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1、AS/NZS 4776.1.1:2008 Australian/New Zealand Standard Liquid-chilling packages using the vapour compression cycle Part 1.1: Method of rating and testing for performanceRating AS/NZS 4776.1.1:2008 AS/NZS 4776.1.1:2008 This Joint Australian/New Zealand Standard was prepared by Joint Technical Committee
2、 ME-086, Commercial Airconditioning Equipment. It was approved on behalf of the Council of Standards Australia on 9 September 2008 and on behalf of the Council of Standards New Zealand on 19 September 2008. This Standard was published on 14 November 2008. The following are represented on Committee M
3、E-086: Airconditioning however, it is not intended for field testing. Acknowledgment is due to the Air-Conditioning, Heating, and Refrigeration Institute (AHRI) of the USA, whose Standards were reviewed during the development of this Standard. This Standard is a Joint Australian/New Zealand Standard
4、 and is not an AHRI Standard. Statements expressed in mandatory terms in notes to figures are deemed to be requirements of this Standard. The terms normative and informative have been used in this Standard to define the application of the appendix to which they apply. A normative appendix is an inte
5、gral part of a Standard, whereas an informative appendix is only for information and guidance. 3 AS/NZS 4776.1.1:2008 CONTENTS Page 1 SCOPE4 2 OBJECTIVE .4 3 NORMATIVE REFERENCES .4 4 DEFINITIONS4 5 RATING REQUIREMENTS 6 6 PUBLISHED RATINGS.8 7 RATING TOLERANCES.10 AS/NZS 4776.1.1:2008 4 COPYRIGHT S
6、TANDARDS AUSTRALIA/STANDARDS NEW ZEALAND Australian/New Zealand Standard Liquid-chilling packages using the vapour compression cycle Part 1.1: Method of rating and testing for performanceRating 1 SCOPE This Standard sets out a procedure for rating liquid-chilling packages used in applications with t
7、emperatures as described in Clause 5.3 and as defined in Clause 4.12. This Standard covers air- and water-cooled liquid-chilling packages of cooling capacity 350 kW and above. This Standard does not cover (a)liquid-chilling packages driven by other than electric motors; (b)air-cooled liquid-chilling
8、 packages with centrifugal fans; (c)liquid-chilling packages with remote condensers; and (d)liquid-chilling packages for fluids other than water. This Standard covers full-load and part-load ratings to allow for an energy analysis of the unit in different applications. 2 OBJECTIVE The objective of t
9、his Standard is to establish methods of rating the performance of factory- made liquid-chilling packages using the vapour compression cycle. 3 NORMATIVE REFERENCES The following referenced documents are indispensable for the application of this Standard: AS/NZS 1677 Refrigerating systems 1677.1 Part
10、 1: Refrigerant classification ARI 550/590 Water chilling packages using the vapor compression cycle 4 DEFINITIONS For the purpose of this Standard, the definitions below apply. 4.1 Air-cooled condenser A refrigeration system component that condenses refrigerant vapour by rejecting heat to air circu
11、lated over its heat transfer surface, causing a rise in the air temperature. Desuperheating and subcooling of the refrigerant may occur as well. 4.2 Bubble point The saturation temperature of the refrigerant liquid at a specified pressure (C). 5 AS/NZS 4776.1.1:2008 COPYRIGHT 4.3 Coefficient of perf
12、ormance (COP) A ratio of the cooling capacity, in kW, to the total power input (as defined in Clause 4.16), in kW (kW/kW), which represents the efficiency of the liquid-chilling package at specific rating conditions. 4.4 Condenser heat rejection capacity The heat removed by the heat transfer medium
13、of the condenser per unit of time (kW). 4.5 Cooling capacity The heat given off from the liquid to the refrigerant per unit of time (kW). 4.6 Dew point The saturation temperature of the refrigerant vapour at a specified pressure (C). 4.7 Evaporator A heat transfer device that utilizes refrigerant-to
14、-liquid heat transfer means, causing the refrigerant to evaporate and the liquid to be cooled. Superheating of the refrigerant may occur as well. 4.8 Fouling factor The thermal resistance due to fouling accumulated on the fluid side of the heat transfer surface (m2.K/kW). 4.9 Fouling factor allowanc
15、e Provision for anticipated fouling during use (m2.K/kW). 4.10 Liquid-chilling package A factory-made and prefabricated assembly (not necessarily shipped as one package) of one or more compressors, condensers and evaporators, with interconnections and accessories, designed for the purpose of cooling
16、 water. It is a machine specifically designed to make use of a vapour compression refrigeration cycle to remove heat from water and reject the heat to a cooling medium, usually air or water. 4.11 Liquid-cooled condenser A heat transfer device that utilizes refrigerant-to-liquid heat transfer means,
17、causing the refrigerant to condense and the liquid to be heated. Desuperheating and subcooling of the refrigerant may occur as well. 4.12 Liquid refrigerant temperature The temperature of the refrigerant entering the expansion device (C). 4.13 Part-load value (PLV) A single number figure expressing
