1、ANSVASHRAE 96-1980 ASHRAE 96 BO m 0759650 0503902 441 m D- ci (RA 1989) (Reaffirmation of ANWASHRAE 96-1980) AN AMERICAN NATIONAL STANDARD METHODS OF TESTING TO DETERMINE THE THERMAL PERFORMANCE OF UNGLAZED FLAT-PLATE LIQUID-TYPE SOLAR COLLECTORS Reaffirmed by the ASHRAE Standards Committee Januaty
2、28, 1989, by the ASHRAE Board of Directors, Februaty2,1989 and by the American National Standards Institutes Board of Standards Review, August 24,1989. ASHRAE Standards are updated on afive-year cycle; the date following the Standard number is the year of approval. The latest copies may be purchased
3、 from the ASHRAE Publica- tions Sales Department, 1791 Tullie Circle, NE, Atlanta, GA 30329. 01989 ISSN 1041-2336 AMERICAN SOCIETY OF HEATING, REFRIGERATING AND AIR-CONDITIONING ENGINEERS, INC. 1791 Tullie Circle, NE Atlanta, GA 30329 ASHRAE 96 80 S 0759650 0503703 388 m ASHRAE STANDARD PROJECT COMM
4、ITTEE 96 Robert E. Cook, Chairman Robert L. Berg James C. Burke Robert Dominquez Freeman A. Ford Henry C. Waechter, Liaison Dr. James E. Hill Dr. Metin Lokmanhekim Edward Maybeck Arthur T. Sales G. Yuill ASHRAE STANDARDS COMMITTEE 1988-89 Don Virgin, Chairman George S. Yamamoto, Vice Chairman Harvey
5、 Brickman Donald G. Colliver David R. Conover Ernest C. Dowless George A. Freeman Donald L. Geistert Tamami Kusuda Ralph D. Lahmon Carl N. Lawson R. Michael Martin Paul L. Miller, Jr. Herbert Phillips Julian E. Sjordal Harold E. Straub Kevin Y. Teichman A. Grant Wilson Donald G. Rich, CO Hans O. Spa
6、uschus, Ex0 Victor Goldschmidt, International Liaison Jim L. Heldenbrand, Manager of Standards SPECIAL NOTE This National Voluntary Consensus Standard was developed under the auspices of the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE). Consensus is defined as “
7、substantial agreement reached by concerned interests according to the judgment of a duly appointed authority, after a concerted attempt at resolving objections. Consensus implies much more than the concept of a simple majority but not necessarily unanimity.” This definition is according to the Ameri
8、can National Standards Institute (ANSI) of which ASHRAE is a member. ASHRAE obtains consensus through participation of its national and international members, associated societies and public review. ASHRAE Standards are prepared by a Project Committee appointed specifically for the purpose of writin
9、g the Standard. The Project Committee Chairman and Vice-chairman must be members of ASHRAE; while other memberc may or may not be members, all must be technically qualified in the subject area of the Stan- dard. Every effort is made to balance the concerned interests on all Project Committees. The M
10、anager of Standards of ASHRAE should be contacted for: a. interpretation of the contents of this Standard. b. participation in the next review of the Standard. c. offering constructive criticism for improving the Standard. d. permission to reprint portions of the Standard. ASHRAE INDUSTRIAL ADVERTIS
11、ING POLICY ON STANDARDS ASHRAE Standards are established to assist industry and the public by offering a uniform method of testing for rating purposes, by suggesting safe practices in designing and installing equipment, by providing proper definitions of this equipment and by providing other informa
12、tion which may serve to guide the industry. The creation of ASHRAE Standards is determined by the need for them, and conformance to them is completely voluntary. In referring to this Standard and in marking of equipment and in advertising, no claim shall be made, either stated or implied, that the p
13、roduct has been approved by ASHRAE. I DISCLAIMER ASHRAE uses its best efforts to promulgate standards for the benefit of the public in light of available information and accepted industry practices. However, ASHRAE does not guarantee, certify or assure the safety or performance of any products, comp
14、onents or systems tested, designed, installed or operated in accordance with ASHRAEs standards or that any tests conducted under its standards will be non-hazardous or free from risk. CONTENTS Section Page Foreword 3 Nomenclature 3 1 . Purpose 3 2 . Scope 3 3 . Definitions 3 4 . Classifications . 4
15、5 . Requirements 4 6 . Instrumentation 5 7 . Apparatus and Method of Testing . 6 8 . Test Procedure and Computations 9 9 . Data to be Recorded and Test Report . 14 10 . References . 16 Test ReportTable1 . 14 Test ReportTable2 . 14 AppendixA . 16 Appendix6 . 17 AppendixC . 27 . ASHRAE 96 80 D 0759650
16、 0503904 214 ASHRAE S“DARD 96-1980 (RA 1989) 1 2 ASHRAE 96 80 W 0759650 0503905 150 ASHRAE STANDARD 96-1980 (RA 1989) ASHRAE 96 BO W 0759650 0503906 097 H This Foreword is not part of this Standard but is provided for information purposes only. FOREWORD This Standard describes tests for determining
17、the ther- mal performance of unglazed collectors used in low temperature applications such as heating of swimming pools and with heat pumps. Glazed and/or concentrating collectors used in these same applications are intended to be tested for thermal performance in accordance with ASH= Standard 93-19
