GB 8484-1987 Classification and testing methods of thermal insulation performance of building exterior windows

GB 8484-1987 Classification and test methods of thermal insulation performance of building exterior windows GB8484-1987 standard download decompression password: www.bzxz.net

Engineering Construction Standard Full-text Information System
UDC 69.028 : 69.058
National Standard of the People's Republic of China
GB8484—87
Graduation and test method for thermal insulating properties of windows Construction Standard
Published on December 18, 1987
Implementation on July 1, 1988
Published by the Ministry of Urban and Rural Construction and Environmental Protection of the People's Republic of China Engineering Construction Standard Full-text Information System
National Standard of the People's Republic of China
Graduation and test method for thermal insulating properties of windows 1 Subject content and scope of application
This standard specifies the grading and test method for thermal insulating properties of windows of buildings. UDC69.028:69.058
GB8484—87
This standard applies to the thermal insulation performance classification and test methods of building exterior windows (including skylights and the upper glass-inlaid parts of balcony doors, excluding the opaque parts of the lower balcony doors). 2 Reference standards
GB7107 Classification of air permeability performance of building exterior windows and its test methods 3 Definitions
3.1 Thermal insulation property: The ability of the window to transfer heat from the high-temperature side to the low-temperature side under the condition of air temperature difference on both sides of the window. The thermal insulation performance of the window is expressed by its heat transfer coefficient or heat transfer resistance. 3.2 Thermal transfer coefficient K (thermal transmittance): Under stable heat transfer conditions, the air temperature difference on both sides of the window is 1K, and the amount of heat transferred per unit area per unit time is measured in W/(m2·K). 3.3 Thermal resistance Ro (total thermal resistance): the reciprocal of the heat transfer coefficient, Ro = 1/K, measured in (m2·K)/W. 3.4 Thermal conductivity G (thermal conductance): under stable heat transfer conditions, the temperature difference between the two surfaces of the flat material is 1K, and the amount of heat transferred per unit area per unit time is measured in W/(m2·K). 4 Classification
4.1 Classification index: The window heat transfer coefficient K value or thermal resistance R value is used as the thermal insulation performance classification index. 4.2 Classification: The thermal insulation performance classification of windows is shown in Table 1. Table 1
Grading of window thermal insulation performance
Heat transfer coefficient K
W/(m2·K)
>2.00,<3.00
>3.00,≤4.00
>4.00,<5.00
>5.00,<6. 40
Approved by the Ministry of Urban and Rural Construction and Environmental Protection of the People's Republic of China on December 18, 1987 Heat transfer resistance Ro
(m2K)/w
<0.500,≥0.333
<0.333,≥0.250
<0.250,≥0.200
<0.200,≥0.156
Implemented on July 1, 1988
Engineering Construction Standard Full Text Information System
5 Test Method
5.1 This standard adopts the calibrated hot chamber method to test the thermal insulation performance of windows. 5.2 Principle of the method
5.2.1 This method is based on the principle of steady heat transfer. One side of the specimen is a hot chamber to simulate the indoor conditions of a heating building: the other side is a cold chamber to simulate the outdoor climate conditions. The gaps in the specimen are sealed to eliminate air infiltration through the gaps. The heat generated by the electric heater in the heat chamber is measured under stable air temperature, air flow velocity and thermal radiation conditions on both sides of the specimen. The heat generated minus the heat loss through the heat chamber wall and the specimen frame (both of which are determined by calibration tests) gives the heat transfer through the specimen. The heat transfer coefficient K of the specimen is obtained by dividing this heat transfer by the specimen area and the air temperature difference on both sides.
Note: In current calculations, the heat loss due to air infiltration through the window gap is usually considered separately from the heat loss due to heat transfer through the window. Therefore, when measuring the heat transfer coefficient of the window, the window gap should be sealed to eliminate the influence of air infiltration. 5.2.2 The heat transfer coefficient K value [W/(m2·K] of the specimen is calculated according to the following formula: K=2-M1· A,-M2 ·AO2
Where: Q
Heating power of electric heater, W;
Test piece area, calculated according to the outer edge size of the test piece, m; the difference between the temperature of the hot chamber and the temperature of the cold chamber te (△t=t-t), K△e1——the temperature difference between the inner and outer surfaces of the outer wall of the hot chamber, K; the temperature difference between the hot and cold surfaces of the test piece frame, K;
M1, M2——are the heat flow coefficients of the outer wall of the hot chamber and the test piece frame respectively determined by the calibration test, W/K. 5.3 Detection device
The detection device mainly consists of four parts: hot chamber, cold chamber, test piece frame and environmental space, as shown in Figure 1. 3
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1—hot chamber, 2—cold chamber, 3—test piece frame 4—electric heater, 5—test piece; 6—wind baffle; 7—axial flow fan; 8—evaporator; 9—cold chamber electric heater, 10—compression condensing unit, 11—air conditioner 5.3.1 Hot chamber
5.3.1.1 The opening size of the hot chamber is 2400×2400mm and the depth is 2000mm. (1)
5.3.1.2 The outer wall structure of the hot chamber should be uniform, and its thermal resistance value should be greater than 1.00 (m2·K)/W. The heat loss through the entire outer wall should be less than 10% of the heat transfer of the test piece.
