WorldWideScience

Sample records for evacuated tubular collectors

  1. Solar Heating Systems with Evacuated Tubular Solar Collector

    DEFF Research Database (Denmark)

    Qin, Lin; Furbo, Simon

    1998-01-01

    Recently different designed evacuated tubular solar collectors were introduced on the market by different Chinese companies. In the present study, investigations on the performance of four different Chinese evacuated tubular collectors and of solar heating systems using these collectors were...... carried out, employing both laboratory test and theoretical calculations. The collectors were tested in a small solar domestic hot water (SDHW) system in a laboratory test facility under realistic conditions. The yearly thermal performance of solar heating systems with these evacuated tubular collectors......, as well as with normal flat-plate collectors was calculated under Danish weather conditions. It is found that, for small SDHW systems with a combi tank design, an increase of 25% -55% net utilized solar energy can be achieved by using these evacuated tubular collectors instead of normal flat...

  2. Theoretical flow investigations of an all glass evacuated tubular collector

    DEFF Research Database (Denmark)

    Shah, Louise Jivan; Furbo, Simon

    2007-01-01

    Heat transfer and flow structures inside all glass evacuated tubular collectors for different operating conditions are investigated by means of computational fluid dynamics. The investigations are based on a collector design with horizontal tubes connected to a vertical 14 manifold channel. Three...... the highest efficiency, the optimal inlet flow rate was around 0.4-1 kg/min, the flow structures in the glass tubes were relatively uninfluenced by the inlet flow rate, Generally, the results showed only small variations in the efficiencies. This indicates that the collector design is well working for most...

  3. VALIDATION OF SIMULATION MODELS FOR DIFFERENTLY DESIGNED HEAT-PIPE EVACUATED TUBULAR COLLECTORS

    DEFF Research Database (Denmark)

    Fan, Jianhua; Dragsted, Janne; Furbo, Simon

    2007-01-01

    Differently designed heat-pipe evacuated tubular collectors have been investigated theoretically and experimentally. The theoretical work has included development of two TRNSYS [1] simulation models for heat-pipe evacuated tubular collectors utilizing solar radiation from all directions. One model...... coating on both sides. The input to the models is thus not a simple collector efficiency expression but the actual collector geometry. In this study, the TRNSYS models are validated with measurements for four differently designed heat-pipe evacuated tubular collectors. The collectors are produced...

  4. Thermal performance of an open thermosyphon using nanofluid for evacuated tubular high temperature air solar collector

    International Nuclear Information System (INIS)

    Liu, Zhen-Hua; Hu, Ren-Lin; Lu, Lin; Zhao, Feng; Xiao, Hong-shen

    2013-01-01

    Highlights: • A novel solar air collector with simplified CPC and open thermosyphon is designed and tested. • Simplified CPC has a much lower cost at the expense of slight efficiency loss. • Nanofluid effectively improves thermal performance of the above solar air collector. • Solar air collector with open thermosyphon is better than that with concentric tube. - Abstract: A novel evacuated tubular solar air collector integrated with simplified CPC (compound parabolic concentrator) and special open thermosyphon using water based CuO nanofluid as the working fluid is designed to provide air with high and moderate temperature. The experimental system has two linked panels and each panel includes an evacuated tube, a simplified CPC and an open thermosyphon. Outdoor experimental study has been carried out to investigate the actual solar collecting performance of the designed system. Experimental results show that air outlet temperature and system collecting efficiency of the solar air collector using nanofluid as the open thermosyphon’s working fluid are both higher than that using water. Its maximum air outlet temperature exceeds 170 °C at the air volume rate of 7.6 m 3 /h in winter, even though the experimental system consists of only two collecting panels. The solar collecting performance of the solar collector integrated with open thermosyphon is also compared with that integrated with common concentric tube. Experimental results show that the solar collector integrated with open thermosyphon has a much better collecting performance

  5. Characteristics of evacuated tubular solar thermal collector as input energy for cooling system at Universitas Indonesia

    Science.gov (United States)

    Alhamid, M. Idrus; Nasruddin, Aisyah, Nyayu; Sholahudin

    2017-03-01

    This paper discussed the use of solar thermal collector as an input energy for cooling system. The experimental investigation was undertaken to characterize solar collectors that have been integrated with an absorption chiller. About 62 modules of solar collectors connected in series and parallel are placed on the roof top of MRC building. Thermistors were used to measure the fluid temperature at inlet, inside and outlet of each collector, inside the water tank and ambient temperature. Water flow that circulated from the storage was measured by flow meter, while solar radiation was measured by a pyranometer that was mounted parallel to the collector. Experimental data for a data set was collected in March 2016, during the day time hours of 08:00 - 17:00. This data set was used to calculate solar collector efficiency. The results showed that in the maximum solar radiation, the outlet temperature that can be reached is about 78°C, the utilized energy is about 70 kW and solar collector has an efficiency of 64%. While in the minimum solar radiation, the outlet temperature that can be reached is about 53°C, the utilized energy is about 28 kW and solar collector has an efficiency of 43%.

  6. Advanced evacuated tube collectors

    Science.gov (United States)

    Schertz, W. W.; Hull, J. R.; Winston, R.; Ogallagher, J.

    1985-04-01

    The essence of the design concept for these new collectors is the integration of moderate levels of nonimaging concentration inside the evacuated tube itself. This permanently protects the reflection surfaces and allows the use of highly reflecting front surface mirrors with reflectances greater than 95%. Previous fabrication and long term testing of a proof-of-concept prototype has established the technical success of the concept. Present work is directed toward the development of a manufacturable unit that will be suitable for the widest possible range of applications. Design alternatives include scaling up the original prototype's tube diameter from 5 cm to 10 cm, using an internal shaped metal concentrating reflector, using a variety of profile shapes to minimize so-called gap losses and accommodate both single ended and double-ended flow geometries, and allowing the use of heat pipes for the absorber tube.

  7. Feasibility Study on the Use of a Solar Thermoelectric Cogenerator Comprising a Thermoelectric Module and Evacuated Tubular Collector with Parabolic Trough Concentrator

    Science.gov (United States)

    Miao, L.; Zhang, M.; Tanemura, S.; Tanaka, T.; Kang, Y. P.; Xu, G.

    2012-06-01

    We have designed a new solar thermoelectric cogeneration system consisting of an evacuated tubular solar collector (ETSC) with a parabolic trough concentrator (PTC) and thermoelectric modules (TEMs) to supply both thermal energy and electricity. The main design concepts are (1) the hot side of the TEM is bonded to the solar selective absorber installed in an evacuated glass tube, (2) the cold side of the TEM is also bonded to the heat sink, and (3) the outer circulated water is heated by residual solar energy after TEM generation. We present an example solar thermal simulation based on energy balance and heat transfer as used in solar engineering to predict the electrical conversion efficiency and solar thermal conversion efficiency for different values of parameters such as the solar insolation, concentration ratio, and TEM ZT values.

  8. Optimal nonimaging integrated evacuated solar collector

    Science.gov (United States)

    Garrison, John D.; Duff, W. S.; O'Gallagher, Joseph J.; Winston, Roland

    1993-11-01

    A non imaging integrated evacuated solar collector for solar thermal energy collection is discussed which has the lower portion of the tubular glass vacuum enveloped shaped and inside surface mirrored to optimally concentrate sunlight onto an absorber tube in the vacuum. This design uses vacuum to eliminate heat loss from the absorber surface by conduction and convection of air, soda lime glass for the vacuum envelope material to lower cost, optimal non imaging concentration integrated with the glass vacuum envelope to lower cost and improve solar energy collection, and a selective absorber for the absorbing surface which has high absorptance and low emittance to lower heat loss by radiation and improve energy collection efficiency. This leads to a very low heat loss collector with high optical collection efficiency, which can operate at temperatures up to the order of 250 degree(s)C with good efficiency while being lower in cost than current evacuated solar collectors. Cost estimates are presented which indicate a cost for this solar collector system which can be competitive with the cost of fossil fuel heat energy sources when the collector system is produced in sufficient volume. Non imaging concentration, which reduces cost while improving performance, and which allows efficient solar energy collection without tracking the sun, is a key element in this solar collector design.

  9. Investigation of Thermal Performance of Flat Plate and Evacuated Tubular Solar Collectors According to a New Dynamic Test Method

    DEFF Research Database (Denmark)

    Kong, Weiqiang; Wang, Zhifeng; Fan, Jianhua

    2012-01-01

    obtain fluid thermal capacitance in data processing. Then theoretical analysis and experimental verification are carried out to investigate influencing factors of obtaining accurate and stable second order term. A flat plate and ETC solar collector are compared using both the new dynamic method......A new dynamic test method is introduced. This so called improved transfer function method features on two new collector parameters. One is time term which can indicate solar collector's inner heat transfer ability and the other is a second order term of collector mean fluid temperature which can...... and a standard method. The results show that the improved function method can accurately and robustly estimate these two kinds of solar collectors....

  10. Performance Evaluation of a Demonstration System with PCM for Seasonal Heat Storage: Charge with Evacuated Tubular Collectors

    DEFF Research Database (Denmark)

    Englmair, Gerald; Furbo, Simon; Kong, Weiqiang

    with sunshine, the storage system performance was evaluated regarding charge with solar heat. It shows the system behavior during typical operation resulting from the control strategy. Heat transfer rates from the solar collector array (22.4 m2 aperture area) to the heat stores reached a peak of 19 kW, when PCM......A seasonal heat storage with phase change material (PCM) for a solar space heating and domestic hot water combisystem was tested in automated operation during charge with solar collectors. A water tank was operating as buffer heat storage. Based on measurements during a representative day...... temperatures were increasing with the state of charge. This is in contrast to maximization of solar yield. However, the energy conversion efficiency (65 %) of the collector array was satisfying. By considering pump electricity consumption, an overall performance ratio of 30.8 was obtained....

  11. Pathways toward a low cost evacuated collector system

    Science.gov (United States)

    Hull, J. R.; Schertz, W. W.; Allen, J. W.; Ogallagher, J. J.; Winston, R.

    The goal of widespread use of solar thermal collectors will only be achieved when they are proven to be economically superior to competing energy sources. Evacuated tubular collectors appear to have the potential to achieve this goal. An advanced evacuated collector using nonimaging concentration under development at the University of Chicago and Argonne can achieve a 50% seasonal efficiency at heat delivery temperatures in excess of 170C. The same collector has an optical efficiency so that low temperature performance is also excellent. In this advanced collector design all of the critical components are enclosed in the vacuum, and the collector has an inherently long lifetime. The current cost of evacuated systems is too high, mainly because the volume of production has been too low to realize economies of mass production. It appears that certain design features of evacuated collectors can be changed (e.g., use of heat pipe absorbers) so as to introduce new system design and market strategy options that can reduce the balance of system cost.

  12. A stationary evacuated collector with integrated concentrator

    Energy Technology Data Exchange (ETDEWEB)

    Snail, K.A.; O' Gallagher, J.J.; Winston, R.

    1984-01-01

    A comprehensive set of experimental tests and detailed optical and thermal models are presented for a newly developed solar thermal collector. The new collector has an optical efficiency of 65 per cent and achieves thermal efficiencies of better than 50 per cent at fluid temperatures of 200/sup 0/C without tracking the sun. The simultaneous features of high temperature operation and a fully stationary mount are made possible by combining vacuum insulation, spectrally selective coatings, and nonimaging concentration in a novel way. These 3 design elements are ''integrated'' together in a self containe unit by shaping the outer glass envelope of a conventional evacuated tube into the profile of a nonimaging CPC-type concentrator. This permits the use of a first surface mirror and eliminates the need for second cover glazing. The new collector has been given the name ''Integrated Stationary Evacuated Concentrator'', or ISEC collector. Not only is the peak thermal efficiency of the ISEC comparable to that of commercial tracking parabolic troughs, but projections of the average yearly energy delivery also show competitive performance with a net gain for temperatures below 200/sup 0/C. In addition, the ISEC is less subject to exposure induced degradation and could be mass produced with assembly methods similar to those used with fluorescent lamps. Since no tracking or tilt adjustments are ever required and because its sensitive optical surfaces are protected from the environment, the ISEC collector provides a simple, easily maintained solar thermal collector for the range 100-300/sup 0/C which is suitable for most climates and atmospheric conditions. Potential applications include space heating, air conditioning, and industrial process heat.

  13. Two Fixed, Evacuated, Glass, Solar Collectors Using Nonimaging Concentration

    Science.gov (United States)

    Garrison, John D.; Winston, Roland; O'Gallagher, Joseph; Ford, Gary

    1984-01-01

    Two fixed, evacuated, glass solar thermal collectors have been designed. The incorporation of nonimaging concentration, selective absorption and vacuum insulation into their design is essential for obtaining high efficiency through low heat loss, while operating at high temperatures. Nonimaging, approximately ideal concentration with wide acceptance angle permits solar radiation collection without tracking the sun, and insures collection of much of the diffuse radiation. It also minimizes the area of the absorbing surface, thereby reducing the radiation heat loss. Functional integration, where different parts of these two collectors serve more than one function, is also important in achieving high efficiency, and it reduces cost.

  14. Evacuated, displacement compression mold. [of tubular bodies from thermosetting plastics

    Science.gov (United States)

    Heier, W. C. (Inventor)

    1974-01-01

    A process of molding long thin-wall tubular bodies from thermosetting plastic molding compounds is described wherein the tubular body lengths may be several times the diameters. The process is accomplished by loading a predetermined quantity of molding compound into a female mold cavity closed at one end by a force mandrel. After closing the other end of the female mold with a balance mandrel, the loaded cavity is evacuated by applying a vacuum of from one-to-five mm pressure for a period of fifteen-to-thirty minutes. The mold temperature is raised to the minimum temperature at which the resin constituent of the compound will soften or plasticize and a pressure of 2500 psi is applied.

  15. Thermal performance of evacuated tube heat pipe solar collector

    Science.gov (United States)

    Putra, Nandy; Kristian, M. R.; David, R.; Haliansyah, K.; Ariantara, Bambang

    2016-06-01

    The high fossil energy consumption not only causes the scarcity of energy but also raises problems of global warming. Increasing needs of fossil fuel could be reduced through the utilization of solar energy by using solar collectors. Indonesia has the abundant potential for solar energy, but non-renewable energy sources still dominate energy consumption. With heat pipe as passive heat transfer device, evacuated tube solar collector is expected to heat up water for industrial and home usage without external power supply needed to circulate water inside the solar collector. This research was conducted to determine the performance of heat pipe-based evacuated tube solar collector as solar water heater experimentally. The experiments were carried out using stainless steel screen mesh as a wick material, and water and Al2O3-water 0.1% nanofluid as working fluid, and applying inclination angles of 0°, 15°, 30°, and 45°. To analyze the heat absorbed and transferred by the prototype, water at 30°C was circulated through the condenser. A 150 Watt halogen lamp was used as sun simulator, and the prototype was covered by an insulation box to obtain a steady state condition with a minimum affection of ambient changes. Experimental results show that the usage of Al2O3-water 0.1% nanofluid at 30° inclination angle provides the highest thermal performance, which gives efficiency as high as 0.196 and thermal resistance as low as 5.32 °C/W. The use of nanofluid as working fluid enhances thermal performance due to high thermal conductivity of the working fluid. The increase of the inclination angle plays a role in the drainage of the condensate to the evaporator that leads to higher thermal performance until the optimal inclination angle is reached.

  16. Low-cost evacuated-tube solar collector. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Beecher, D. T.

    1981-02-10

    A prototype design for an evacuated tube air cooled solar collector module has been completed. A product cost study, based on the production of 60,000 of the prototype modules per year (approx. 1,000,000 square feet annually), estimates that the module as shipped would have a cost at inventory of $7.09 to $7.40 per square foot of aperture. Computer programs were developed to predict the optical and thermal performance of the module. Antireflective coatings (porous aluminum oxide) which could be formed by spraying or dipping were demonstrated but degraded more rapidly when exposed to a high humidity ambient than acid etched films. A selective black chromium oxide multi-layered graded film was vapor deposited which had an absorptivity of about 0.9 and an emissivity of 0.03. When the film was heated to temperatures of 400/sup 0/C in a gettered vacuum for as little as 24 hours, however, irreversible changes took place both between and within coating layers which resulted in ..cap alpha.. decreasing to about 0.73 and epsilon increasing to 0.14. The product cost studies indicate that module design changes are warranted to reduce product cost prior to tooling for production.

  17. A new desalination system using a combination of heat pipe, evacuated tube and parabolic trough collector

    International Nuclear Information System (INIS)

    Jafari Mosleh, H.; Jahangiri Mamouri, S.; Shafii, M.B.; Hakim Sima, A.

