Home About us Contact
|
Home About us Contact | ||
|
|
||
Test Facility (test + facility)
Selected AbstractsAnalysis of leakage currents in photovoltaic modules under high-voltage bias in the field,PROGRESS IN PHOTOVOLTAICS: RESEARCH & APPLICATIONS, Issue 1 2002J. A. del Cueto As photovoltaic modules become more widely disseminated in high-power or utility-power applications, their ability to withstand high voltage relative to ground becomes a reliability issue. Long-term effects of exposure to high-voltage stress in the field are investigated. Starting in early 1998, four commercially available PV modules inaugurated the high-voltage stress test at the Outdoor Test Facility at NREL. Modules representing both crystalline and amorphous silicon technologies were deployed on the high-voltage stress testbed located outdoors in order to simulate and assess operation in high-voltage array configurations. They were biased at positive and negative polarity 600 V at all times,except for 1 min at noon each day, when they were subjected to 2200 V bias,and their leakage currents to ground were monitored continuously. The ubiquitous effects of moisture on leakage conductance are analyzed. Module leakage conductance is found to be thermally activated with a characteristic energy that depends on relative humidity. Separate current paths likely responsible for leakage conductance are analyzed and identified at opposite ends of the relative humidity range. Leakage current data are integrated against time to arrive at accumulated charge due to long-term, high-voltage exposure. Published in 2002 by John Wiley & Sons, Ltd. [source] ARTICULATED CONCRETE BLOCK STABILITY TESTING,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 1 2001Steven R. Abt ABSTRACT: An articulated concrete block revetment system was developed by the U.S. Army Corps of Engineers to test and evaluate the practicability of the protocols for overtopping and channelized flow conditions. Test facilities were constructed, prototype articulated concrete blocks were fabricated and installed into the facilities, and the blocks were tested using the established protocols. The test results indicated that both the overtopping and channel flow tests yielded similar results: the blocks reached a point of instability at approximately the same velocity and shear stresses. The similar test results indicate that only one protocol is required to evaluate an articulated concrete block system. It was demonstrated that both protocols can be effectively conducted. It is recommended that the overtopping test be adapted as a standard test procedure because of its reduced construction costs and its efficiency compared to the channelized test. [source] The journey of Indian GLP programme,looking back and forwardQUALITY ASSURANCE JOURNAL, Issue 1 2009V. Amalan Stanley Abstract The Indian GLP (Good Laboratory Practice) compliance monitoring programme has successfully brought the task of implementing the programme to the foreground where full OECD (Organization for Economic Cooperation and Development) membership is about to happen. It has been a long journey, more than five years for the programme to arrive at this juncture, succeeding through sheer commitment and will of the Science and Technology initiatives under which the programme has been implemented. Considering the spontaneous and natural challenges that are bound to make the effort of implementing the GLP compliance programme tougher for any country, the progress made by the Indian GLP programme can be considered very rapid. Though the dawn of full OECD membership for the Indian GLP programme is imminent the paper deals with the details of the journey it has traveled so far and the challenges ahead, commending the commitment of the efforts of the GLP MA (Monitoring Authority) as well as the preparedness of the test facilities. This paper discusses the GLP policy aspects that favoured the growth of the programme among non-member adherents, such as the allowance for getting GLP certification by GLP MA abroad. It also deals with the challenge of harmonizing the policies of the internal agencies that have direct influence on the implementation of the GLP programme, other than legalizing the GLP aspects as there are various government departments in India dealing with the regulatory aspects of specific drug products for human use or that are of chemical in origin. There are data requirements made mandatory by these institutions on pre-clinical or non-clinical safety evaluation of those products, which invariably necessitate studies conducted in compliance with the principles of GLP. The paper concludes with the emphasis that there is a primary need for harmony as well as legal or judicial underpinnings under the umbrella of a national GLP Monitoring Authority, a gray area to be essentially tackled with foresight, to earn credibility on the international front. Copyright © 2009 John Wiley & Sons, Ltd. [source] Good Laboratory Practice (GLP), guidelines for the validation of computerised systems,QUALITY ASSURANCE JOURNAL, Issue 3-4 2007Peter M. Esch Abstract The aim of this document is to provide guidance on the validation of computerised systems, compliant with Good Laboratory Practice (GLP). It specifies more precisely the procedures to follow in carrying out validations of computerised systems. It intends to help test facilities promote a common standard. However, the test facility management may use different approaches, as long as they are in compliance with the Organisation for Economic Co-operation and Development (OECD) Principles of GLP [1]. The extent of a validation may vary depending on the complexity of the computerised system. In any case the validation should demonstrate that the computerised system is suitable for its intended purpose. The Arbeitsgruppe Informations-Technologie (AGIT) is a working group consisting of representatives from Swiss industry and Swiss GLP monitoring authorities with the aim of proposing procedures that are practical for use in test facilities fulfilling GLP regulatory requirements. These guidelines have been adapted to current practices and replace those issued in June 2000. Copyright © 2008 John Wiley & Sons, Ltd. [source] Good Laboratory Practice (GLP);QUALITY ASSURANCE JOURNAL, Issue 1 2006initialling; The aim of the present document is to provide guidance on the Good Laboratory Practice (GLP)-compliant acquisition and processing of electronic raw data. The life cycle of electronic raw data and their related meta data from the data acquisition to the data processing and the generation of results is shown. The different roles and responsibilities for data entry, data editing, data approval, and data freezing are specified. The requirements for time stamps, audit trails, and the identification of acting persons are described. Furthermore different levels of laboratory instrument integration in a LIMS are discussed. This document is intended to aid test facilities, and to promote the use of a common standard, but it should not be considered as a legally binding document. These guidelines may evolve with experience over the next few years and may be modified to reflect interpretations made by other Organisation for Economic Co-operation and Development (OECD) member countries. The present guidelines were prepared by the Working Group on Information Technology (Arbeitsgruppe Informationstechnologie, AGIT). This group consists of representatives from Swiss industry and the Swiss GLP monitoring authorities. Copyright © 2006 John Wiley & Sons, Ltd. [source] Active tendon control of cable-stayed bridges: a large-scale demonstrationEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 7 2001Frédéric Bossens This paper presents a strategy for active damping of cable structures, using active tendons. The first part of the paper summarizes the theoretical background: the control law is briefly presented together with the main results of an approximate linear theory which allows the prediction of closed-loop poles with a root locus technique. The second part of the paper reports on experimental results obtained with two test structures: the first one is a small size mock-up representative of a cable-stayed bridge during the construction phase. The control of the parametric vibration of passive cables due to deck vibration is demonstrated. The second one is a 30 m long mock-up built on the reaction wall of the ELSA test facility at the JRC Ispra (Italy); this test structure is used to demonstrate the practical implementation of the control strategy with hydraulic actuators. Copyright © 2001 John Wiley & Sons, Ltd. [source] Numerical simulation of model scramjet combustor flowfieldHEAT TRANSFER - ASIAN RESEARCH (FORMERLY HEAT TRANSFER-JAPANESE RESEARCH), Issue 5 2007Yuan-Guang Wang Abstract A new concept has been raised and adopted in this paper to enlarge the scope of the two-dimensional model particularly for the purpose of dealing with three-dimensional normal injection cases. Meanwhile, the method has a very good performance for its short cyclic period. The new idea was realized through special resolution with continuity equations; i.e., mass flow was directly added in the source term of the continuity equation. To prove the robustness of this illuminating method, comparisons using calculations were carried out, and the results are satisfactory. A model scramjet combustor tested on the free-jet scramjet test facility was illustrated and underwent numerical calculations with the two-dimensional program, adopting the above simplified injecting method. To simulate the chemical reaction process in the scramjet tunnel, a five-species, single-step reaction model was introduced in the calculation process. This research presents the major aerodynamic parameters and components of mass fraction distribution within the model combustor channel, which made it easy to observe and analyze the flowfield. Finally, wall pressure comparisons between the numerical and experimental results were carried out to verify the accuracy of the calculation model. © 2007 Wiley Periodicals, Inc. Heat Trans Asian Res, 36(5): 295, 302, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20159 [source] URANS computations for an oscillatory non-isothermal triple-jet using the k,, and second moment closure turbulence modelsINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 9 2003M. Nishimura Abstract Low Reynolds number turbulence stress and heat flux equation models (LRSFM) have been developed to enhance predictive capabilities. A new method is proposed for providing the wall boundary condition for dissipation rate of turbulent kinetic energy, ,, to improve the model capability upon application of coarse meshes for practical use. The proposed method shows good agreement with accepted correlations and experimental data for flows with various Reynolds and Prandtl numbers including transitional regimes. Also, a mesh width about 5 times or larger than that used in existing models is applicable by using the present boundary condition. The present method thus enhanced computational efficiency in applying the complex turbulence model, LRSFM, to predictions of complicated