5.3.1.3 The blackness e value of the inner surface of the hot chamber should be greater than 0.85. 5.3.1.4 Hot The room is heated by an electric heater, which is powered by an AC regulated power supply. The heating amount and air temperature are adjusted by a voltage regulator. The electric heater should be installed in the middle of the width of the specimen frame window sill to create natural air convection. The window sill should be at least 50mm higher than the top of the electric heater. Note: The structural form and surface temperature of the electric heater are similar to those of ordinary convection radiators, and its convection and radiation heat transfer conditions are close to actual use conditions. 5.3.2 Cold room
Engineering Construction Standard Full Text Information System
5.3.2.1 The opening size of the cold room should be the same as the outer edge size of the specimen frame, and the depth should be able to accommodate refrigeration, heating and airflow devices. 5.3.2.2 The thermal resistance of the outer wall of the cold room should be greater than 2.00 (m2·K)/W. 5.3.2.3 Cold room The chamber can be cooled by an evaporator placed in the cold room or by introducing cold air into the cold room. By controlling the temperature of the evaporator, the temperature of the cold room is lower than the set temperature. Then, the electric heater installed in the cold room is used to heat the cold room to the set temperature. 5.3.2.4 Use the wind baffle and three or more axial flow fans evenly arranged below it to create a uniform airflow from top to bottom along the surface of the specimen. The distance between the wind baffle and the surface of the specimen frame should be about 300mm. This distance should be adjustable to change the air flow velocity near the surface of the specimen.
5.3.2.5 The blackness 8 value of the surface of the wind baffle facing the specimen should be greater than 0.85. 5.3.2.6 A drainage hole or a water tray should be set at the bottom of the cold room evaporator to facilitate the removal of condensed water. 5.3.3 Specimen frame
5.3.3.1 The outer edge size of the specimen frame should be equal to or greater than the inner edge size at the opening of the hot chamber, and the thickness should be about 300mm. 5.3.3.2 The specimen frame shall be uniform in structure, and the thermal resistance shall be greater than 2.00 (m2·K)/W. 5.3.3.3 The size of the opening for installing the specimen is usually 1500mmX1500mm, which can be changed according to the size of the specimen if necessary. A window sill shall be left at the bottom of the opening. The window sill and the surrounding area of ​​the opening shall be made of wood or materials with a thermal conductivity of less than 0.25W/m·K). 5.3.4 Environmental space
5.3.4.1 The detection device shall be placed in a test room equipped with an air conditioner. The air conditioner shall ensure that the temperature difference between the inner and outer surfaces of the outer wall of the hot room is less than 1K. 5.3.4.2 The test room shall have good thermal stability, and the indoor air temperature fluctuation shall not exceed ±0.5℃, and direct sunlight shall be avoided from entering the room through the window.
5.3.4.3 At least 200mm of space shall be left between the outer wall of the hot room and the walls, floor and ceiling of the test room for air circulation. 5.4 Test piece and its installation
5.4.1 The size and structure of the test piece shall meet the product design and assembly requirements. Before testing, the glass shall be inlaid according to the design requirements and sealed if necessary.
5.4.2 Specimen installation position: The outer surface of the single-layer window and double-layer window specimens should be located 50mm away from the cold side surface of the specimen frame; the distance between the inner surface of the double-layer window specimen and the hot side surface of the specimen frame should be no less than 50mm. 5.4.3 The gap between the periphery of the specimen and the opening of the specimen frame should be filled with high-efficiency thermal insulation materials such as foam plastics, and sealing materials should be applied or pasted.
5.4.4 For specimens with air permeability performance level of IV and below, the open gap should be sealed with caulking materials or white adhesive tape; for specimens with air permeability performance level of sub-level and above, no sealing treatment is required. Note: For the classification of air permeability performance of building exterior windows, see GB7107. 5.5 Test conditions
5.5.1 The air temperature of the hot chamber is set to 18℃, and the temperature fluctuation should be less than or equal to 0.1℃. The air flow on the surface of the specimen is natural convection. 5.5.2 Cold room set air temperature: -10℃ for single-layer window testing, -20℃ for double-layer window or single-frame double-glazed window testing, temperature fluctuation should be less than or equal to 0.3℃. Set air flow velocity near the test piece surface is 3.0m/s. Note: Set temperature and air flow velocity refer to a stable temperature and air flow velocity near this value. 5.6 Calibration
5.6.1 Purpose: To determine the heat flux coefficients M1 and M2 of the outer wall of the hot chamber and the specimen frame through calibration tests. 5.6.2 Method: Place a standard specimen with known thermal conductivity at the position of the window specimen, conduct two tests under conditions close to the specimen test conditions, and then solve M1 and M2 by the following two equations: [Q-Mi·01-M2·02=A·G·△0s
[Q'-M· △1-M2·2-AG·
·..·(2)
**·(3)
wherein G and A are the thermal conductivity and area of ​​the standard specimen respectively; △91, △92 and △93 are the temperature differences between the outer wall of the hot chamber, the specimen frame and the standard specimen respectively; the symbols in equation (3) are the parameters corresponding to equation (2) in the second test. The two calibration tests shall be conducted under the condition that the air temperature difference on both sides of the specimen is the same or close, and the absolute values ​​of △1 and △1 are not less than 3K, the difference between △1 and △91 is not less than 6K, and △2 and △2 are as close or equal as possible.
5.6.3 Standard specimen
5.6.3.1 The standard specimen shall be made of uniform, airtight material, no air layer inside, and stable thermal performance. The size is 1500mmX1500mm. A 50mm thick semi-rigid polystyrene foam plastic board that has been stored for a long time can be used as the standard specimen. 5.6.3.2 The thermal conductivity G value of the standard specimen shall be measured according to the large flat plate method of one-way heat transfer heat protection plate under temperature difference conditions similar to those of the calibration test.
