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1、BRITISH STANDARD BS EN 12239:2001 Ventilation for buildings Air terminal devices Aerodynamic testing and rating for displacement flow applications The European Standard EN 12239:2001 has the status of a British Standard ICS 91.140.30 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT
2、 LAW BS EN 12239:2001 This British Standard, having been prepared under the direction of the Engineering Sector Policy and Strategy Committee, was published under the authority of the Standards Policy and Strategy Committee on 16 October 2001 BSI 16 October 2001 ISBN 0 580 38233 8 National foreword
3、This British Standard is the official English language version of EN 12239:2001. The UK participation in its preparation was entrusted to Technical Committee RHE/2, Air distribution and air diffusion, which has the responsibility to: A list of organizations represented on this committee can be obtai
4、ned on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” fa
5、cility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obli
6、gations. aid enquirers to understand the text; present to the responsible European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This
7、document comprises a front cover, an inside front cover, the EN title page, pages 2 to 18, an inside back cover and a back cover. The BSI copyright date displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. DateComments EUROPEAN STANDARD
8、 NORME EUROPENNE EUROPISCHE NORM EN 12239 August 2001 ICS 91.140.30 English version Ventilation for buildings Air terminal devices Aerodynamic testing and rating for displacement flow applications Ventilation des btiments Bouches dair Essais arodynamiques et caractrisation pour applications dplaceme
9、nt dair Lftung von Gebuden Luftdurchlsse Aerodynamische Prfung und Bewertung fr Anwendung bei Verdrngungsstrmung This European Standard was approved by CEN on 22 June 2001. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this Europe
10、an 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 Management Centre or to any CEN member. This European Standard exists in three official versions (English, Fr
11、ench, 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 Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Den
12、mark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: rue de Stassart, 36 B-105
13、0 Brussels 2001 CENAll rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 12239:2001 E EN 12239:2001 (E) 2 ContentsPage Foreword. 3 1Scope . 4 2Normative references .4 3Terms, definitions and symbols4 3.1Terms and definitions 4 3.2Symbols 6 4
14、Types of air terminal devices.8 5Method of test 8 5.1Principle 8 5.2Test set-up 9 5.3Installation. 10 5.3.1General . 10 5.3.2Test installation D 10 5.3.3Test installation P 10 5.4Velocity instruments 10 5.5Test room 11 5.6Procedure 11 5.6.1General . 11 5.6.2Measuring with tracer gas. 12 5.6.3Measuri
15、ng with the zero pressure-difference method. 13 5.7Expression of results. 15 5.7.1Pressure measurement for a given flow rate 15 5.7.2Velocity measurement 15 5.7.3Induction rate measurement. 18 6Uncertainty 18 EN 12239:2001 (E) 3 Foreword This European Standard has been prepared by Technical Committe
16、e 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 February 2002, and conflicting national standards shall be withdra
17、wn at the latest by February 2002. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, L
18、uxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom. EN 12239:2001 (E) 4 1 Scope This European Standard specifies methods for the laboratory aerodynamic testing and rating of low velocity air terminal devices for displacement flow applications, including the s
19、pecification of suitable test facilities and measurement techniques. The standard gives only tests for the assessment of characteristics of the air terminal devices under non-isothermal conditions. This standard applies to Class IV air terminal devices as defined in EN 12238. 2 Normative references
20、This European Standard incorporates by dated or undated reference, provisions from other publications. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated references the subsequent amendments to or revisions of any of these
21、publications apply to this European Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies (including amendments). EN 12238, Ventilation for buildings Air terminal devices Aerodynamic testing and rating for mix
