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Standard Practice for Nonoperational Exposure and Inspection of a Solar Collector (Withdrawn 2010)

Standard Practice for Nonoperational Exposure and Inspection of a Solar Collector (Withdrawn 2010)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WITHDRAWN RATIONALE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the direct responsibility of Subcommittee E44.05 on Solar Heating and Cooling Subsystems and Systems, this practice was withdrawn in January 2010 in accordance with section 10.5.3.1 of the Regulations Governing ASTM Technical Committees, which requires that standards shall be updated by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Withdrawn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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Standards Content (Sample)

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
1
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
1
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.
2
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
3
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
2
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.
1

---------------------- Page: 1 ----------------------
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 h
...

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ASTM E781-86(2023)(Practice)
Standard Practice for Evaluating Absorptive Solar Receiver Materials When Exposed to Conditions Simulating Stagnation in Solar Collectors with Cover Plates

SIGNIFICANCE AND USE
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.
Note 1: Mathematical modeling has shown that a selective absorber, single glazed flat-plate solar collector can attain absorber plate stagnation temperatures as high as 226 °C (437 °F) with an ambient temperature of 37.8 °C (100 °F) and zero wind velocity, and a double glazed one as high as 245 °C (482 °F) under these conditions. The same configuration solar collector with a nonselective absorber can attain absorber stagnation temperatures as high as 146 °C (284 °F) if single glazed, and 185 °C (360 °F) if double glazed, with the same environmental conditions (see “Performance Criteria for Solar Heating and Cooling Systems in Commercial Buildings,” NBS Technical Note 1187).4  
4.4 This practice evaluates the thermal stability of absorber materials. It does not evaluate the moisture stability of absorber materials used in actual solar collectors exposed outdoors. Moisture intrusion into solar collectors is a frequent occurrence in addition to condensation caused by diurnal breathing.  
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).  
1.2 This practice shall not apply to receiver materials used in solar collectors without covers (unglazed) or in evacuated collectors, that is, those that use a vacuum to suppress convective and conductive thermal losses.  
1.3 The values stated in SI units are to be regarded as the standard.  
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.  
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ASTM E822-92(2023)(Practice)
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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.  
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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 ...
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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:  
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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.  
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ASTM
ASTM E744-07(2022)(Practice)
Standard Practice for Evaluating Solar Absorptive Materials for Thermal Applications

SIGNIFICANCE AND USE
4.1 The methods in this practice are intended to aid in the assessment of long-term performance by comparative testing of absorptive materials. The results of the methods, however, have not been shown to correlate to actual in-service performance.  
4.2 The testing methodology in this practice provides two testing methods, in accordance with Fig. 1.
FIG. 1 Outline of Test Method Options  
4.2.1 Method A, which aims at decreasing the time required for evaluation, uses a series of individual tests to simulate various exposure conditions.  
4.2.2 Method B utilizes a single test of actual outdoor exposure under conditions simulating thermal stagnation.  
4.2.3 Equivalency of the two methods has not yet been established.
SCOPE
1.1 This practice covers a testing methodology for evaluating absorptive materials used in flat plate or concentrating collectors, with concentrating ratios not to exceed five, for solar thermal applications. This practice is not intended to be used for the evaluation of absorptive surfaces that are (1) used in direct contact with, or suspended in, a heat-transfer liquid, (that is, trickle collectors, direct absorption fluids, etc.); (2) used in evacuated collectors; or (3) used in collectors without cover plate(s).  
1.2 Test methods included in this practice are property measurement tests and aging tests. Property measurement tests provide for the determination of various properties of absorptive materials, for example, absorptance, emittance, and appearance. Aging tests provide for exposure of absorptive materials to environments that may induce changes in the properties of test specimens. Measuring properties before and after an aging test provides a means of determining the effect of the exposure.  
1.3 The assumption is made that solar radiation, elevated temperature, temperature cycles, and moisture are the primary factors that cause degradation of absorptive materials. Aging tests are described for exposure of specimens to these factors.  
Note 1: For some geographic locations, other factors, such as salt spray and dust erosion, may be important. They are not evaluated by this practice.  
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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ASTM
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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