5.6.4 Calibration interval
5.6.4.1 The calibration test shall be conducted regularly, not less than once a year. 5.6.4.2 When the material, structure or opening size of the test piece frame is changed, it should be recalibrated. 5.7 Measurement
5.7.1 Electric heater heating power
5.7.1.1 The electric heater heating power Q[W is calculated according to the following formula: Q=IV
Where: I is the current passing through the heating wire of the electric heater, A; V is the voltage across the heating wire, V.
5.7.1.2 The current and voltage are measured with an AC ammeter and a voltmeter respectively. The instrument grade should not be lower than grade 0.5, and should be able to be greater than the conversion range according to the measured value, so that it is at more than 70% of the full range. 5.7.2 Temperature
5.7.2.1 The temperature is measured with a copper-constantan thermocouple with a wire diameter less than 0.4mm, and the measurement accuracy should not be lower than ±0.1℃. 5.7.2.2 Air temperature
a. The air temperature measurement points of the hot room should be evenly distributed in the hot room space, and the number of measurement points should not be less than 8 points. The measurement points should be about 500mm away from the wall.
b. The air temperature measurement points of the cold room should be arranged in a plane more than 100mm away from the surface of the specimen. 9 points are evenly arranged on the 1500mm×1500mm area corresponding to the hole. The arrangement position does not need to change with the change of the hole size. c. All air temperature probes should be equipped with shielding covers to avoid the influence of thermal radiation. d. The air temperature measurement points of the hot and cold rooms can be connected in parallel to measure their respective average temperatures. 5.7.2.3 Surface temperature
a. The number of points on each inner and outer surface of each outer wall of the hot room should not be less than 5. b. The number of points on each side of the hot and cold side surfaces of the specimen frame should not be less than 8. In the parts affected by the radiation of the electric heater, representative positions should be selected through tests for point arrangement.
c. The surface temperature measuring points should be arranged correspondingly and can be connected into thermocouples to directly measure the surface temperature difference. d. The surface temperature measuring points should be attached to the measured surface with adhesive materials together with at least 100mm long leads. The blackness e value of the adhesive material should be close to the measured surface.
e. The temperature measuring points on each surface of the hot chamber outer wall and the specimen frame can be connected in parallel to measure their respective average temperatures. When connected in parallel, the resistance of each thermocouple lead must be equal.
5.7.3 Wind speed and pressure difference
5.7.3.1 The wind speed in the cold chamber can be measured by a calibrated thermoelectric anemometer, and the measuring point position is the same as the cold air temperature measuring point. 5.7.3.2 The air pressure difference between the hot and cold chambers is measured by a compensated micromanometer. The measuring head should be placed in the middle of the hole height and not affected by the airflow. 5.7.3.3 Wind speed and pressure difference only need to be checked regularly and do not need to be measured every time. 5.8 Test Procedure
5.8.1 Install and seal the test piece according to the requirements of 5.4. W.bzsoso.cO Engineering Construction Standard Full Text Information System
5.8.2 Start the test device and control the temperature of the hot and cold rooms according to the requirements of 5.5. 5.8.3 When the temperature of the hot and cold rooms reaches the specified requirements and the heating power of the electric heater remains stable for 4 hours, start measuring various parameters. 5.8.4 When the hourly measured temperature of the hot room and the temperature difference between the inner and outer surfaces of the outer wall of the hot room △91 change less than or equal to 0.1K per hour, the temperature of the cold room t. and the temperature difference between the hot and cold surfaces of the test piece frame △92 change less than or equal to 0.3K per hour, and it is not a unidirectional change, it is considered to have entered a stable state.
5.8.5 After entering a stable state, measure t, t. and △01, △02 and Q once an hour. 5.8.6 Take the average of the four measurement results and calculate the heat transfer coefficient K value according to formula (1) or formula (5). 5.9 Test results
5.9.1 The heat transfer coefficient K value of single-layer window and single-frame double-glass specimens is calculated according to formula (1). 5.9.2 The heat transfer coefficient K value of double-layer window specimens is calculated according to the following formula: K=-M·A-(M2+AM)Ae2
（5）
Wherein, △M2 is the correction introduced due to the increase in specimen thickness. In this test device, △M2 is taken as 0.22W/K, and the other symbols are the same as formula (1).
5.9.3 When the specimen area is smaller than the opening size, a polystyrene foam board with the same thickness as the specimen should be used to seal the gap, and the heat loss through the board should be measured. When calculating the heat transfer coefficient K value of single-layer window and double-layer window specimens, this heat loss should be subtracted from the numerator of formula (1) and formula (5) respectively.