22、ed flow applications. prEN 13182:1998, Ventilation for buildings Instrumentation requirements for air velocity measurements in ventilated spaces. EN ISO 5167-1, Measurement of fluid flow by means of pressure differential devices Part 1: Orifice plates, nozzles and Venturi tubes inserted in circular
23、cross-section conduits running full (ISO 5167-1:1991). CR 12792, Ventilation for buildings Symbols and terminology. ISO 5221, Air distribution and air diffusion Rules to methods of measuring airflow rate in an air handling duct. 3 Terms, definitions and symbols 3.1 Terms and definitions For the purp
24、oses of this European Standard, the terms and definitions given in CR 12792, together with the following, apply. 3.1.1 low velocity air terminal device air terminal device which is designed for thermally controlled ventilation e.g. displacement flow applications 3.1.2 primary airflow rate qp volume
25、of air entering the air terminal device in unit time from an upstream duct 3.1.3 internally induced airflow rate qi volume of air in unit time induced into the primary airflow inside the air terminal device 3.1.4 total airflow rate qt volume of air in unit time, discharged into the room from the air
26、 terminal device EN 12239:2001 (E) 5 3.1.5 primary air temperature ? ? ? ? p air temperature of the primary airflow 3.1.6 induced air temperature ? ? ? ? i air temperature of the internally induced airflow 3.1.7 total air temperature ? ? ? ? t air temperature of the total airflow from the air termin
27、al device 3.1.8 reference air temperature of the room ? ? ? ? r average of at least five measurements of the air temperature at a height of 1,1 m from the floor and outside the area directly influenced from the device 3.1.9 primary air temperature difference ? ? ? ? ? ? ? p algebraic difference of t
28、he primary air temperature and the reference air temperature of the occupied zone 3.1.10 isovel loci of points of equal mean velocity 3.1.11 length of the specified isovel av maximum horizontal distance from the air terminal device (or wall) to the rectangle circumscribing the specified isovel, inde
29、pendent of the distance from the floor as shown in Figure 4 3.1.12 width of the specified isovel bv maximum width of the rectangle circumscribing the specified isovel perpendicular to av, independent of the distance from the floor as shown in Figure 4 3.1.13 height of the specified isovel hv maximum
30、 height above floor of the specified isovel as shown in Figure 5 3.1.14 induction rate i the ratio of the internally induced airflow rate and primary airflow rate i = qi / qp 3.1.15 static pressure ps static pressure relative to the atmosphere 3.1.16 dynamic pressure pd dynamic pressure correspondin
31、g to the mean velocity in the connecting duct. For plenum connection without duct, the dynamic pressure is equal to zero 3.1.17 total pressure pt sum of the static and dynamic pressures 3.1.18 equivalent diameter De equivalent diameter of the nominal size of the duct EN 12239:2001 (E) 6 3.2 Symbols
32、The nomenclature shown in Table 1 is used throughout this European Standard. Table 1 Symbols used in the testing of air terminal devices SymbolQuantitySI unit AAream2 AdArea corresponding to the cross section of the nominal size of the duct to which the device is fitted (neck area) m2 avLength of is
33、ovelm bRWidth of test room or installationm bvWidth of isovelm CiConcentration measured in the internally induced airflow CpConcentration measured in the primary airflow CtConcentration measured in the total airflow of the air terminal device De Equivalent diameter ? ? ? ? ? ? ? ? ? A d 2 m Dh Hydra
34、ulic diameter ? ? ? ? ? ? ? ? perimeter 4Ad m dDiameterm hvHeight of isovelm hRHeight of test room or installationm iInduction rate lRLength of test room or installationm psaAbsolute static pressurePa paAtmospheric pressurePa psStatic pressure or static gauge pressure (psa - pa)Pa ptaStagnation (or
35、absolute total) pressurePa EN 12239:2001 (E) 7 Table 1 Symbols used in the testing of air terminal devices (concluded) SymbolQuantitySI unit ptTotal pressure (pta - pa)Pa pt1,2Total pressure corresponding to a density of 1,2 kg?m-3 Pa ptDTotal pressure requirement of the devicePa ps1,2Static gauge p
