1、 4100 N. FAIRFAX DR., SUITE 200 ARLINGTON, VIRGINIA 22203 2007 STANDARD for PERFORMANCE RATING OF REMOTE TYPE REFRIGERANT-COOLED LIQUID COOLERS Standard 480 Copyright Air-Conditioning and Refrigeration Institute Provided by IHS under license with ARI Not for ResaleNo reproduction or networking permi
2、tted without license from IHS-,-,-Price $10.00 (M) $20.00 (NM) Copyright 2007, by Air-Conditioning and Refrigeration Institute Printed in U.S.A. Registered United States Patent and Trademark Office IMPORTANT SAFETY DISCLAIMER ARI does not set safety standards and does not certify or guarantee the sa
3、fety of any products, components or systems designed, tested, rated, installed or operated in accordance with this standard/guideline. It is strongly recommended that products be designed, constructed, assembled, installed and operated in accordance with nationally recognized safety standards and co
4、de requirements appropriate for products covered by this standard/guideline. ARI uses its best efforts to develop standards/guidelines employing state-of-the-art and accepted industry practices. ARI does not certify or guarantee that any tests conducted under its standards/guidelines will be non-haz
5、ardous or free from risk. Note: This standard supersedes ARI Standard 480-2001. Copyright Air-Conditioning and Refrigeration Institute Provided by IHS under license with ARI Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-TABLE OF CONTENTS SECTION PAGE Section 1. P
6、urpose.1 Section 2. Scope1 Section 3. Definitions .1 Section 4. Test Requirements .3 Section 5. Rating Requirements3 Section 6. Minimum Data Requirements for Published Ratings 6 Section 7. Marking and Nameplate Data 6 Section 8. Conformance Conditions .6 TABLES Table 1. Standard Rating Conditions .3
7、 APPENDICES Appendix A. References Normative.7 Appendix B. References Informative.7 Copyright Air-Conditioning and Refrigeration Institute Provided by IHS under license with ARI Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-Copyright Air-Conditioning and Refriger
8、ation Institute Provided by IHS under license with ARI Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-ARI STANDARD 480-2007 1 PERFORMANCE RATING OF REMOTE TYPE REFRIGERANT-COOLED LIQUID COOLERS Section 1. Purpose 1.1 Purpose. The purpose of this standard is to est
9、ablish for Remote Type Refrigerant-Cooled Liquid Coolers: definitions; test requirements; rating requirements; minimum data requirements for Published Ratings; marking and nameplate data; and conformance conditions. 1.1.1 Intent. This standard is intended for the guidance of the industry, including
10、manufacturers, engineers, installers, contractors and users. 1.1.2 Review and Amendment. This standard is subject to review and amendment as technology advances. Section 2. Scope 2.1 Scope. This standard applies to Remote Type Refrigerant-Cooled Liquid Coolers of the Shell-and-Tube, Shell-and-U-Tube
11、, Shell-and-Coil, and Tube-in-Tube types using single component and azeotropic refrigerants only. 2.2 Exclusions. 2.2.1 This standard does not apply to liquid coolers supplied as part of factory-assembled liquid-chilling packages. 2.2.2 This standard does not apply to liquid coolers of the following
12、 types: a. Baudelot-type coolers b. Open-tank and coil coolers c. Open shell-and-tube coolers 2.2.3 This standard does not include sanitary provisions necessary for the handling of potable Liquids. 2.2.4 This standard does not apply to liquid coolers using zeotropic refrigerants. Section 3. Definiti
13、ons All terms in this document follow the standard industry definitions in the current edition of ASHRAE Terminology of Heating, Ventilation, Air Conditioning and Refrigeration, unless otherwise defined in this section. 3.1 Evaporating Temperature. The saturation temperature corresponding to the ref
14、rigerant pressure at the liquid cooler refrigerant outlet. 3.2 Field Fouling Allowance. Provision for the anticipated Fouling Factor during use. 3.2.1 Fouling Factor. The thermal resistance due to fouling accumulated on the heat transfer surface. 3.3 Liquid. Where used in this standard, the term Liq
15、uid by itself shall denote the fluid being cooled. 3.4 Mechanically-Cleanable Liquid Cooler. A liquid cooler in which Liquid flows through tubes which are accessible from both ends for cleaning by mechanical means, or accessible from one end when U-tubes are used. Copyright Air-Conditioning and Refr