5.9.4 The calculation result shall be rounded to three significant figures. 5.10 Test report
The test report shall include the following contents:
a. Specimen number, source or entrusted unit. b. Specimen type and size, structural diagram, glass type and thickness, window frame material, window frame window opening area ratio, air permeability performance level and sealing treatment during installation.
c. Test conditions: hot room temperature, cold room temperature and air flow velocity. d. Test results: K, Q, t, te, △91, △92 and thermal insulation performance level. e. Signatures of the tester and the person in charge.
f. Name and address of the testing unit, stamped with the official seal and dated. Additional notes:
This standard is under the jurisdiction of the China Building Standard Design Institute. This standard was drafted and interpreted by the Institute of Building Physics of the China Academy of Building Research.3℃. The set airflow velocity near the test piece surface is 3.0m/s. Note: The set temperature and airflow velocity refer to a certain stable temperature and airflow velocity near this value. 5.6 Calibration
5.6.1 Purpose: To determine the heat flux coefficients M1 and M2 of the outer wall of the hot chamber and the specimen frame through calibration tests. 5.6.2 Method: Place a standard specimen with known thermal conductivity at the position of the window specimen, conduct two tests under conditions close to the specimen test conditions, and then solve M1 and M2 by the following two equations: [Q-Mi·01-M2·02=A·G·△0s
[Q'-M· △1-M2·2-AG·
·..·(2)
**·(3)
wherein G and A are the thermal conductivity and area of ​​the standard specimen respectively; △91, △92 and △93 are the temperature differences between the outer wall of the hot chamber, the specimen frame and the standard specimen respectively; the symbols in equation (3) are the parameters corresponding to equation (2) in the second test. The two calibration tests shall be conducted under the condition that the air temperature difference on both sides of the specimen is the same or close, and the absolute values ​​of △1 and △1 are not less than 3K, the difference between △1 and △91 is not less than 6K, and △2 and △2 are as close or equal as possible.
5.6.3 Standard specimen
5.6.3.1 The standard specimen shall be made of uniform, airtight material, no air layer inside, and stable thermal performance. The size is 1500mmX1500mm. A 50mm thick semi-rigid polystyrene foam plastic board that has been stored for a long time can be used as the standard specimen. 5.6.3.2 The thermal conductivity G value of the standard specimen shall be measured according to the large flat plate method of one-way heat transfer heat protection plate under temperature difference conditions similar to those of the calibration test.
5.6.4 Calibration interval
5.6.4.1 The calibration test shall be conducted regularly, not less than once a year. 5.6.4.2 When the material, structure or opening size of the test piece frame is changed, it should be recalibrated. 5.7 Measurement
5.7.1 Electric heater heating power
5.7.1.1 The electric heater heating power Q[W is calculated according to the following formula: Q=IV
Where: I is the current passing through the heating wire of the electric heater, A; V is the voltage across the heating wire, V.
5.7.1.2 The current and voltage are measured with an AC ammeter and a voltmeter respectively. The instrument grade should not be lower than grade 0.5, and should be able to be greater than the conversion range according to the measured value, so that it is at more than 70% of the full range. 5.7.2 Temperature
5.7.2.1 The temperature is measured with a copper-constantan thermocouple with a wire diameter less than 0.4mm, and the measurement accuracy should not be lower than ±0.1℃. 5.7.2.2 Air temperature
a. The air temperature measurement points of the hot room should be evenly distributed in the hot room space, and the number of measurement points should not be less than 8 points. The measurement points should be about 500mm away from the wall.
b. The air temperature measurement points of the cold room should be arranged in a plane more than 100mm away from the surface of the specimen. 9 points are evenly arranged on the 1500mm×1500mm area corresponding to the hole. The arrangement position does not need to change with the change of the hole size. c. All air temperature probes should be equipped with shielding covers to avoid the influence of thermal radiation. d. The air temperature measurement points of the hot and cold rooms can be connected in parallel to measure their respective average temperatures. 5.7.2.3 Surface temperature
a. The number of points on each inner and outer surface of each outer wall of the hot room should not be less than 5. b. The number of points on each side of the hot and cold side surfaces of the specimen frame should not be less than 8. In the parts affected by the radiation of the electric heater, representative positions should be selected through tests for point arrangement.
c. The surface temperature measuring points should be arranged correspondingly and can be connected into thermocouples to directly measure the surface temperature difference. d. The surface temperature measuring points should be attached to the measured surface with adhesive materials together with at least 100mm long leads. The blackness e value of the adhesive material should be close to the measured surface.
e. The temperature measuring points on each surface of the hot chamber outer wall and the specimen frame can be connected in parallel to measure their respective average temperatures. When connected in parallel, the resistance of each thermocouple lead must be equal.
5.7.3 Wind speed and pressure difference
5.7.3.1 The wind speed in the cold chamber can be measured by a calibrated thermoelectric anemometer, and the measuring point position is the same as the cold air temperature measuring point. 5.7.3.2 The air pressure difference between the hot and cold chambers is measured by a compensated micromanometer. The measuring head should be placed in the middle of the hole height and not affected by the airflow. 5.7.3.3 Wind speed and pressure difference only need to be checked regularly and do not need to be measured every time. 5.8 Test Procedure
5.8.1 Install and seal the test piece according to the requirements of 5.4. W.bzsoso.cO Engineering Construction Standard Full Text Information System
5.8.2 Start the test device and control the temperature of the hot and cold rooms according to the requirements of 5.5. 5.8.3 When the temperature of the hot and cold rooms reaches the specified requirements and the heating power of the electric heater remains stable for 4 hours, start measuring various parameters. 5.8.4 When the hourly measured temperature of the hot room and the temperature difference between the inner and outer surfaces of the outer wall of the hot room △91 change less than or equal to 0.1K per hour, the temperature of the cold room t. and the temperature difference between the hot and cold surfaces of the test piece frame △92 change less than or equal to 0.3K per hour, and it is not a unidirectional change, it is considered to have entered a stable state.