flows. Unsteady Reynolds averaged Navier,Stokes (URANS) computations are conducted for an oscillatory non-isothermal quasi-planar triple-jet. Comparisons are made between an experiment and predictions with the LRSFM and the standard k,, model. A water test facility with three vertical jets, the cold in between two hot jets, simulates temperature fluctuations anticipated at the outlet of a liquid metal fast reactor core. The LRSFM shows good agreement with the experiment, with respect to mean profiles and the oscillatory motion of the flow, while the k,, model under-predicts the mixing due to the oscillation, such that a transverse mean temperature difference remains far downstream. Copyright © 2003 John Wiley & Sons, Ltd. [source] Performance characteristics and modelling of a micro gas turbine for their integration with thermally activated cooling technologiesINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 2 2007Adrián Vidal Abstract We have developed a simple model of a micro gas turbine system operating at high ambient temperatures and characterized its performance with a view to integrating this system with thermally activated cooling technologies. To develop and validate this model, we used experimental data from the micro gas turbine test facility of the CREVER research centre. The microturbine components were modelled and the thermodynamic properties of air and combustion gases were estimated using a commercial process simulator. Important information such as net output power, microturbine fuel consumption and exhaust gas mass flow rate can be obtained with the empirical correlations we have developed in this study. This information can be useful for design exhaust gas fired absorption chillers. Copyright © 2006 John Wiley & Sons, Ltd. [source] Improved design of mantle tanks for small low flow SDHW systemsINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 12 2006Simon Furbo Abstract Side-by-side tests of two small low flow solar domestic hot water (SDHW) systems based on mantle tanks have been carried out under the same test conditions in a laboratory test facility. The systems are identical with exception of the mantle tanks. One of the mantle tanks has the mantle inlet port located at the top of the mantle and the other mantle tank has the mantle inlet port moved 0.175 m down from the top of the mantle. The thermal performance is almost the same for the two systems in the measuring period of 252 days. The solar fractions were 0.66 and 0.68 for the two systems. The tests showed also that the system with the low mantle inlet perform better than the system with the high mantle inlet in periods with low solar fractions, that is in less sunny periods. Further, calculations with a simulation model for low flow SDHW systems based on mantle tanks showed that mantle tanks currently marketed can be greatly improved by relatively simple design changes: increasing the height/diameter ratio, reducing the mantle height and increasing the insulation thickness on the sides of the tank. Copyright © 2006 John Wiley & Sons, Ltd. [source] On the steady-state modelling of a two-stage evaporator systemINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 10 2001M. N. A. Hawlader Abstract We develop and validate against experimental measurements a steady-state two-stage flooded refrigerant evaporator model for a heat pump drying system. A prototype two-stage heat pump dryer test facility was designed, built and instrumented to provide the required measurements for the validation of the model. Repeatability and data quality tests were conducted to evaluate the accuracy of measurements. Experimental data could be reproduced to within ±6.5 per cent of replicated air and refrigerant side measurements for the same evaporator's air inlet conditions while the discrepancy of energy balance at the air-side and refrigerant-side was observed to be within ±8.9 per cent. The two-stage evaporator model predicted the air-side total heat and latent heat transfer of the two-stage evaporator to within (,6.3 per cent, 7.6 per cent) and (,11.5 per cent, 9.5 per cent), respectively. On the refrigerant-side, the model enabled the calculation of the degree of superheat to within (,10.6 per cent, 1.7 per cent). The model has shown that there is significant improvement in the heat recovered from a two-stage evaporator system compared to a single evaporator system. In addition, the model demonstrated that the improvement in total heat recovery could be as high as 40 per cent over its base-value when the latent to total load at the two-stage evaporator is increased. Copyright © 2001 John Wiley & Sons, Ltd. [source] Deflagration and detonation of ethylene oxide vapor in pipelinesPROCESS SAFETY PROGRESS, Issue 3 2000Paul Thibault Pure ethylene oxide (EO) vapor may propagate decomposition flames through pipe above certain minimum conditions of temperature, pressure and pipe diameter. Flame propagation was studied in both closed and vented 5 cm (2-inch) pipe and closed 30 cm (12-inch) pipe. Flame progression in closed pipe was irregular and proceeded in pulsed stages. A possible mechanism involves preferential flame propagation at the pipe roof accompanied by periodic autodecomposition of EO accumulated in hot products behind the flame front, such accumulation probably being augmented by liquid EO condensed on the pipe walls ahead of the expanding flame system. Flames propagated 15 m (50 ft) through horizontal 5 cm pipe at 70°C and initial pressures , 4.3 bar (62 psia). In a series of 30 cm pipe tests employing low-energy ignition and otherwise