 coatingFigure 1 A ty