5.8.5 After entering a stable state, measure t, t. and △01, △02 and Q once an hour. 5.8.6 Take the average of the four measurement results and calculate the heat transfer coefficient K value according to formula (1) or formula (5). 5.9 Test results
5.9.1 The heat transfer coefficient K value of single-layer window and single-frame double-glass specimens is calculated according to formula (1). 5.9.2 The heat transfer coefficient K value of double-layer window specimens is calculated according to the following formula: K=-M·A-(M2+AM)Ae2
（5）
Wherein, △M2 is the correction introduced due to the increase in specimen thickness. In this test device, △M2 is taken as 0.22W/K, and the other symbols are the same as formula (1).
5.9.3 When the specimen area is smaller than the opening size, a polystyrene foam board with the same thickness as the specimen should be used to seal the gap, and the heat loss through the board should be measured. When calculating the heat transfer coefficient K value of single-layer window and double-layer window specimens, this heat loss should be subtracted from the numerator of formula (1) and formula (5) respectively.
5.9.4 The calculation result shall be rounded to three significant figures. 5.10 Test report
The test report shall include the following contents:
a. Specimen number, source or entrusted unit. b. Specimen type and size, structural diagram, glass type and thickness, window frame material, window frame window opening area ratio, air permeability performance level and sealing treatment during installation.
c. Test conditions: hot room temperature, cold room temperature and air flow velocity. d. Test results: K, Q, t, te, △91, △92 and thermal insulation performance level. e. Signatures of the tester and the person in charge.
f. Name and address of the testing unit, stamped with the official seal and dated. Additional notes:
This standard is under the jurisdiction of the China Building Standard Design Institute. This standard was drafted and interpreted by the Institute of Building Physics of the China Academy of Building Research.3℃. The set airflow velocity near the test piece surface is 3.0m/s. Note: The set temperature and airflow velocity refer to a certain stable temperature and airflow velocity near this value. 5.6 Calibration
5.6.1 Purpose: To determine the heat flux coefficients M1 and M2 of the outer wall of the hot chamber and the specimen frame through calibration tests. 5.6.2 Method: Place a standard specimen with known thermal conductivity at the position of the window specimen, conduct two tests under conditions close to the specimen test conditions, and then solve M1 and M2 by the following two equations: [Q-Mi·01-M2·02=A·G·△0s
[Q'-M· △1-M2·2-AG·
·..·(2)
**·(3)www.bzxz.net
wherein G and A are the thermal conductivity and area of ​​the standard specimen respectively; △91, △92 and △93 are the temperature differences between the outer wall of the hot chamber, the specimen frame and the standard specimen respectively; the symbols in equation (3) are the parameters corresponding to equation (2) in the second test. The two calibration tests shall be conducted under the condition that the air temperature difference on both sides of the specimen is the same or close, and the absolute values ​​of △1 and △1 are not less than 3K, the difference between △1 and △91 is not less than 6K, and △2 and △2 are as close or equal as possible.
5.6.3 Standard specimen
5.6.3.1 The standard specimen shall be made of uniform, airtight material, no air layer inside, and stable thermal performance. The size is 1500mmX1500mm. A 50mm thick semi-rigid polystyrene foam plastic board that has been stored for a long time can be used as the standard specimen. 5.6.3.2 The thermal conductivity G value of the standard specimen shall be measured according to the large flat plate method of one-way heat transfer heat protection plate under temperature difference conditions similar to those of the calibration test.
5.6.4 Calibration interval
5.6.4.1 The calibration test shall be conducted regularly, not less than once a year. 5.6.4.2 When the material, structure or opening size of the test piece frame is changed, it should be recalibrated. 5.7 Measurement
5.7.1 Electric heater heating power
5.7.1.1 The electric heater heating power Q[W is calculated according to the following formula: Q=IV
Where: I is the current passing through the heating wire of the electric heater, A; V is the voltage across the heating wire, V.
5.7.1.2 The current and voltage are measured with an AC ammeter and a voltmeter respectively. The instrument grade should not be lower than grade 0.5, and should be able to be greater than the conversion range according to the measured value, so that it is at more than 70% of the full range. 5.7.2 Temperature
5.7.2.1 The temperature is measured with a copper-constantan thermocouple with a wire diameter less than 0.4mm, and the measurement accuracy should not be lower than ±0.1℃. 5.7.2.2 Air temperature
a. The air temperature measurement points of the hot room should be evenly distributed in the hot room space, and the number of measurement points should not be less than 8 points. The measurement points should be about 500mm away from the wall.
b. The air temperature measurement points of the cold room should be arranged in a plane more than 100mm away from the surface of the specimen. 9 points are evenly arranged on the 1500mm×1500mm area corresponding to the hole. The arrangement position does not need to change with the change of the hole size. c. All air temperature probes should be equipped with shielding covers to avoid the influence of thermal radiation. d. The air temperature measurement points of the hot and cold rooms can be connected in parallel to measure their respective average temperatures. 5.7.2.3 Surface temperature
a. The number of points on each inner and outer surface of each outer wall of the hot room should not be less than 5. b. The number of points on each side of the hot and cold side surfaces of the specimen frame should not be less than 8. In the parts affected by the radiation of the electric heater, representative positions should be selected through tests for point arrangement.
c. The surface temperature measuring points should be arranged correspondingly and can be connected into thermocouples to directly measure the surface temperature difference. d. The surface temperature measuring points should be attached to the measured surface with adhesive materials together with at least 100mm long leads. The blackness e value of the adhesive material should be close to the measured surface.
e. The temperature measuring points on each surface of the hot chamber outer wall and the specimen frame can be connected in parallel to measure their respective average temperatures. When connected in parallel, the resistance of each thermocouple lead must be equal.
