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ASTM E823-81(2001)

(Practice)

Standard Practice for Nonoperational Exposure and Inspection of a Solar Collector (Withdrawn 2010)

Standard Practice for Nonoperational Exposure and Inspection of a Solar Collector (Withdrawn 2010)

SIGNIFICANCE AND USE
Exposure in a nonoperational mode provides for conditioning and assessment of the physical appearance of a solar collector resulting from moderately severe solar irradiation, ambient temperature, and effects of moisture on the various materials or construction.
This practice describes actual exposure conditions that have a high probability of occurring sometime during the installation of a solar collector, or during operation, or malfunction of a solar energy system.
This practice shall be considered to be a limited aging test in that it does not address those aging effects resulting from fluid-to-collector interfaces.
This practice applies to all solar thermal collector types.
SCOPE
1.1 This practice defines the procedure to expose a solar thermal collector to an outdoor or simulated outdoor environment in a nonoperational model. The procedure provides for periodic inspections and a post-exposure disassembly and inspection of the collector.
1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
WITHDRAWN RATIONALE
This practice defines the procedure to expose a solar thermal collector to an outdoor or simulated outdoor environment in a nonoperational model. The procedure provides for periodic inspections and a post-exposure disassembly and inspection of the collector.
Formerly under the jurisdiction of Committee E44 on Solar, Geothermal and Alternative Engergy Sources and the direct responsibility of Subcommittee E44.05 on Solar Heating and Cooling Subsystems and Systems, this practice was withdrawn in January 2010 in accordance with section 10.5.3.1 of the Regulations Governing ASTM Technical Committees, which requires that standards shall be updated by the end of the eighth year since the last approval date.

General Information

Status
Withdrawn
Publication Date
28-May-1981
Withdrawal Date
31-Jan-2010
ICS
27.160 - Solar energy engineering
Technical Committee
E44 - Solar, Geothermal and Other Alternative Energy Sources
Current Stage
Ref Project

Relations

Replaces
ASTM E823-81(1995)e1 - Standard Practice for Nonoperational Exposure and Inspection of a Solar Collector
Effective Date
29-May-1981
Referred By
ASTM E1160-13(2021) - Standard Guide for On-Site Inspection and Verification of Operation of Solar Domestic Hot Water Systems
Effective Date
29-May-1981

