1、BRITISH STANDARD BS 6583:1985 Methods for Volumetric testing for rating of fan sections in central station air handling units (including guidance on rating) UDC 628.83:628.922:621.63.001.4BS6583:1985 This British Standard, having been prepared under the directionof the Refrigeration, Heating and Air
2、 Conditioning Standards Committee, was published under the authority ofthe Board of BSI and comes intoeffect on 28February1985 BSI 07-1999 The following BSI references relate to the work on this standad: Committee reference RHE/6 Draft for comment 82/75373 DC ISBN 0 580 14345 7 Committees responsibl
3、e for this British Standard The preparation of this British Standard was entrusted by the Refrigeration, Heating and Air Conditioning Standards Committee (RHE/-) to Technical Committee RHE/6, upon which the following bodies were represented: Boiler and Radiator Manufacturers Association Limited Brit
4、ish Refrigeration Association Building Services Research and Information Association Chartered Institution of Building Services Department of Health and Social Security Department of the Environment (Building Research Establishment) Department of the Environment (Property Services Agency) Heating an
5、d Air Conditioning Manufacturers Association Heating and Ventilating Contractors Association Institute of Domestic Heating Engineers Institute of Refrigeration Manufacturers Association of Radiators and Convectors Ltd. Ministry of Defence Coopted member Amendments issued since publication Amd. No. D
6、ate of issue CommentsBS6583:1985 BSI 07-1999 i Contents Page Committees responsible Inside front cover Foreword ii Section 1. General 1 0 Introduction 1 1 Scope 1 2 Definitions 1 Section 2. Volumetric testing for rating of fan sections 3 3 Test unit and test installation 3 4 Methods of test 4 5 Pres
7、entation of data 4 Section 3. Extrapolation of fan section data 6 6 Extrapolation of data for fan sections that are geometrically similar 6 7 Extrapolation of data for fan sections that are geometrically similar except for the fans 6 Appendix A Guide to the rating of air handling units 9 Figure 1 Mu
8、ltiple outlet units 3 Figure 2 Horizontal blow through cooling heating unit 4 Figure 3 Derivation of test unit fan section performance 5 Figure 4 Performance characteristics: fan rated and fan section tested 7 Figure 5 Performance characteristics: fan rated and fan section calculated 8 Publications
9、referred to Inside back coverBS6583:1985 ii BSI 07-1999 Foreword This British Standard has been prepared under the direction of the Refrigeration, Heating and Air Conditioning Standards Committee in response to requests from industry. The initial draft was prepared by the Heating, Ventilating and Ai
10、r Conditioning Manufacturers Association and has taken account of the work of the Air Conditioning and Refrigeration Institute of America. It has been assumed in the drafting of this British Standard that the execution of its provisions is entrusted to appropriately qualified and experienced people.
11、 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 obligations. Summary of pages This document comprises
12、 a front cover, an inside front cover, pages i and ii, pages1 to 10, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.BS6583:1985 BSI 07-1999 1
13、Section 1. General 0 Introduction The basic component of an air handling unit is the fan section, comprising a fan or fans installed inside a cabinet. It is the characteristics of the fan section, and not the fan alone, that are used as the basis of assessment when rating the volumetric performance
14、of the unit. The great majority of air handling units incorporate a heat exchanger, either immediately upstream or downstream of the fan section. Depending on the proximity of the coil, its location can modify the fan performance. The test unit consequently has to comprise at least a coil section, w
15、ith coil, in addition to the fan section. The measured pressure/volume characteristics of the test unit are corrected to arrive at the rated performance of the fan section alone. This rated performance therefore takes into account not only the entry losses associated with mounting a fan in a cabinet
16、, but also the effect introduced by a coil mounted in close proximity. Separate series of tests are necessary for upstream and downstream coil locations, to derive fan section performance ratings for draw through and blow through units respectively. This is important because blow through units, by v
17、irtue of their fans discharging into a plenum, incur expansion losses which can be significant. 1 Scope This British Standard describes methods for volumetric testing for rating of fan sections in central station air handling units. It specifies how fan section test data may be extrapolated to cover
