GB/T 10870-2014The methods of performance test for water chilling (heat pump) packages using the vaper compression cycle (English PDF)

1 Scope

GB/T 10870-2014 is the Chinese national standard on the methods of performance test for water chilling (heat pump) packages using the vaper compression cycle, in the field of energy and heat transfer engineering. The /T suffix marks it as a recommended standard: it is not compulsory by itself, but it becomes binding as soon as a contract, a tender or a customer specification calls it up - which in practice is how most foreign buyers meet it. It was issued on 24 June 2014 by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China; Standardization Administration of China, and has been in force since 31 December 2014. Classification: ICS 27.200, CCS J73. This page is published from the official record of the standard held by the Chinese standards administration: the identification, the dates, the classification and the issuing body are taken from there. The clause text, the tables and the numeric limits are in the document itself, which is delivered complete in English translation.

This standard specifies the terms and definitions, test provisions, test methods, test deviations, gross electric power, evaluation of performance coefficients, etc. of the main performance parameters of chilling water (heat pump) packages driven by electric motors using vapor compression refrigeration cycles. This standard applies to the performance test of chilling water (heat pump) packages (hereinafter referred to as "packages") driven by electric motors that use vapor compression refrigeration cycles. The cooling tower integrated package, brine package, glycol package, etc. can be implemented with reference to this standard.

2 Normative references

The following documents are essential to the application of this document. For the dated documents, only the versions with the dates indicated are applicable to this document; for the undated documents, only the latest version (including all the amendments) is applicable to this standard.

GB/T 2624.1 Measurement of fluid flow by means of pressure differential devices inserted in circular cross-section conduits running full - Part 1: General principles and requirements

GB/T 2624.2 Measurement of fluid flow by means of pressure differential devices inserted in circular cross-section conduits running full - Part 2: Orifice plates

GB/T 2624.3 Measurement of fluid flow by means of pressure differential devices inserted in circular cross-section conduits running full - Part 3: Nozzles and Venturi nozzles

GB/T 2624.4 Measurement of fluid flow by means of pressure differential devices inserted in circular cross-section conduits running full - Part 4: Venturi tubes Under the specified heating capacity test conditions, the ratio of the package's heating capacity to the gross electric power of heating, expressed in W/W.

9 Example of performance uncertainty analysis

Refer to Appendix E for an example of uncertainty analysis of heating performance measurement of water-cooled packages. a Applicable to the heating mode of the heat pump, except for the defrosting process and the first 10 minutes after the end of the defrosting. b Applicable to the heat pump's defrosting process and the first 10 minutes after the defrosting. A.4 Heating capacity test results A.4.1 Calculation of steady-state heating capacity A.4.1.1 Use the average heating value recorded in 35 minutes of the data collection stage as the average heating value. A.4.1.2 Use the average input power recorded in 35 minutes or the integrated input power recorded in 35 minutes during the data acquisition stage as the average input power. A.4.2 Calculation of non-steady-state heating capacity A.4.2.1 For the data collection period, if one or more complete cycles are included, the average heating capacity of the package shall be determined by the integrated heating capacity and all the time included in the data collection period; the average input electric power shall be determined by the integrated input power and the time which is same as the measured heating capacity in the data collection stage.

Note: A complete cycle includes a heat pump heating process and a defrosting process from the end of the defrost to the end of the next defrost. A.4.2.2 For a complete cycle that does not occur during the data collection period, the average heating capacity of the package shall be determined by the integrated heating capacity and the occurrence time during the data collection period; the average input electric power shall be determined by the integrated input power and the time which is same as the measured heating capacity in the data collection stage. A.5 Example diagram of heating performance test process during defrosting A.5.1 All examples include a case where a defrost cycle is used to end the pretreatment stage. The data collection cycle of the non-steady state test needs to last 3 hours or 3 complete cycles. A.5.2 Example diagrams of heating performance test process during defrosting are as shown in Figure A.1 ~ Figure A.6.