    2015-01-01

    Highlights: • A new desalination uses a combination of heat pipe and parabolic trough collector. • A twin-glass evacuated tube is used to decrease the thermal losses from heat pipe. • Adding oil into the space between heat pipe and tube collector enhances the yield. • The yield and efficiency reach up to 0.933 kg/(m 2 h) and 65.2%, respectively. - Abstract: The solar collectors have been commonly used in desalination systems. Recent investigations show that the use of a linear parabolic trough collector in solar stills can improve the efficiency of a desalination system. In this work, a combination of a heat pipe and a twin-glass evacuated tube collector is utilized with a parabolic trough collector. Results show that the rate of production and efficiency can reach to 0.27 kg/(m 2 h) and 22.1% when aluminum conducting foils are used in the space between the heat pipe and the twin-glass evacuated tube collector to transfer heat from the tube collector to the heat pipe. When oil is used as a medium for the transfer of heat, filling the space between heat pipe and twin-glass evacuated tube collector, the production and efficiency can increase to 0.933 kg/(m 2 h) and 65.2%, respectively

  18. Performance optimization of evacuated tube collector for solar cooling of a house in hot climate

    Science.gov (United States)

    Ghoneim, Adel A.

    2018-02-01

    Evacuating the space connecting cover and absorber significantly improves evacuated tube collector (ETC) performance. So, ETCs are progressively utilised all over the world. The main goal of current study is to explore ETC thermal efficiency in hot and severe climate like Kuwait weather conditions. A collector test facility was installed to record ETC thermal performance for one-year period. An extensively developed model for ETCs is presented, employing complete optical and thermal assessment. This study analyses separately optics and heat transfer in the evacuated tubes, allowing the analysis to be extended to different configurations. The predictions obtained are in agreement with experimental. The optimum collector parameters (collector tube length and diameter, mass flow rate and collector tilt angle) are determined. The present results indicate that the optimum tube length is 1.5 m, as at this length a significant improvement is achieved in efficiency for different tube diameters studied. Finally, the heat generated from ETCs is used for solar cooling of a house. Results of the simulation of cooling system indicate that an ETC of area 54 m2, tilt angle of 25° and storage tank volume of 2.1 m3 provides 80% of air-conditioning demand in a house located in Kuwait.

  19. Participation in multilateral effort to develop high performance integrated CPC evacuated collectors

    Science.gov (United States)

    Winston, R.; Ogallagher, J. J.

    1992-05-01

    The University of Chicago Solar Energy Group has had a continuing program and commitment to develop an advanced evacuated solar collector integrating nonimaging concentration into its design. During the period from 1985-1987, some of our efforts were directed toward designing and prototyping a manufacturable version of an Integrated Compound Parabolic Concentrator (ICPC) evacuated collector tube as part of an international cooperative effort involving six organizations in four different countries. This 'multilateral' project made considerable progress towards a commercially practical collector. One of two basic designs considered employed a heat pipe and an internal metal reflector CPC. We fabricated and tested two large diameter (125 mm) borosilicate glass collector tubes to explore this concept. The other design also used a large diameter (125 mm) glass tube but with a specially configured internal shaped mirror CPC coupled to a U-tube absorber. Performance projections in a variety of systems applications using the computer design tools developed by the International Energy Agency (IEA) task on evacuated collectors were used to optimize the optical and thermal design. The long-term goal of this work continues to be the development of a high efficiency, low cost solar collector to supply solar thermal energy at temperatures up to 250 C. Some experience and perspectives based on our work are presented and reviewed. Despite substantial progress, the stability of research support and the market for commercial solar thermal collectors were such that the project could not be continued. A cooperative path involving university, government, and industrial collaboration remains the most attractive near term option for developing a commercial ICPC.

  20. Estimation and optimization of thermal performance of evacuated tube solar collector system

    Science.gov (United States)

    Dikmen, Erkan; Ayaz, Mahir; Ezen, H. Hüseyin; Küçüksille, Ecir U.; Şahin, Arzu Şencan

    2014-05-01

    In this study, artificial neural networks (ANNs) and adaptive neuro-fuzzy (ANFIS) in order to predict the thermal performance of evacuated tube solar collector system have been used. The experimental data for the training and testing of the networks were used. The results of ANN are compared with ANFIS in which the same data sets are used. The R2-value for the thermal performance values of collector is 0.811914 which can be considered as satisfactory. The results obtained when unknown data were presented to the networks are satisfactory and indicate that the proposed method can successfully be used for the prediction of the thermal performance of evacuated tube solar collectors. In addition, new formulations obtained from ANN are presented for the calculation of the thermal performance. The advantages of this approaches compared to the conventional methods are speed, simplicity, and the capacity of the network to learn from examples. In addition, genetic algorithm (GA) was used to maximize the thermal performance of the system. The optimum working conditions of the system were determined by the GA.

  1. Low-cost evacuated-tube solar collector appendices. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Beecher, D.T.

    1980-05-31

    A low cost solar heat energy collector module and array has been designed using the evacuated tube, selective absorber, air cooled concept. Glass tubing as used in fluorescent lamps with automatic sealing methods is a key feature of the evacuated tube design. A molded fiber glass concentrating reflector panel and sheet metal header assembly are proposed. Major design problems involved included the cost of materials and labor, thermal expansion and distortion problems, high stagnation and operating temperatures, isolation, thermal efficiency, sealing, joining, air pressure drop, and weight of the preassembled module. A cost of less than $5 per active square foot of collecting surface has been estimated for materials and labor of the module and its mounting frame.

  2. SOLAR REFRIGERATING UNIT WITH AN ADSORPTION REACTOR AND EVACUATED TUBE COLLECTORS

    Directory of Open Access Journals (Sweden)

    M.E. Vieira

    1997-09-01

    Full Text Available This work presents the principles of operation of a solar refrigerator with the following basic components: a reactor, a set of evacuated tube solar collectors, a condenser, a heat exchanger, and an evaporator. During the heating phase, solar radiation is collected and transferred to the reactor for desorption by a vapor thermal siphon loop. During the cooling phase, heat from the reactor is released to the ambient by a second water vapor loop. Ambient data collected daily during a period of 18 years were divided into hourly values and used to simulate the temperatures of the reactor, which uses salt impregnated with graphite and ammonia, during the adsorption / desorption processes. The results show that the refrigerator operates well in Fortaleza and that better results are expected for the countryside of the state of Ceara. It is concluded that only a high efficiency collector set can be used in the system

  3. Optimized reflectors for non-tracking solar collectors with tubular absorbers

    Energy Technology Data Exchange (ETDEWEB)

    Muschaweck, Julius [Optics and Energy Consulting, Munich (Germany); Spirkl, Wolfgang [Ludwig-Maximilians Univ., Sektion Physik, Munich (Germany); Timinger, Andreas [Optics and Energy Consulting, Munich (Germany); ZAE Bayern, Solar Thermal and Biomass Dept., Munich (Germany); Benz, Nikolaus; Doerfler, Michael; Gut, Martin [ZAE Bayern, Solar Thermal and Biomass Dept., Munich (Germany); Kose, Erwin [microtherm Energietecjnik GmbH, Lods, 25 (France)

    2000-07-01

    We present an approach to find optimal reflector shapes for non-tracking solar collectors under practical constraints. We focus on cylindrical absorbers and reflectors with translational symmetry. Under idealised circumstances, edge ray reflectors are well known to be optimal. However, it is not clear how optimal reflectors should be shaped in order to obtain maximum utilisable energy for given operating temperatures under practical constraints like reflectivity less than unity, real radiation data, size limits, and gaps between the reflector and the absorber. For a prototype collector with a symmetric edge ray reflector and a tubular absorber, we derive from calorimetric measurements under outdoor conditions the optical efficiency as a function of the incidence angle. Using numerical optimisation and raytracing, we compare truncated symmetric edge ray reflectors, truncated asymmetric edge ray reflectors and free forms parametrized by Bezier splines. We find that asymmetric edge ray reflectors are optimal. For reasonable operating conditions, truncated asymmetric edge ray reflectors allow much better land use and easily adapt to a large range of roof tilt angles with marginal changes in collector construction. Except near the equator, they should increase the yearly utilisable energy per absorber tube by several percent as compared to the prototype collector with symmetric reflectors. (Author)

  4. Feasibility of active solar water heating systems with evacuated tube collector at different operational water temperatures

    International Nuclear Information System (INIS)

    Mazarrón, Fernando R.; Porras-Prieto, Carlos Javier; García, José Luis; Benavente, Rosa María

    2016-01-01

    Highlights: • Analysis of the feasibility of an active solar water-heating system. • Profitability decreases as the required water temperature increases. • The number of collectors that maximizes profitability depends on the required temperature. • Investment in a properly sized system generates savings between 23% and 15%. • Fuel consumption can be reduced by 70%. - Abstract: With rapid advancements in society, higher water temperatures are needed in a number of applications. The demand for hot water presents a great variability with water required at different temperatures. In this study, the design, installation, and evaluation of a solar water heating system with evacuated tube collector and active circulation has been carried out. The main objective is to analyze how the required tank water temperature affects the useful energy that the system is capable of delivering, and consequently its profitability. The results show how the energy that is collected and delivered to the tank decreases with increasing the required temperature due to a lower performance of the collector and losses in the pipes. The annual system efficiency reaches average values of 66%, 64%, 61%, 56%, and 55% for required temperatures of 40 °C, 50 °C, 60 °C, 70 °C, and 80 °C. As a result, profitability decreases as temperature increases. The useful energy, and therefore the profitability, will decrease if the demand is not distributed throughout the day or focused on the end of the day. The system’s profitability was determined in two cases: considering maximum profitability of the system, assuming 100% utilization of useful energy (scenario 1); assuming a particular demand, considering that on many days all the useful energy the system can supply is not used (scenario 2). The analysis shows that through proper sizing of the system, optimizing the number of solar collectors, the investment in the solar system can be profitable with similar profitability values in the two

  5. PERFORMANCE OF EVACUATED TUBE SOLAR COLLECTOR USING WATER-BASED TITANIUM OXIDE NANOFLUID

    Directory of Open Access Journals (Sweden)

    M. Mahendran

    2012-12-01

    Full Text Available Experiments are undertaken to determine the efficiency of an evacuated tube solar collector using water-based Titanium Oxide (TiO2 nanofluid at the Pekan Campus (3˚32’ N, 103˚25’ E, Faculty of Mechanical Engineering, University Malaysia Pahang, for the conversion of solar thermal energy. Malaysia lies in the equatorial zone with an average daily solar insolation of more than 900 W/m², which can reach a maximum of 1200 W/m² for most of the year. Traditionally water is pumped through the collector at an optimum flow rate, for the extraction of solar thermal energy. If the outlet temperature of the water is high, further circulation of the water through the collector is useless. This is due to the low thermal conductivity of water of 0.6 W/m.K compared to metals which is many orders higher. Hence it is necessary to reduce the surface temperature either by pumping water at a higher flow rate or by enhancing the fluid’s properties by the dispersion of nanoparticles. Pumping water at higher flow rates is not advantageous as the overall efficiency of the system is lowered. Liquids in which nanosized particles of metal or their oxides are dispersed in a base liquid such as water are known as 'Nanofluids'. This results in higher values of thermal conductivity compared to the base liquid. The thermal conductivity increases with the concentration and temperature of the nanofluid. The increase in thermal conductivity with temperature is advantageous for application in collectors as the solar insolation varies throughout the day, with a minimum in the morning reaching a maximum at 2.00p.m and reducing thereafter. The efficiency of the collector estimated using a TiO2 nanofluid of 0.3% concentration is about 0.73, compared to water which is about 0.58. The efficiency is enhanced by 16.7% maximum with 30–50nm sized TiO2 nanoparticles dispersed in the water, compared to the system working solely with water. The flow rate is fixed at 2.7 liters per

  6. Standardized performance tests of collectors of solar thermal energy: An evacuated flatplate copper collector with a serpentine flow distribution

    Science.gov (United States)

    Johnson, S. M.

    1976-01-01

    Basic test results are given for a flat plate solar collector whose performance was determined in the NASA-Lewis solar simulator. The collector was tested over ranges of inlet temperatures, fluxes and one coolant flow rate. Collector efficiency is correlated in terms of inlet temperature and flux level.

  7. Experimental investigation and thermodynamic performance analysis of a solar dryer using an evacuated-tube air collector

    International Nuclear Information System (INIS)

    Lamnatou, Chr.; Papanicolaou, E.; Belessiotis, V.; Kyriakis, N.

    2012-01-01

    Highlights: ► We evaluate an evacuated-tube solar air collector and use it to develop a novel dryer. ► Apple, carrot and apricot thin-layer drying experiments are conducted. ► Best overall fitting among several available thin-layer drying models is pursued. ► Thermodynamic analysis yields optimal collector area, energy utilization/exergy loss. ► The proposed dryer has a capacity for drying larger quantities of products. -- Abstract: The present work presents a thermodynamic performance analysis of a solar dryer with an evacuated-tube collector. Drying experiments for apples, carrots and apricots were conducted, after a preliminary stage of the investigation which included measurements for the determination of the collector efficiency. These results showed that the warm outlet air of the collector attains temperature levels suitable for drying of agricultural products without the need of preheating. Thus, the present collector was used as the heat source for a drying chamber in the frame of the development of a novel, convective, indirect solar dryer; given the fact that in the literature there are only a few studies about this type of collectors in conjunction with solar drying applications. Thin-layer drying models were fitted to the experimental drying curves, including the recent model of Diamante et al. which showed good correlation coefficients for all the tested products. Drying parameters such as moisture ratio and drying rates were calculated. Furthermore, an energetic/exergetic analysis of the dryer was also conducted and performance coefficients such as pick-up and exergy efficiencies, energy utilization ratio, exergy losses were determined for several configurations such as single and double-trays and several drying air velocities. On the other hand, an optimal collector surface area study was conducted, based on laws for minimum entropy generation. Design parameters such as optimum collector area were determined based on the minimum entropy

  8. Theoretical model of an evacuated tube heat pipe solar collector integrated with phase change material

    International Nuclear Information System (INIS)

    Naghavi, M.S.; Ong, K.S.; Badruddin, I.A.; Mehrali, M.; Silakhori, M.; Metselaar, H.S.C.

    2015-01-01

    The purpose of this paper is to model theoretically a solar hot water system consisting of an array of ETHPSC (evacuated tube heat pipe solar collectors) connected to a common manifold filled with phase change material and acting as a LHTES (latent heat thermal energy storage) tank. Solar energy incident on the ETHPSC is collected and stored in the LHTES tank. The stored heat is then transferred to the domestic hot water supply via a finned heat exchanger pipe placed inside the tank. A combination of mathematical algorithms is used to model a complete process of the heat absorption, storage and release modes of the proposed system. The results show that for a large range of flow rates, the thermal performance of the ETHPSC-LHTES system is higher than that of a similar system without latent heat storage. Furthermore, the analysis shows that the efficiency of the introduced system is less sensitive to the draw off water flowrate than a conventional system. Analysis indicates that this system could be applicable as a complementary part to conventional ETHPSC systems to be able to produce hot water at night time or at times with weak radiation. - Highlights: • The ETHPSC is integrated with PCM at manifold side for night hot water demands. • The thermal performance of the ETHPSC-PCM is often higher than the baseline model. • The efficiency of the proposed model is stable for different flow rates. • Using PCM as thermal storage increases reliability on the performance of the system.

  9. A Study on Thermal Performance of a Novel All-Glass Evacuated Tube Solar Collector Manifold Header with an Inserted Tube

    Directory of Open Access Journals (Sweden)

    Jichun Yang

    2015-01-01

    Full Text Available A novel all-glass evacuated tube collector manifold header with an inserted tube is proposed in this paper which makes water in all-glass evacuated solar collector tube be forced circulated to improve the performance of solar collector. And a dynamic numerical model was presented for the novel all-glass evacuated tube collector manifold header water heater system. Also, a test rig was built for model validation and comparison with traditional all-glass evacuated tube collector. The experiment results show that the efficiency of solar water heater with a novel collector manifold header is higher than traditional all-glass evacuated tube collector by about 5% and the heat transfer model of water heater system is valid. Based on the model, the relationship between the average temperature of water tank and inserted tube diameter (water mass flow has been studied. The results show that the optimized diameter of inserted tube is 32 mm for the inner glass with the diameter of 47 mm and the water flow mass should be less than 1.6 Kg/s.

  10. Exergy Analyses of Fabricated Compound Parabolic Solar Collector with Evacuated Tubes at Different Operating Conditions: Indore (India)

    Science.gov (United States)

    Geete, Ankur; Dubey, Akash; Sharma, Ankush; Dubey, Anshul

    2018-05-01

    In this research work, compound parabolic solar collector (CPC) with evacuated tubes is fabricated. Main benefit of CPC is that there is no requirement of solar tracking system. With fabricated CPC; outlet temperatures of flowing fluid, instantaneous efficiencies, useful heat gain rates and inlet exergies (with and without considering Sun's cone angle) are experimentally found. Observations are taken at different time intervals (1200, 1230, 1300, 1330 and 1400 h), mass flow rates (1.15, 0.78, 0.76, 0.86 and 0.89 g/s), ambient temperatures and with various dimensions of solar collector. This research work is concluded as; maximum instantaneous efficiency is 69.87% which was obtained with 0.76 g/s flow rate of water at 1300 h and 42°C is the maximum temperature difference which was also found at same time. Maximum inlet exergies are 139.733 and 139.532 kW with and without considering Sun's cone angle at 1300 h, respectively. Best thermal performance from the fabricated CPC with evacuated tubes is found at 1300 h. Maximum inlet exergy is 141.365 kW which was found at 1300 h with 0.31 m aperture width and 1.72 m absorber pipe length.

