BS EN 16211-2015 Ventilation for buildings Measurement of air flows on site Methods《建筑物通风 现场气流的测量 方法》.pdf

1、BSI Standards PublicationBS EN 16211:2015Ventilation for buildings Measurement of air flows onsite MethodsBS EN 16211:2015 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN 16211:2015. The UK participation in its preparation was entrusted to TechnicalCommittee RHE

2、/2, Ventilation for buildings, heating and hot water services.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.

3、The British Standards Institution 2015.Published by BSI Standards Limited 2015ISBN 978 0 580 84174 3 ICS 17.120.10; 91.140.30 Compliance with a British Standard cannot confer immunity from legal obligations.This British Standard was published under the authority of the Standards Policy and Strategy

4、Committee on 31 July 2015.Amendments/corrigenda issued since publicationDate T e x t a f f e c t e dEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 16211 July 2015 ICS 17.120.10; 91.140.30 English Version Ventilation for buildings - Measurement of air flows on site - Methods Systmes de ventilat

5、ion pour les btiments - Mesurages de dbit dair dans les systmes de ventilation - Mthodes Lftung von Gebuden - Luftvolumenstrommessung in Lftungssystemen - Verfahren This European Standard was approved by CEN on 5 March 2015. CEN members are bound to comply with the CEN/CENELEC Internal Regulations w

6、hich 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

7、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 member

8、s 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, Portugal

9、, 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

10、and by any means reserved worldwide for CEN national Members. Ref. No. EN 16211:2015 EBS EN 16211:2015Contents Page Foreword . 4 1 Scope 5 2 Normative references . 5 3 Terms, definitions and symbols 5 3.1 Terms and definitions . 5 3.2 Symbols . 5 4 Principles and parameters of influence 7 4.1 Hydrau

11、lic diameter 7 4.2 Flow disturbances . 7 4.3 Air density, 7 4.4 Dynamic pressure, pd7 4.5 Corrections for air density, . 8 5 Sources of errors 8 5.1 General . 8 5.2 Systematic errors 9 5.3 Random errors . 10 6 Measurement uncertainty . 10 6.1 Overall measurement uncertainty . 10 6.2 Standard instrum

12、ent uncertainty, u1. 11 6.3 Standard method uncertainty, u2. 11 6.4 Standard reading uncertainty, u3. 11 6.5 Expanded measurement uncertainty, Um. 11 7 Measurement requirements . 12 7.1 Method requirements and corrections . 12 7.2 Measurements using a manometer . 12 7.3 Measurements using an anemome

13、ter . 13 7.4 Measurements using Pitot static tube 13 7.5 Measuring temperature and barometric pressure . 13 7.6 Mean value calculation of measurement signal . 13 8 Methods for measurement of air flows in ducts ID (In Duct) methods . 13 8.1 Overview of recommended methods 13 8.2 Point velocity measur

14、ements using a Pitot static tube (method ID 1) or an anemometer (method ID 2) . 14 8.2.1 Method description . 14 8.2.2 Preparations to be made at the site of measurement . 15 8.2.3 Measurement procedure 18 8.2.4 Corrections of measured values and calculation of air flow 19 8.2.5 Standard method unce

15、rtainty 20 8.3 Fixed devices for flow measurement Method ID 3 20 8.3.1 Method description . 20 8.3.2 Preparations of measurements Equipment . 20 8.3.3 Measurement procedure 21 8.3.4 Correction of measured values . 21 8.3.5 Standard method uncertainty 21 8.4 Tracer gas measurement Method ID 4 . 21 8.

16、4.1 Method description . 21 8.4.2 Equipment 22 8.4.3 Calculation of air flow . 23 8.4.4 Standard measurement uncertainty 23 8.4.5 Conditions for homogeneous mixing of tracer gas . 24 EN 16211:2015 (E)BS EN 16211:20159 Methods for measurement of air flows in Supply ATDs (air terminal devices) ST (Sup

17、ply (Air) Terminal (Devices) methods 25 9.1 Overview of recommended methods 25 9.2 Measurement of reference pressure Method ST 1 . 25 9.2.1 Introduction . 25 9.2.2 Equipment 26 9.2.3 Correction of measured values . 26 9.2.4 Standard method uncertainty 27 9.3 Measurement with tight bag Method ST 2 .

