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、 LAWBS 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 T
3、his 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 obtain
4、ed 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” fac
5、ility 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 oblig
6、ations. 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 d
7、ocument 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. Date CommentsEUROPEAN 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 dplacemen
9、t 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 Europea
10、n 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, Fre
11、nch, 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, Denm
12、ark, 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-1050
13、 Brussels 2001 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 12239:2001 EEN 12239:2001 (E) 2 Contents Page Foreword. 3 1 Scope . 4 2 Normative references . 4 3 Terms, definitions and symbols 4 3.1 Terms and definitions 4 3.2 Symb
14、ols 6 4 Types of air terminal devices. 8 5 Method of test 8 5.1 Principle 8 5.2 Test set-up 9 5.3 Installation . 10 5.3.1 General . 10 5.3.2 Test installation D 10 5.3.3 Test installation P 10 5.4 Velocity instruments 10 5.5 Test room 11 5.6 Procedure 11 5.6.1 General . 11 5.6.2 Measuring with trace
15、r gas. 12 5.6.3 Measuring with the zero pressure-difference method.13 5.7 Expression of results. 15 5.7.1 Pressure measurement for a given flow rate 15 5.7.2 Velocity measurement 15 5.7.3 Induction rate measurement . 18 6 Uncertainty 18EN 12239:2001 (E) 3 Foreword This European Standard has been pre
16、pared 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 February 2002, and conflicting national
17、 standards shall be withdrawn 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,
18、 Iceland, Ireland, Italy, Luxembourg, 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 app
19、lications, including the specification 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 1223
20、8. 2 Normative references 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
21、revisions of any of these 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
22、testing and rating for mixed 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 t
23、ubes inserted in circular 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 an
24、d definitions For the purposes 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 prima
25、ry airflow rate q p volume of air entering the air terminal device in unit time from an upstream duct 3.1.3 internally induced airflow rate q i volume of air in unit time induced into the primary airflow inside the air terminal device 3.1.4 total airflow rate q t volume of air in unit time, discharg
26、ed into the room from the air terminal deviceEN 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 te
27、rminal 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 the primary air tem
28、perature 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 a v maximum horizontal distance from the air terminal device (or wall) to the rectangle circumscribing the specified isovel, independent of the di
29、stance from the floor as shown in Figure 4 3.1.12 width of the specified isovel b v maximum width of the rectangle circumscribing the specified isovel perpendicular to a v , independent of the distance from the floor as shown in Figure 4 3.1.13 height of the specified isovel h v maximum height above
30、 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 = q i/ q p 3.1.15 static pressure p s static pressure relative to the atmosphere 3.1.16 dynamic pressure p d dynamic pressure corresponding to the m
31、ean velocity in the connecting duct. For plenum connection without duct, the dynamic pressure is equal to zero 3.1.17 total pressure p t sum of the static and dynamic pressures 3.1.18 equivalent diameter D e equivalent diameter of the nominal size of the ductEN 12239:2001 (E) 6 3.2 Symbols The nomen
32、clature shown in Table 1 is used throughout this European Standard. Table 1 Symbols used in the testing of air terminal devices Symbol Quantity SI unit A Area m 2 A d Area corresponding to the cross section of the nominal size of the duct to which the device is fitted (neck area) m 2 a v Length of i
33、sovel m b R Width of test room or installation m b v Width of isovel m C i Concentration measured in the internally induced airflow C p Concentration measured in the primary airflow C t Concentration measured in the total airflow of the air terminal device D e Equivalent diameter Ad 2 m D h Hydrauli
34、c diameter perimeter 4 Ad m d Diameter m h v Height of isovel m h R Height of test room or installation m i Induction rate l R Length of test room or installation m p sa Absolute static pressure Pa p a Atmospheric pressure Pa p s Static pressure or static gauge pressure (p sa- p a ) Pa p ta Stagnati
35、on (or absolute total) pressure PaEN 12239:2001 (E) 7 Table 1 Symbols used in the testing of air terminal devices (concluded) Symbol Quantity SI unit p t Total pressure (p ta- p a ) Pa p t1,2 Total pressure corresponding to a density of 1,2 kg m -3 Pa p tD Total pressure requirement of the device Pa
36、 p s1,2 Static gauge pressure corresponding to an air density of 1,2 kg m -3 Pa p d Dynamic pressure (Velocity pressure) 2 2 Pa p Pressure difference (for a pressure difference device) Pa q i Internally induced airflow rate m 3 s -1 q p Primary airflow rate m 3 s -1 q t Total airflow rate m 3 s -1 v
37、 Velocity m s -1 v m Mean air velocity m s -1 v x Maximum velocity at distance x from centre of supply air terminal device m s -1 p Primary air temperature K i Induced air temperature K t Total air temperature K r Reference air temperature of the room K p Primary air temperature difference K Density
38、 of air kg m -3EN 12239:2001 (E) 8 4 Types 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 a
39、nd ): ceiling mounted devices. NOTE 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: th
40、e air terminal device is connected 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 he
41、ights from the air terminal 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 fo
42、r v = 0,20 m s -1shall be determined. For air terminal devices mainly designed for industrial purposes, the isovel for v = 0,30 m s -1shall 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 D e _ p S q
43、p q i q t 1,5 D e _ Figure 1 Test set-up for Type 1 devices p S Test installation P Test installation D Figure 2 Test set-up for Type 2 devicesEN 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 prima
44、ry air temperature shall be measured at a position 3D eupstream 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 s
45、hall be equal to the nominal size of the device. The connecting duct shall be straight and at least 20D elong to ensure uniform velocity profile or shall include an efficient flow straightener located at a position at least 3D efrom any part of the air terminal device. The straightener cells should
46、have an axial length at least equal to six times the hydraulic diameter of their cross-section. The plane of static pressure measurement shall be at 1,5D eupstream of the air terminal device. A static pressure traverse shall be taken on two orthogonal diameters in order to obtain the maximum and min
47、imum values. The measured pressures 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 -1at a distance
48、 of 2D efrom the centre of the 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 2D efrom the centre of the air terminal device inlet. 5.4
49、Velocity instruments The measurement 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
copyright@ 2008-2019 麦多课文库（www.mydoc123.com）网站版权所有
备案/许可证编号：苏ICP备17064731号-1