18、: a) fan sections that are geometrically similar in all respects to the one tested; b) fan sections where the components and air passages, but not the fans, are geometrically similar. Appendix A provides a guide to the volumetric and thermal rating of complete air handling units. NOTEThe titles of t
19、he publications referred to in this standard are listed on the inside back cover. 2 Definitions For the purposes of this British Standard the following definitions apply: 2.1 central station air handling unit a factory-made encased assembly that consists of a fan or fans and other necessary equipmen
20、t to perform one or more of the functions of circulating, cleaning, heating, cooling, humidifying, dehumidifying, and mixing of air, but that does not include a direct source of heating or cooling. The unit is capable of use with duct work having a static resistance of more than100Pa 2.2 fan a rotar
21、y machine that maintains a continuous flow of air at a pressure ratio not normally exceeding1.3 2.3 impeller the rotating part of a fan that, by means of its blades, transfers energy to the air 2.4 fan casing those stationary parts of a fan that direct the flow of air from the fan inlet opening(s) t
22、o the fan outlet opening 2.5 fan section a cabinet, part of an air handling unit, in which a fan, or fans, is installed 2.6 coil section that part of an air handling unit in which the cooling or heating coil is installed 2.7 draw through central station air handling unit a unit with the coil section
23、 upstream of the supply fan 2.8 blow through central station air handling unit a unit with the coil section downstream of the supply fan 2.9 heating capacity the sensible heat output of the heat exchangers within the air handling unitBS6583:1985 2 BSI 07-1999 2.10 cooling capacity the total heat rem
24、oval capacity of the heat exchangers within the unit. It is the sum of the sensible and latent heat capacities of the heat exchangers 2.11 air handling capacity the quantity of standard air leaving the air handling unit against a specified pressure; this pressure is the static pressure external to t
25、he complete unit against which the air is to be delivered NOTEAll air volumes, static and dynamic pressures are related to a straight outlet duct of the unit outlet size of a length as defined in BS848-1. 2.12 standard air atmospheric air having a density of1.2kg/m 3exactly 2.13 pressure ratio for a
26、 fan with a free outlet the ratio of the absolute pressure at the fan outlet to the absolute pressure at the fan inlet. For a fan with a ducted outlet the ratio of the absolute total pressure at the fan outlet to the absolute total pressure at the fan inletBS6583:1985 BSI 07-1999 3 Section 2. Volume
27、tric testing for rating of fan sections 3 Test unit and test installation 3.1 Specification of test unit The following requirements shall be complied with. a) The test unit shall consist of a fan section and a coil section only. b) Blow through test units shall include the down-stream coil(s). c) Th
28、e coil with the largest face area catalogued shall be used. d) The coil shall be mounted in its most restrictive catalogued location relative to the fan. e) The coil shall have an air resistance of at least20Pa at a2.5m/s face velocity of standard air. f) Internally mounted fan motors shall be mount
29、ed in their most restrictive intended location relative to the fan. 3.2 Test installation 3.2.1 General. Test units shall be tested using any one of the following installations from BS848-1:1980: a) Figure 26, but taking account of 27.5.3 and 27.5.5 of that standard; b) Figure 27; c) Figure 29. 3.2.
30、2 Single outlet draw through units. An outlet duct shall be provided that is equal to the fan section outlet size catalogued by the manufacturer. 3.2.3 Multiple outlet draw through units. Each fan outlet shall be ducted as shown inFigure 1. The size of the outlet ducts shall be that published by the
31、 manufacturer for the outlets of the fan section. 3.2.4 Single outlet blow through units. An outlet duct shall be provided that is equal to the coil section outlet size catalogued by the manufacturer. 3.2.5 Blow through cooling and heating units (as inFigure 2). The heating coil position shall be bl
32、anked off and the unit tested with horizontal air discharge, with a duct equal to the cooling duct outlet. NOTEOne multiple outlet unit can have one or more outlets. For illustration three outlets are shown. Figure 1 Multiple outlet unitsBS6583:1985 4 BSI 07-1999 4 Methods of test 4.1 General Tests
33、shall be made at the impeller speed(s) necessary to cover the specified range of duties of the unit. The coil shall be de-energized during the tests. 4.2 Coil resistance test The air resistance of the dry coil shall be determined in accordance with BS5141-1 or BS5141-2. 4.3 Measurements The measurem
34、ent of rates of flow, pressures, temperatures, velocities and fan shaft power shall be made in accordance with BS848-1. 5 Presentation of data The data shall be presented as follows. a) Plot test unit static pressure (in Pa) against air volume flow rate (in m 3 /s standard air), for each speed for w
