Use of Integrated Day-Long Stagnation Temperature for Measuring Changes in Solar Collector Materials Properties

1985 ◽  
Vol 107 (2) ◽  
pp. 170-175
Author(s):  
W. C. Thomas ◽  
A. G. Dawson ◽  
D. Waksman
Keyword(s):  
Analytical Model ◽  
Test Procedure ◽  
Daily Basis ◽  
Test Methods ◽  
Test Method ◽  
Solar Irradiation ◽  
Stagnation Temperature ◽  
Nonsteady State ◽  
Materials Used ◽  
Energy Absorbing

Measurements of the maximum temperatures reached by solar-energy-absorbing surfaces provide a useful method for detecting possible degradation in the optical and heat transfer properties of materials used in collectors. This investigation shows that a method based on integrating the absorber temperature rise over ambient and solar irradiation on a daily basis has advantages over alternative test methods based on steady-state measurements of either absorber stagnation temperature or collector thermal efficiency. A nonsteady-state analytical model is developed and used to evaluate the sensitivity of the proposed test method to material degradation and environmental effects. Outdoor data are presented to validate the analytical model and depict typical results that can be expected using the test procedure.

Solar Collector Durability Evaluation by Stagnation Temperature Measurements

1983 ◽  
Vol 105 (3) ◽  
pp. 259-267 ◽  
Author(s):  
A. G. Dawson ◽  
W. C. Thomas ◽  
D. Waksman
Keyword(s):  
Prolonged Exposure ◽  
Test Method ◽  
Experimental Results ◽  
Analytical Models ◽  
Energy Output ◽  
Stagnation Temperature ◽  
Solar Absorptance ◽  
Before And After ◽  
Materials Used ◽  
Degradation Of Materials

An analytical and experimental investigation was undertaken to evaluate an alternative method for measuring the thermal degradation of materials used in flat-plate collectors. This test method is based on measuring the temperature of the absorber under a no-flow condition before and after prolonged exposure. The primary material properties of interest are cover transmittance, solar absorptance and infrared emittance of the absorber, and thermal conductivity of insulation. The advantages and limitations of the proposed test method are compared with those for the currently used method, which is based on measuring the energy output from collectors. Experimental results from both outdoor and indoor tests are presented. Steady-state and transient analytical models are developed to evaluate the proposed test method and interpret experimental results. While the measurements required in the proposed method are simpler than those used to measure energy output, other factors, such as nonisothermal absorbers, variations in environmental conditions, and transient response, must be reconciled.

scholarly journals What are the Alternatives of PG Plus Tests for Modified Asphalt Binders?

2019 ◽  
Vol 271 ◽  
pp. 03008
Author(s):  
MM Tariq Morshed ◽  
Mohammad Nazmul Hassan ◽  
Zahid Hossain
Keyword(s):  
Elastic Recovery ◽  
Test Procedure ◽  
Test Methods ◽  
Test Method ◽  
Asphalt Binders ◽  
Performance Grade ◽  
Empirical Performance ◽  
Alternative Test ◽  
Styrene Butadiene ◽  
Departments Of Transportation

For characterizing the polymer modified binders, different state Departments of Transportation (DOTs) use different time consuming and empirical Performance Grade (PG) Plus test methods. Furthermore, the PG Plus tests are silent when asphalt binders are modified with chemicals such as polyphosphoric acid (PPA). But, the effects of the polymer are not accurately identified through these conventional tests such as Elastic Recovery (ER) and tenacity. The main goal of this study is to recommend alternative test method(s), which can possibly be pursued by using, a Dynamic Shear Rheometer (DSR). Thus, Multiple Stress Creep and Recovery (MSCR), ER-DSR, Frequency Sweep, and Binder Yield Energy Test (BYET) are being explored to find their effectiveness. Three PG binders (PG 64-22, PG 70-22 and PG 76-22) have been selected for this investigation. These binders have been prepared with styrene-butadiene-styrene (SBS) polymer, PPA, or a combination of both. Further, chemical tests such as SARA (Saturate, Aromatic, Resin, and Asphaltene) analysis and FTIR (Fourier-transform Infrared spectroscopy) are also being explored to fulfill the objectives. Preliminary findings suggest that the PG Plus tests deem to be obsolete. Also, a single test procedure is not sufficient to identify the presence and effectiveness of modifiers in the PG binders.