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ASTM E823-81(2001) - Standard Practice for Nonoperational Exposure and Inspection of a Solar Collector (Withdrawn 2010)ASTM E823-81(2001) - Standard Practice for Nonoperational Exposure and Inspection of a Solar Collector (Withdrawn 2010)
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ASTM E823-81(2001) - Standard Practice for Nonoperational Exposure and Inspection of a Solar Collector (Withdrawn 2010)
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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information.
Designation:E823–81 (Reapproved 2001)
Standard Practice for
Nonoperational Exposure and Inspection of a Solar
Collector
This standard is issued under the fixed designation E823; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope installation of a solar collector, or during operation, or mal-
function of a solar energy system.
1.1 This practice defines the procedure to expose a solar
3.3 This practice shall be considered to be a limited aging
thermal collector to an outdoor or simulated outdoor environ-
testinthatitdoesnotaddressthoseagingeffectsresultingfrom
ment in a nonoperational model. The procedure provides for
fluid-to-collector interfaces.
periodic inspections and a post-exposure disassembly and
3.4 This practice applies to all solar thermal collector types.
inspection of the collector.
1.2 This standard does not purport to address all of the
4. Test Specimen
safety concerns, if any, associated with its use. It is the
4.1 The exposure specimen shall consist of a complete
responsibility of the user of this standard to establish appro-
collector. The collector specimens may be equipped with
priate safety and health practices and determine the applica-
self-contained, self-actuated protective devices.
bility of regulatory limitations prior to use.
5. Collector Mounting
2. Referenced Documents
2 5.1 Theexposurespecimenshallconsistofacompleteairor
2.1 ASTM Standards:
liquid solar collector undergoing the nonoperational mode
E772 Terminology Relating to Solar Energy Conversion
exposure. Cap (not seal) all inlet, outlet, and vent ports not
E892 Tables for Terrestrial Solar Spectral Irradiance at Air
normally exposed to rain.
Mass 1.5 for a 37° Tilted Surface
5.2 Locate the exposure rack such that it is clear of
2.2 ASHRAE Standard:
obstruction that may cause shadows or nonuniform reflections
93-77 Methods of Testing to Determine the Thermal Perfor-
3 on the collector.
mance of Solar Collectors
5.3 During exposure, mount the collector to the exposure
3. Significance and Use rack in accordance with the manufacturer’s instructions. When
specific exposure mounting instructions are not provided,
3.1 Exposure in a nonoperational mode provides for condi-
mount the collector to permit air movement on all sides and
tioning and assessment of the physical appearance of a solar
edges. Cover the collector for protection from the weather
collector resulting from moderately severe solar irradiation,
elements until the exposure period commences.
ambient temperature, and effects of moisture on the various
materials or construction.
6. Nonoperational Mode Exposure
3.2 This practice describes actual exposure conditions that
6.1 Mount the collector securely to an adjustable rack,
have a high probability of occurring sometime during the
prepare for nonoperational mode, and expose at the following
conditions:
6.1.1 Aminimum of 30 days during which, for each day, the
This practice is under the jurisdiction of ASTM Committee E44 on Solar,
cumulative minimum radiant exposure, measured in the plane
Geothermal,andOtherAlternativeEnergySourcesandisthedirectresponsibilityof
2 2
Subcommittee E44.05 on Solar Heating and Cooling Subsystems and Systems. of the collector, shall be 17 000 kJ/m ·day (1500 Btu/ft ·day).
Current edition approved May 29, 1981. Published July 1981. DOI: 10.1520/
Minimum conditions do not need to be met for 30 consecutive
E0823-81R01.
days.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
6.1.2 Simulated Solar Radiation:
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on
6.1.2.1 For solar simulation, one solar exposure day is
the ASTM website.
defined as the exposure for5htoa minimum solar irradiance
Available from American Society of Heating, Refrigerating, and Air-
2 2 2
of950W/m (300Btu/ft ·h)andnottoexceed1150W/m (365
Conditioning Engineers, Inc. (ASHRAE), Publications Sales Dept., 1791 Tullie
Circle, N.E., Atlanta, GA 30329. Btu/ft ·h) at an ambient temperature characteristic of outdoor
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
E823–81 (2001)
exposure (nominal range from 15 to 35°C (70 to 95°F)). 6.2 Thermal Shock/Water Spray Penetration—This test is
Simulator exposure is to be followed by setting the collector intended to induce the thermal stresses that will occur when
outdoors overnight in accordance with 5.2.
rain impinges on a heated collector in order to determine the
6.1.2.2 The simulated solar spectrum shall generally con- penetration of rain into the collector and the effect of such
form to the Air Mass 1.5 global distribution as described in
penetration or moisture condensation, if any, on collector
Standard E892.
performance.
6.1.3 The energy distribution in the 0.3 to 0.4-µm range
6.2.1 PeriodofTest—Performthetestthreetimesduringthe
shall not deviate more than 625 % from the Air Mass 1.5
nonoperational mode exposure period; once during the first 10
spectrum as measured in 0.05-µm bands. The energy distribu-
days of the exposure period as defined in 6.1.1, and once each
tion from 0.4 to 2.5 µm shall not deviate by more than 615 %
during the second and third 10 days of the exposure period.
from theAir Mass 1.5 spectrum as measured in 0.10-µm bands.
6.2.2 Pre-Test Exposure—Conduct the spray test after at
6.1.4 A minimum continuous period of 1 h exposure at a
least1hof radiant exposure with a minimum solar irradi-
2 2
solar irradiance greater than 950 W/m (300 Btu/h·ft ). This
2 2
ance of 850 W/m (270 Btu/ft ·h) measured in the plane of the
condition must be experienced in the exposure day in order to
collector.
qualifytheexposuretimeaspartofthe30-hrequirement.Once
6.2.3 Apparatus—The test apparatus shall consist of three
the minimum 1-h exposure period is met, all exposure time
or more spray heads mounted in a water supply rack as shown
(including the 1-h period) above the minimum solar irradiance
in Fig. 1 and Fig. 2. Spray heads shall be constructed in
and ambient temperature requirement during the same expo-
accordance with Fig. 1 and Fig. 2. The water pressure for all
sure day may be included in the 30-h requirement of 6.1.4.
tests shall be maintained at 35 kPa (5 psi) at each spray head.
6.1.5 A minimum of 30 h accumulated radiant exposure
2 2
Thispressurewillprovideabout0.3m/h(12in./h)ofrainatthe
with a solar irradiance not less than 950 W/m (300 Btu/h·ft )
water flow of 190 L/h (50 gal/h) per nozzle. The supply water
concurrent with an ambient temperature of at least 25°C
temperature shall not exceed 30°C (86°F).
(80°F). Measure the solar irradiance in the plane of the
6.2.4 Procedure—Position the spray apparatus to direct a
collector aperture with a pyranometer. The average air velocity
downward spray from a distance of 1.0 m (3 ft) at an angle of
at the test station, measured at a height corresponding to the
45 6 5° with the collector cover plate surface, as illustrated in
mid-height of the collector, should be less than 4.5 m/s (10
Fig. 3. Direct the spray onto the cover plate surface and the top
mph). Record air velocity as part of the test data.
6.1.6 The nonoperational mode exposure is only concluded and side edges of the collector which have been exposed as
described in 6.2. Adjust the water pressure at each spray head
after the requirements of 6.1.1 and 6.1.4 have been met.
Exposure times under 6.1.1 and 6.1.4 shall be accumulated to 35 kPa (5 psi). Maintain the water spray for 15 min per test
period. Observe and record occurrence of water penetratio
...