35、hich tests were conducted, to produce performance curves of the test unit (with coil). b) Plot coil resistance (in Pa) against air volume flow rate (in m 3 /s standard air) using the same scales for pressure and air volume flow rate as used in a). c) Add to each curve of a) the coil resistance taken
36、 from b), producing a corrected set of pressure against air volume flow rate curves (seeFigure 3). NOTEThis corrected set of curves is the rated performance of the fan section alone. d) Plot absorbed power at the fan shaft (in kW) against air volume flow rate for each speed for which tests were cond
37、ucted. NOTEThe power absorbed at a given speed and air volume flow rate is the same for both test unit (with coil) and fan section alone. Figure 2 Horizontal blow through cooling heating unitBS6583:1985 BSI 07-1999 5 Figure 3 Derivation of test unit fan section performanceBS6583:1985 6 BSI 07-1999 S
38、ection 3. Extrapolation of fan section data 6 Extrapolation of data for fan sections that are geometrically similar 6.1 General It is permitted for fan section performance curves for other geometrically similar units to be derived by the application of the Fan Laws to the data obtained in clause5 c)
39、 and d), in which case the criteria specified in6.2 shall apply. 6.2 Conditions for geometric similarity 6.2.1 General. The basis of fan section similarity shall always be the ratio of the diameters of the respective impellers. Linear dimensions shall be proportional to the diameter and areas shall
40、be proportional to the square of the diameter. NOTEThe requirements for similarity do not apply to the coils. 6.2.2 Fans. Fans shall be considered to be similar when they are within the limits defined by14.4 of BS848-1:1980. 6.2.3 Cabinets. Cabinets shall be considered to be similar when: a) the rat
41、io of all clearances between the cabinets and nearest fan casings, as measured parallel to the fan shaft, are $ D 2 /D 1 ; b) for multiple fan units the ratio of the clearances between adjacent fan casings, as measured parallel to the fan shaft, are $ D 2 /D 1 ; c) the ratio of the fan cabinet air f
42、low cross-sectional areas is $ 0.925(D 2 /D 1 ) 2 where D 1is the impeller tip diameter of the test unit; D 2is the impeller tip diameter of unit to be rated. 6.2.4 Other criteria. For similarity, the arrangement and location of motor and drive, internal bearings and bearing supports shall result in
43、 a ratio of the total free areas for air flow $ 0.925(D 2 /D 1 ) 2if the components are located at a distance # 0.5D 2from the inlet of the fan. 6.3 Conditions for the rating of fan sections 6.3.1 Single fan units. It is permitted for fan sections with a single fan to be rated from tests on a multip
44、le fan unit in which case the following requirements shall apply: a) the air volume flow rate and fan shaft power shall be directly proportional to the number of fans; b) the units shall be proportional in all relevant dimensions; c) there shall be no deviation from the relationship C M# 2C s(D 1 /D
45、 2 ) where 6.3.2 Multiple fan units. The rating of these units shall not be derived from tests on a single fan unit. 6.3.3 Draw through units. It is permitted that the rating of those draw through units that have a change of direction of air flow between the coil and the fan be derived from tests of
46、 units that do not include such a change, subject to the following: a) the plenum causing the change in direction shall be considered to be a component of the unit; b) the effect of the addition of the plenum as a component shall be taken into account (seeA.3). 6.3.4 Blow through units. There shall
47、be no distinction in rating between a vertical discharge and a horizontal discharge blow through unit. 7 Extrapolation of data for fan sections that are geometrically similar except for the fans 7.1 Single fan units The limits for impellers in6.2.2 shall not apply when fans of the same blade type th
48、at are not geometrically similar have been rated as fans alone by tests made in accordance with BS848-1. All other requirements of6.2 shall be met. The method of rating one fan section on the basis of tests on another shall be as follows: a) Using the fan manufacturers rating data, plot for each of
49、the speeds of4.1 the normalized performance curves of fan static pressure and absorbed power at the fan shaft against volume flow (seeFigure 4, curves A and B). These are obtained by multiplying a selected number of values of volume flow by100/Q Fand by multiplying the corresponding values of fan static pressure and absorbed power by100/P Nand100/W Frespectively, where C M is the clearance between fans of the multiple unit; C s is the clearance between the cabinet and the fan housing of a single fan unit. Q F is the free inlet and discharge volume flow