5.7.3 Wind speed and pressure difference
5.7.3.1 The wind speed in the cold chamber can be measured by a calibrated thermoelectric anemometer, and the measuring point position is the same as the cold air temperature measuring point. 5.7.3.2 The air pressure difference between the hot and cold chambers is measured by a compensated micromanometer. The measuring head should be placed in the middle of the hole height and not affected by the airflow. 5.7.3.3 Wind speed and pressure difference only need to be checked regularly and do not need to be measured every time. 5.8 Test Procedure
5.8.1 Install and seal the test piece according to the requirements of 5.4. W.bzsoso.cO Engineering Construction Standard Full Text Information System
5.8.2 Start the test device and control the temperature of the hot and cold rooms according to the requirements of 5.5. 5.8.3 When the temperature of the hot and cold rooms reaches the specified requirements and the heating power of the electric heater remains stable for 4 hours, start measuring various parameters. 5.8.4 When the hourly measured temperature of the hot room and the temperature difference between the inner and outer surfaces of the outer wall of the hot room △91 change less than or equal to 0.1K per hour, the temperature of the cold room t. and the temperature difference between the hot and cold surfaces of the test piece frame △92 change less than or equal to 0.3K per hour, and it is not a unidirectional change, it is considered to have entered a stable state.
5.8.5 After entering a stable state, measure t, t. and △01, △02 and Q once an hour. 5.8.6 Take the average of the four measurement results and calculate the heat transfer coefficient K value according to formula (1) or formula (5). 5.9 Test results
5.9.1 The heat transfer coefficient K value of single-layer window and single-frame double-glass specimens is calculated according to formula (1). 5.9.2 The heat transfer coefficient K value of double-layer window specimens is calculated according to the following formula: K=-M·A-(M2+AM)Ae2
（5）
Wherein, △M2 is the correction introduced due to the increase in specimen thickness. In this test device, △M2 is taken as 0.22W/K, and the other symbols are the same as formula (1).
5.9.3 When the specimen area is smaller than the opening size, a polystyrene foam board with the same thickness as the specimen should be used to seal the gap, and the heat loss through the board should be measured. When calculating the heat transfer coefficient K value of single-layer window and double-layer window specimens, this heat loss should be subtracted from the numerator of formula (1) and formula (5) respectively.
5.9.4 The calculation result shall be rounded to three significant figures. 5.10 Test report
The test report shall include the following contents:
a. Specimen number, source or entrusted unit. b. Specimen type and size, structural diagram, glass type and thickness, window frame material, window frame window opening area ratio, air permeability performance level and sealing treatment during installation.
c. Test conditions: hot room temperature, cold room temperature and air flow velocity. d. Test results: K, Q, t, te, △91, △92 and thermal insulation performance level. e. Signatures of the tester and the person in charge.
f. Name and address of the testing unit, stamped with the official seal and dated. Additional notes:
This standard is under the jurisdiction of the China Building Standard Design Institute. This standard was drafted and interpreted by the Institute of Building Physics of the China Academy of Building Research.2 When the material, structure or opening size of the test piece frame changes, it should be recalibrated. 5.7 Measurement
5.7.1 Electric heater heating power
5.7.1.1 The electric heater heating power Q[W is calculated according to the following formula: Q=IV
Where: I is the current passing through the heating wire of the electric heater, A; V is the voltage across the heating wire, V.
5.7.1.2 The current and voltage are measured with an AC ammeter and a voltmeter respectively. The instrument grade should not be lower than grade 0.5, and should be able to be greater than the conversion range according to the measured value, so that it is at more than 70% of the full range. 5.7.2 Temperature
5.7.2.1 The temperature is measured with a copper-constantan thermocouple with a wire diameter less than 0.4mm, and the measurement accuracy should not be lower than ±0.1℃. 5.7.2.2 Air temperature
a. The air temperature measurement points of the hot room should be evenly distributed in the hot room space, and the number of measurement points should not be less than 8 points. The measurement points should be about 500mm away from the wall.
b. The air temperature measurement points of the cold room should be arranged in a plane more than 100mm away from the surface of the specimen. 9 points are evenly arranged on the 1500mm×1500mm area corresponding to the hole. The arrangement position does not need to change with the change of the hole size. c. All air temperature probes should be equipped with shielding covers to avoid the influence of thermal radiation. d. The air temperature measurement points of the hot and cold rooms can be connected in parallel to measure their respective average temperatures. 5.7.2.3 Surface temperature
a. The number of points on each inner and outer surface of each outer wall of the hot room should not be less than 5. b. The number of points on each side of the hot and cold side surfaces of the specimen frame should not be less than 8. In the parts affected by the radiation of the electric heater, representative positions should be selected through tests for point arrangement.
c. The surface temperature measuring points should be arranged correspondingly and can be connected into thermocouples to directly measure the surface temperature difference. d. The surface temperature measuring points should be attached to the measured surface with adhesive materials together with at least 100mm long leads. The blackness e value of the adhesive material should be close to the measured surface.
e. The temperature measuring points on each surface of the hot chamber outer wall and the specimen frame can be connected in parallel to measure their respective average temperatures. When connected in parallel, the resistance of each thermocouple lead must be equal.
