ASHRAE 22-2007 Methods of Testing for Rating Water-Cooled Refrigerant Condensers《水冷式冷冻冷凝器额定值测试方法》.pdf

1、ASHRAE STANDARDAmerican Society of Heating, Refrigeratingand Air-Conditioning Engineers, Inc.1791 Tullie Circle NE, Atlanta, GA 30329www.ashrae.orgMethods of Testing forRating Water-CooledRefrigerantCondensersANSI/ASHRAE Standard 22-2007(Supersedes ANSI/ASHRAE Standard 22-2003)Approved by the ASHRAE

2、 Standards Committee on June 23, 2007; by the ASHRAE Board of Directors on June 27,2007; and by the American National Standards Institute on June 28, 2007.ASHRAE Standards are scheduled to be updated on a five-year cycle; the date following the standard number isthe year of ASHRAE Board of Directors

3、 approval. The latest copies may be purchased from ASHRAE CustomerService, 1791 Tullie Circle, NE, Atlanta, GA 30329-2305. E-mail: ordersashrae.org. Fax: 404-321-5478. Tele-phone: 404-636-8400 (worldwide) or toll free 1-800-527-4723 (for orders in US and Canada). Copyright 2007 ASHRAE, Inc.ISSN 1041

4、-2336www.ansi.orgASHRAE Standard Project Committee 22 Cognizant TC: TC 8.5, Liquid-to-Refrigerant Heat Exchangersc=K=pI=ChairGArthur G. Fovargue*Harold B. Ginder* Robert R. Miller*Joesph T. Pearson*Denotes members of voting status when the document was previously approved for publicationASHRAE STAND

5、ARDS COMMITTEE 20062007David E. Knebel, ChairStephen D. Kennedy, Vice-ChairMichael F. BedaDonald L. BrandtSteven T. BushbyPaul W. CabotHugh F. CrowtherSamuel D. Cummings, Jr.Robert G. DoerrRoger L. HedrickJohn F. HoganEli P. Howard, IIIFrank E. JakobJay A. KohlerJames D. LutzCarol E. MarriottMerle F

6、. McBrideMark P. ModeraRoss D. MontgomeryH. Michael NewmanStephen V. SantoroLawrence J. SchoenStephen V. SkalkoBodh R. SubherwalJerry W. White, Jr.James E. WoodsRichard D. Hermans, BODExOHugh D. McMillan, III, COClaire B. Ramspeck, Assistant Director of Technology for Standards and Special ProjectsS

7、TANDARDS REAFFIRMATION SUBCOMMITTEE 20062007*James Lutz, ChairMichael BedaSteven BushbyR. Michael MartinBodh SubherwalJames Woods*For the 2007 revision in which minor changes were performed(i.e., updating references), SRS acted as the consensus project committeeSPECIAL NOTEq=k=p=EkpF=p=eI=o=J=b=Epeo

8、bFK=Consensus=k=pf=EkpfFI=peob=kpI=applelogo=K=q=I=K=I=K=Kpeob=I=I=Kpeob=p=m=pK=q=m=sJ=peobX=peob=I=pK=b=mK=q=a=q=p=p=m=peob=WK=pIK=pIK=pI=K=pKDISCLAIMERpeob=p=d=K=eI=peob=I=I=I=I=I=I=peob=p=d=p=d=KASHRAE INDUSTRIAL ADVERTISING POLICY ON STANDARDSpeob=p=d=I=I=I=K=q=peob=p=d=I=Kf=p=d=I=I=I=peobKCONTE

9、NTSANSI/ASHRAE Standard 22-2007Methods of Testing for Rating Water-Cooled Refrigerant CondensersSECTION PAGEcKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKK ON=mKKKKKKKKKKKKKKKKKKKKKKK

10、KKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKK OO=p KKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKK OP=a=

11、qKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKK OQ=b=q=oKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKK OR=q=jKKKKKKKKKKKKKKKKKKKK

12、KKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKK OS=f=q= KKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKK QT=q=mKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKK

13、KKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKK RU=oKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKK SNOTEWhen addenda, interpretations, or errat