  11. Simulation of Evacuated Tube Collector and Storage of Hybrid Air-conditioning System

    Directory of Open Access Journals (Sweden)

    Mustafa Ahmed Abdulhussain

    2018-02-01

    Full Text Available The CFD transient simulation of superheating the refrigerant R410 through the heat exchange with the evacuated tube water heating system of the hybrid split air conditioner that is subjected to solar radiation of constant intensity with the contribution of fan accelerated air is performed by the ANSYS-CFX code. The comparison with experimental work showed a minimum percentage error 8% of the predicted refrigerant evaporative heat transfer with storage tank horizontal tubing. In addition, the results denoted high absorption rate for the evacuated tubes, reducing highly reversed heat transmission for the circulated water. 

  12. Design of Pumping Station for the Solar Evacuated Collector Tubes%太阳能真空集热管排气台的设计

    Institute of Scientific and Technical Information of China (English)

    任家生; 毛福明; 赵正中; 刘兆斌

    2001-01-01

    In this paper, the design requirements and constructure speciality of pumping station for the solar evacuated collector tubes are reported.%本文介绍了太阳能真空集热管排气台的设计要求与结构特点.

  13. Performance study on evacuated tube solar collector using therminol D-12 as heat transfer fluid coupled with parabolic trough

    International Nuclear Information System (INIS)

    Selvakumar, P.; Somasundaram, P.; Thangavel, P.

    2014-01-01

    Highlights: • Instant hot water at temperatures between 40 °C and 68 °C in the low solar radiation range of 240–540 W/m 2 . • Usage of therminol D-12 and parabolic trough in low temperature application. • Stability of thermal and flow properties of therminol D-12 are studied. - Abstract: Fossil fuels and electrical energy are widely used for instant hot water generation in rural and urban areas. Also, conventional solar water heaters do not support instant hot water generation because of various problems. A new system with evacuated tube collector using synthetic oil as heat transfer fluid coupled with parabolic trough is developed and studied experimentally for instant hot water generation in the presence of low solar irradiance. Among the different grades of therminol, therminol D-12 is chosen for the study because of its thermal stability. Parabolic trough is coupled to evacuated tube to enhance the flow as well as heating characteristics of therminol. Heating efficiency and temperature characteristics are determined for the newly developed system under low solar irradiance conditions. Instant hot water can be produced by the new system at a temperature of 60 °C in the presence of low solar radiation. This newly developed system has the ability to check the fossil fuel consumption and electrical energy consumption for instant hot water generation in household applications. The stability of the heat transfer fluid is also ensured by repeated experiments

  14. Ni/Ni-YSZ current collector/anode dual layer hollow fibers for micro-tubular solid oxide fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Kanawka, K.; Othman, M.H.D.; Droushiotis, N.; Wu, Z.; Kelsall, G.; Li, K. [Department of Chemical Engineering and Chemical Technology, Imperial College London, London SW7 2AZ (United Kingdom)

    2011-10-15

    A co-extrusion technique was employed to fabricate a novel dual layer NiO/NiO-YSZ hollow fiber (HF) precursor which was then co-sintered at 1,400 C and reduced at 700 C to form, respectively, a meshed porous inner Ni current collector and outer Ni-YSZ anode layers for SOFC applications. The inner thin and highly porous ''mesh-like'' pure Ni layer of approximately 50 {mu}m in thickness functions as a current collector in micro-tubular solid oxide fuel cell (SOFC), aiming at highly efficient current collection with low fuel diffusion resistance, while the thicker outer Ni-YSZ layer of 260 {mu}m acts as an anode, providing also major mechanical strength to the dual-layer HF. Achieved morphology consisted of short finger-like voids originating from the inner lumen of the HF, and a sponge-like structure filling most of the Ni-YSZ anode layer, which is considered to be suitable macrostructure for anode SOFC system. The electrical conductivity of the meshed porous inner Ni layer is measured to be 77.5 x 10{sup 5} S m{sup -1}. This result is significantly higher than previous reported results on single layer Ni-YSZ HFs, which performs not only as a catalyst for the oxidation reaction, but also as a current collector. These results highlight the advantages of this novel dual-layer HF design as a new and highly efficient way of collecting current from the lumen of micro-tubular SOFC. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  15. The sizes of Flat Plate and Evacuated Tube Collectors with Heat Pipe area as a function of the share of solar system in the heat demand

    Directory of Open Access Journals (Sweden)

    Olek Małgorzata

    2016-01-01

    Full Text Available The popularity of solar collectors in Poland is still increasing. The correct location of the collectors and a relatively high density of solar radiation allow delivering heat even in spite of relatively low ambient temperature. Moreover, solar systems used for heating domestic heat water (DHW in summer allow nearly complete elimination of conventional energy sources (e.g. gas, coal. That is why more and more house owners in Poland decide to install solar system installations. In Poland the most common types of solar collectors are flat plate collectors (FPC and evacuated tube collectors with heat pipe (ETCHP; both were selected for the analysis. The heat demand related to the preparation of hot water, connected with the size of solar collectors’ area, has been determined. The analysis includes FPC and ETCHP and heat demand of less than 10 000 kWh/year. Simulations were performed with the Matlab software and using data from a typical meteorological year (TMY. In addition, a 126–year period of measurements of insolation for Krakow has been taken into account. The HDKR model (Hay, Davis, Klucher, Reindl was used for the calculation of solar radiation on the absorber surface. The monthly medium temperature of the absorber depends on the amount of solar system heat and on the heat demand. All the previously mentioned data were used to determine solar efficiency. Due to the fact that solar efficiency and solar system heat are connected, the calculations were made with the use of an iterative method. Additionally, the upper limit for monthly useful solar system heat is resulted from the heat demand and thus the authors prepared a model of statistical solar system heat deviations based on the Monte Carlo method. It has been found that an increase in the useful solar system heat in reference to the heat demand is associated with more than proportional increase in the sizes of the analyzed surfaces of solar collector types.

  16. Design and simulation of a prototype of a small-scale solar CHP system based on evacuated flat-plate solar collectors and Organic Rankine Cycle

    International Nuclear Information System (INIS)

    Calise, Francesco; D’Accadia, Massimo Dentice; Vicidomini, Maria; Scarpellino, Marco

    2015-01-01

    Highlights: • A novel small scale solar power plant was designed and simulated. • The system is based on evacuated solar thermal collectors and an ORC system. • An average electric efficiency of 10% was found for the ORC. • The efficiency of solar collectors was found to be high in summer (>50%). • Pay-back periods lower than 5 years were estimated, in case of public funding. - Abstract: This paper presents a dynamic simulation model of a novel prototype of a 6 kW e solar power plant. The system is based on the coupling of innovative solar thermal collectors with a small Organic Rankine Cycle (ORC), simultaneously producing electric energy and low temperature heat. The novelty of the proposed system lies in the solar collector field, which is based on stationary evacuated flat-plate solar thermal collectors capable to achieve the operating temperatures typical of the concentrating solar thermal collectors. The solar field consists of about 73.5 m 2 of flat-plate evacuated solar collectors, heating a diathermic oil up to a maximum temperature of 230 °C. A diathermic oil storage tank is employed in order to mitigate the fluctuations due to the variability of solar energy availability. The hot diathermic oil exiting from the tank passes through an auxiliary gas-fired burner which provides eventual additional thermal energy. The inlet temperature of the diathermic oil entering the ORC system varies as a function of the availability of solar energy, also determining an oscillating response of the ORC. The ORC was simulated in Engineering Equation Solver (EES), using zero-dimensional energy and mass balances. The ORC model was subsequently implemented in a more general TRNSYS model, including all the remaining components of the system. The model was used to evaluate the energy and economic performance of the solar CHP system under analysis, in different climatic conditions. The results show that the efficiency of the ORC does not significantly vary during the

  17. Collecting performance of an evacuated tubular solar high-temperature air heater with concentric tube heat exchanger

    International Nuclear Information System (INIS)

    Wang, Ping-Yang; Li, Shuang-Fei; Liu, Zhen-Hua

    2015-01-01

    Highlights: • A novel evacuated tube solar high temperature air heater is designed. • The solar air heater system consists of 30 linked collecting units. • Every unit consisted of a evacuated tube, a simplified CPC and concentric tube. • The flow air is heated over temperature of 200 °C. - Abstract: A set of evacuated tube solar high temperature air heaters with simplified CPC (compound parabolic concentrator) and concentric tube heat exchanger is designed to provide flow air with a temperature of 150–230 °C for industrial production. The solar air heater system consists of 30 linked collecting units. Each unit includes a simplified CPC and an all-glass evacuated tube absorber with a concentric copper tube heat exchanger installed inside. A stainless steel mesh layer with high thermal conductivity is filled between the evacuated tube and the concentric copper tube. Air passes through each collecting unit, and its temperature increases progressively. An experimental investigation of the thermal performance of the air heater is performed, and the experimental results demonstrate the presented high-temperature solar air heater has excellent collecting performance and large output power, even in the winter. The measured thermal efficiency corresponding to the air temperature of 70 °C reaches 0.52. With the increase of air temperature, thermal efficiency reaches 0.35 at an air temperature of 150 °C, and 0.21 at an air temperature of 220 °C.

  18. High temperature collecting performance of a new all-glass evacuated tubular solar air heater with U-shaped tube heat exchanger

    International Nuclear Information System (INIS)

    Wang, Pin-Yang; Guan, Hong-Yang; Liu, Zhen-Hua; Wang, Guo-San; Zhao, Feng; Xiao, Hong-Sheng

    2014-01-01

    Highlights: • A novel solar air heater with simplified CPC and U-type heat exchanger is designed and tested. • The system is made up of 10 linked collecting panels. • Simplified CPC has a much lower cost at the expense of slight efficiency loss. • The air heater can propose the heated air exceeding 200 °C with great air flow rate. - Abstract: Experiment and simulation are conducted on a new-type all-glass evacuated tubular solar air heater with simplified compound parabolic concentrator (CPC). The system is made up of 10 linked collecting panels and each panel includes a simplified CPC and an all-glass evacuated tube with a U-shaped copper tube heat exchanger installed inside. Air is gradually heated when passing through each U-shaped copper tube. The heat transfer model of the solar air heater is established and the outlet air temperature, the heat power and heat efficiency are calculated. Calculated and experimental results show that the present experimental system can provide the heated air exceeding 200 °C. The whole system has an outstanding high-temperature collecting performance and the present heat transfer model can meet the general requirements of engineering calculations

  19. A thermal-optical analysis comparison between symmetric tubular absorber compound parabolic concentrating solar collector with and without envelope

    International Nuclear Information System (INIS)

    Tchinda, R.

    2005-11-01

    Equations describing the heat transfer in symmetric, compound parabolic concentrating solar collectors (CPCs) with and without envelope have been established. The model takes into account the non linear behavior of these two systems. A theoretical numerical model has been developed to outline the effect of the envelope on the thermal and optical performance of CPCs. The effects of the flow rate, the plate length, the selective coating, etc. are studied. The over-all thermal loss coefficient and the enclosure absorption factor for both types are defined. It is found that the efficient configuration has an envelope. Theoretical computed values are in good agreement with the experimental values published in the literature. (author)

  20. Influence of the receiver’s back surface radiative characteristics on the performance of a heat-pipe evacuated-tube solar collector

    International Nuclear Information System (INIS)

    Zheng, Hongfei; Xiong, Jianying; Su, Yuehong; Zhang, Haiyin

    2014-01-01

    Highlights: • A model for describing the heat transfer characteristics of the ETSC is derived. • A method by performing roughness treatment is proposed to change the emissivity. • Increasing the receiver’s back surface emissivity can greatly affect the heat loss. • Real weather test verifies the proposed method in controlling overheat phenomenon. - Abstract: The receiver’s back surface radiative characteristics of a heat-pipe evacuated-tube solar collector (ETSC) may have a significant influence on its performance. This influence is generally related to the back surface emissivity and temperature; however it has been not studied previously. This paper firstly presents a heat transfer model for the ETSC, which is then derived to characterize the relationship between the heat loss and the back surface emissivity of the ETSC. A steady state experiment has been also performed to measure the heat loss of ETSC with different back surface emissivity values. The experimental results indicate that the heat loss of the ETSC increases with the increase of the back surface emissivity, but the rate of increase differs for different operation temperatures. When the back surface emissivity increases from 0.03 to 0.12, the heat loss of ETSC only increases by 31% when the operation temperature is below 100 °C, but the heat loss will increase to 96% when the operation temperature is over 200 °C. This means that the change of back surface emissivity can significantly affect the performance of the ETSC at higher temperature but affect little at lower temperature. Based on this, a novel method by performing roughness treatment on the receiver’s back surface is proposed to solve the overheating problem of ETSC in summer. Two solar water heaters including 6 ETSCs with standard and roughness-treated tubes were tested under real weather condition. Experiment reveals that when the water temperature in tank is below 60 °C, the two solar water heaters own similar temperature

  1. Experimental analysis of solar thermal integrated MD system for cogeneration of drinking water and hot water for single family villa in dubai using flat plate and evacuated tube solar collectors

    DEFF Research Database (Denmark)

    Asim, Muhammad; Imran, Muhammad; Leung, Michael K.H.

    2017-01-01

    This paper presents the experimental analysis performed on solar thermal integrated membrane distillation (MD) system using flat plate and evacuated tube collectors. The system will be utilized for cogeneration of drinking water and domestic hot water for single family in Dubai comprising of four...... to five members. Experiments have been performed in Ras Al Khaimah Research and Innovation Centre (RAKRIC) facility. The experimental setup has been installed to achieve the required production of 15–25 L/d of drinking water and 250 L/d of hot water for domestic purposes. Experiments have been performed...

  2. Side-by-side comparisons of evacuated compound parabolic concentrator and flat plate solar collector systems at temperatures of 90 to 100C

    Science.gov (United States)

    Allen, J. W.; Schertz, W. W.; Wantroba, A. S.

    1987-03-01

    This collector system study is an extension of a previous system study in which Argonne National Laboratory (ANL) compared the performance of three solar energy systems operated side by side for over a year. In the present system study, four solar energy systems were operated side by side for part of a year. Two of the collector systems used commercially available compound parabolic concentrator (CPC) collectors, one used a commercially available flat plate collector, and one used an experimental CPC collector built by The University of Chicago. The collectors were mounted in fixed positions; they did not track the Sun, and their tilt angles were not seasonally adjusted. All of the collector arrays faced south and were tilted at 42 deg with respect to the horizon (to match the 42 deg N latitude at ANL). All four collector systems started each day with their storage temperatures at 90 C. During the day, each system was operated by its own solar controller. At the end of the day, the tanks were mixed and the temperature changes in the tanks were measured. The change in storage energy was calculated from the temperature change, the heat capacity of the storage system, and the pump energy.

  3. New collectors from all over the world

    Energy Technology Data Exchange (ETDEWEB)

    Augsten, Eva

    2008-07-01

    Flat-plate collectors are fashionable, even among customers in Shanghai, although China is considered the land of evacuated tubes. Elsewhere, fashion is also a consideration, which partly explains the switch from fin collectors to full-surface collectors. Sun and Wind Energy has put together a list of new collectors from various countries. (orig.)

  4. Dynamic testing of solar collectors under special consideration of the correction of the inclination angle and reduction of the test duration; Dynamische Pruefung von Sonnenkollektoren unter besonderer Beruecksichtigung der Einfallswinkelkorrektur und der Reduzierung der Pruefdauer

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Stephan

    2011-07-01

    Solar thermal systems are gaining more and more market shares. At the beginning of the last decade only systems for swimming pool heating and domestic hot water heating were available on the market. Today the system variety includes additionally solar thermal systems for space heating, solar thermal cooling, process heat and solar thermal power plants. Independent of the purpose of the solar thermal system, it is always the collector that converts the solar irradiance into heat and is thus the most important component within a solar thermal system. The high number of applications results also in a large variety of different collector concepts. The differences between flat plate collectors, evacuated tubular collectors (with or without heat pipes). CPC collectors, parabolic trough collectors. Fresnel collectors and others is not limited to geometry and working principles but include as well the thermal performance, especially when the thermal behaviour under different angles of incidence and fractions of diffuse irradiance is taking into account. For the test of solar thermal collectors and for the optimisation of solar thermal systems a mathematical model is necessary to describe the thermal performance of the solar collector. Thus this thesis is dealing with the mathematic modelling and the experimental testing of solar thermal collectors. Based on already existing procedures a numerical model and a new procedure for the test of thermal collectors is introduced. The numerical model enables the description of the thermal behaviour for most collectors available on the market. The numerical model and the test procedure were developed paying special attention to the incidence angle modifier and the reduction of testing time. As basis for the general numerical model and the test procedure part one of the thesis describes and discusses the parameters needed to characterise the thermal performance of solar thermal collectors. It is shown that some of the influencing

  5. Testing of PCM Heat Storage Modules with Solar Collectors as Heat Source

    DEFF Research Database (Denmark)

    Englmair, Gerald; Dannemand, Mark; Johansen, Jakob Berg

    2016-01-01

    A latent heat storage based on the phase change material Sodium Acetate Trihydrate (SAT) has been tested as part of a demonstration system. The full heat storage consisted of 4 individual modules each containing about 200 kg of sodium acetate trihydrate with different additives. The aim...... was to actively utilize the ability of the material to supercool to obtain long storage periods. The modules were charged with solar heat supplied by 22.4 m2 evacuated tubular collectors. The investigation showed that it was possible to fully charge one module within a period of 270 minutes with clear skies...