18、the part-load efficiency of liquid-chilling packages on the basis of weighted average operation at various partial load capacities and specific ambient conditions. 4.14 Part-load value, integrated (IPLV) A single number part-load efficiency figure for liquid-chilling packages calculated in accordanc
19、e with the method described in this Standard, at the standard rating conditions defined in Clause 5.2. 4.15 Part-load value, non-standard (NPLV) A single number part-load efficiency figure for liquid-chilling packages calculated in accordance with the method described in this Standard, at conditions
20、 other than the conditions defined in Clause 5.2. AS/NZS 4776.1.1:2008 6 COPYRIGHT 4.16 Saturated discharge temperature For single component and azeotropic refrigerants, the saturated temperature corresponding to the refrigerant pressure at the compressor discharge. For zeotropic refrigerants, the a
21、rithmetic average of the dew point and bubble point temperatures corresponding to refrigerant pressure at the compressor discharge. This temperature is usually taken at or immediately downstream of the compressor discharge service valve (in either case, on the downstream side of the valve seat), whe
22、re discharge valves are used (C). 4.17 Total power input The power input of all components of the unit in operation, which includes (a)the power input for operation of the compressor (kW); (b)the power input of all controls, safety devices, starters and drives of the unit, including devices necessar
23、y for correct operation of the refrigerating circuit (e.g. oil pump, refrigerant pump) (kW); and (c)the power for fans for air-cooled liquid-chilling packages (kW). 4.18Published ratings Performance data over the operating range of the unit at full load or part load in the form of a catalogue or out
24、put from a computer selection code. 5 RATING REQUIREMENTS 5.1 Test requirements All tests for liquid-chilling package ratings shall be conducted in accordance with AS/NZS 4776.1.2. 5.2 Standard rating conditions Published ratings for all liquid-chilling packages, as specified in Clause 6, shall incl
25、ude the standard ratings corresponding to the standard rating conditions shown in Tables 1 and 2 within the operating limits of the unit. 5.3 Application rating conditions Application ratings should include the following range of rating conditions or be within the operating limits of the equipment:
26、(a)All condenser types: Leaving chilled water temperature 4 to 9C. (b)Water-cooled condensers: Entering condenser water temperature .18 to 40C. (c)Air-cooled condensers: Entering condenser air dry-bulb temperature .13 to 52C. 5.4 Part-load rating Water-chilling packages that are capable of capacity
27、reduction shall be rated at 100% and at each step of capacity reduction provided by the refrigeration system(s) as published by the manufacturer. Part-load ratings points shall be based on the conditions defined in Table 2 for IPLV and NPLV. 7 AS/NZS 4776.1.1:2008 COPYRIGHT 5.5 Determination of part
28、-load performance For water-chilling packages covered by this Standard, the IPLV or NPLV shall be calculated as follows: (a)Determine the full-load and part-load energy efficiency at 100%, 75%, 50% and 25% load points under the conditions specified in Table 2. (b)Use the following equation to calcul
29、ate the IPLV or NPLV: 0.01A + 0.42B + 0.45C + 0.12D . . . (1) where A = COP at 100% load B = COP at 75% load C = COP at 50% load D = COP at 25% load NOTE: The part-load rating conditions are measured with the condenser relief conditions defined in Table 2. TABLE 1 STANDARD RATING CONDITIONS FOR COOL
30、ING Liquid-cooled Air-cooled Method 1 2 1 2 Liquid cooled condenser Entering temperature 30C 29.4C N/A N/A Delta T 5 K N/A N/A N/A Flow rate N/A 0.054 L/s/kWN/A N/A Liquid-side fouling factor allowance 0.044 m2 K/kW N/A N/A Air-cooled condenser Condenser coil entering dry-bulb temperature N/A N/A 35
31、C 35C Air-side fouling factor allowance N/A 0.000 m2 K/kW Evaporator liquid temperature 1 2 Leaving 7C 6.7C Delta T 5 K N/A Flow rate N/A 0.043 L/s/kW Liquid-side fouling factor allowance 0.018 m2 K/kW 0.018 m2 K/kW NOTE: Method 1 is according to the Eurovent Liquid Chilling Packages Certification P
32、rogramme; Method 2 is according to ARI 550/590. AS/NZS 4776.1.1:2008 8 COPYRIGHT TABLE 2 IPLV AND NPLV RATING CONDITIONS IPLV NPLV Evaporator LWT 100% load 6.7C Application LWT 0% load 6.7C Application LWT Flow rate 0.043 L/s/kW Application L/s/kW Fouling factor allowance 0.018 L/s/kW As specified W
33、ater-cooled condenser 100% load EWT 29.4C Application EWT 75% load EWT 23.9C See Note 50% load EWT 18.3C 18.3C 25% load EWT 18.3C 18.3C 0% load EWT 18.3C 18.3C Flow rate 0.054 L/s/kW Application L/s/kW Fouling factor allowance 0.044 m2 K/kW As specified Air-cooled condenser 100% load EDB 35.0C N/A 7