14、a to this standard have been approved, they can be downloadedfree of charge from the ASHRAE Web site at http:/www.ashrae.org. Copyright 2007 American Society of Heating,Refrigerating and Air-Conditioning Engineers, Inc.1791 Tullie Circle NEAtlanta, GA 30329www.ashrae.orgAll rights reserved.2 ANSI/AS

15、HRAE Standard 22-2007(This foreword is not part of this standard. It is merelyinformative and does not contain requirements necessaryfor conformance to the standard. It has not beenprocessed according to the ANSI requirements for astandard and may contain material that has not beensubject to public

16、review or a consensus process.Unresolved objectors on informative material are notoffered the right to appeal at ASHRAE or ANSI.)FOREWORDThis is a revision of ASHRAE Standard 22-2003.This standard prescribes methods for testing water-cooled refrigerant condensers. To attain this objective, thestanda

17、rd lists and defines the terms suggested for ratingwater-cooled refrigerant condensers and establishes testingmethods that may be used as a basis for obtaining ratings ofwater-cooled refrigerant condensers.This standard was prepared under the auspices of theAmerican Society of Heating, Refrigerating

18、 and Air-Condi-tioning Engineers (ASHRAE). It may be used, in whole orin part, by an association or government agency with duecredit to ASHRAE. Adherence is strictly on a voluntarybasis and merely in the interests of obtaining uniform stan-dards throughout the industry.The changes made for the 2007

19、revision were that the ref-erences were updated.1. PURPOSEThis standard prescribes methods of testing the thermalperformance of water-cooled refrigerant condensers.2. SCOPETo attain this objective, this standarda. lists and defines the terms suggested for the rating ofwater-cooled refrigerant conden

20、sers andb. establishes methods of test that can be used as a basisfor obtaining ratings of water-cooled refrigerant con-densers.3. DEFINITION OF TERMScondensing heat rejection (qc): the portion of the total heatrejection of a condenser that is used for desuperheating andcondensing the entering refri

21、gerant vapor to a saturated liq-uid. This is the product of the mass rate of refrigerant flow(wr) and the difference between the enthalpy of the enteringrefrigerant vapor and that of the saturated refrigerant liquid atthe leaving pressure.subcooling heat rejection (qs): the total heat rejection minu

22、sthe condensing heat rejection. This is the product of the massrate of refrigerant flow (wr) and the difference between theenthalpy of a saturated refrigerant liquid at the pressure of theleaving refrigerant and that of the refrigerant liquid at theactual leaving temperature.total heat rejection (qt

23、): the total useful capacity of a water-cooled refrigerant condenser for removing heat from therefrigerant circulated through it. This is the product of themass rate of refrigerant flow (wr) and the difference ofenthalpy of the entering and leaving refrigerant fluid.water-cooled refrigerant condense

24、r: a factory-made assem-bly of elements by which the flows of refrigerant vapor andwater are maintained in such a heat transfer relationship thatthe refrigerant vapor is condensed into a liquid.4. EXPRESSION OF TEST RESULTS4.1 Terms Recommended for Expressing Test Results4.1.1 In expressing test res

25、ults, the following factorsshould be stated:a. condensing heat rejection (qc), Btu/h (kW),b. subcooling heat rejection (qs), Btu/h (kW),c. saturated temperature of entering refrigerant vapor, F (C),d. temperature of entering water, F (C),e. water mass flow rate (ww), lbm/h (kg/s), andf. water pressu

26、re drop through condenser, psi (kPa).5. TEST METHODS5.1 Standard Test Methods5.1.1 Tests shall consist of a primary test and a simulta-neous confirming test at the conditions specified.5.1.2 Specified conditions will includea. either the total heat rejection, Btu/h (kW), or the satu-rated temperatur

27、e of entering refrigerant vapor, F (C),b. temperature of entering water, F (C),c. water mass flow rate, lbm/h (kg/s),d. minimum superheat of entering vapor, R (K),e. minimum ambient temperature, F (C),f. subcooling, F (C), andg. refrigerant used.5.1.3 The results of the confirming test shall be with