The modern methods of pin-type bearing test of metallic materials

2019 ◽  
Vol 85 (7) ◽  
pp. 41-49
Author(s):  
Yaroslava V. Sulimina ◽  
Nikolay O. Yakovlev ◽  
Vladimir S. Erasov ◽  
Aleksey Yu. Ampilogov ◽  
Andrey N. Polyakov ◽  
...  
Keyword(s):  
Elastic Modulus ◽  
Test Procedure ◽  
Test Methods ◽  
Test Method ◽  
Strength Characteristics ◽  
Metallic Materials ◽  
Bearing Strength ◽  
Bearing Stress ◽  
The Impact

The special features of various bearing deformation measurements for pin-type bearing tests of metallic materials are considered along with their impact on the magnitude of the «bearing elastic modulus» and bearing stress. These bearing test methods are present in ASTM and various institutional standards, though no state standard (GOST, GOST R) is currently available for bearing test method of metallic materials. Analysis of additional deformations which arise in determining the degree of hole bearing deformation is carried out. A set of sources of additional deformations is shown to be characteristic for each test procedure and is attributed to the design features of the device, the site and a way of mounting the extensometer. Additional deformations can be both tensile and compressive. It is shown that the impact of additional deformations on the «bearing elastic modulus» is limited to 14% for different procedures. No difference between the methods is revealed with regard to determination of the strength characteristics. At the same time the dispersion decreases with increase in plastic deformation and for bearing deformation about 4% the variation coefficient for all methods is no more than 1%. Advantages and shortcomings of the bearing test methods which affect the reproducibility of the results are considered. The effect of the specimen geometry on the bearing characteristics is considered. It is shown that increase both in the distance from the edge of the bearing specimen to the center of the hole for 1163T, VT6ch, 30KhGSA alloys and residual bearing deformation up to 6%, increase bearing strength characteristics.

Exploring M & Y Gasket Factors and Their Degree of Correlation With Proposed PVRC Gasket Factors

2017 ◽  
Author(s):  
Dale A. Rice ◽  
A. Fitzgerald Waterland ◽  
Anita R. Bausman
Keyword(s):  
Room Temperature ◽  
Test Procedure ◽  
Test Methods ◽  
Test Method ◽  
Initial Assessment ◽  
Operating Pressure ◽  
Test Standards ◽  
Section Viii ◽  
Yield Factor ◽  
Flexible Graphite

The well-known gasket factors, m & y were introduced in 1943 as per ASME Boiler and Pressure Vessel Code, Section VIII, Division 1 for purposes of flange design. The test procedure for determining these factors, ASTM Standard F586, was published in 1979 but then ultimately withdrawn in 1998 with the assumption that these test standards would be replaced by a new test method and with it the generation of improved gasket constants. The original m & y constants had several shortcomings including the fact that many of the listed values assumed asbestos fiber gaskets while new gasket materials such as PTFE (polytetrafluoroethylene) and FG (flexible graphite) were not addressed. Additionally, gasket manufacturers were allowed to publish m and y values for their own specific gasket materials and styles using their own test methods, thus dispensing with industry-wide standardization. ASTM Method F3149-15, “Standard Practice for Determining the Maintenance Factor (m) and Yield Factor (y) Loading Constants Applicable to Gasket Materials and Designs” represents an improvement over F586 but is not linked to standardized tightness levels. The proposed PVRC method with a new set of gasket constants is based on a load versus leakage test standard known as ROTT (Room Temperature Tightness Test). Following the ROTT method, ASTM WK39360, “New Test Method for Leak Rates Versus Y Stresses and M Factors for Gaskets derived from the Room Temperature Test Practice”, is being contemplated. This paper provides a review of the past inconsistencies of m & y values as published as well as an initial assessment of the degree of correlation between m & y values and tightness calculations achieved through the use of a previously documented fugitive emissions calculator for gasket materials which makes use of published ROTT data, and the operating pressure, flange NPS, gasket stress, and other inputs.