increasingly severe conditions, a deflagration-to-detonation transition (DDT) occurred, partially destroying the test equipment. A new test facility was set up to confirm the ability of EO to propagate detonations in 30 cm pipe and to further investigate the phenomenon. Two EO detonations at 2.9 bar and one at 3.5 bar were directly initiated via the strong shocks from hydrogen-oxygen detonations. Based on a spectrum analysis of the pressure histories, the two detonations at 2.9 bar were probably marginal and propagated in a single spin detonation mode. At 3.5 bar, the pressure history suggests that the detonation propagated in a two-head detonation mode near the end of the 24 m test section. [source] Does the MAD system make test facilities mad?QUALITY ASSURANCE JOURNAL, Issue 4 2006V. Amalan Stanley Abstract There needs more clarity in ad hoc Good Laboratory Practice (GLP) certification conferred to test facilities of non-member economies. There is a similar kind of issue with the ,GLP status' of the test data generated by a test facility that has been conferred GLP certification by the country that is only a provisional adherent. In both cases, the objective of the Mutual Acceptance of Data (MAD) system will not be fulfilled if the answer is ,no'. Copyright © 2006 John Wiley & Sons, Ltd. [source] GLPs and medical devicesQUALITY ASSURANCE JOURNAL, Issue 2 2002Linda Palagi Lynn Abstract Applying Good Laboratory Practice (GLP) regulations to studies of medical devices and combination products (drug/device products) presents some unique challenges. The complexity of medical devices , which may be internal, external, or composed of many intricate parts including software, hardware, or drugs to perform their intended task , requires interpretation of the regulations. Further, the dynamics of the conduct of non-clinical laboratory studies for medical devices can be quite complex often involving a team of scientists, engineers, computer specialists, technicians, veterinarians, physicians, pathologists and equipment from both the test facility and sponsor. This article highlights areas of the GLP regulations and provides information and suggestions for GLP compliance for medical device studies. Copyright © 2002 John Wiley & Sons, Ltd. [source] Influence of oil-atomized air on flow and combustion characteristics in a 300 MWe down-fired boilerASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 3 2010Zhengqi Li Abstract A method of admitting oil-atomized air into a furnace to adjust coal combustion in a down-fired boiler is described. Experiments with a small-scale furnace simulating a down-fired, pulverized-coal, 300-MWe utility boiler were carried out at a single-phase test facility to investigate the influence of oil-atomized air on the aerodynamic field in the furnace. With the acceleration of oil by secondary air, the primary air/fuel can reach a more distant position with respect to the burner nozzle and the volume of the recirculation zone shrinks. Industrial experiments were also performed in a 300-MWe full-scale boiler. The gas temperature distribution along the primary air/fuel flow in the furnace and the gas components in the near-wall region were measured with the dampers of the oil-atomized air box open and closed. When open, the oil-atomized air does not impede the ignition of the primary air/fuel and can carry the primary air/fuel to a position much deeper in the furnace, resulting in a lowered carbon content in the fly ash. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd. [source] Schallfeldsimulation mit Spiegelquellen , Eine Planungshilfe für reflexionsarme RäumeBAUPHYSIK, Issue 4 2009Xueqin Zha Prof. Schall; Berechnungsverfahren; sound protection and acoustics; calculation methods Abstract Konventionelle Auslegungen von akustischen Freifeldräumen nach ISO 3745 sind häufig mit Risiken behaftet, weil die übliche Annahme eines Absorptionsgrades bei senkrechtem Schalleinfall von 99 % herkömmlicher faseriger oder poröser Auskleidungen von Fall zu Fall weder notwendig noch ausreichend sein kann. Es wird ein Simulationsprogramm vorgestellt, das mit der phasenrichtigen Überlagerung der Schallwellen einer realen Punkt- und einer Serie von Spiegelquellen arbeitet, welche die unvollständig absorbierenden Begrenzungsflächen des Raumes ersetzen. Damit werden verschiedene Einflüsse aufgezeigt, die die Freifeldeigenschaften ebenso stark beeinflussen können wie der Absorptionsgrad der Auskleidung. So lässt sich bereits in einem frühen Planungsstadium mehr Sicherheit über die Qualität eines Akustik-Prüfstandes zur Bestimmung von Schallleistung, Spektrum und Richtcharakteristik technischer Schallquellen gewinnen. Sound field simulation by image sources , A design tool for anechoic rooms. Conventional designs of anechoic rooms according to ISO 3745 often bear risks since the usual assumption of an absorption coefficient at normal incidence of 99 % of traditional fibrous or porous claddings may be not necessary in one case but insufficient in another. A simulation program is presented which is based on the wave interferences of the sound from a real point source and a number of image sources which replace imperfectly absorbing bounding surfaces. Its application demonstrates various effects which can influence the free-field characteristics to the same extent as the absorption of the cladding. By this one may gain more confidence , at an early stage of the planning process , in the quality of an acoustic test facility for the determination of sound power, spectrum and directivity of technical sound sources. [source] | |||||||||||||