Appendix B

(Normative) Air inlet temperature measurement of air-cooled and evaporative-cooled chilling water (heat pump) packages B.1 Overview This Appendix specifies the measurement method of the air inlet temperature of air-cooled and evaporative-cooled chilling water (heat pump) packages; meanwhile specifies the air inlet temperature distribution requirements of the package during the test of this type of package. B.2 Definition B.2.1 Air sampler The air sampler is an air sampling tube assembly that extracts air through the sampling tube, to provide a uniform air sample entering the air-cooled heat exchange coil. B.2.2 Temperature and humidity measuring box The temperature and humidity measuring box is a device connected with an air sampler, to install a probe for measuring air temperature and humidity. B.3 General requirements B.3.1 The temperature measuring instrument and its accuracy shall meet the requirements of Appendix C. B.3.2 The test chamber and the test device shall be reasonably designed and operated, to ensure sufficient air distribution and sufficient air mixing. B.3.3 The test environment shall avoid the recirculation of the exhaust air of the air-cooled heat exchanger coil of the package. The following methods can be used to check whether the exhaust air of the heat exchanger is recycled back to the heat exchanger coil: install multiple single reading thermocouple evenly around the exhaust outlet of the package (at least one for each sampling position), the installed thermocouple is located below the air-cooled heat exchange coil fan's exhaust plane and just over the top of the air-cooled heat exchanger coil. The difference between the temperature of these thermocouples and the temperature measured at the temperature and humidity measuring box shall not exceed 2.8 °C. Celsius (°C); tw2,c - The temperature of the water outlet on the heat source side, in degrees Celsius (°C); P0 - The input power of the compressor motor, oil pump motor, electric heater, etc. of the water-cooled package, in watts (W); U(Qnc) - The expanded uncertainty of the package's cooling capacity measured in the verification test; k - Inclusion factor; u7 - Category A standard uncertainty component as caused by repeated measurement of verification test; u8 - Category B standard uncertainty component of the flow test system in the verification test; u9 - The category B standard uncertainty component of the inlet water temperature test system in the verification test; u10 - The category B standard uncertainty component of the outlet water temperature test system in the verification test; u11 - Standard uncertainty of input power. E.2 Evaluation of standard uncertainty components E.2.1 Category A evaluation of standard uncertainty components Carry out no less than 7 independent repeated measurements on the tested water chilling package; the measurement data (example values) are as shown in Table E.1. E.2.2.1 Overview Based on the average value of each measurement, calculate the sensitivity coefficients, then obtain the measurement uncertainty components. E.2.2.2 Uncertainty components of main test measurement parameters The sensitivity coefficient c2 is 20869 kJ/m3; the uncertainty given by the verification/calibration certificate is 0.1%FS (example value); then it obtains u2 = 3 × 10-5 m3/s, then the uncertainty component of the flow of the main test is c2u2 =

0.626 kW. The sensitivity coefficient c3 is

60.86 kW/K; the uncertainty given by the verification/calibration certificate is u3 =

0.03 K (example value); then the uncertainty component of the inlet water temperature of the main test is c3u3 =

1.757 kW. The sensitivity coefficient c4 is -

60.86 kW/K; the uncertainty given by the verification/calibration certificate is u4 =

0.03 K (example value); then the uncertainty component of the outlet water temperature of the main test is c4u4 = -

1.757 kW. E.2.2.3 Category B standard uncertainty of input power The maximum allowable error of the power meter is ±0.5% (example value). Considering the uniform distribution, the category B standard uncertainty of the input power is: E.2.2.4 Uncertainty components of measurement parameters in the verification test The sensitivity coefficient c8 is 20635 kJ/m3; the uncertainty given by the verification/calibration certificate is 0.1%FS (example value), so it obtains the standard uncertainty u8 = 3 × 10-5 m3/s; then the uncertainty component of flow rate of the calibration test is c8u8 =

0.619 kW. The sensitivity coefficient c9 is -

72.67 kW/K; the uncertainty given by the verification/calibration certificate is u9 =

0.03 K (example value); then the uncertainty component of the inlet water temperature in the verification test is c9u9 = -

2.181 kW. The sensitivity coefficient c10 is

72.67 kW/K; the uncertainty given by the verification/calibration certificate is u10 =

0.03 K (example value), then the uncertainty component of the outlet water temperature in the verification test is c10u10 =