5.7.3 Wind speed and pressure difference
5.7.3.1 The wind speed in the cold chamber can be measured by a calibrated thermoelectric anemometer, and the measuring point position is the same as the cold air temperature measuring point. 5.7.3.2 The air pressure difference between the hot and cold chambers is measured by a compensated micromanometer. The measuring head should be placed in the middle of the hole height and not affected by the airflow. 5.7.3.3 Wind speed and pressure difference only need to be checked regularly and do not need to be measured every time. 5.8 Test Procedure
5.8.1 Install and seal the test piece according to the requirements of 5.4. W.bzsoso.cO Engineering Construction Standard Full Text Information System
5.8.2 Start the test device and control the temperature of the hot and cold rooms according to the requirements of 5.5. 5.8.3 When the temperature of the hot and cold rooms reaches the specified requirements and the heating power of the electric heater remains stable for 4 hours, start measuring various parameters. 5.8.4 When the hourly measured temperature of the hot room and the temperature difference between the inner and outer surfaces of the outer wall of the hot room △91 change less than or equal to 0.1K per hour, the temperature of the cold room t. and the temperature difference between the hot and cold surfaces of the test piece frame △92 change less than or equal to 0.3K per hour, and it is not a unidirectional change, it is considered to have entered a stable state.
5.8.5 After entering a stable state, measure t, t. and △01, △02 and Q once an hour. 5.8.6 Take the average of the four measurement results and calculate the heat transfer coefficient K value according to formula (1) or formula (5). 5.9 Test results
5.9.1 The heat transfer coefficient K value of single-layer window and single-frame double-glass specimens is calculated according to formula (1). 5.9.2 The heat transfer coefficient K value of double-layer window specimens is calculated according to the following formula: K=-M·A-(M2+AM)Ae2
（5）
Wherein, △M2 is the correction introduced due to the increase in specimen thickness. In this test device, △M2 is taken as 0.22W/K, and the other symbols are the same as formula (1).
5.9.3 When the specimen area is smaller than the opening size, a polystyrene foam board with the same thickness as the specimen should be used to seal the gap, and the heat loss through the board should be measured. When calculating the heat transfer coefficient K value of single-layer window and double-layer window specimens, this heat loss should be subtracted from the numerator of formula (1) and formula (5) respectively.
5.9.4 The calculation result shall be rounded to three significant figures. 5.10 Test report
The test report shall include the following contents:
a. Specimen number, source or entrusted unit. b. Specimen type and size, structural diagram, glass type and thickness, window frame material, window frame window opening area ratio, air permeability performance level and sealing treatment during installation.
c. Test conditions: hot room temperature, cold room temperature and air flow velocity. d. Test results: K, Q, t, te, △91, △92 and thermal insulation performance level. e. Signatures of the tester and the person in charge.
f. Name and address of the testing unit, stamped with the official seal and dated. Additional notes:
This standard is under the jurisdiction of the China Building Standard Design Institute. This standard was drafted and interpreted by the Institute of Building Physics of the China Academy of Building Research.2 When the material, structure or opening size of the test piece frame changes, it should be recalibrated. 5.7 Measurement
5.7.1 Electric heater heating power
5.7.1.1 The electric heater heating power Q[W is calculated according to the following formula: Q=IV
Where: I is the current passing through the heating wire of the electric heater, A; V is the voltage across the heating wire, V.
5.7.1.2 The current and voltage are measured with an AC ammeter and a voltmeter respectively. The instrument grade should not be lower than grade 0.5, and should be able to be greater than the conversion range according to the measured value, so that it is at more than 70% of the full range. 5.7.2 Temperature
5.7.2.1 The temperature is measured with a copper-constantan thermocouple with a wire diameter less than 0.4mm, and the measurement accuracy should not be lower than ±0.1℃. 5.7.2.2 Air temperature
a. The air temperature measurement points of the hot room should be evenly distributed in the hot room space, and the number of measurement points should not be less than 8 points. The measurement points should be about 500mm away from the wall.
b. The air temperature measurement points of the cold room should be arranged in a plane more than 100mm away from the surface of the specimen. 9 points are evenly arranged on the 1500mm×1500mm area corresponding to the hole. The arrangement position does not need to change with the change of the hole size. c. All air temperature probes should be equipped with shielding covers to avoid the influence of thermal radiation. d. The air temperature measurement points of the hot and cold rooms can be connected in parallel to measure their respective average temperatures. 5.7.2.3 Surface temperature
a. The number of points on each inner and outer surface of each outer wall of the hot room should not be less than 5. b. The number of points on each side of the hot and cold side surfaces of the specimen frame should not be less than 8. In the parts affected by the radiation of the electric heater, representative positions should be selected through tests for point arrangement.
c. The surface temperature measuring points should be arranged correspondingly and can be connected into thermocouples to directly measure the surface temperature difference. d. The surface temperature measuring points should be attached to the measured surface with adhesive materials together with at least 100mm long leads. The blackness e value of the adhesive material should be close to the measured surface.
e. The temperature measuring points on each surface of the hot chamber outer wall and the specimen frame can be connected in parallel to measure their respective average temperatures. When connected in parallel, the resistance of each thermocouple lead must be equal.