  6. Evacuation exercise

    CERN Multimedia

    AUTHOR|(CDS)2094367

    2017-01-01

    In the event of an emergency, it is important that staff and visitors are evacuated safely and efficiently. Hence CERN organises regularly emergency response and evacuation exercise (also known as an ‘evacuation drill’) in different buildings across the sites.

  7. Effect of Installation of Solar Collector on Performance of Balcony Split Type Solar Water Heaters

    Directory of Open Access Journals (Sweden)

    Xu Ji

    2015-01-01

    Full Text Available The influences of surface orientation and slope of solar collectors on solar radiation collection of balcony split type solar water heaters for six cities in China were analyzed by employing software TRNSYS. The surface azimuth had greater effect on solar radiation collection in high latitude regions. For deviation of the surface slope angle within ±20° around the optimized angle, the variation of the total annual collecting solar radiation was less than 5%. However, with deviation of 70° to 90°, the variation was up to 20%. The effects of water cycle mode, reverse slope placement of solar collector, and water tank installation height on system efficiency were experimentally studied. The thermal efficiencies of solar water heater with single row horizontal arrangement all-glass evacuated tubular collector were higher than those with vertical arrangement at the fixed surface slope angle of 90°. Compared with solar water heaters with flat-plate collector under natural circulation, the system thermal efficiency was raised up to 63% under forced circulation. For collector at reverse slope placement, the temperature-based water stratification in water tank deteriorated, and thus the thermal efficiency became low. For improving the system efficiency, an appropriate installation height of the water tank was suggested.

  8. Tubular combustion

    CERN Document Server

    Ishizuka, Satoru

    2014-01-01

    Tubular combustors are cylindrical tubes where flame ignition and propagation occur in a spatially confined, highly controlled environment, in a nearly flat, elongated geometry. This allows for some unique advantages where extremely even heat dispersion is required over a large surface while still maintaining fuel efficiency. Tubular combustors also allow for easy flexibility in type of fuel source, allowing for quick changeover to meet various needs and changing fuel pricing. This new addition to the MP sustainable energy series will provide the most up-to-date research on tubular combustion--some of it only now coming out of private proprietary protection. Plentiful examples of current applications along with a good explanation of background theory will offer readers an invaluable guide on this promising energy technology. Highlights include: * An introduction to the theory of tubular flames * The "how to" of maintaining stability of tubular flames through continuous combustion * Examples of both small-scal...

  9. Tube collector with integrated tracking parabolic concentrator

    Energy Technology Data Exchange (ETDEWEB)

    Grass, C.; Benz, N.; Hacker, Z.; Timinger, A. [ZAE Bayern, Bavarian Centre for Applied Energy Research, Muenchen (Germany)

    2000-07-01

    Low concentrating CPC collectors usually do not track the sun and are mounted in east-west direction with a latitude dependent slope angle. They are most suitable for maximum working temperatures up to 200 250 deg. C. We present a novel evacuated tube-collector with a trough-like concentrating mirror. Single-axis tracking of the mirror is realized with a magnetic mechanism. The mirror is mounted inside the evacuated tube and hence protected from environmental influences. One axis tracking in combination with a small acceptance angle allows for higher concentration as compared to non-tracking concentrating collectors. Ray-tracing analysis shows a half acceptance angle of about 5 deg. at a geometrical concentration ratio of 3.2. The losses of evacuated tube collectors are dominated by the radiation losses of the absorber. Hence, reducing the absorber size can lead to higher efficiencies at high operating temperature levels. With the presented collector we aim for operating temperatures up to 400 deg. C. At temperatures of 300 deg. C we expect efficiencies of 65 %. This allows for application in industrial process heat generation, high efficient solar cooling and power generation. A first prototype was tested at the ZAE Bayern. The optical efficiency was measured to be 75 %. (au)

  10. Performance of solar collectors under low temperature conditions

    DEFF Research Database (Denmark)

    Bunea, Mircea; Eicher, Sara; Hildbrand, Catherine

    The performance of four solar thermal collectors (flat plate, evacuated tube, unglazed with rear insulation and unglazed without rear insulation) was experimentally measured and simulated for temperatures below ambient. The influence of several parameters (e.g. collector inlet temperature, air...... evaluated and results compared to experimental measurements. A mathematical model is also under development to include, in addition to the condensation phenomena, the frost, the rain and the long-wave radiation gains/losses on the rear of the solar collector. While the potential gain from rain was estimated...... to be around 2%, frost heat gains were measured to be up to 40% per day, under specific conditions. Overall, results have shown that unglazed collectors are more efficient than flat plate or evacuated tube collectors at low operation temperatures or for night conditions, making them more suitable for heat pump...

  11. Dust collector

    Energy Technology Data Exchange (ETDEWEB)

    Sahourin, H.

    1988-03-22

    This invention relates to a dust collector or filter which may be used for large volume cleaning air for gases or for separating out industrial byproducts such as wood chips, sawdust, and shavings. It relies on filtration or separation using only a uniquely configured medium. A primary, but not exclusive, purpose of the invention is to enable very large throughput, capable of separating or filtering of gases containing up to three or more tons of byproduct with a minimum pressure-drop across the device. No preliminary cycloning, to remove major particulates is necessary. The collector generally comprises a continuous and integral filter medium which is suspended from a plurality of downwardly extending frames forming a series of separate elements having a triangular cross-section, each element being relatively wide at the top and narrow at the bottom to define, between adjacent elements, a divergent collecting space which is wide at the bottom. 11 figs.

  12. Magnetic collectors

    International Nuclear Information System (INIS)

    Frew, J.D.

    1980-01-01

    A collector for use in a magnetic separator is formed by isostatically pressing a metal which is resistant to attack by acid about ferromagnetic bodies whereby to encase the bodies in the metal. In one arrangement, as shown, the bodies are encapsulated between inner and outer cylinders. In other arrangements the encapsulating metal is in the form of a tube or planar sheets. The bodies are of Fe or an oxide thereof and the acid-resistant metal parts may be of stainless steel, Au, Pt, Pa or an alloy. The magnetic separator is intended for use in removing particles from liquids during the reprocessing of nuclear fuel materials. (author)

  13. Hurricane Evacuation Routes

    Data.gov (United States)

    Department of Homeland Security — Hurricane Evacuation Routes in the United States A hurricane evacuation route is a designated route used to direct traffic inland in case of a hurricane threat. This...

  14. Evacuated aerogel glazings

    DEFF Research Database (Denmark)

    Schultz, Jørgen Munthe; Jensen, Karsten Ingerslev

    2008-01-01

    This paper describes the main characteristics of monolithic silica aerogel and its application in evacuated superinsulating aerogel glazing including the evacuation and assembling process. Furthermore, the energetic benefit of aerogel glazing is quantified. In evacuated aerogel glazing the space ......) combined with a solar energy transmittance above 0.75.......This paper describes the main characteristics of monolithic silica aerogel and its application in evacuated superinsulating aerogel glazing including the evacuation and assembling process. Furthermore, the energetic benefit of aerogel glazing is quantified. In evacuated aerogel glazing the space...... between the glass panes is filled with monolithic silica aerogel evacuated to a rough vacuum of approximately 1-10 hPa. The aerogel glazing does not depend on use of low emissive coatings that have the drawback of absorbing a relatively large part of the solar radiation that otherwise could reduce...

  15. Evacuation of Children

    DEFF Research Database (Denmark)

    Larusdottir, Aldis Run

    is to provide new data and information on children’s evacuation, which is a step towards including children in evacuation models and calculations. Little is known about children’s evacuation characteristics in fire compared to other parts of the population. In recent years there has been more focus on children’s...... evacuation which is reflected in a rising number of publications on the topic. This thesis comprises evacuation experiments in daycares for children 0-6 years old and elementary schools for children aged 6-15 years. Full scale evacuations were filmed allowing detailed data analysis. Findings and results...... to isolate single factors and findings. Although an engineering approach fits best to the measurable parameters, the other areas are at least equally important when investigating or predicting children’s evacuation. The key findings of the thesis are: Children are very dependent on adults for initiating...

  16. A solar collector for air-conditioning

    Energy Technology Data Exchange (ETDEWEB)

    Kose, E. [Microtherm Energietechnik GmbH, 25 - Lods (France)

    1999-03-01

    A high performance Compound Parabolic Concentrator (CPC) collector is presented. It comprises dewar type tubular vacuum tubes with an absorber coating of very low emittance, a moderately concentrating reflector and a simple thermosyphon heat removal system. The reflectors car be designed with respect to the specific needs; reflector material, concentration, truncation and symmetry car be chosen freely. The collector allows the construction of cooling systems with higher COP's without using tracking systems. Land use and costs are greatly reduced. For a certain application (optimum yearly gain in Munich with a constant collector temperature of 180 deg C) the reflector was optimized, it is a fairly asymmetrical design. A symmetrical design with a similar performance has been tested, the results are shown. (author)

  17. Gamma flux responsive self-powered detector with a tubular emitter

    International Nuclear Information System (INIS)

    Goldstein, N.P.; Todt, W.H.

    1982-01-01

    A gamma-sensitive flux detector comprises tubular emitter, an insulating core within the emitter and an insulating layer about the emitter, and a tubular conductive collector electrode about the insulating layer. The emitter material may be platinum, lead, bismuth, tantalum, tungsten; platinum preferred

  18. Auditory evacuation beacons

    NARCIS (Netherlands)

    Wijngaarden, S.J. van; Bronkhorst, A.W.; Boer, L.C.

    2005-01-01

    Auditory evacuation beacons can be used to guide people to safe exits, even when vision is totally obscured by smoke. Conventional beacons make use of modulated noise signals. Controlled evacuation experiments show that such signals require explicit instructions and are often misunderstood. A new

  19. Optimal crowd evacuation

    NARCIS (Netherlands)

    Hoogendoorn, S.P.; Daamen, W.; Duives, D.C.; Van Wageningen-Kessels, F.L.M.

    2013-01-01

    This paper deals with the optimal allocation of routes, destination, and departure times to members of a crowd, for instance in case of an evacuation or another hazardous situation in which the people need to leave the area as quickly as possible. The generic approach minimizes the evacuation times,

  20. Distal renal tubular acidosis

    Science.gov (United States)

    ... this disorder. Alternative Names Renal tubular acidosis - distal; Renal tubular acidosis type I; Type I RTA; RTA - distal; Classical RTA Images Kidney anatomy Kidney - blood and urine flow References Bose A, Monk RD, Bushinsky DA. Kidney ...

  1. Cultivation of micro-algae in closed tubular reactor

    Energy Technology Data Exchange (ETDEWEB)

    Gudin, C.; Bernard, A.; Chaumont, D.

    1983-11-01

    A description is presented of the three culture pilot utilities in activity under natural light, including glass tubular solar collector (30 mm diameter) in which the microalgae culture circulates. The utility is controled automatically (thermal regulation, gaseous transfers, continuous culture organization). The tests were conducted for the production of polysaccharides (Porphyridium cruentum, chlamydomonas mexicana) or hydrocarbons (Botriococcus braunii).

  2. Garbage collector interface

    OpenAIRE

    Ive, Anders; Blomdell, Anders; Ekman, Torbjörn; Henriksson, Roger; Nilsson, Anders; Nilsson, Klas; Robertz, Sven

    2002-01-01

    The purpose of the presented garbage collector interface is to provide a universal interface for many different implementations of garbage collectors. This is to simplify the integration and exchange of garbage collectors, but also to support incremental, non-conservative, and thread safe implementations. Due to the complexity of the interface, it is aimed at code generators and preprocessors. Experiences from ongoing implementations indicate that the garbage collector interface successfully ...

  3. Connectable solar air collectors

    Energy Technology Data Exchange (ETDEWEB)

    Oestergaard Jensen, S.; Bosanac, M.

    2002-02-01

    The project has proved that it is possible to manufacture solar air collector panels, which in an easy way can be connected into large collector arrays with integrated ducting without loss of efficiency. The developed connectable solar air collectors are based on the use of matrix absorbers in the form of perforated metal sheets. Three interconnected solar air collectors of the above type - each with an transparent area of approx. 3 m{sup 2} - was tested and compared with parallel tests on two single solar air collectors also with a transparent area of approx. 3 m{sup 2} One of the single solar air collectors has an identical absorber as the connectable solar air collectors while the absorber of the other single solar air collector was a fibre cloth. The efficiency of the three solar air collectors proved to be almost identical in the investigated range of mass flow rates and temperature differences. The solar air collectors further proved to be very efficient - as efficient as the second most efficient solar air collectors tested in the IEA task 19 project Solar Air Systems. Some problems remain although to be solved: the pressure drop across especially the connectable solar air collectors is too high - mainly across the inlets of the solar air collectors. It should, however, be possible to considerably reduce the pressure losses with a more aerodynamic design of the inlet and outlet of the solar air collectors; The connectable solar air collectors are easy connectable but the air tightness of the connections in the present form is not good enough. As leakage leads to lower efficiencies focus should be put on making the connections more air tight without loosing the easiness in connecting the solar air collectors. As a spin off of the project a simple and easy way to determine the efficiency of solar, air collectors for pre-heating of fresh air has been validated. The simple method of determining the efficiency has with success been compared with an advance method

  4. Evacuation dynamics of children

    DEFF Research Database (Denmark)

    Larusdottir, Aldis Run; Dederichs, Anne

    2010-01-01

    higher walking speeds in spiral stairs when the children are familiar with the evacuation path. Higher per-son densities and faster flow through doors were obtained among the children than found in literature on adults. Children in the younger age group are generally slower than the older children....... The children walk slower in horizontal plan than adults, however they are keen to run during evacuations, in the latter case their travel speed increases and exceeds the adults’. Since the evacuation characte-ristics of children differ in many ways from those of adults, nowadays models badly comprehend...

  5. Air/liquid collectors

    DEFF Research Database (Denmark)

    Jensen, Søren Østergaard; Olesen, Ole; Kristiansen, Finn Harken

    1997-01-01

    this kind of collectors. The modified simulation program has been used for the determination of the surplus in performance which solar heating systems with this type of solar collectors for combined preheating of ventilation air and domestic hot water will have. The simulation program and the efficiency......This report determine efficiency equations for combined air/liquid solar collectors by measurements on to different air/liquid collectors. Equations which contain all relevant informations on the solar collectors. A simulation program (Kviksol) has been modified in order to be able to handle...

  6. Simulated Evacuations Into Water

    National Research Council Canada - National Science Library

    McLean, Garnet

    2004-01-01

    .... Actual emergency data to support ditching certification are not available; there have been questions as to whether evacuation flow rates onto land are appropriate for use in ditching-related flotation time computations...

  7. Feasibility of evacuation

    International Nuclear Information System (INIS)

    1988-01-01

    The main question is whether evacuation of people is feasible in case of accidents with a nuclear power plant. The limiting conditions of this question are extracted from other studies. This study is therefore focused on a postulated accident in a newly built nuclear power plant with an electric capacity of 1000 Megawatt and a source term of one percent. In this particular case an evacuation should take place within the period between the accident and the emission of nuclear materials. Initial focus is on the administrative-organizational aspects of evacuation. Then bottlenecks in the technical implementation of evacuation are determined. An analysis is made for each potential Dutch location (Borssele, Eemshaven, Maasvlakte, Moerdijk and Westelijke Noordoostpolderdijk) of a nuclear power plant. By means of a model the following question is examined: can the population leave the danger area or be evacuated on time, under certain circumstances. It is concluded that preventive evacuation of the population from the planned locations is feasible, but at Moerdijk complications may occur because of the presence of some homes for the elderly and a nursing home. 18 refs.; 7 figs.; 2 tabs

  8. Combined solar collector and storage systems

    International Nuclear Information System (INIS)

    Norton, B.; Smyth, M.; Eames, P.; Lo, S.N.G.

    2000-01-01

    The article discusses reasons why fossil-fuelled water heating systems are included in new houses but solar systems are not. The technology and market potential for evacuated tube systems and integral collector storage systems (ICSS) are explained. The challenge for the designers of ICSSWH has been how to reduce heat loss without compromising solar energy collection. A new concept for enhanced energy storage is described in detail and input/output data are given for two versions of ICSSWH units. A table compares the costs of ICSSWH in houses compared with other (i.e. fossil fuel) water heating systems

  9. Integrated function nonimaging concentrating collector tubes for solar thermal energy

    Science.gov (United States)

    Winston, R.; Ogallagher, J. J.