18、27 9.3.1 Method description . 27 9.3.2 Limitations . 27 9.3.3 Equipment 27 9.3.4 Preparation 28 9.3.5 Measurement . 28 9.3.6 Correction of measured values . 28 9.3.7 Standard method uncertainty 28 9.4 Measurements with flow hood Method ST 3 . 28 9.4.1 Introduction . 28 9.4.2 Equipment 29 9.4.3 Measu

19、rement . 30 9.4.4 Correction of measured values . 31 9.4.5 Standard method uncertainty 31 10 Methods for Exhaust ATDs (air terminal devices) ET (Exhaust (Air) Terminal (Devices) methods . 32 10.1 Overview of recommended methods 32 10.2 Measurement of reference pressure at exhaust ATD Method ET 1 32

20、10.2.1 Method description . 32 10.2.2 Limitations . 33 10.2.3 Equipment 33 10.2.4 Correction of measured values . 33 10.2.5 Standard method uncertainty 34 10.3 Measurement using a flow hood Method ET 2 34 10.3.1 Introduction . 34 10.3.2 Equipment 34 10.3.3 Measurement . 35 10.3.4 Correction of measu

21、red values . 36 10.3.5 Standard method uncertainty 36 Annex A (informative) Uncertainties . 37 A.1 Examples of calculations . 37 A.2 Compound uncertainties 38 A.3 Example of applications . 38 Bibliography . 39 EN 16211:2015 (E)BS EN 16211:2015Foreword This document (EN 16211:2015) has been prepared

22、by Technical Committee CEN/TC 156 “Ventilation for buildings”, the secretariat of which is held by BSI. 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 January 2016, and conflicting national stand

23、ards shall be withdrawn at the latest by January 2016. 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. Measurement methods which are b

24、oth correct and easy to use are developed and standardized to enable the commissioning and operational monitoring of air processing installations. Interior climate and air quality can often be improved considerably if the heating and ventilation system is managed in a way that ensures good functioni

25、ng in the long term. It is thus important that the system is designed and constructed to allow measurement and monitoring to be performed using established and approved methods. According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following countries are bou

26、nd 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, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portuga

27、l, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. EN 16211:2015 (E)BS EN 16211:20151 Scope This European Standard specifies simplified methods for the measurement of air flows on site. It provides a description of the air flow methods and how measurements are

28、 performed within the margins of stipulated method uncertainties. One measurement method is to take point velocity measurements across a cross-section of a duct to obtain the air flow. This simplified method is an alternative to the method described in ISO 3966 and EN 12599. This European Standard r

29、equests certain measurement conditions (length of straight duct and uniform velocity profile) to be met to achieve the stipulated measurement uncertainties for the simplified method. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and

30、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. EN 12792, Ventilation for buildings Symbols, terminology and graphical symbols EN 14277, Ventilation

31、for buildings Air terminal devices Method for airflow measurement by calibrated sensors in or close to ATD/plenum boxes 3 Terms, definitions and symbols 3.1 Terms and definitions For the purposes of this document, the terms and definitions given in EN 12792 apply. 3.2 Symbols The following symbols a

32、re used. EN 16211:2015 (E)BS EN 16211:2015Symbol Description SI Unit Symbol Description SI Unit t Time s O Perimeter m Density kg/m3p Pressure Pa sStandard conditions air density = 1,2 kg/m3pdDynamic pressure Pa rReal density kg/m3ps Static pressure Pa tracerTracer gas density kg/m3pt Total pressure

33、 Pa ductDuct air density kg/m3pu Measured pressure Pa A Cross-section Area m2p Differential pressure Pa a, b, c, etc. Dimensions of length mm pu Measured differential pressure Pa L Mixing length mm q Air flow m3/s, l/s H Height of duct mm qkCorrected air flow m3/s, l/s W Width of duct mm qs Tracer g

34、as flow m3/s, l/s B Barometric pressure hPa qsductTracer gas flow at duct temperature m3/s, l/s C Contaminant concentration ppm qstracerTracer gas flow at rotameter temperature m3/s, l/s CiInitial tracer gas concentration ppm qt Total air flow m3/s, l/s CsTracer gas concentration in stationary condi