5.7.3 Wind speed and pressure difference
5.7.3.1 The wind speed in the cold chamber can be measured by a calibrated thermoelectric anemometer, and the measuring point position is the same as the cold air temperature measuring point. 5.7.3.2 The air pressure difference between the hot and cold chambers is measured by a compensated micromanometer. The measuring head should be placed in the middle of the hole height and not affected by the airflow. 5.7.3.3 Wind speed and pressure difference only need to be checked regularly and do not need to be measured every time. 5.8 Test Procedure
5.8.1 Install and seal the test piece according to the requirements of 5.4. W.bzsoso.cO Engineering Construction Standard Full Text Information System
5.8.2 Start the test device and control the temperature of the hot and cold rooms according to the requirements of 5.5. 5.8.3 When the temperature of the hot and cold rooms reaches the specified requirements and the heating power of the electric heater remains stable for 4 hours, start measuring various parameters. 5.8.4 When the hourly measured temperature of the hot room and the temperature difference between the inner and outer surfaces of the outer wall of the hot room △91 change less than or equal to 0.1K per hour, the temperature of the cold room t. and the temperature difference between the hot and cold surfaces of the test piece frame △92 change less than or equal to 0.3K per hour, and it is not a unidirectional change, it is considered to have entered a stable state.
5.8.5 After entering a stable state, measure t, t. and △01, △02 and Q once an hour. 5.8.6 Take the average of the four measurement results and calculate the heat transfer coefficient K value according to formula (1) or formula (5). 5.9 Test results
5.9.1 The heat transfer coefficient K value of single-layer window and single-frame double-glass specimens is calculated according to formula (1). 5.9.2 The heat transfer coefficient K value of double-layer window specimens is calculated according to the following formula: K=-M·A-(M2+AM)Ae2
（5）
Wherein, △M2 is the correction introduced due to the increase in specimen thickness. In this test device, △M2 is taken as 0.22W/K, and the other symbols are the same as formula (1).
5.9.3 When the specimen area is smaller than the opening size, a polystyrene foam board with the same thickness as the specimen should be used to seal the gap, and the heat loss through the board should be measured. When calculating the heat transfer coefficient K value of single-layer window and double-layer window specimens, this heat loss should be subtracted from the numerator of formula (1) and formula (5) respectively.
5.9.4 The calculation result shall be rounded to three significant figures. 5.10 Test report
The test report shall include the following contents:
a. Specimen number, source or entrusted unit. b. Specimen type and size, structural diagram, glass type and thickness, window frame material, window frame window opening area ratio, air permeability performance level and sealing treatment during installation.
c. Test conditions: hot room temperature, cold room temperature and air flow velocity. d. Test results: K, Q, t, te, △91, △92 and thermal insulation performance level. e. Signatures of the tester and the person in charge.
f. Name and address of the testing unit, stamped with the official seal and dated. Additional notes:
This standard is under the jurisdiction of the China Building Standard Design Institute. This standard was drafted and interpreted by the Institute of Building Physics of the China Academy of Building Research.2 The heat transfer coefficient K value of the double-layer window specimen is calculated as follows: K = -M·A-(M2+AM)Ae2
（5）
Wherein, △M2 is the correction introduced due to the increase in the thickness of the specimen. In this test device, △M2 is taken as 0.22W/K, and the other symbols are the same as those in formula (1).
5.9.3 When the specimen area is smaller than the hole size, a polystyrene foam board with the same thickness as the specimen should be used to block the gap, and the heat loss through the board should be measured. When calculating the heat transfer coefficient K value of the single-layer window and double-layer window specimens, this heat loss should be subtracted from the numerator of formula (1) and formula (5) respectively.
5.9.4 The calculation result shall be rounded to three significant figures. 5.10 Test report
The test report shall include the following contents:
a. Test specimen number, source or entrusting unit. b. Type and size of test piece, structural diagram, glass type and thickness, window frame material, window frame window opening area ratio, air permeability performance level and sealing treatment during installation.
c. Test conditions: hot room temperature, cold room temperature and air flow velocity. d. Test results: K, Q, t, te, △91, △92 and thermal insulation performance level. e. Signature of the tester and person in charge.
f. Name and address of the testing unit, with official seal and date. Additional notes:
This standard is under the jurisdiction of the China Building Standard Design Institute. This standard was drafted and interpreted by the Institute of Building Physics, China Academy of Building Research. W.bzsoso.co2 The heat transfer coefficient K value of the double-layer window specimen is calculated as follows: K = -M·A-(M2+AM)Ae2
（5）
Wherein, △M2 is the correction introduced due to the increase in the thickness of the specimen. In this test device, △M2 is taken as 0.22W/K, and the other symbols are the same as those in formula (1).
5.9.3 When the specimen area is smaller than the hole size, a polystyrene foam board with the same thickness as the specimen should be used to block the gap, and the heat loss through the board should be measured. When calculating the heat transfer coefficient K value of the single-layer window and double-layer window specimens, this heat loss should be subtracted from the numerator of formula (1) and formula (5) respectively.
5.9.4 The calculation result shall be rounded to three significant figures. 5.10 Test report
The test report shall include the following contents:
a. Test specimen number, source or entrusting unit. b. Type and size of test piece, structural diagram, glass type and thickness, window frame material, window frame window opening area ratio, air permeability performance level and sealing treatment during installation.
c. Test conditions: hot room temperature, cold room temperature and air flow velocity. d. Test results: K, Q, t, te, △91, △92 and thermal insulation performance level. e. Signature of the tester and person in charge.
f. Name and address of the testing unit, with official seal and date. Additional notes:
This standard is under the jurisdiction of the China Building Standard Design Institute. This standard was drafted and interpreted by the Institute of Building Physics, China Academy of Building Research. W.bzsoso.co
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