    1982-09-01

    A substantial improvement in optical efficiency over contemporary external reflector evacuated tube collectors has been achieved by integrating the reflector surface into the outer glass envelope. Described are the design fabrication and test results for a prototype collector based on this concept. A comprehensive test program to measure performance and operational characteristics of a 2 sq m panel (45 tubes) has been completed. Efficiencies above 50% relative to beam at 200 C have been repeatedly demonstrated. Both the instantaneous and long term average performance of this totally stationary solar collector are comparable to those for tracking line focus parabolic troughs. The yield, reliability and stability of performance achieved have been excellent. Subcomponent assemblies and fabrication procedures have been used which are expected to be compatible with high volume production. The collector has a wide variety of applications in the 100 to 300 C range including industrial progress heat, air conditioning and Rankine engine operation.

  10. Investigation of a hybrid PVT air collector system

    Science.gov (United States)

    Haddad, S.; Touafek, K.; Mordjaoui, M.; Khelifa, A.; Tabet, I.

    2017-02-01

    The photovoltaic thermal hybrid (PVT) collectors, which simultaneously produce electricity and heat, are an alternative to photovoltaic modules and thermal collectors installed separately. Indeed, the heat extracted from the solar cell is used to heat water or air, thereby cooling the cell, and thus increasing its energy efficiency. This paper deals with a hybrid PVT air collector in which a new design has been proposed and tested. Its principle is based on the return of the preheating air to a second heating. The air thus passes twice under the solar cells before being evacuated to the outside of the collector (for space heating). The system is modular and expandable to cover large spaces to be heated. The experimental results of this novel design are presented and discussed under both normal and forced circulation. This technique of air return shows favorable results in terms of the quality of the heated air and electric power generation.

  11. Radiation energy collector

    Energy Technology Data Exchange (ETDEWEB)

    Chao, Bei Tse; Rabl, A

    1977-02-10

    The invention deals with a concentrating solar collector. Collectors of this kind often have considerable natural convection losses which are due, among other facts, to the location of the energy absorber at the outlet with the heated surface of the absorber facing the inlet opening of the collector. According to the invention, the collector is designed in such manner that the absorber is located inside a space in such a way that the radiation emitted by the absorber is reflected back to the absorber with the aid of mirror surfaces. Various designs are described.

  12. Solar collector overheating protection

    NARCIS (Netherlands)

    Slaman, M.J.; Griessen, R.P.

    Prismatic structures in a thermal solar collector are used as overheating protection. Such structures reflect incoming light efficiently back whenever less thermal power is extracted from the solar collector. Maximum thermal power is generated when the prismatic structure is surrounded by a

  13. Evacuating populations with special needs

    Science.gov (United States)

    2009-04-01

    Evacuation operations are conducted under the authority of, and based on decisions by, local and state authorities. The purpose of this primer, Evacuating Populations with Special Needs, is to provide local and state emergency managers, government of...

  14. Evacuation drill at CMS

    CERN Multimedia

    Niels Dupont-Sagorin and Christoph Schaefer

    2012-01-01

    Training personnel, including evacuation guides and shifters, checking procedures, improving collaboration with the CERN Fire Brigade: the first real-life evacuation drill at CMS took place on Friday 3 February from 12p.m. to 3p.m. in the two caverns located at Point 5 of the LHC.   CERN personnel during the evacuation drill at CMS. Evacuation drills are required by law and have to be organized periodically in all areas of CERN, both above and below ground. The last drill at CMS, which took place in June 2007, revealed some desiderata, most notably the need for a public address system. With this equipment in place, it is now possible to broadcast audio messages from the CMS control room to the underground areas.   The CMS Technical Coordination Team and the GLIMOS have focused particularly on preparing collaborators for emergency situations by providing training and organizing regular safety drills with the HSE Unit and the CERN Fire Brigade. This Friday, the practical traini...

  15. Experimental Validation and Model Verification for a Novel Geometry ICPC Solar Collector

    DEFF Research Database (Denmark)

    Perers, Bengt; Duff, William S.; Daosukho, Jirachote

    A novel geometry ICPC solar collector was developed at the University of Chicago and Colorado State University. A ray tracing model has been designed to investigate the optical performance of both the horizontal and vertical fin versions of this collector. Solar radiation is modeled as discrete...... to the desired incident angle of the sun’s rays, performance of the novel ICPC solar collector at various specified angles along the transverse and longitudinal evacuated tube directions were experimentally determined. To validate the ray tracing model, transverse and longitudinal performance predictions...... at the corresponding specified incident angles are compared to the Sandia results. A 100 m2 336 Novel ICPC evacuated tube solar collector array has been in continuous operation at a demonstration project in Sacramento California since 1998. Data from the initial operation of the array are used to further validate...

  16. Behavior-based evacuation planning

    KAUST Repository

    Rodriguez, Samuel

    2010-05-01

    In this work, we present a formulation of an evacuation planning problem that is inspired by motion planning and describe an integrated behavioral agent-based and roadmap-based motion planning approach to solve it. Our formulation allows users to test the effect on evacuation of a number of different environmental factors. One of our main focuses is to provide a mechanism to investigate how the interaction between agents influences the resulting evacuation plans. Specifically, we explore how various types of control provided by a set of directing agents effects the overall evacuation planning strategies of the evacuating agents. ©2010 IEEE.

  17. Behavior-based evacuation planning

    KAUST Repository

    Rodriguez, Samuel; Amato, Nancy M

    2010-01-01

    In this work, we present a formulation of an evacuation planning problem that is inspired by motion planning and describe an integrated behavioral agent-based and roadmap-based motion planning approach to solve it. Our formulation allows users to test the effect on evacuation of a number of different environmental factors. One of our main focuses is to provide a mechanism to investigate how the interaction between agents influences the resulting evacuation plans. Specifically, we explore how various types of control provided by a set of directing agents effects the overall evacuation planning strategies of the evacuating agents. ©2010 IEEE.

  18. Reliability of Tubular Joints

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Thoft-Christensen, Palle

    In this paper the preliminary results obtained by tests on tubular joints are presented. The joints are T-joints and the loading is static. It is the intention in continuation of these tests to perform tests on other types of joints (e.g. Y-joints) and also with dynamic loading. The purpose...... of the test is partly to obtain empirical data for the ultimate load-carrying capacity of tubular T-joints and partly to obtain some experience in performing tests with tubular joints. It is well known that tubular joints are usually designed in offshore engineering on the basis of empirical formulas obtained...... by experimental test results. Therefore, there is a need for performing experimental tests in this area....

  19. City sewer collectors biocorrosion

    Science.gov (United States)

    Ksiażek, Mariusz

    2014-12-01

    This paper presents the biocorrosion of city sewer collectors impregnated with special polymer sulphur binders, polymerized sulphur, which is applied as the industrial waste material. The city sewer collectors are settled with a colony of soil bacteria which have corrosive effects on its structure. Chemoautotrophic nitrifying bacteria utilize the residues of halites (carbamide) which migrate in the city sewer collectors, due to the damaged dampproofing of the roadway and produce nitrogen salts. Chemoorganotrophic bacteria utilize the traces of organic substrates and produce a number of organic acids (formic, acetic, propionic, citric, oxalic and other). The activity of microorganisms so enables the origination of primary and secondary salts which affect physical properties of concretes in city sewer collectors unfavourably.

  20. Development of a selective thin film and of a hermetically sealed flat plate solar collector with gas filling

    Science.gov (United States)

    Zernial, W.

    1982-12-01

    The industrial productibility of a selective absorbing thin film was investigated on the basis of reactive cathodic sputtering of Ni. On substrates of 1.8 sq m of Al, Cu, steel and stainless steel, solar absorption values up to 97% were achieved at emissivities of 5 to 10%. A prototype flat plate collector for high temperatures with two covers and hermetical sealing was developed. The technical data of the collector were measured, dependent on the selectivity of the absorber, gas fillings of dry air, argon or SF6 and the geometry and were compared with those of an evacuated flat plate collector. A hermetical sealed double flat plate collector for low temperatures was developed which has the advantage of lower no load temperatures and higher energy gain for heating swimming pool water compared with a conventional flat plate collector. The insolation values on collectors were measured and were used for a calculation of the energy gains of different collector types.

  1. Indoor guided evacuation: TIN for graph generation and crowd evacuation

    Directory of Open Access Journals (Sweden)

    Mengchao Xu

    2016-05-01

    Full Text Available This paper presents two complementary methods: an approach to compute a network data-set for indoor space of a building by using its two-dimensional (2D floor plans and limited semantic information, combined with an optimal crowd evacuation method. The approach includes three steps: (1 generate critical points in the space, (2 connect neighbour points to build up the network, and then (3 run the optimal algorithm for optimal crowd evacuation from a room to the exit gates of the building. Triangulated Irregular Network (TIN is used in the first two steps. The optimal evacuation crowd is not based on the nearest evacuation gate for a person but relies on optimal sorting of the waiting lists at each gate of the room to be evacuated. As an example case, a rectangular room with 52 persons with two gates is evacuated in 102 elementary interval times (one interval corresponds to the time for one step for normal velocity walking, whereas it would have been evacuated in not less than 167 elementary steps. The procedure for generating the customized network involves the use of 2D floor plans of a building and some common Geographic Information System (GIS functions. This method combined with the optimal sorting lists will be helpful for guiding crowd evacuation during any emergency.

  2. A comparison of three different types of collectors for process heat uses; Vergleich von drei verschiedenen Kollektortypen fuer Prozesswaermeanwendungen

    Energy Technology Data Exchange (ETDEWEB)

    Brunold, S. [Solarenergie Pruef- und Forschungsstelle SPF-ITR, Rapperswil (Switzerland); Frey, R. [Solarenergie Pruef- und Forschungsstelle SPF-ITR, Rapperswil (Switzerland); Frei, U. [Solarenergie Pruef- und Forschungsstelle SPF-ITR, Rapperswil (Switzerland)

    1995-12-31

    A comparison of the measured and simulated values of three collector types shows that evacuated tube collectors are superior to transparent-insulation flat collectors in the case of high-temperature uses. At temperatures of 150 C and above good results were obtained using evacuated tube collectors with compound parabolic concentrators manufactured by Microtherm. CORTEC collectors are suited for temperatures in the range of 100 C to 150 C provided that the surface ratio is irrelevant. Costs play a decisive role when selecting systems. The results obtained show that improved transparent-insulation flat collectors can compete with evacuated tube collectors in the 100 C to 150 C temperature range. (orig.) [Deutsch] Ein Vergleich der gemessenen und simulierten Werte der drei Kollektoren zeigt, dass die Vakuumroehrenkollektoren fuer den Einsatz in Hochtemperaturanwendungen dem mit transparenter Waermedaemmung isolierten Flachkollektor ueberlegen sind. Der Vakuumroehrenkollektor mit CPC von Microtherm erzielt gute Resultate ab 150 C und mehr. Wogegen der CORTEC-Kollektor fuer den Einsatz im Temperaturbereich zwischen 100 C und 150 C geeignet ist, solange das Flaechenverhaeltnis keine Rolle spielt. Wie fuer die meisten Anwendungen spielen die Kosten eine entscheidende Rolle fuer die Wahl des eingesetzten Systems. Die Resultate zeigen, dass ein verbesserter mit TWD ausgeruesteter Flachkollektor im Temperaturbereich von 100 C bis 150 C konkurrenzfaehig zu Vakuumroehrenkollektoren sein kann. (orig.)

  3. Tracking system for solar collectors

    Science.gov (United States)

    Butler, B.

    1980-10-01

    A tracking system is provided for pivotally mounted spaced-apart solar collectors. A pair of cables is connected to spaced-apart portions of each collector, and a driver displaces the cables, thereby causing the collectors to pivot about their mounting, so as to assume the desired orientation. The collectors may be of the cylindrical type as well as the flat-plate type. Rigid spar-like linkages may be substituted for the cables. Releasable attachments of the cables to the collectors is also described, as is a fine tuning mechanism for precisely aligning each individual collector.

  4. Biological sample collector

    Science.gov (United States)

    Murphy, Gloria A [French Camp, CA

    2010-09-07

    A biological sample collector is adapted to a collect several biological samples in a plurality of filter wells. A biological sample collector may comprise a manifold plate for mounting a filter plate thereon, the filter plate having a plurality of filter wells therein; a hollow slider for engaging and positioning a tube that slides therethrough; and a slide case within which the hollow slider travels to allow the tube to be aligned with a selected filter well of the plurality of filter wells, wherein when the tube is aligned with the selected filter well, the tube is pushed through the hollow slider and into the selected filter well to sealingly engage the selected filter well and to allow the tube to deposit a biological sample onto a filter in the bottom of the selected filter well. The biological sample collector may be portable.

  5. A solar energy collector

    Energy Technology Data Exchange (ETDEWEB)

    Vasil' yev, L.L.; Avakyan, Yu.V.; Bogdanov, V.M.; Gagiyan, L.A.; Grakovich, L.P.; Karapetyan, G.S.; Morgun, V.A.

    1984-01-01

    A collector whose primary component is a heating pipe is proposed. The evaporation zone located in the lower half of the heating pipe has an external absorption coating. Chambers that open upward and contain the evaporating fluid are mounted within this region along the top. In order to improve operational reliability of the collector, these chambers are mounted on one coated wall; the area of projection of each of the chambers onto the horizontal plane is greater than the area of the projection of each of the chambers placed above it. The coating may be in the form of photocells; a filter is mounted on the chamber side inside the evaporation zone. The evaporation zone may take the form of a cylinder with a segmented base; the photocells are mounted on a flat section of the lateral surface. The collector may be used to cool the photocells.

  6. Solar powered adsorption refrigerator with CPC collection system: Collector design and experimental test

    International Nuclear Information System (INIS)

    Gonzalez, Manuel I.; Rodriguez, Luis R.

    2007-01-01

    Solar adsorption cooling systems are usually based on the flat plate collector, whereas little attention has been paid to concentrating collectors. Compound parabolic concentrators (CPC) are a versatile class of solar collectors that can be adapted to a large variety of applications and geometries. This work presents a CPC collector whose tubular receiver contains the sorption bed and where only a portion of the receiver is exposed to sunlight. Geometric characteristics of the proposed CPC, such as the profile, the length and the height of the reflective sheet are given. A prototype of a solar adsorption chiller using this type of collector and the activated carbon-methanol working pair is described, and typical experimental results are reported. In particular, the measured solar COP ranges from 0.078 to 0.096

  7. Getting passengers out : evacuation behaviours

    NARCIS (Netherlands)

    Boer, L.C.

    2003-01-01

    When disaster strikes, mass transportation means mass evacuation. The issue is especially urgent if, despite precautions, a train comes to a stop in a tunnel and there is a fire. Adequate behaviour of passengers is a major success factor of an evacuation. Passengers should replace their original

  8. Tubular closure device

    International Nuclear Information System (INIS)

    Klahn, F.C.; Nolan, J.H.; Wills, C.

    1982-01-01

    This invention relates to a closure mechanism for closing openings such as the bore of a conduit and for releasably securing members within the bore. More particularly, this invention relates to a closure mechanism for tubular irradiation surveillance specimen assembly holders used in nuclear reactors

  9. Evacuation modeling trends

    CERN Document Server

    Abreu, Orlando; Alvear, Daniel

    2016-01-01

    This book presents an overview of modeling definitions and concepts, theory on human behavior and human performance data, available tools and simulation approaches, model development, and application and validation methods. It considers the data and research efforts needed to develop and incorporate functions for the different parameters into comprehensive escape and evacuation simulations, with a number of examples illustrating different aspects and approaches. After an overview of basic modeling approaches, the book discusses benefits and challenges of current techniques. The representation of evacuees is a central issue, including human behavior and the proper implementation of representational tools. Key topics include the nature and importance of the different parameters involved in ASET and RSET and the interactions between them. A review of the current literature on verification and validation methods is provided, with a set of recommended verification tests and examples of validation tests. The book c...

  10. Solar collector manufacturing activity, 1990

    International Nuclear Information System (INIS)

    1992-01-01

    The Solar Collector Manufacturing Activity 1990 report prepared by the Energy Information Administration (EIA) presents summary and detailed data provided by domestic manufacturers on shipments of solar thermal collectors and photovoltaic cells and modules. Summary data on solar thermal collector shipments are presented for the period 1974 through 1990. Summary data on photovoltaic cell and module shipments are presented for the period 1982 through 1990. Detailed information for solar thermal collectors and photovoltaic cells and modules are presented for 1990

  11. Solar energy collector

    Science.gov (United States)

    Brin, Raymond L.; Pace, Thomas L.

    1978-01-01

    The invention relates to a solar energy collector comprising solar energy absorbing material within chamber having a transparent wall, solar energy being transmitted through the transparent wall, and efficiently absorbed by the absorbing material, for transfer to a heat transfer fluid. The solar energy absorbing material, of generally foraminous nature, absorbs and transmits the solar energy with improved efficiency.