Hot Pin Pull Method – New Test Procedure for the Adhesion Measurement for 3D-MID

2014 ◽  
Vol 1038 ◽  
pp. 115-120 ◽  
Author(s):  
Christian Goth ◽  
Thomas Kuhn ◽  
Gerald Gion ◽  
Jörg Franke
Keyword(s):  
Test Procedure ◽  
Test Methods ◽  
Test Method ◽  
Testing System ◽  
Adhesion Test ◽  
Metallic Structures ◽  
Adhesion Measurement ◽  
Molded Interconnect Devices ◽  
Unsolved Issue

The adhesion test of metallic structures on MID (Molded Interconnect Devices) parts is an unsolved issue. So far no method really works reliably. The test methods which are conventionally used are the pull-off test and the shear-test. Both show large standard deviation and the reproducibility is not assured. Nordson DAGE has introduced the new micro-material testing system 4000Plus. This device enables a new test method for the determination of the adhesion strength of MID structures using the hot pin pull (hot bump pull) method. Copper pins (tinned or untinned) are heated up with a user defined temperature profile, soldered to a metallized structure on the MID and then removed vertically upward, while the force is recorded. In this contribution investigations with this new test method are presented.

scholarly journals Leaching of nanoparticles from nano-enabled products for the protection of cultural heritage surfaces: a review

2021 ◽  
Vol 33 (1) ◽  
Author(s):  
Andrea Brunelli ◽  
Loris Calgaro ◽  
Elena Semenzin ◽  
Virginia Cazzagon ◽  
Elisa Giubilato ◽  
...  
Keyword(s):  
Cultural Heritage ◽  
Human Health ◽  
Protective Coatings ◽  
Waste Water Treatment ◽  
Test Methods ◽  
Standard Test ◽  
Engineered Nanoparticles ◽  
Test Method ◽  
Surface Areas ◽  
Materials Used

AbstractThe development of highly innovative techniques and technologies to enhance performance and technical sustainability of materials used in the field of cultural heritage conservation is providing conservators with innovative nanocomposites materials, including protective coatings, by merging the performances of engineered nanoparticles (NPs) with conventional chemicals. However, the human health and environmental risks that may potentially arise from these new materials are still largely unknown, requiring an adequate assessment and management along their entire life cycle. Concerns could emerge due to the leaching of the material containing NPs or of the NPs alone, especially during their use (exposure of the treated object to, e.g., heavy or acid rain) and disposal (when the wasted product is processed in, e.g., waste water treatment plants). To date, no standard leaching test methods have been specifically developed for nano-enabled products, with the consequent lack of data on the NPs potential exposure also in the field of cultural heritage. Therefore, an extensive review over the last 10 years by querying to the Scopus database “nanoparticles”, “leaching” and “coatings” has been herein reported to clearly highlight (i) the standard test methods used or adapted to estimate the NPs leaching from nano-based coatings; (ii) the available studies in which the NPs leaching from nano-based coatings was estimated without following any specific standard test method; (iii) the works focusing on other nanocomposite materials performances than leaching, in which standard test methods were applied, potentially useful to indirectly estimate NPs leaching. All the information gathered by this bibliographic search have been used to identify the most promising leaching tests for NPs estimation to be applied in the field of cultural heritage, especially for both large, e.g., building façades, and small, e.g., bronze works of art, surface areas from which the leaching of nano-based materials could be significant in terms of human health and ecological risks, based also on the (eco)toxicity of the leachate. The derived information can thus ultimately support effective risk management of innovative nano-enabled products, including the implementation of Safe by Design approaches.

scholarly journals Evaluation of Laboratory Methods of Determination of SBS Content in Polymer-Modified Bitumens

Materials ◽  
2020 ◽  
Vol 13 (22) ◽  
pp. 5237
Author(s):  
Maria Ratajczak ◽  
Artur Wilmański
Keyword(s):  
Building Materials ◽  
Test Procedure ◽  
Test Methods ◽  
Construction Sites ◽  
Modified Bitumen ◽  
Codes Of Practice ◽  
Materials Used ◽  
Industrial Samples ◽  
Styrene Butadiene

The article deals with the issue of determination of the content of SBS (Styrene-Butadiene-Styrene) in polymer-modified bitumens (PMBs). The effect of SBS copolymer on the physical and rheological properties of bitumens has been thoroughly investigated and widely described in the literature. Condition surveys of structures and evaluation of the properties of materials used at construction sites have become a huge challenge for construction engineering. Determination of the content of SBS modifier in various building materials (asphalt mixtures and bituminous waterproofing compounds) is a good example in this respect. Based on the laboratory tests, mid-infrared spectroscopy was found to be the most effective analytical method. It can be used for easy detection of the presence of SBS in a modified bitumen. However, quantitative analysis is an issue that calls for research. Currently, there are no standard guidelines, whether national or European, that would regulate the method of testing. Three test methods were assessed in this study: the AASHTO T302–15 standard method and two Australian methods described in codes of practice (T521 and Q350) developed by the local authorities, which define a standard way of determining the amount of SBS in polymer-modified bitumens. The tests were carried out on standard controls and samples sourced from the industry. The above-mentioned test methods were assessed in terms of accuracy of determination, reliability of results obtained on the industrial samples, level of complexity of the test procedure, sample preparation techniques and the type of the required reagents.