18、86. It should be recognized that the thermal performance of a single collector may not be indicative of the performance of a collector array consisting of a number of modules of the same collector. The 1980 Standard was recommended for reaffirma- tion with minor editorial changes by the Standards Co
19、m- mittee on June 28, 1987. Since the ASHRAE Journal intent-to-reaffirm notice elicited no negative comments, the Board of Directors approved the reaffirmation with minor editorial changes on February 2, 1989. 1.0 PURPOSE 1.1 The purpose of this Standard is to provide test methods for determining th
20、e thermal performance of unglazed flat-plate liquid-type solar energy collector modules (hereinafter called solar collectors) which heat a liquid for low temperature applications. 2.0 SCOPE 2.1 Application. This Standard applies to unglazed flat- plate liquid-type solar collectors to be used in low
21、temperature applications and in which a liquid enters the collector through a single inlet and leaves the collector through a single outlet. 2.1.1 Collectors containing more than one inlet and more than one outlet may be tested according to this Stan- dard provided that the external piping can be co
22、nnected so as to provide effectively a single inlet and a single outlet. 2.1.2 Collectors, other than unglazed flat-plate liquid- type, which are intended for low temperature applications should be tested in accordance with ASHRAE Standard 93-1986 modified in accordance with the requirements of Sect
23、ion 8.3 of this Standard. 2.2 Outdoor and Indoor Testing. This Standard contains methods for conducting tests outdoors under natural solar irradiation and for conducting tests indoors under simu- lated solar irradiation. 2.3 Test Methods and Calculation Procedures. This Stan- dard provides test meth
24、ods and calculations procedures for determining steady-state and quasi-steady-state thermal performance, and angular response characteristics of the solar collectors. NOMENCLATURE a,b A, = constants used in incident angle modifier equation, = transparent frontal area or aperture area for a flat- dim
25、ensionless ASHM S“DARD 961980 (RA 1989) plate collector, m2 (ft2) = gross collector area, m2 (ftz) = constant used in incident angle modifier equation, CP = specific heat of the transfer fluid, J/(kg. OC) F, = solar collector heat removal factor, dimensionless I, = direct normal solar irradiation, i
26、Wm2 Btu/(h * ftz) Id = diffuse solar irradiation incident upon the aperture Is, = solar constant, 1353 W/m2 429.2 Btu/(h.ftz) 4 = total solar irradiation incident upon the aperture plane of collector, W/m2 Btu/(h ft2) Ka, = incident angle modifier, dimensionless LST = local standard time, decimal ho
27、urs LSTM = local standard time meridian, deg A, bo dimensionless Btu/ (lb * OF) plane of collector, V/mZ Btu/(h ftz) = apparent solar time, decimal hours = mass flow rate of the transfer fluid, kg/s (lb/h) = theoretical power required to move the transfer = pressure drop across the collector, Pa (lb
28、/in.) = rate of useful energy extraction from the collector, = ambient air temperature, “C (OF) = temperature of the transfer fluid leaving the collector, “C (OF) = temperature of the transfer fluid entering the collector, “C (OF) = average temperature of the absorber surface for a flat-plate collec
29、tor, “C (OF) = temperature difference, “C (OF) = solar collector heat transfer loss coefficient, W/(m2-“C) Btu/(h*ft2-“F) = density, kg/m3 (lb/ft3) = absorptance of the collector absorber surface for solar radiation, dimensionless = angle of incidence between direct solar rays and the normal to the
30、collector surface or to the aperture, deg = collector efficiency based on gross collector area, 070 = wavelength, pm = transmittance of the solar collector cover plate, dimen- sionless (if no cover plate is used, r = 1.0) = effective transmittance-absorptance product, dimensionless = effective trans
31、mittance-absorptance product at nor- mal incidence, dimensionless = time at the beginning and end of a test period, fluid through the collector, W (hp) W(Btu/h) decimal hours 3.0 DEFINITIONS absorber: that part of the solar collector which receives the incident radiant energy and transforms it into
32、thermal energy. It may possess a surface through which energy is transmitted to the transfer liquid; however, the transfer liquid itself can be the absorber. absorber area: the total heat transfer area through which the absorbed solar irradiation heats the transfer liquid or of the absorber media if
33、 both transfer liquid and solid surfaces jointly perform the absorbing function. air mass: the ratio of the mass of atmosphere in the actual earth-sun path to the mass which would exist if the sun were directly overhead at sea level. angle of incidence: the angle between the direct solar beam and th