35、tion ppm qu Measured air flow m3/s, l/s D Diameter mm Temperature C DhHydraulic diameter mm duct Temperature in duct C kccoverage factor - tracerTemperature of tracer gas C k1Correction factor for density - V Volume m3k2Correction factor for duct shape - v Air velocity m/s k Flow factor - vsStandard

36、 air velocity m/s L1Smaller dimension of a rectangular duct mm vrReal air velocity m/s L2Larger dimension of a rectangular duct mm vmAir velocity, mean value m/s u1Standard Instrument uncertainty - u2Standard Method uncertainty - u3Standard Reading uncertainty - umStandard measurement uncertainty -

37、UmExpanded measurement uncertainty - EN 16211:2015 (E)BS EN 16211:20154 Principles and parameters of influence 4.1 Hydraulic diameter The hydraulic diameter is the diameter of a circular duct which causes the same pressure drop at equal air velocity and equal friction coefficient, and is defined by

38、the following formula: Dh= 4 A/O (1) For a rectangular duct this becomes: Dh= 2 L1 L2/ (L1+ L2) (2) where L1and L2are the sides of the duct. For a circular duct this becomes: Dh= D (3) 4.2 Flow disturbances Flow disturbances in ducts result in irregular velocity profiles. NOTE Flow seldom has a symm

39、etrical appearance except after long straight sections. The symmetry is often disturbed by varying resistance, for example after a bend, an area decrease or an area increase. The velocity profile also becomes disturbed by a damper and T-piece as well as before and after a fan. 4.3 Air density, The d

40、ensity of dry air varies with air pressure and temperature in accordance with the following approximating formula: 273 151 2931013 25 273 15,B=+(4) NOTE The relative humidity of the air (RH) has very little influence on the density of air at room temperature. The density of air at 20 C and 1 013,25

41、hPa which is saturated with water vapour is only approximately 1 % less than equivalent dry air. In a low-pressure system it is hardly necessary to consider the influence of static pressure on air density. In a high-pressure system, however, it can be necessary. The calculation is then performed as

42、follows: 0 01 273 151 2931013 25 273 15, ,sBp+=+(5) 4.4 Dynamic pressure, pdWhen measuring with a Pitot static tube a dynamic pressure is measured. The dynamic pressure can be used to calculate the air velocity by the use of the following formula: 22dvp= (6) EN 16211:2015 (E)BS EN 16211:20154.5 Corr

43、ections for air density, When presenting a measured air flow or velocity, it should be stated if it is the real air flow or the flow converted to standard conditions that is presented. The measurements should correspond to the designed air flow values of the system (real or standard air flow). The m

44、ethods in this standard present the measurements as real air flow. How to convert between standard and real velocity is described in 4.5. The same conversion is also valid for air flow. The real flow rate of air is as it is at the present temperature and barometric pressure of the air. Standard air

45、flow is used to present the air flow at standard condition of 1 013,25 hPa and 20 C. A fan transports approximately the same amount of air independent of air density. The amount of standard flow changes with air density. The instrument in use can measure real or standard air flow or it could require

46、 calibration conditions to display correctly. Compensate accordingly, especially when used for other conditions than calibration condition or standard conditions of 1 013,25 hPa and 20 C. The barometric pressure will decrease with altitude and also vary with weather. Convert real flow or velocity to

47、 standard flow or velocity by using the following formula: vs= vr r/ s(7) 5 Sources of errors 5.1 General There are many factors which affect the measurement results which shall be checked in connection with measuring. These factors are for example: a) calibration equipment, which shall be regularly

48、 compared with a traceable norm (calibration unit); b) calibrated measurement instruments; c) calibration intervals; d) examination of instruments long term stability; e) instruments temperature or density compensation; f) random instrument uncertainties; g) random reading uncertainties; h) variatio

49、ns in the measured quantity; i) measurement methods adapted to different installation cases; j) random uncertainties in measurement methods; k) measurement methods influence on the flow rate; l) variations in the exterior climate; m) air flow stability. EN 16211:2015 (E)BS EN 16211:2015Certain sources of error are difficult to manipulate, others can be reduced or even eliminated. Errors in given data input can be the result of measurements which have been affected by sys