16、igeration Institute Provided by IHS under license with ARI Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-ARI STANDARD 480-2007 2 3.5 Net Refrigerating Capacity. The useful heat exchange between the refrigerant and the Liquid being cooled. This value is the produc
17、t of the liquid mass flow rate and the difference in enthalpy between the Liquid entering and the Liquid leaving the cooler. 3.5.1 Clean Tube Capacity. The Net Refrigerating Capacity of the liquid cooler with clean tubes at Standard Rating Conditions expressed in Btu/h W. 3.6 Published Rating. A sta
18、tement of assigned values of those performance characteristics, under stated Rating Conditions, by which a unit may be chosen to fit its application. These values apply to all Remote Type Refrigerant-Cooled Liquid Coolers of like nominal size and type produced by the same manufacturer. As used herei
19、n, the term Published Rating includes all performance characteristics shown on the unit or published in specifications, advertising or other literature controlled by the manufacturer, at stated Rating Conditions. 3.6.1 Application Rating. A rating based on tests performed at application Rating Condi
20、tions. 3.6.2 Standard Rating. A rating based on tests performed at Standard Rating Conditions. 3.7 Rating Conditions. Any set of operating conditions under which a single level of performance results and which causes only that level of performance to occur. 3.7.1 Standard Rating Conditions. Rating C
21、onditions used as the basis of comparison for performance characteristics. 3.8 Remote Type Refrigerant-Cooled Liquid Cooler. A factory-made assembly in which heat is transferred from the Liquid to the refrigerant causing the refrigerant to evaporate and the Liquid to be cooled. The liquid cooler is
22、furnished separately for field installation in a refrigeration system, rather than for inclusion in a factory-assembled liquid-chilling package. 3.8.1 Direct-Expansion. A liquid cooler in which the refrigerant is normally fed into the tubes or coil by a flow-control device responsive to temperature
23、or pressure, or both, at some point in or near the cooler. 3.8.2 Flooded. A liquid cooler in which refrigerant level is maintained within the evaporating chamber and the Liquid being cooled is circulated through the tubes. 3.8.3 Shell-and-Coil. A liquid cooler in which heat is transferred through on
24、e or more coils contained within a closed shell. 3.8.4 Shell-and-Tube. A liquid cooler in which heat is transferred through a group of straight parallel tubes within a closed shell with the tubes terminating at both ends of the cooler. 3.8.5 Shell-and-U-Tube. A liquid cooler in which heat is transfe
25、rred through a U-tube bundle in a closed shell with the U-tubes terminating at one end of the cooler. 3.8.6 Spray-Type. A liquid cooler which is provided with a refrigerant distributor above a bundle of tubes not normally submerged in liquid refrigerant. The refrigerant which is not evaporated in it
26、s passage over the tubes is recirculated through the distributor. The liquid being cooled is circulated in the tubes. 3.8.7 Tube-in-Tube. A liquid cooler which consists of one or more assemblies of two tubes, one within the other, in which heat is transferred between the fluid in the inner tube or t
27、ubes and the fluid flowing between the inner and outer tubes. 3.9 “Shall“ or “Should.“ “Shall“ or “should“ shall be interpreted as follows: 3.9.1 Shall. Where “shall“ or “shall not“ is used for a provision specified, that provision is mandatory if compliance with the standard is claimed. 3.9.2 Shoul
28、d. “Should“ is used to indicate provisions which are not mandatory but which are desirable as good practice. 3.10 Superheat. The amount of temperature increase of the refrigerant above its saturation temperature at the exit of the liquid cooler. Copyright Air-Conditioning and Refrigeration Institute
29、 Provided by IHS under license with ARI Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-ARI STANDARD 480-2007 3 Section 4. Test Requirements 4.1 Test Requirements. All Standard Ratings shall be verified by tests conducted in accordance with ASHRAE Standard 24. Sect
30、ion 5. Rating Requirements 5.1 Standard Ratings. Published Ratings shall include the Standard Rating, as specified, for at least one of the Standard Rating Conditions shown in Table 1 and properly identified as the Standard Rating. Standard Ratings shall be based on tests with initially clean tubes.