36、ressure corresponding to an air density of 1,2 kg?m-3Pa pd Dynamic pressure (Velocity pressure) ? ? ? ? ? ? ? ? 2 2 Pa ?pPressure difference (for a pressure difference device)Pa qiInternally induced airflow ratem3?s-1 qpPrimary airflow ratem3?s-1 qtTotal airflow ratem3?s-1 vVelocitym?s-1 vmMean air
37、velocitym?s-1 vxMaximum velocity at distance x from centre of supply air terminal devicem?s-1 ?pPrimary air temperatureK ?iInduced air temperatureK ?tTotal air temperatureK ?rReference air temperature of the roomK ?pPrimary air temperature differenceK ?Density of airkg?m-3 EN 12239:2001 (E) 8 4 Type
38、s of air terminal devices The air terminal devices can be divided into the following types: Type 1 (categories ? and ?): devices for horizontal discharge of air; Type 2 (categories ? and ?): floor mounted devices with vertical discharge of air; Type 3 (categories ? and ?): ceiling mounted devices. N
39、OTE Category ? is applicable to devices without internal induction. Category ? is applicable to devices with internal induction. Two different test installations can be identified: test installation D: the air terminal device is connected to a duct; test installation P: the air terminal device is co
40、nnected to the plenum without duct. 5 Method of test 5.1 Principle The test consists of the determination of the pressure loss, isovel and, for category ? devices, the induction rate of the air terminal device. The air velocity shall be measured at different distances and heights from the air termin
41、al device under non-isothermal conditions. The air velocity shall be measured at sufficient points and locations to determine the specified isovel, according to the uncertainty given in clause 6. For air terminal devices mainly designed for comfort ventilation, the isovel for v = 0,20 m?s-1 shall be
42、 determined. For air terminal devices mainly designed for industrial purposes, the isovel for v = 0,30 m?s-1 shall be determined. EN 12239:2001 (E) 9 5.2 Test set-up The test set-up is shown in Figures 1 and 2. Flow straightener Type 1? Type 1? Heating elements 1,5 De _ ?pS qp qi qt 1,5 De _ Figure
43、1 Test set-up for Type 1 devices ?pSTest installation PTest installation D Figure 2 Test set-up for Type 2 devices EN 12239:2001 (E) 10 5.3 Installation 5.3.1 General The air terminal device shall be installed in accordance with the manufacturers recommendation. The primary air temperature shall be
44、measured at a position 3De upstream of the air terminal device. The temperature shall not vary by more than 0,5 K, and the airflow rate shall not vary by more than 2 % during the test. 5.3.2 Test installation D The connection between the duct and the air terminal device shall be equal to the nominal
45、 size of the device. The connecting duct shall be straight and at least 20De long to ensure uniform velocity profile or shall include an efficient flow straightener located at a position at least 3De from any part of the air terminal device. The straightener cells should have an axial length at leas
46、t equal to six times the hydraulic diameter of their cross-section. The plane of static pressure measurement shall be at 1,5De upstream of the air terminal device. A static pressure traverse shall be taken on two orthogonal diameters in order to obtain the maximum and minimum values. The measured pr
47、essures shall not differ by more than 10 % from the pressure at the selected point of test in the plane of measurement. As an alternative method, a piezometer ring may be used. 5.3.3 Test installation P The air velocity in the plenum shall not exceed 1 m?s-1 at a distance of 2De from the centre of t
48、he air terminal device inlet. The static pressure shall be measured in the plenum where the air velocity is less than 1 m?s-1. The primary air temperature shall be measured in the plenum at a maximum distance of 2De from the centre of the air terminal device inlet. 5.4 Velocity instruments The measu
49、rement of low velocities shall be made with instruments in accordance to prEN 13182:1998. EN 12239:2001 (E) 11 5.5 Test room The test shall be conducted in an enclosed room having all surfaces orthogonal at the corners and any surfaces over which the supply airflows shall be smooth and flat. Typical dimensions of the test room are 7,5 m in length, 5,6 m in width and 2,8 m in height. Larger or smaller test rooms shall have a width to height ratio between 1,5 and 2,2. The minimum dimensions of
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