Methodological Issues in Testing Comprehension of Safety Symbols

2002 ◽  
Vol 46 (19) ◽  
pp. 1744-1747 ◽  
Author(s):  
Mary F. Lesch ◽  
Jamie R. McDevitt
Keyword(s):  
Test Procedure ◽  
Multiple Choice ◽  
Test Methods ◽  
Test Method ◽  
Choice Test ◽  
Attractive Alternative ◽  
Multiple Choice Test ◽  
Methodological Issues ◽  
Scoring Method ◽  
Multiple Trials

Safety symbols must be tested prior to use to ensure that they are adequately understood, as failures to communicate can result in injury or death. However, factors other than symbol quality influence assessed comprehension level: These include test method, scoring method, as well as availability of context. Open-ended and multiple-choice test methods are compared and contrasted on a number of dimensions including ease of construction, administration, and scoring. While use of an open-ended test procedure is generally recommended, it is proposed that a modified multiple-choice test, in which alternatives are assessed across multiple trials, is an attractive alternative.

TEST METHOD FOR A COMPOSITE REINFORCING ROD ON THE BASE OF BASALT COMPLEX THREAD

2021 ◽  
Vol 93 (1) ◽  
pp. 50-64
Author(s):  
L.U. STUPISHIN ◽  
◽  
A.V. MASALOV ◽  
E.V. SAVELEVA ◽  
◽  
...  
Keyword(s):  
Bearing Capacity ◽  
Test Procedure ◽  
Test Methods ◽  
Testing Equipment ◽  
Test Method ◽  
Normative Documents ◽  
General Lack ◽  
Test Methodology ◽  
Twisted Yarn

The paper considers issues of construction of test methods and testing of basalt rods proposed by the authors. A basalt rod is a bundle of twisted basalt roving threads packed in an epoxy laminate. Due to the lack of analogues, a methodology for testing reinforcing rods using existing testing machines is being developed. The analysis of Russian and foreign normative documents, which could form the basis of the test methodology, was carried out. A general lack of testing equipment is noted, leading to the destruction of the basalt twisted yarn in the grippers prior to testing. A test procedure is proposed and the results of experiments are presented, which make it possible to assess the bearing capacity of a reinforced specimen. Conclusions and recommendations for testing structures reinforced with basalt rods - laminates are presented.

An evaluation of ECT sample height for small flute board grades and Box Manufacturer’s Certification compliance

TAPPI Journal ◽  
2009 ◽  
Vol 8 (6) ◽  
pp. 24-28
Author(s):  
CORY JAY WILSON ◽  
BENJAMIN FRANK
Keyword(s):  
Compressive Strength ◽  
Compressive Load ◽  
Test Sample ◽  
Test Methods ◽  
Test Method ◽  
Initial Development ◽  
Sample Height ◽  
Relationship Of ◽  
The Relationship ◽  
Corrugated Fiberboard

TAPPI test T811 is the specified method to ascertain ECT relative to box manufacturer’s certification compliance of corrugated fiberboard under Rule 41/ Alternate Item 222. T811 test sample heights were derived from typical board constructions at the time of the test method’s initial development. New, smaller flute sizes have since been developed, and the use of lighter weight boards has become more common. The T811 test method includes sample specifications for typical A-flute, B-flute, and C-flute singlewall (and doublewall and triplewall) structures, but not for newer thinner E-flute or F-flute structures. This research explores the relationship of ECT sample height to measured compressive load, in an effort to determine valid E-flute and F-flute ECT sample heights for use with the T811 method. Through this process, it identifies challenges present in our use of current ECT test methods as a measure of intrinsic compressive strength for smaller flute structures. The data does not support the use of TAPPI T 811 for ECT measurement for E and F flute structures, and demonstrates inconsistencies with current height specifi-cations for some lightweight B flute.

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