31、 The liquid-side and refrigerant-side Fouling Factors shall be assumed to be zero. Table 1. Standard Rating Conditions Entering Liquid Temperature Leaving Liquid Temperature Saturated Refrigerant Temperature Leaving the Evaporator Liquid Refrigerant Entering Expansion Device Rating Condition Liquid
32、Being Cooled F C F C F C F C 1 2 3 Water 30% Ethylene Glycol Water 54 20 68 12 -6.7 20 44 15 60 6.7 -9.4 16 35 5.0 43 1.7 -15 6.1 100 100 110 37.8 37.8 43.3 Note: Ratings are for single component and azeotropic refrigerants only. Zeotropic refrigerants are excluded. The minimum Superheat of the leav
33、ing refrigerant shall be specified by the manufacturer. For water-source heat pump application only. 5.2 Application Ratings. Application Ratings provide performance data at operating conditions other than those shown in Table 1. Whenever Application Ratings are published or printed, they shall incl
34、ude, or be accompanied by, the Standard Rating, clearly designated as such, including a statement of the conditions at which the ratings apply. Application Ratings shall contain all information shown in 6.2. When Application Ratings include a water-side Field Fouling Allowance they shall be calculat
35、ed by the method specified in 5.3. Published Ratings shall be subject to the tolerances of this standard. 5.2.1 Either Application Ratings or a method of adjusting the clean tube ratings may be presented to show the effect of various liquid-side Field Fouling Allowances. These calculation methods or
36、 method of adjusting these ratings shall be calculated in accordance with 5.3. 5.2.2 The manufacturer shall publish the maximum and minimum recommended liquid flow rates. 5.3 Determination of Ratings. Ratings shall be determined in accordance with the following: 5.3.1 Clean Tube Ratings. Clean tube
37、ratings shall be based on tests with initially clean tubes conducted in accordance with 4.1. The results of these tests shall be accepted as reflecting a Fouling Factor of zero. 5.3.2 Fouled Tube Ratings. From the results of the clean tube tests, calculate the clean tube overall heat transfer coeffi
38、cient, Uc. Then, mathematically add the specified Fouling Factor to the reciprocal of Ucand calculate the fouled tube ratings for publication using the following method (refer to ARI Guideline E for discussion of Fouling Factors). cc(LMTD)q=UA (1) where: Copyright Air-Conditioning and Refrigeration
39、Institute Provided by IHS under license with ARI Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-ARI STANDARD 480-2007 4 we s wl swe sw1 stt( - )-( - )ttttLMTD ( - )ttln - =we wlwl s we wlw1 stt( - )tt= ( - ) + ( - )tt ttln - RLMTD = ln (1 + R/S)(2) The following e
40、quations shall be used to calculate the fouled tube ratings: 5.3.2.1 For fouling inside tubes (evaporating outside): a. Based on outside surface: cofoofiir1U = 1A+ UA(3a) b. Based on inside surface: fificiUUr1= 1+ (3b) 5.3.2.2 For fouling outside tubes (evaporating inside): a. Based on outside surfa
41、ce: fofoco1U = 1+rU(3c) b. Based on inside surface: fiifocioAA1U = 1+rU(3d) 5.3.2.3 The following equations shall be used for all configurations to obtain the small temperature difference, Sf, at the fouled condition: a. Based on outside surface: fxRS = - 1e(4a) Copyright Air-Conditioning and Refrig
42、eration Institute Provided by IHS under license with ARI Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-ARI STANDARD 480-2007 5 where: fo oRU Ax = qb. Based on inside surface: fyRS = - 1e(4b) where: fi iRU Ay = q5.3.2.4 The new evaporating temperature with fouled
43、tubes, tsf, can then be found using the small difference, Sf: w1 fsf= - tSt (5) 5.4 Symbols and Subscripts. The symbols and subscripts used in Equations 1 through 5 are as follows: Symbols: A = Total heat transfer surface area, ft2m2 Ai/Ao= Ratio of inside to outside surface area Ao/Ai= Ratio of out
44、side to inside surface area e = Base of natural logarithm LMTD = Logarithmic mean temperature difference, F C q = Net Refrigerating Capacity, Btu/h W r = Heat transfer resistance, h ft2 F/Btu m2 C/W R = Liquid temperature range = twe- twl, F C S = Small temperature difference = twl- ts, F C t = Temp
45、erature, F C U = Overall heat transfer coefficient, Btu/h ft2 F W/m2 C Subscripts: c = Clean e = Entering f = Fouled or fouling i = Inside l = Leaving o = Outside s = Saturated vapor leaving the evaporator w = Liquid 5.5 Tolerance. To comply with this standard, measured test results shall not be les
46、s than 95% of the Published Rating for Net Refrigerating Capacity and shall not exceed 110% of the Published Ratings for pressure drop. Copyright Air-Conditioning and Refrigeration Institute Provided by IHS under license with ARI Not for ResaleNo reproduction or networking permitted without license
47、from IHS-,-,-ARI STANDARD 480-2007 6 Section 6. Minimum Data Requirements for Published Ratings 6.1 Minimum Data Requirements for Published Ratings. As a minimum, Published Ratings shall include all Standard Ratings. All claims to ratings within the scope of this standard shall be accompanied by the
48、 statement “Rated in accordance with ARI Standard 480.” All claims to ratings outside the scope of this standard shall be accompanied by the statement “Outside the scope of ARI Standard 480.” Wherever Application Ratings are published or printed, they shall include a statement of the conditions at which the ratings apply. Application Ratings shall contain all information shown in 6.2. When Application Ratings include a liquid-side Fouling Factor, they shall be calculated by the method specified in 5.3. 6.2 Published Ratings 6.2.1 Publis