  12. Flat plate collector. Solarflachkollektor

    Energy Technology Data Exchange (ETDEWEB)

    Raab, N

    1979-03-29

    The invention refers to a flat solar collector with an absorber plate, which is arranged on a support and is covered by a transparent window, between which and the plate there is an air space. The previously known structures of this type had the disadvantage that the thermal expansion of the enclosed air caused considerable difficulties. The purpose of the invention is therefore to create a collector, which can be used on the modular system, retains its properties and is safe in spite of the great temperature variations. According to the invention this problem is solved by providing a compensating space in the collector, which is separated by a diaphragm from the airspace between the plate and the covering window. The airspace therefore remains sealed against the atmosphere, so that no dirt, corrosion of the inside and no condensation can reduce the efficiency of the collector. A rise in pressure due to an increase in temperature is immediately reduced by expansion of the diaphragm, which enters the compensation space. In order to increase the pressure in the airspace above the plate for increases in temperature, the compensation space is connected to the atmosphere. The diaphragm can be mirrored on the side towards the absorber, which makes the diaphragm into an insulating element, as it reflects radiated heat from the absorber.

  13. Solar collector array

    Science.gov (United States)

    Hall, John Champlin; Martins, Guy Lawrence

    2015-09-06

    A method and apparatus for efficient manufacture, assembly and production of solar energy. In one aspect, the apparatus may include a number of modular solar receiver assemblies that may be separately manufactured, assembled and individually inserted into a solar collector array housing shaped to receive a plurality of solar receivers. The housing may include optical elements for focusing light onto the individual receivers, and a circuit for electrically connecting the solar receivers.

  14. Chemical Agents: Facts about Evacuation

    Science.gov (United States)

    ... What CDC is Doing Blog: Public Health Matters Chemical Agents: Facts About Evacuation Format: Select One PDF [ ... on Facebook Tweet Share Compartir Some kinds of chemical accidents or attacks, such as a train derailment ...

  15. Building Evacuation with Mobile Devices

    OpenAIRE

    Merkel, Sabrina

    2014-01-01

    The rapidly growing world population and increasingly dense settlements demand ever-larger and more complex buildings from today's engineers. In comparison to this technological progress, a building's equipment for emergency evacuation has been hardly developed further. This work presents a concept for a building evacuation system based on mobile devices. Furthermore, various algorithms for route planning with mobile devices and for indoor localization of mobile devices are addressed.

  16. Design optimization studies for nonimaging concentrating solar collector tubes

    Science.gov (United States)

    Winston, R.; Ogallagher, J. J.

    1983-09-01

    The Integrated Stationary Evacuated Concentrator or ISEC solar collector panel which achieved the best high temperature performance ever measured with a stationary collector was examined. A development effort review and optimize the initial proof of concept design was completed. Changes in the optical design to improve the angular response function and increase the optical efficiency were determined. A recommended profile design with a concentration ratio of 1.55x and an acceptance angle of + - 35(0) was identified. Two alternative panel/module configurations are recommended based on the preferred double ended flow through design. Parasitic thermal and pumping losses show to be reducible to acceptable levels, and two passive approaches to the problem of ensuring stagnation survival are identified.

  17. Development of a selective surface vacuum collector. Final report

    Energy Technology Data Exchange (ETDEWEB)

    de Waal, H.; Simonis, F.

    1980-01-01

    To make solar energy useful for cooling applications a flat plate high performance collector, which can supply solar energy at 100 to 150/sup 0/C, has been developed. To achieve a reasonable efficiency at these temperatures the thermal heat loss must be very small. This has been obtained by (1) concentration of sunlight (c = 1.6); (2) evacuation of the collector housing to eliminate convection currents (pressure less than or equal to 4kPa); (3) spectral selective coating on the absorber; and (4) a low conductive gas in the collector housing (pressure approx. = 2kPa). The collector consists of a metal box with a glass cover hermetically sealed to it in the way double glazing units are manufactured. The sides of the V-trough concentrators support the glass cover. Measurements have been performed concerning heat loss factor and durability of the vacuum. The first prototype, fitted with a spectral selective coating of tin-oxide on enameled steel (epsilon = 0.25) showed a heat-loss of 2.0 W/m/sup 2/ /sup 0/C at 90/sup 0/C, being in reasonable agreement with calculations. Improvements with respect to the spectral selective coating and the use of a low conductive gas are necessary and will lead to a heat loss factor of about 1 W/m/sup 2/ /sup 0/C. Measurements have shown that in the chosen system the desired vacuum level can be maintained for at least 10 to 15 years.

  18. Tubular closure mechanism

    International Nuclear Information System (INIS)

    Kalen, D.D.; Mitchem, J.W.

    1982-01-01

    This invention relates to a closure mechanism for tubular irradiation surveillance specimen assembly holder used in nuclear reactors. The closure mechanism is composed of a latching member which includes a generally circular chamber with a plurality of elongated latches depending therefrom. The latching member circumscribes part of an actuator member which is disposed within the latching member so as to be axially movable. The axial movement of the actuator actuates positioning of the latches between positions in which the latches are locked and secured within the actuator member. Means, capable of being remotely manipulated, are provided to move the actuator in order to position the latches and load the articles within the tube

  19. Turning collectors for solar radiation

    Science.gov (United States)

    Barak, Amitzur Z.

    1976-01-01

    A device is provided for turning a solar collector about the polar axis so that the collector is directed toward the sun as the sun tracks the sky each day. It includes two heat-expansive elements and a shadow plate. In the morning a first expansive element is heated, expands to turn the collector to face the sun, while the second expansive element is shaded by the plate. In the afternoon the second element is heated, expands to turn the collector to face the sun, while the first is shaded by the plate.

  20. The CERN antiproton collector

    International Nuclear Information System (INIS)

    Autin, B.

    1984-01-01

    The Antiproton Collector is a new ring of much larger acceptance than the present accumulator. It is designed to receive 10 8 antiprotons per PS cycle. In order to be compatible with the Antiproton Accumulator, the momentum spread and the emittances are reduced from 6% to 0.2% and from 200 π mm mrad to 25 π mm mrad respectively. In addition to the ring itself, the new target area and the modifications to the stochastic systems of the Antiproton Accumulator are described. (orig.)

  1. The PKI collector

    Science.gov (United States)

    Rice, M. P.

    1982-07-01

    The design and manufacturing of a solar thermal collector is discussed. The collector has three primary subsystems: concentrator, receiver/fluid loop, and controls. Identical curved reflective columns are utilized in a faceted Fresnel design to support 864 one foot square flat inexpensive second-surface, silvered glass mirrors. The columns are ganged together and rotated through their centers of gravity to provide elevation tracking. The concentrator is supported by a lightweight spaceframe structure which distributes all wind and gravity loads to the base supports. The base of the structure is a track which rotates on wheels mounted on concrete piers. A parallel tube steel heat exchanger is mounted at the concentrator focal area in a well insulated, galvanized steel housing. Two rows of vertical close-packed, staggered tubes connect a mud header and a steam header. Automatic two axis tracking and operational control is provided with a microprocessor based package. Concentrator-mounted shadowbands are the basis for active tracking. A software program provides azimuthal tracking during cloudy periods.

  2. City evacuations an interdisciplinary approach

    CERN Document Server

    Binner, Jane; Branicki, Layla; Galla, Tobias; Jones, Nick; King, James; Kolokitha, Magdalini; Smyrnakis, Michalis

    2015-01-01

    Evacuating a city is a complex problem that involves issues of governance, preparedness education, warning, information sharing, population dynamics, resilience and recovery. As natural and anthropogenic threats to cities grow, it is an increasingly pressing problem for policy makers and practitioners.   The book is the result of a unique interdisciplinary collaboration between researchers in the physical and social sciences to consider how an interdisciplinary approach can help plan for large scale evacuations.  It draws on perspectives from physics, mathematics, organisation theory, economics, sociology and education.  Importantly it goes beyond disciplinary boundaries and considers how interdisciplinary methods are necessary to approach a complex problem involving human actors and increasingly complex communications and transportation infrastructures.   Using real world case studies and modelling the book considers new approaches to evacuation dynamics.  It addresses questions of complexity, not only ...

  3. Dose reduction in evacuation proctography

    International Nuclear Information System (INIS)

    Hare, C.; Halligan, S.; Bartram, C.I.; Gupta, R.; Walker, A.E.; Renfrew, I.

    2001-01-01

    The goal of this study was to reduce the patient radiation dose from evacuation proctography. Ninety-eight consecutive adult patients referred for proctography to investigate difficult rectal evacuation were studied using a digital imaging system with either a standard digital program for barium examinations, a reduced dose digital program (both with and without additional copper filtration), or Video fluoroscopy. Dose-area products were recorded for each examination and the groups were compared. All four protocols produced technically acceptable examinations. The low-dose program with copper filtration (median dose 382 cGy cm 2 ) and Video fluoroscopy (median dose 705 cGy cm 2 ) were associated with significantly less dose than other groups (p < 0.0001). Patient dose during evacuation proctography can be reduced significantly without compromising the diagnostic quality of the examination. A digital program with added copper filtration conveyed the lowest dose. (orig.)

  4. Modelling of Microclimate in collectors

    DEFF Research Database (Denmark)

    Holck, Ole

    1996-01-01

    Abstract It is important to avoid condensation in solar collectors, most of all because wetness of the absorber can damage the selective surface and cause corrosion on the absorber plate. During night time the cover of collectors will cool below ambient temperature due to thermal radiation...

  5. Nonimaging secondary concentrators for large rim angle parabolic troughs with tubular absorbers.

    Science.gov (United States)

    Ries, H; Spirkl, W

    1996-05-01

    For parabolic trough solar collectors with tubular absorbers, we design new tailored secondary concentrators. The design is applicable for any rim angle of a parabolic reflector. With the secondary, the concentration can be increased by a factor of more than 2 with a compact secondary reflector consisting of a single piece, even for the important case of a rim angle of 90 deg. The parabolic reflector can be used without changes; the reduced absorber is still tubular but smaller than the original absorber and slightly displaced toward the primary.

  6. Expandable tubulars for use in geologic structures

    Science.gov (United States)

    Spray, Jeffery A.; Svedeman, Steven; Walter, David; Mckeighan, Peter; Siebanaler, Shane; Dewhurst, Peter; Hobson, Steven; Foss, Doug; Wirz, Holger; Sharpe, Aaron; Apostal, Michael

    2014-08-12

    An expandable tubular includes a plurality of leaves formed from sheet material that have curved surfaces. The leaves extend around a portion or fully around the diameter of the tubular structure. Some of the adjacent leaves of the tubular are coupled together. The tubular is compressed to a smaller diameter so that it can be inserted through previously deployed tubular assemblies. Once the tubular is properly positioned, it is deployed and coupled or not coupled to a previously deployed tubular assembly. The tubular is useful for all types of wells and boreholes.

  7. Tubular closure mechanism

    International Nuclear Information System (INIS)

    Kalen, D.D.; Mitchem, J.W.

    1981-01-01

    An apparatus is provided for closing the bore of a tube and releasably securing articles within the tube under longitudinal load. A latching member has a cylindrical section and several circumferentially-spaced elongated latches hanging down from one end of the cylinder. An elongated actuator has integral cam and spline and is partly located within the latch with the cam radially contacting the latches and the spline projecting into the circumferential spaces between the latches. The actuator is axially movable between a position in which the latches are locked to the tube walls and a position in which the latches are secured from contact with the tube walls. Means are provided for axially moving the actuator such that the cam positions the latches; and means are also provided for engaging the articles within the tube. The closure is particularly applicable to tubular irradiation surveillance specimen assembly holders used in reactors

  8. LHCb Tag Collector

    International Nuclear Information System (INIS)

    Fernández, Paloma Fuente; Clemencic, Marco; Cousin, Nicolas

    2011-01-01

    The LHCb physics software consists of hundreds of packages, each of which is developed by one or more physicists. When the developers have some code changes that they would like released, they commit them to the version control system, and enter the revision number into a database. These changes have to be integrated into a new release of each of the physics analysis applications. Tests are then performed by a nightly build system, which rebuilds various configurations of the whole software stack and executes a suite of run-time functionality tests. A Tag Collector system has been developed using solid standard technologies to cover both the use cases of developers and integration managers. A simple Web interface, based on an AJAX-like technology, is available. Integration with SVN and Nightly Build System, is possible via a Python API. Data are stored in a relational database with the help of an ORM (Object-Relational Mapping) library.

  9. An Integrated Approach to Modeling Evacuation Behavior

    Science.gov (United States)

    2011-02-01

    A spate of recent hurricanes and other natural disasters have drawn a lot of attention to the evacuation decision of individuals. Here we focus on evacuation models that incorporate two economic phenomena that seem to be increasingly important in exp...

  10. Evacuation transportation management : task five : operational concept.

    Science.gov (United States)

    2009-06-26

    Much of what is known about evacuations is based on preparations for incidents, such as hurricanes, for which there is advance warning. With advance warning, evacuations can be planned and managed using procedures and systems that have been developed...

  11. Evacuation transportation management. Task five, Operational concept

    Science.gov (United States)

    2006-01-01

    Much of what is known about evacuations is based on preparations for incidents, such as hurricanes, for which there is advance warning. With advance warning, evacuations can be planned and managed using procedures and systems that have been developed...

  12. Evacuation Shelters - MDC_HurricaneShelter

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — A label feature class of Miami-Dade County Hurricane Evacuation Shelters (HEC) including Special Need Evacuation Centers (SNEC) and Medical Management Facilities...

  13. Evacuation of bedridden occupants: experimental research outcomes

    OpenAIRE

    Strating, N.; van Herpen, R.; Zeiler, W.

    2017-01-01

    Bedridden building occupants in hospitals and nursing homes who are not able to rescue themselves in case of a fire emergency require assistance during an evacuation. A building emergency team usually fulfils this function and will have to remove the occupants from the room. The speed at which such an evacuation is conducted however is unknown. Experiments in practice were conducted in hospitals to obtain insight in the evacuation speed and absolute evacuation times required. Furthermore, a s...

  14. Hospital evacuation; planning, assessment, performance and evaluation

    OpenAIRE

    Nero C Wabo; P Örtenwall; A Khorram-Manesh

    2012-01-01

    Objective: Malfunction in hospitals' complex internal systems, or extern threats, may result in a hospital evacuation. Factors contributing to such evacuation must be identified, analyzed and action plans should be prepared. Our aims in this study were 1) to evaluate the use of risk and vulnerability analysis as a basis for hospital evacuation plan, 2) to identify risks/hazards triggering an evacuation and evaluate the respond needed and 3) to propose a template with main key points for plann...

  15. Current collectors for improved safety

    Science.gov (United States)

    Abdelmalak, Michael Naguib; Allu, Srikanth; Dudney, Nancy J.; Li, Jianlin; Simunovic, Srdjan; Wang, Hsin

    2017-12-19

    A battery electrode assembly includes a current collector with conduction barrier regions having a conductive state in which electrical conductivity through the conduction barrier region is permitted, and a safety state in which electrical conductivity through the conduction barrier regions is reduced. The conduction barrier regions change from the conductive state to the safety state when the current collector receives a short-threatening event. An electrode material can be connected to the current collector. The conduction barrier regions can define electrical isolation subregions. A battery is also disclosed, and methods for making the electrode assembly, methods for making a battery, and methods for operating a battery.

  16. AEROSOL PARTICLE COLLECTOR DESIGN STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S; Richard Dimenna, R

    2007-09-27

    A computational evaluation of a particle collector design was performed to evaluate the behavior of aerosol particles in a fast flowing gas stream. The objective of the work was to improve the collection efficiency of the device while maintaining a minimum specified air throughput, nominal collector size, and minimal power requirements. The impact of a range of parameters was considered subject to constraints on gas flow rate, overall collector dimensions, and power limitations. Potential improvements were identified, some of which have already been implemented. Other more complex changes were identified and are described here for further consideration. In addition, fruitful areas for further study are proposed.

  17. Four-collector flux sensor

    International Nuclear Information System (INIS)

    Wiegand, W.J. Jr.; Bullis, R.H.; Mongeon, R.J.

    1980-01-01

    A flowmeter based on ion drift techniques was developed for measuring the rate of flow of a fluid through a given cross-section. Ion collectors are positioned on each side of an immediately adjacent to ion source. When air flows axially through the region in which ions are produced and appropriate electric fields are maintained between the collectors, an electric current flows to each collector due to the net motion of the ions. The electric currents and voltages and other parameters which define the flow are combined in an electric circuit so that the flux of the fluid can be determined. (DN)

  18. Parabolic Trough Solar Collector Initial Trials

    Directory of Open Access Journals (Sweden)

    Ghalya Pikra

    2012-03-01

    Full Text Available This paper discusses initial trials of parabolic trough solar collector (PTSC in Bandung. PTSC model consists of concentrator, absorber and tracking system. Concentrator designs are made with 2m aperture width, 6m length and 0.75m focal distance. The design is equipped with an automatic tracking system which is driven using 12V and 24Watt DC motor with 0.0125rpm rotational speed. Absorber/receiver is designed with evacuated tube type, with 1 inch core diameter and tube made of AISI304 and coated with black oxide, the outer tube is borosilicate glass with a 70 mm diameter and 1.5 m length. Working fluid stored in single type of thermal storage tank, a single phase with 37.7 liter volume. PTSC model testing carried out for 2 hours and 10 minutes produces heat output and input of 11.5 kW and 0.64 kW respectively. 