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4.1 Although this practice is intended for evaluating solar absorber materials and coatings used in flat-plate collectors, no single procedure can duplicate the wide range of temperatures and environmental conditions to which these materials may be exposed during in-service conditions.  
4.2 This practice is intended as a screening test for absorber materials and coatings. All conditions are chosen to be representative of those encountered in solar collectors with single cover plates and with no added means of limiting the temperature during stagnation conditions.  
4.3 This practice uses exposure in a simulated collector with a single cover plate. Although collectors with additional cover plates will produce higher temperatures at stagnation, this procedure is considered to provide adequate thermal testing for most applications.
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4.5 This practice differentiates between the testing of spectrally selective absorbers and nonselective absorbers.  
4.5.1 Testing Spectrally Selective...
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1.1 This practice covers a test procedure for evaluating absorptive solar receiver materials and coatings when exposed to sunlight under cover plate(s) for long durations. This practice is intended to evaluate the exposure resistance of absorber materials and coatings used in flat-plate collectors where maximum non-operational stagnation temperatures will be approximately 200 °C (392 °F).  
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ASTM E822-92(2023)(Practice)
Standard Practice for Determining Resistance of Solar Collector Covers to Hail by Impact with Propelled Ice Balls

SIGNIFICANCE AND USE
2.1 In many geographic areas there is concern about the effect of falling hail upon solar collector covers. This practice may be used to determine the ability of flat-plate solar collector covers to withstand the impact forces of hailstones. In this practice, the ability of a solar collector cover plate to withstand hail impact is related to its tested ability to withstand impact from ice balls. The effects of the impact on the material are highly variable and dependent upon the material.  
2.2 This practice describes a standard procedure for mounting the test specimen, conducting the impact test, and reporting the effects.  
2.2.1 The procedures for mounting cover plate materials and collectors are provided to ensure that they are tested in a configuration that relates to their use in a solar collector.  
2.2.2 The corner locations of the four impacts are chosen to represent vulnerable sites on the cover plate. Impacts near corner supports are more critical than impacts elsewhere. Only a single impact is specified at each of the impact locations. For test control purposes, multiple impacts in a single location are not permitted because a subcritical impact may still cause damage that would alter the response to subsequent impacts.  
2.2.3 Resultant velocity is used to simulate the velocity that may be reached by hail accompanied by wind. The resultant velocity used in this practice is determined by vector addition of a 20 m/s (45 mph) horizontal velocity to the vertical terminal velocity.  
2.2.4 Ice balls are used in this practice to simulate hailstones because natural hailstones are not readily available to use, and ice balls closely approximate hailstones. However, no direct relationship has been established between the effect of impact of ice balls and hailstones. Hailstones are highly variable in properties such as shape, density, and frangibility.2 These properties affect factors such as the kinetic energy delivered to the cover plate, the period during ...
SCOPE
1.1 This practice covers a procedure for determining the ability of cover plates for flat-plate solar collectors to withstand impact forces of falling hail. Propelled ice balls are used to simulate falling hailstones. This practice is not intended to apply to photovoltaic cells or arrays.  
1.2 This practice defines two types of test specimens, describes methods for mounting specimens, specifies impact locations on each test specimen, provides an equation for determining the velocity of any size ice ball, provides a method for impacting the test specimens with ice balls, and specifies parameters that must be recorded and reported.  
1.3 This practice does not establish pass or fail levels. The determination of acceptable or unacceptable levels of ice-ball impact resistance is beyond the scope of this practice.  
1.4 The size of ice ball to be used in conducting this test is not specified in this practice. This practice can be used with various sizes of ice balls.  
1.5 The categories of solar collector cover plate materials to which this practice may be applied cover the range of:  
1.5.1 Brittle sheet, such as glass,  
1.5.2 Semirigid sheet, such as plastic, and  
1.5.3 Flexible membrane, such as plastic film.  
1.6 Solar collector cover materials should be tested as:  
1.6.1 Part of an assembled collector (Type 1 specimen), or  
1.6.2 Mounted on a separate test frame cover plate holder (Type 2 specimen).  
1.7 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.  
1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.9 This international standard was developed in accordance with internatio...