34、5% load EDB 26.7C N/A 50% load EDB 18.3C N/A 25% load EDB 12.8C N/A 0% load EDB 12.8C N/A Fouling factor allowance 0.000 m2 K/kW N/A LEGEND: LWT = leaving water temperature EWT = entering water temperature EDB = entering air dry-bulb temperature N/A = not applicable NOTE: EWTs vary linearly from EWT
35、 at 100% load to a minimum of 18.3C at 50% load. 6 PUBLISHED RATINGS 6.1 Compliance To comply with this Standard, performance ratings shall be based on test data or models derived from test data. Published ratings shall include the following: (a)Refrigerant in accordance with AS/NZS 1677.1. (b)Model
36、 number designations identifying the liquid-chilling packages to which the ratings shall apply. (c)Nominal voltage and frequency. 6.2 Fouling allowance Published ratings shall clearly state the fouling factor allowance. Corrections and calculations for different fouling factors shall be made. Rating
37、s shall be published using the nominal fouling factors as given in Tables 1 and 2. 9 AS/NZS 4776.1.1:2008 COPYRIGHT 6.3 Standard ratings The standard ratings shall include the following data: (a)For all units: (i)Total power input to liquid-chilling packages (kW). (ii)Cooling capacity (kW). (iii)Vol
38、tage (V). (iv)Frequency (Hz). (v)COP (kW/kW). (vi)IPLV (kW/kW). (vii) Any two of the following: (A)Entering evaporator liquid temperature (C). (B)Leaving evaporator liquid temperature (C). (C)Liquid temperature difference through the evaporator (K). (viii) For all units without an integral evaporato
39、r pump, the evaporator liquid pressure drop (kPa). For units with an integral evaporator pump, the available pump static pressure (kPa) in relation to water flow. (ix)Chilled liquid flow rate (L/s). (b)For liquid-cooled condenser packages: (i)For water-cooled units without an integral pump condenser
40、, the liquid pressure drop (kPa). For units with an integral pump condenser, the available pump static pressure (kPa) in relation to water flow. (ii)In addition, for all liquid-cooled condenser packages, any two of the following: (A)Entering condenser liquid temperature, (C). (B)Leaving condenser li
41、quid temperature, (C). (C)Liquid temperature difference through the condenser, (K). (D)Condenser liquid flow rate (L/s). (c)For air-cooled condenser units Dry-bulb temperature (C) of air entering the condenser coil. 6.4 Nameplate information As a minimum, the nameplate shall display the following in
42、formation: (a)Manufacturers name and location of manufacture. (b)Model number/designation allowing traceability of performance. (c)Refrigerant designation in accordance with AS/NZS 1677.1. (d)Voltage, phase and frequency. AS/NZS 4776.1.1:2008 10 COPYRIGHT 7 RATING TOLERANCES 7.1 General Ratings publ
43、ished and claimed to be in compliance with this Standard shall meet the allowable tolerance as specified in Clause 7.2. The full-load capacity and full-load and part-load COP values shall be not less than 100% of the rating less the allowable tolerance in Clause 7.2. The liquid pressure drop in the
44、evaporator or the condenser shall not exceed 115% of the rated pressure drop at the specified liquid flow rate under any rated condition. The pump head for units with integral pump(s) in the evaporator or the condenser shall be not less than 85% of the rated pump head at the specified liquid flow ra
45、te under any rated condition. 7.2 Allowable tolerance The full-load and part-load allowable tolerances on capacity (kW) and COP (kW/kW) shall be determined from the following equation: Allowable tolerance (as a percentage) = () + FLDT FL % 3 .833 %07 . 0 5 .10 FL where %FL = percentage of selected f
46、ull-load rating conditions DTFL = difference between entering and leaving chilled water temperature at full load (K) 7.3 Full-load example in COP Rated capacity = 500 kW Rated power input = 100 kW Cooling DTFL = 5 K 7.4 Part-load example in COP Assume a part load of 75% of the rated capacity. Part l
47、oad capacity = 375 kW Part load power input = 70 kW Cooling DTFL = 5 K 11 AS/NZS 4776.1.1:2008 NOTES AS/NZS 4776.1.1:2008 12 NOTES Standards Australia Standards Australia is an independent company, limited by guarantee, which prepares and publishes most of the voluntary technical and commercial stan
48、dards used in Australia. These standards are developed through an open process of consultation and consensus, in which all interested parties are invited to participate. Through a Memorandum of Understanding with the Commonwealth government, Standards Australia is recognized as Australias peak natio
49、nal standards body. Standards New Zealand The first national Standards organization was created in New Zealand in 1932. The Standards Council of New Zealand is the national authority responsible for the production of Standards. Standards New Zealand is the trading arm of the Standards Council established under the Standards Act 1988. Australian/New Zealand Standards Under a Memorandum of Understanding between Standards Australia and Standards New Zealand, Australian/New Zealand Stan
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