  19. Engineering development studies for integrated evacuated CPC arrays

    Science.gov (United States)

    Winston, R.

    1982-04-01

    An evacuated tube concentrator which achieves respectable high temperature performance (100 C to 300 C) was developed. The design concept utilizes nonimaging CPC type concentration integrated into each tube by shaping the outer glass vacuum envelope. The detailed design, prototype fabrication and preliminary test measurements are reviewed. In addition the results of this first study specifically devoted to engineering development questions related to practical applications of this collector concept are summarized. Questions having to do with the deployment of medium to large area arrays, optimizations of the manifolding of individual tube panels, selected near term applications (with an emphasis on residential cooling based on Rankine driven chillers) and long term performance projections are addressed.

  20. Tsunami evacuation buildings and evacuation planning in Banda Aceh, Indonesia.

    Science.gov (United States)

    Yuzal, Hendri; Kim, Karl; Pant, Pradip; Yamashita, Eric

    Indonesia, a country of more than 17,000 islands, is exposed to many hazards. A magnitude 9.1 earthquake struck off the coast of Sumatra, Indonesia, on December 26, 2004. It triggered a series of tsunami waves that spread across the Indian Ocean causing damage in 11 countries. Banda Aceh, the capital city of Aceh Province, was among the most damaged. More than 31,000 people were killed. At the time, there were no early warning systems nor evacuation buildings that could provide safe refuge for residents. Since then, four tsunami evacuation buildings (TEBs) have been constructed in the Meuraxa subdistrict of Banda Aceh. Based on analysis of evacuation routes and travel times, the capacity of existing TEBs is examined. Existing TEBs would not be able to shelter all of the at-risk population. In this study, additional buildings and locations for TEBs are proposed and residents are assigned to the closest TEBs. While TEBs may be part of a larger system of tsunami mitigation efforts, other strategies and approaches need to be considered. In addition to TEBs, robust detection, warning and alert systems, land use planning, training, exercises, and other preparedness strategies are essential to tsunami risk reduction.

  1. Tubular nanostructured materials for bioapplications

    Science.gov (United States)

    Xie, Jining; Chen, Linfeng; Srivatsan, Malathi; Varadan, Vijay K.

    2009-03-01

    Tubular nanomaterials possess hollow structures as well as high aspect ratios. In addition to their unique physical and chemical properties induced by their nanoscale dimensions, their inner voids and outer surfaces make them ideal candidates for a number of biomedical applications. In this work, three types of tubular nanomaterials including carbon nanotubes, hematite nanotubes, and maghemite nanotubes, were synthesized by different chemical techniques. Their structural and crystalline properties were characterized. For potential bioapplications of tubular nanomaterials, experimental investigations were carried out to demonstrate the feasibility of using carbon nanotubes, hematite nanotubes, and maghemite nanotubes in glucose sensing, neuronal growth, and drug delivery, respectively. Preliminary results show the promise of tubular nanomaterials in future biomedical applications.

  2. Optimum selection of solar collectors for a solar-driven ejector air conditioning system by experimental and simulation study

    International Nuclear Information System (INIS)

    Zhang Wei; Ma Xiaoli; Omer, S.A.; Riffat, S.B.

    2012-01-01

    Highlights: ► Three solar collectors have been compared to drive ejector air conditioning system. ► A simulation program was constructed to study the effect parameters. ► The outdoor test were conducted to validate the solar collector modeling. ► Simulation program was found to predict solar collector performance accurately. ► The optimal design of solar collector system was carried out. - Abstract: In this paper, three different solar collectors are selected to drive the solar ejector air conditioning system for Mediterranean climate. The performance of the three selected solar collector are evaluated by computer simulation and lab test. Computer model is incorporated with a set of heat balance equations being able to analyze heat transfer process occurring in separate regions of the collector. It is found simulation and test has a good agreement. By the analysis of the computer simulation and test result, the solar ejector cooling system using the evacuated tube collector with selective surface and high performance heat pipe can be most economical when operated at the optimum generating temperature of the ejector cooling machine.

  3. High-temperature, high-pressure bonding of nested tubular metallic components

    International Nuclear Information System (INIS)

    Quinby, T.C.

    1980-01-01

    This invention is a tool for effecting high-temperature, high compression bonding between the confronting faces of nested, tubular, metallic components. In a typical application, the tool is used to produce tubular target assemblies for irradiation in nuclear reactors or particle accelerators, the target assembly comprising a uranium foil and an aluminum-alloy substrate. The tool preferably is composed throughout of graphite. It comprises a tubular restraining member in which a mechanically expandable tubular core is mounted to form an annulus with the member. The components to be bonded are mounted in nested relation in the annulus. The expandable core is formed of individually movable, axially elongated segments whose outer faces cooperatively define a cylindrical pressing surface and whose inner faces cooperatively define two opposed, inwardly tapered, axial bores. Tapered rams extend respectively into the bores. The loaded tool is mounted in a conventional hot-press provided with evacuation means, heaters for maintaining its interior at bonding temperature, and hydraulic cylinders for maintaining a selected inwardly directed pressure on the tapered rams. With the hotpress evacuated and the loaded tool at the desired temperature, the cylinders are actuated to apply the selected pressure to the rams. The rams in turn expand the segmented core to maintain the nested components in compression against the restraining member. These conditions are maintained until the confronting faces of the nested components are joined in a continuous, uniform bond characterized by high thermal conductivity

  4. High-temperature, high-pressure bonding of nested tubular metallic components

    Science.gov (United States)

    Quinby, T.C.

    A tool is described for effecting high-temperature, high-compression bonding between the confronting faces of nested, tubular, metallic components. In a typical application, the tool is used to produce tubular target assemblies for irradiation in nuclear reactors or particle accelerators. The target assembly comprising a uranum foil and an aluninum-alloy substrate. The tool is composed of graphite. It comprises a tubular restraining member in which a mechanically expandable tubular core is mounted to form an annulus. The components to be bonded are mounted in nested relation in the annulus. The expandable core is formed of individually movable, axially elongated segments whose outer faces cooperatively define a cylindrical pressing surface and whose inner faces cooperatively define two opposed, inwardly tapered, axial bores. Tapered rams extend into the bores. The loaded tool is mounted in a conventional hot-press provided with evacuation means, heaters for maintaining its interior at bonding temperature, and hydraulic cylinders for maintaining a selected inwardly directed pressure on the tapered rams. With the hot-press evacuated and the loaded tool at the desired temperature, the cylinders are actuated to apply the selected pressure to the rams. The rams in turn expand the segmented core to maintain the nested components in compression against the restraining member. These conditions are maintained until the confronting faces of the nested components are joined in a continuous, uniform bond characterized by high thermal conductivity.

  5. Comparison of the optics of non-tracking and novel types of tracking solar thermal collectors for process heat applications up to 300{sup o}C

    Energy Technology Data Exchange (ETDEWEB)

    Grass, C.; Schoelkopf, W.; Staudacher, L.; Hacker, Z. [Bavarian Centre for Applied Energy Research, ZAE Bayern Division 4, Garching (Germany)

    2004-03-01

    Evacuated CPC (compound parabolic concentrator) collectors with non-tracking reflectors are compared with two novel tracking collectors: a parabolic trough and an evacuated tube collector with integrated tracking reflector. Non-tracking low concentrating CPC collectors are mostly mounted in east-west direction with a latitude dependent slope angle. They are suitable at most for working temperatures up to 200-250 {sup o}C. We present a tracking evacuated tube-collector with a trough-like concentrating mirror. Single-axis tracking of the mirror is realized with a magnetic mechanism. The mirror is mounted inside the evacuated tube and hence protected from environmental influences. One axis tracking in combination with a small acceptance angle allows for higher concentration as compared to non-tracking concentrating collectors. Ray-tracing analysis shows a half acceptance angle of about 5.7{sup o} at geometrical concentration ratio of 3.2. Losses of well constructed evacuated tube collectors (heat conductivity through the manifolds inside the thermally insulated terminating housing are low) are dominated by radiation losses of the absorber. Hence, reducing the absorber size can lead to higher efficiencies at high operating temperature levels. With the presented collector we aim for operating temperatures up to 350 {sup o}C. At temperatures of 300 {sup o}C we expect with anti-reflective coating of the glass tube and a selective absorber coating efficiencies of 0.65. This allows for application in industrial process heat generation, high efficient solar cooling and power generation. A first prototype, equipped with a standard glass tube and a black paint absorber coating, was tested at ZAE Bayern. The optical efficiency was measured to be 0.71. This tube-collector is compared by ray-tracing with non-tracking market available tube-collectors with geometrical concentration ratios up to 1.1 and with a low cost parabolic trough collector of Industrial Solar Technology (IST

  6. Pedestrian and Evacuation Dynamics 2005

    CERN Document Server

    Gattermann, Peter; Knoflacher, Hermann; Schreckenberg, Michael

    2007-01-01

    Due to an increasing number of reported catastrophes all over the world, the safety especially of pedestrians today, is a dramatically growing field of interest, both for practitioners as well as scientists from various disciplines. The questions arising mainly address the dynamics of evacuating people and possible optimisations of the process by changing the architecture and /or the procedure. This concerns not only the case of ships, stadiums or buildings, all with restricted geometries, but also the evacuation of complete geographical regions due to natural disasters. Furthermore, also ‘simple’ crowd motion in ‘relaxed’ situations poses new questions with respect to higher comfort and efficiency since the number of involved persons at large events is as high as never before. In addition, as a new research topic in this field, collective animal behaviour is attracting increasing attention. All this was in the scope of the conference held in Vienna, September 28–30, 2005, the third one in a series ...

  7. Design package for concentrating solar collector panels

    Energy Technology Data Exchange (ETDEWEB)

    1978-08-01

    Information used to evaluate the design of the Northrup concentrating collector is presented. Included are the system performance specifications, the applications manual, and the detailed design drawings of the collector. The Northrup concentrating solar collector is a water/glycol/working fluid type, dipped galvanized steel housing, transparent acrylic Fresnel lens cover, copper absorber tube, fiber glass insulation and weighs 98 pounds. The gross collector area is about 29.4/sup 2/ per collector. A collector assembly includes four collector units within a tracking mount array.

  8. Evacuation exercise at the Kindergarten

    CERN Multimedia

    2001-01-01

    Every year fire evacuation exercises are organized through out CERN and our facility's Kindergarten is no exception. Just a few weeks ago, a fire simulation was carried out in the Kindergarten kitchen facility using synthetic smoke. The purpose of the exercise was to teach staff to react in a disciplined and professional manner when in the presence of danger. The simulation is always carried out at a random time so as to ensure that people in the area under the test are not aware of the exercise. For the Kindergarten the exercise was held early in the school year so as to train those who are new to the establishment. The evacuation was a complete success and all went as it was supposed to. When the children and teachers smelt smoke they followed the prescribed evacuation routes and left the building immediately. Once outside the situation was revealed as an exercise and everyone went back to business as usual, everyone that is, except the fire brigade and fire inspector.  The fire brigade checked t...

  9. Solar radiation on a catenary collector

    Science.gov (United States)

    Crutchik, M.; Appelbaum, J.

    1992-01-01

    A tent-shaped structure with a flexible photovoltaic blanket acting as a catenary collector is presented. The shadow cast by one side of the collector produces a shadow on the other side of the collector. This self-shading effect is analyzed. The direct beam, the diffuse, and the albedo radiation on the collector are determined. An example is given for the insolation on the collector operating on Viking Lander 1 (VL1).

  10. Design package for concentrating solar collector panels

    Science.gov (United States)

    1978-01-01

    Information used to evaluate the design of the Northrup concentrating collector is presented. Included are the system performance specifications, the applications manual, and the detailed design drawings of the collector. The collector is a water/glycol/working fluid type, with a dipped galvanized steel housing, transparent acrylic Fresnel lens cover, copper absorber tube, and fiber glass insulation. It weights 98 pounds. A collector assembly includes four collector units within a tracking mount array.

  11. A distributed garbage collector for active objects

    OpenAIRE

    Puaut , Isabelle

    1993-01-01

    This paper introduces an algorithm that performs garbage collection in distributed systems of active objects (i.e., objects having their own threads of control). The proposed garbage collector is made of a set of local garbage collectors, one per node, loosely coupled to a global garbage collector. The novelties of the proposed garbage collector come from the fact that local garbage collectors need not be synchronized with each other for detecting garbage objects and that faulty communication...

  12. Standard Practice for Exposure of Cover Materials for Solar Collectors to Natural Weathering Under Conditions Simulating Operational Mode

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1995-01-01

    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 and health practices and determine the applicability of regulatory limitations prior to use.

  13. Nocturnal reverse flow in water-in-glass evacuated tube solar water heaters

    International Nuclear Information System (INIS)

    Tang, Runsheng; Yang, Yuqin

    2014-01-01

    Highlights: • Performance of water-in-glass evacuated tube solar water heaters (SWH) at night was studied. • Experimental measurements showed that reverse flow occurred in SWHs at night. • Reverse flow in SWHs was very high but the heat loss due to reverse flow was very low. • Reverse flow seemed not sensitive to atmospheric clearness but sensitive to collector tilt-angle. - Abstract: In this work, the thermal performance of water-in-glass evacuated tube solar water heaters (SWH) at nights was experimentally investigated. Measurements at nights showed that the water temperature in solar tubes was always lower than that in the water tank but higher than the ambient air temperature and T exp , the temperature of water inside tubes predicted in the case of the water in tubes being naturally cooled without reverse flow. This signified that the reverse flow in the system occurred at nights, making the water in solar tubes higher than T exp . It is found that the reverse flow rate in the SWH, estimated based on temperature measurements of water in solar tubes, seemed not sensitive to the atmospheric clearness but sensitive to the collector tilt-angle, the larger the tilt-angle of the collector, the higher the reverse flow rate. Experimental results also showed that, the reverse flow in the SWH was much higher as compared to that in a thermosyphonic domestic solar water heater with flat-plate collectors, but the heat loss from collectors to the air due to reverse flow in SWHs was very small and only took about 8–10% of total heat loss of systems

  14. Evacuation decision-making: process and uncertainty

    International Nuclear Information System (INIS)

    Mileti, D.; Sorensen, J.; Bogard, W.

    1985-09-01

    The purpose was to describe the processes of evacuation decision-making, identify and document uncertainties in that process and discuss implications for federal assumption of liability for precautionary evacuations at nuclear facilities under the Price-Anderson Act. Four major categories of uncertainty are identified concerning the interpretation of hazard, communication problems, perceived impacts of evacuation decisions and exogenous influences. Over 40 historical accounts are reviewed and cases of these uncertainties are documented. The major findings are that all levels of government, including federal agencies experience uncertainties in some evacuation situations. Second, private sector organizations are subject to uncertainties at a variety of decision points. Third, uncertainties documented in the historical record have provided the grounds for liability although few legal actions have ensued. Finally it is concluded that if liability for evacuations is assumed by the federal government, the concept of a ''precautionary'' evacuation is not useful in establishing criteria for that assumption. 55 refs., 1 fig., 4 tabs

  15. Routes to effective evacuation planning primer series : evacuating populations with special needs.

    Science.gov (United States)

    2009-04-01

    Evacuation operations are conducted under the authority of, and based on decisions by, local and state authorities. The purpose of this primer, Evacuating Populations with Special Needs, is to provide local and state emergency managers, government of...

  16. Alternative evacuation strategies for nuclear power accidents

    International Nuclear Information System (INIS)

    Hammond, Gregory D.; Bier, Vicki M.

    2015-01-01

    In the U.S., current protective-action strategies to safeguard the public following a nuclear power accident have remained largely unchanged since their implementation in the early 1980s. In the past thirty years, new technologies have been introduced, allowing faster computations, better modeling of predicted radiological consequences, and improved accident mapping using geographic information systems (GIS). Utilizing these new technologies, we evaluate the efficacy of alternative strategies, called adaptive protective action zones (APAZs), that use site-specific and event-specific data to dynamically determine evacuation boundaries with simple heuristics in order to better inform protective action decisions (rather than relying on pre-event regulatory bright lines). Several candidate APAZs were developed and then compared to the Nuclear Regulatory Commission’s keyhole evacuation strategy (and full evacuation of the emergency planning zone). Two of the APAZs were better on average than existing NRC strategies at reducing either the radiological exposure, the population evacuated, or both. These APAZs are especially effective for larger radioactive plumes and at high population sites; one of them is better at reducing radiation exposure, while the other is better at reducing the size of the population evacuated. - Highlights: • Developed framework to compare nuclear power accident evacuation strategies. • Evacuation strategies were compared on basis of radiological and evacuation risk. • Current strategies are adequate for smaller scale nuclear power accidents. • New strategies reduced radiation exposure and evacuation size for larger accidents

  17. Injuries in air transport emergency evacuations.

    Science.gov (United States)

    1979-02-01

    Twelve air transport evacuations are reviewed. Injuries are discussed with emphasis on configurational and procedural contributing factors. Recommendations and information about possible methods of reducing injuries are provided.