34、e normal to the aperture plane. aperture area: the maximum projected area of a solar col- lector through which the unconcentrated solar radiant energy is admitted. 3 ASHRAE 96 80 area, gross collector: the maximum projected area of the complete collector module exclusive of integral mounting means a
35、nd liquid connectors. For assemblies of collectors, gross area includes the entire area of the assembly. collector, unglazed: a solar collector in which the absorb- ing surface is directly exposed to the atmosphere. collector, gat-plate: a non-concentrating solar collector in which the absorbing sur
36、face is essentialy planar. collimation angle: the angle within which the radiation beams from the source depart from the line drawn from the source to the receiver. insolation: see Irradiation, Instantaneous. irradiation, instantaneous: the total quantity of solar radia- tion incident on a unit surf
37、ace area in unit time, measured in W/m2 (Btu/(h.ft2). instantaneous efficiency: the amount of energy removed by the transfer liquid per unit of gross collector area during the specified time period divided by the total solar radiation incident on the collector per unit area during the same time peri
38、od, under steady-state or quasi-steady-state conditions. Pyranometer: a radiometer used to measure the total solar radiation incident upon a surface per unit time per unit area. This energy includes the direct radiation, the diffuse sky radiation, and the solar radiation reflected from the foregroun
39、d. pyrheliometer: a radiometer used to measure the direct radiation on a surface normal to the suns rays. quasi-steady-state: describes the state of the solar coilector test when the flow rate and temperature of the liquid enter- ing the collector are constant but the exit fluid temperature changes
40、gradually due to the normal change in irradiation that occurs with time for clear sky conditions. solar collector: a device designed to absorb incident solar radiation and to transfer the energy to a liquid passing through it. temperature, ambient air: the temperature of the air sur- rounding the so
41、lar collector being tested. transfer liquid, heat: the medium which passes through the solar collector and carries the absorbed thermal energy away from the collector. 4.0 CLASSIFICATIONS 4.1 Basis of Classifications. Solar collectors may be classified according to their collecting characteristics,
42、the way in which they are mounted, the type of transfer liquid, and the flow direction which they employ. Collecting Characteristics. An unglazed flat-plate collector is one in which the absorbing surface is directly exposed to the atmosphere, where the absorbing surface is essentially flat, and in
43、which the aperture and the absorber are similar in area and geometry. Other types include glazed (single or multiple) and/or concentrating collectors. 4.1.2 Mounting. A solar collector may be mounted in a stationary position with a fixed azimuth and tilt angle (measured from the horizontal) or it ma
44、y be adjustable as to tilt angle to follow the annual changes in solar declination. 4.1.1 0759650 0503907 T23 4.1.3 Type of Liquid. In low temperature appiications, collectors normally employ water circulated directly through the passages in the collector. They may however, employ a heat transfer li
45、quid and a heat exchanger to heat the water. 4.1.4 Flow Direction. The liquid may flow in any man- ner through the collector. Figures 1,2 and 3 show flow from bottom to top. 5.0 REQUIREMENTS 5.1 General. Unglazed flat-plate liquid-type solar collec- tors shall be tested in accordance with the provis
46、ions set forth in this Section and in Section 8. 5.1.1 Preconditioning. The collector whose thermal performance is to be tested in accordance with this docu- ment shall be preconditioned prior to initiation of the test. Preconditioning shall consist of stagnation heating in a non-operational mode in
47、 a dry condition for not less than three days (not necessarily successive) in which the cumulative mean incident solar radiation measured in the plane of the collector shall be not less than 17,000 kJ/(m2 day) (1500 Btu/(ftz day). The exposure angle shall be the angle of test specified herein. 5.1.2
48、 Size of Test Sample. Testing of full scale modules is preferred. The size of the collector to be tested shall be large enough so that the performance characteristics deter- mined will be indicative of those that would occur when the collector is part of an installed system. If the collector is modu
49、lar and the test is being done on one module, it should be mounted and insulated in such a way that the back and edge losses will be characteristic of those that will occur during operation on a structure. If special liquid connec- tors are furnished or required by the manufacturer of the collector, they shall be used for introducing the fluid dur- ing testing. If the manufacturer recommends or furnishes a special panel inter-connection means, a stub-off unit shail be installed on the panel during testing. Collector Mounting. If the collector module is designed with no bac