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ASTM E881-92(2022)(Practice)
Standard Practice for Exposure of Solar Collector Cover Materials to Natural Weathering Under Conditions Simulating Stagnation Mode

SIGNIFICANCE AND USE
4.1 This practice describes a weathering box test fixture and establishes limits for the heat loss coefficients. Uniform exposure guidelines are provided to minimize the variables encountered during outdoor exposure testing.  
4.2 Since the combination of elevated temperature and solar radiation may cause some solar collector cover materials to degrade more rapidly than either exposure alone, a weathering box that elevates the temperature of the cover materials is used.  
4.3 This practice may be used to assist in the evaluation of solar collector cover materials in the stagnation mode. No single temperature or procedure can duplicate the range of temperatures and environmental conditions to which cover materials may be exposed during stagnation conditions. To assist in evaluation of solar collector cover materials in the operational mode, Practice E782 should be used. Insufficient data exist to obtain exact correlation between the behavior of materials exposed in accordance with this practice and actual in-service performance.  
4.4 This practice may also be useful in comparing the performance of different materials at one site or the performance of the same material at different sites, or both.  
4.5 Means of evaluating the effects of weathering are provided in Practice E765, and in other ASTM test methods that evaluate material properties.  
4.6 Exposures of the type described in this practice may be used to evaluate the stability of solar collector cover materials when exposed outdoors to the varied influences that comprise weather. Exposure conditions are complex and changeable. Important factors are material temperature, climate, time of year, presence of industrial pollution, etc. Generally, because it is difficult to define or measure precisely the factors influencing degradation due to weathering, results of outdoor exposure tests must be taken as indicative only. Repeated exposure testing at different seasons over a period of more than one year is req...
SCOPE
1.1 This practice covers a procedure for the exposure of solar collector cover materials to the natural weather environment at elevated temperatures that approximate stagnation conditions in solar collectors having a combined back and edge loss coefficient of less than 1.5 W/(m2·°C).  
1.2 This practice is suitable for exposure of both glass and plastic solar collector cover materials. Provisions are made for exposure of single and double cover assemblies to accommodate the need for exposure of both inner and outer solar collector cover materials.  
1.3 This practice does not apply to cover materials for evacuated collectors, photovoltaic cells, flat-plate collectors having a combined back and edge loss coefficient greater than 1.5 W/(m2·°C), or flat-plate collectors whose design incorporates means for limiting temperatures during stagnation.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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ASTM E782-95(2022)(Practice)
Standard Practice for Exposure of Cover Materials for Solar Collectors to Natural Weathering Under Conditions Simulating Operational Mode

SIGNIFICANCE AND USE
3.1 This practice describes a weathering box test fixture and provides uniform exposure guidelines to minimize the variables encountered during outdoor exposure testing.  
3.2 This practice may be useful in comparing the performance of different materials at one site or the performance of the same material at different sites, or both.  
3.3 Since the combination of elevated temperature and solar radiation may cause some solar collector cover materials to degrade more rapidly than either alone, a weathering box that elevates the temperature of the cover materials is used.  
3.4 This practice is intended to assist in the evaluation of solar collector cover materials in the operational, not stagnation mode. Insufficient data exist to obtain exact correlation between the behavior of materials exposed according to this practice and actual in-service performance.  
3.5 Means of evaluation of effects of weathering are provided in Practice E781, and in other ASTM test methods that evaluate material properties.  
3.6 Tests of the type described in this practice may be used to evaluate the stability of solar collector cover materials when exposed outdoors to the varied influences which comprise weather. Exposure conditions are complex and changeable. Important factors are solar radiation, temperature, moisture, time of year, presence of pollutants, etc. These factors vary from site to site and should be considered in selecting locations for exposure. Control samples must always be used in weathering tests for comparative analysis. Outdoor exposure for at least two years is required to make evident changes, such as surface degradation without the use of sophisticated analytical equipment.  
3.7 Temperature conditions attained with this box may not exactly duplicate those that occur under operational conditions with fluid flow. Dependent on environmental exposure conditions, the cover plate temperatures obtained with this box may be higher or lower than those obtained und...
SCOPE
1.1 This practice provides a procedure for the exposure of cover materials for flat-plate solar collectors to the natural weather environment at temperatures that are elevated to approximate operating conditions.  
1.2 This practice is suitable for exposure of both glass and plastic solar collector cover materials. Provisions are made for exposure of single and double cover assemblies to accommodate the need for exposure of both inner and outer solar collector cover materials.  
1.3 This practice does not apply to cover materials for evacuated collectors or photovoltaics.  
1.4 The values stated in SI units are to be regarded as the standard.  
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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