28、in 3%of the primary test, but the primary test shall govern for ratingpurposes.5.1.4 Refrigerant flow through the condenser shall be pro-duced by one of the following means (see Figures 1a and 1b):a. refrigerating compressor and low-side evaporator orcalorimeter (preferred method) orb. refrigerant b

29、oiler.5.2 Primary Test Methods5.2.1 The primary test for closed condensers (seeFigure 2) shall consist of determination of the heat rejectedfrom the refrigerant by a. measurement of heat rejected to the water andb. calculation of heat rejected through the external sur-faces of the condenser to the a

30、mbient air.ANSI/ASHRAE standard 22-2007 35.2.2 The heat rejected from the refrigerant to the water isthe product of the water flow rate and the enthalpy differenceof the leaving and entering water.5.2.3 The water flow rate shall be determined by use of awater quantity meter, water flow meter, or wei

31、gh tank.5.2.4 The enthalpy difference between the leaving andentering water shall be determined from temperature mea-surements.5.2.5 The heat rejected through the external surfaces to theambient air shall be determined by (1)whereqL= heat rejected through external surfaces, Btu/h (kW);Us = ; (2)x/k=

32、 0 if insulation is not used;x = insulation thickness, in. (m);k = thermal conductivity of insulation, Btuin./hft2F (W/m2C);hs= film coefficient of ambient air, Btu/hft2F(W/ m2C) for natural convection, usehs= 2.0 Btu/hft2F (11 W/(m2C);As= exposed external surface through which heat is lost, ft2(m2)

33、;tc= saturated condensing temperature, F (C); andta= average ambient air temperature, F (C).5.2.6 The heat rejected through the external surfaces ofthe condenser shall not exceed 3% of the heat rejected to thewater.5.2.7 For shell-and-tube, open-type condensers where theprimary method cannot be carr

34、ied out, the heat rejection shallbe measured by two of the confirming tests in accordancewith Section 5.3.5.3 Confirming Test Methods5.3.1 The confirming test shall consist of a secondarymeasurement of the heat rejected from the refrigerant byusing one of the optional methods described in Sections 5

35、.3.2,5.3.3, and 5.3.4 below (see also Figure 3).5.3.2 Condenser Refrigerant Side. This method deter-mines condenser heat rejection by calculating the product ofthe enthalpy difference of refrigerant fluid entering and leav-ing the condenser and the mass rate of refrigerant flow. Massrate of refriger

36、ant flow shall be determined by using one of thefollowing:a. A refrigerant flow-measuring instrument.b. A water or brine cooler arranged such that the refriger-ant mass flow rate is the same in the condenser and thecooler. The cooler shall be insulated if necessary suchthat the calculated heat gains

37、 through external surfacesdo not exceed 3% of the heat removed from water orbrine. The mass rate of refrigerant flow is obtained bydividing the cooler heat input, including leakage gains,by the enthalpy difference between entering and leav-ing refrigerant.qLUsAstcta()=1xk 1 hs+-Figure 1 Methods of p

38、roducing refrigerant flow through condenser.Figure 2 Primary test method.4 ANSI/ASHRAE Standard 22-2007c. A refrigerant calorimeter that provides a means ofaccurately measuring the amount of heat required toevaporate and superheat the refrigerant fluid flowingthrough it. The rate of refrigerant flow

39、 is given bydividing the heat input, including leakage gains, by theenthalpy difference of the entering and leaving refrig-erant fluid.5.3.3 Refrigerant Boiler. This method determines con-denser heat rejection as the heat needed to evaporate the liq-uid refrigerant in the boiler when this apparatus

40、is used inplace of a complete refrigerating system, as allowed in Sec-tion 5.1.4(b).5.3.4 Energy Balance Method. This method determinescondenser heat rejection using an energy balance on the entirerefrigerating system. It may be used if the following condi-tions are met:a. the condenser is installed

41、 in a closed refrigerant circuitserved by a water-heated evaporator and a hermetic orsemihermetic electric motor-compressor powered by asinusoidal single-phase or three-phase electric powersupply;b. the compressor and evaporator are closely matched incapacity to the condenser;c. no means of compressor cool