  18. Routine ultrasound guided evacuation of first trimester missed abortion versus blind evacuation

    OpenAIRE

    Mostafa Abdulla Elsayed

    2014-01-01

    Background: The clinical management of miscarriage has changed little over the years and many women undergo surgical uterine evacuation. Surgical evacuation of the uterine contents in missed abortion is a challenge to the obstetrician as it is done blindly. The current study recommends the use of ultrasound guided surgical evacuation. It serves two important advantages; the first is to complete evacuation without the need of additional step. The second is to protect against uterine perforatio...

  19. Standard Practice for Exposure of Solar Collector Cover Materials to Natural Weathering Under Conditions Simulating Stagnation Mode

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1992-01-01

    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 t...

  20. Performance of evaporator-collector and air collector in solar assisted heat pump dryer

    International Nuclear Information System (INIS)

    Hawlader, M.N.A.; Rahman, S.M.A.; Jahangeer, K.A.

    2008-01-01

    A solar assisted heat pump dryer has been designed, fabricated and tested. This paper presents the performance of the evaporator-collector and the air collector when operated under the same meteorological conditions. ASHRAE standard procedure for collector testing has been followed. The evaporator-collector of the heat pump is acting directly as the solar collector, and the temperature of the refrigerant at the inlet to the evaporator-collector always remained below the ambient temperature. Because of the rejection of sensible and latent heats of air at the dehumidifier, the temperature at the inlet to the air collector is lower than that of the ambient air. Hence, the thermal efficiency of the air collector also increases due to a reduction of losses from the collector. The efficiencies of the evaporator-collector and the air collector were found to vary between 0.8-0.86 and 0.7-0.75, respectively, when operated under the meteorological conditions of Singapore

  1. ADVANCED HYBRID PARTICULATE COLLECTOR

    Energy Technology Data Exchange (ETDEWEB)

    Ye Zhuang; Stanley J. Miller; Michelle R. Olderbak; Rich Gebert

    2001-12-01

    A new concept in particulate control, called an advanced hybrid particulate collector (AHPC), is being developed under funding from the U.S. Department of Energy. The AHPC combines the best features of electrostatic precipitators (ESPs) and baghouses in an entirely novel manner. The AHPC concept combines fabric filtration and electrostatic precipitation in the same housing, providing major synergism between the two methods, both in the particulate collection step and in transfer of dust to the hopper. The AHPC provides ultrahigh collection efficiency, overcoming the problem of excessive fine-particle emissions with conventional ESPs, and solves the problem of reentrainment and re-collection of dust in conventional baghouses. Phase I of the development effort consisted of design, construction, and testing of a 5.7-m{sup 3}/min (200-acfm) working AHPC model. Results from both 8-hr parametric tests and 100-hr proof-of-concept tests with two different coals demonstrated excellent operability and greater than 99.99% fine-particle collection efficiency. Since all of the developmental goals of Phase I were met, the approach was scaled up in Phase II to a size of 255 m{sup 3}/min (9000 acfm) (equivalent in size to 2.5 MW) and was installed on a slipstream at the Big Stone Power Plant. For Phase II, the AHPC at Big Stone Power Plant was operated continuously from late July 1999 until mid-December 1999. The Phase II results were highly successful in that ultrahigh particle collection efficiency was achieved, pressure drop was well controlled, and system operability was excellent. For Phase III, the AHPC was modified into a more compact configuration, and components were installed that were closer to what would be used in a full-scale commercial design. The modified AHPC was operated from April to July 2000. While operational results were acceptable during this time, inspection of bags in the summer of 2000 revealed some membrane damage to the fabric that appeared to be

  2. Installation package for concentrating solar collector panels

    Science.gov (United States)

    1978-01-01

    The concentrating solar collector panels comprise a complete package array consisting of collector panels using modified Fresnel prismatic lenses for a 10 to 1 concentrating ratio, supporting framework, fluid manifolding and tracking drive system, and unassembled components for field erection.

  3. A Study on the Development of Nonglass Solar Vacuum Tube Collector

    International Nuclear Information System (INIS)

    Oh, Seung Jin

    2008-02-01

    Nature has been providing us energy from the beginning of the world. However human has hardly used it wisely. Solar energy is a kind of renewable energy from the nature. This study has been carried out to study the use of solar energy as it is harnessed in the form of thermal energy. Solar energy is one of the most promising energy resources such as hydrogen, biomass, wind and geothermal energy, because it is clean and inexhaustible. Space heating in buildings can be provided from solar energy by systems that are similar in many respects to water heater systems. By tapping into solar energy, we can not only solve the problem of energy shortage, but also can protect the environment and benefit the human beings. There are currently two types of evacuated tube; a single glass tube and a double glass tube. The former consists of a single glass tube which contains a flat or curved aluminium plate attached to a copper heat pipe or water flow pipe. The latter consists of rows of parallel transparent glass tubes, each of which contains an absorber tube. Evacuated tube collectors introduced above, however, pose some problems as they break rather easily under mechanical stresses. This paper introduces some preliminary results in design and fabrication of a non-glass solar vacuum tube collector in which the thermosyphon(heat pipe)made of copper is used as a heat transfer device. A series of tests have been performed to assess the ability of a non-glass solar vacuum tube collector. The series of experiments are as follows: 1)Vacuum level inside a vacuum tube. 2)Effects of the air remaining inside a vacuum tube on the temperature on the absorber plate. 3)Comparison of a non-glass vacuum solar collector with a single glass evacuated tube(SEIDO 5). Different vacuum levels inside non-glass vacuum tubes were applied to check any leakage or unexpected physical or chemical developments with time. The vacuum level changed from 10 -2 torr to 5torr in 5 days due to air infiltration from

  4. Evacuation a serious game for preparation

    NARCIS (Netherlands)

    Kolen, B.; Thonus, B.; van Zuilekom, Kasper M.; de Romph, E.

    2011-01-01

    Mass evacuation is a measure to reduce possible loss of life in the case of potential disasters. Planning for mass evacuation is only useful if these plans are tested and evaluated by government and the public in reality or in simulated events. As a result, any prior experience is likely to be

  5. Investigations on efficiencies of HT solar collectors for different flow rates and collector tilts

    DEFF Research Database (Denmark)

    Chen, Ziqian; Perers, Bengt; Furbo, Simon

    2013-01-01

    Two HT solar collectors for solar heating plants from Arcon Solvarme A/S are tested in a laboratory test facility for solar collectors at Technical University of Denmark (DTU). The collectors are designed in the same way. However, one solar collector is equipped with an ETFE foil between the abso......Two HT solar collectors for solar heating plants from Arcon Solvarme A/S are tested in a laboratory test facility for solar collectors at Technical University of Denmark (DTU). The collectors are designed in the same way. However, one solar collector is equipped with an ETFE foil between...... the absorber and the cover glass and the other is without ETFE foil. The efficiencies for the collectors are tested at different flow rates and tilt. On the basis of the measured efficiencies, the efficiencies for the collectors as functions of flow rates are obtained. The calculated efficiencies are in good...

  6. Pedestrian and Evacuation Dynamics 2012

    CERN Document Server

    Kirsch, Uwe; Schreckenberg, Michael

    2014-01-01

    The 6th International Conference on Pedestrian and Evacuation Dynamics conference (PED2012) showcased research on human locomotion. This book presents the proceedings of PED2012. Humans have walked for eons; our drive to settle the globe began with a walk out of Africa. However, much remains to discover. As the world moves toward sustainability while racing to assess and accommodate climate change, research must provide insight on the physical requirements of walking, the dynamics of pedestrians on the move and more. We must understand, predict and simulate pedestrian behaviour, to avoid dangerous situations, to plan for emergencies, and not least, to make walking more attractive and enjoyable. PED2012 offered 70 presentations and keynotes and 70 poster presentations covering new and improved mathematical models, describing new insights on pedestrian behaviour in normal and emergency cases and presenting research based on sensors and advanced observation methods. These papers offer a starting point for innova...

  7. WWER-1000/320 steam generator collector rupture. Radiological consequences

    Energy Technology Data Exchange (ETDEWEB)

    Ivanova, A; Sartmadzhiev, A; Balabanov, E [Energoproekt, Sofia (Bulgaria)

    1996-12-31

    A model describing a hypothetical accident with direct release of primary coolant to the atmosphere is proposed. Cover lifting of the primary collector due to a rupture of the fixing bolts leads to a coolant release. The initial and boundary conditions of the accident scenario have been selected to provide for the most unfavorable conditions. The total release of primary coolant during the first 15 min of transient are estimated to 50.8 tons, of these 48.5 t with the initial activity in the primary coolant circuit. Without evacuation or sheltering, after 7 days of exposure, the expected dose at the boundary of the restricted zone is 0.0182 Sv for the whole body and 0.184 Sv for the thyroid gland. The effective equivalent dose on the site would be 0.0521 Sv. As a result of the analysis it is concluded that the steam generator collector rupture is not jeopardizing the core heat removal even with a minimum configuration of ECCS as the cooling is accomplished through the steam generators. The radiological consequences of the accident would be relatively small if an emergency procedure is applied at the 15-th minute of the transient. 1 ref.

  8. The photo-thermal industry. Why evacuated collectors are the most profitable solar application

    International Nuclear Information System (INIS)

    Mahdjuri, F.

    1994-01-01

    The reasons for the increasing popularity of using solar energy as one way of meeting the global energy demand are outlined. However, the solar energy industry needs to approach marketing its products rationally and carefully to assure future growth of its market share of power production. The need for clear marketing strategies alongside a good understanding of solar technology are emphasised. (UK)

  9. THERMAL PERFORMANCE OF FLAT PLATE SOLAR COLLECTOR

    Directory of Open Access Journals (Sweden)

    TABET I.

    2017-06-01

    Full Text Available In this paper, a theoretical and experimental studyof flat platesolar water collector with reflectors.A mathematical model based on energy balance equations saw the thermal behavior of the collector is investigated. The experimental test was made at the unit research applies in renewable energy (URAER located in southern Algeria.An increase of 23% for solar radiation incident on the collector surface with the addition of the planers reflectors in the day of May, this increase causes an improvement of the performance of the collector,the fluid temperature increases with an average of 5%. Thetests conducted on the flat plate solar water collector in open circuit enabled the determination of thermal performance of the collector by estimating the daily output The thermal efficiency of the collector ranges from 1% -63% during the day, a mean value of 36%obtained.

  10. Solar Air Collectors for Space Heating and Ventilation Applications—Performance and Case Studies under Romanian Climatic Conditions

    Directory of Open Access Journals (Sweden)

    Sanda Budea

    2014-06-01

    Full Text Available Solar air collectors have various applications: on the one hand, they can be used for air heating in cold seasons; on the other hand they can be used in summer to evacuate the warm and polluted air from residential, offices, industrial, and commercial buildings. The paper presents experimental results of a solar collector air, under the climatic conditions of the Southeastern Europe. The relationships between the direct solar irradiation, the resulting heat flow, the air velocity at the outlet, the air flow rate, the nominal regime of the collector and the efficiency of conversion of solar energy into thermal energy are all highlighted. Thus, it was shown that after a maximum 50 min, solar air collectors, with baffles and double air passage can reach over 50% efficiency for solar irradiation of 900–1000 W/m2. The article also presents a mathematical model and the results of a computational program that allows sizing solar collectors for the transfer of air, with the purpose of improving the natural ventilation of buildings. The article is completed with case studies, sizing the area to be covered with solar collectors, to ensure ventilation of a house with two floors or for an office building. In addition, the ACH (air change per hour coefficient was calculated and compared.

  11. Collector ring project at FAIR

    International Nuclear Information System (INIS)

    Dolinskii, A; Blell, U; Dimopoulou, C; Gorda, O; Leibrock, H; Litvinov, S; Laier, U; Schurig, I; Weinrich, U; Berkaev, D; Koop, I; Starostenko, A; Shatunov, P

    2015-01-01

    The collector ring is a dedicated ring for fast cooling of ions coming from separators at the FAIR project. To accommodate optimal technical solutions, a structure of a magnet lattice was recently reviewed and modified. Consequently, more appropriate technical solutions for the main magnets could be adopted. A general layout and design of the present machine is shown. The demanding extraction schemes have been detailed and open design issues were completed. (paper)

  12. Assessment of Energy, Environmental and Economic Performance of a Solar Desiccant Cooling System with Different Collector Types

    Directory of Open Access Journals (Sweden)

    Giovanni Angrisani

    2014-10-01

    Full Text Available Desiccant-based air handling units can achieve reductions in greenhouse gas emissions and energy savings with respect to conventional air conditioning systems. Benefits are maximized when they interact with renewable energy technologies, such as solar collectors. In this work, experimental tests and data derived from scientific and technical literature are used to implement a model of a solar desiccant cooling system, considering three different collector technologies (air, flat-plate and evacuated collectors. Simulations were then performed to compare the energy, environmental and economic performance of the system with those of a desiccant-based unit where regeneration thermal energy is supplied by a natural gas boiler, and with those of a conventional air-handling unit. The only solution that allows achieving the economic feasibility of the solar desiccant cooling unit consists of 16 m2 of evacuated solar collectors. This is able to obtain, with respect to the reference system, a reduction of primary energy consumption and of the equivalent CO2 emissions of 50.2% and 49.8%, respectively, but with a payback time of 20 years.

  13. Factors associated with high-rise evacuation: qualitative results from the World Trade Center Evacuation Study.

    Science.gov (United States)

    Gershon, Robyn R M; Qureshi, Kristine A; Rubin, Marcie S; Raveis, Victoria H

    2007-01-01

    Due to the fact that most high-rise structures (i.e., >75 feet high, or eight to ten stories) are constructed with extensive and redundant fire safety features, current fire safety procedures typically only involve limited evacuation during minor to moderate fire emergencies. Therefore, full-scale evacuation of high-rise buildings is highly unusual and consequently, little is known about how readily and rapidly high-rise structures can be evacuated fully. Factors that either facilitate or inhibit the evacuation process remain under-studied. This paper presents results from the qualitative phase of the World Trade Center Evacuation Study, a three-year, five-phase study designed to improve our understanding of the individual, organizational, and environmental factors that helped or hindered evacuation from the World Trade Center (WTC) Towers 1 and 2, on 11 September 2001. Qualitative data from semi-structured, in-depth interviews and focus groups involving WTC evacuees were collected and analyzed. On the individual level, factors that affected evacuation included perception of risk (formed largely by sensory cues), preparedness training, degree of familiarity with the building, physical condition, health status, and footwear. Individual behavior also was affected by group behavior and leadership. At the organizational level, evacuation was affected by worksite preparedness planning, including the training and education of building occupants, and risk communication. The environmental conditions affecting evacuation included smoke, flames, debris, general condition and degree of crowdedness on staircases, and communication infrastructure systems (e.g., public address, landline, cellular and fire warden's telephones). Various factors at the individual, organizational, and environmental levels were identified that affected evacuation. Interventions that address the barriers to evacuation may improve the full-scale evacuation of other high-rise buildings under extreme

  14. Study of a new solar adsorption refrigerator powered by a parabolic trough collector

    International Nuclear Information System (INIS)

    El Fadar, A.; Mimet, A.; Azzabakh, A.; Perez-Garcia, M.; Castaing, J.

    2009-01-01

    This paper presents the study of solar adsorption cooling machine, where the reactor is heated by a parabolic trough collector (PTC) and is coupled with a heat pipe (HP). This reactor contains a porous medium constituted of activated carbon, reacting by adsorption with ammonia. We have developed a model, based on the equilibrium equations of the refrigerant, adsorption isotherms, heat and mass transfer within the adsorbent bed and energy balance in the hybrid system components. From real climatic data, the model computes the performances of the machine. In comparison with other systems powered by flat plate or evacuated tube collectors, the predicted results, have illustrated the ability of the proposed system to achieve a high performance due to high efficiency of PTC, and high flux density of heat pipe

  15. Evacuation decision-making: process and uncertainty

    Energy Technology Data Exchange (ETDEWEB)

    Mileti, D.; Sorensen, J.; Bogard, W.

    1985-09-01

    The purpose was to describe the processes of evacuation decision-making, identify and document uncertainties in that process and discuss implications for federal assumption of liability for precautionary evacuations at nuclear facilities under the Price-Anderson Act. Four major categories of uncertainty are identified concerning the interpretation of hazard, communication problems, perceived impacts of evacuation decisions and exogenous influences. Over 40 historical accounts are reviewed and cases of these uncertainties are documented. The major findings are that all levels of government, including federal agencies experience uncertainties in some evacuation situations. Second, private sector organizations are subject to uncertainties at a variety of decision points. Third, uncertainties documented in the historical record have provided the grounds for liability although few legal actions have ensued. Finally it is concluded that if liability for evacuations is assumed by the federal government, the concept of a ''precautionary'' evacuation is not useful in establishing criteria for that assumption. 55 refs., 1 fig., 4 tabs.

  16. ARKTOS full-scale evacuation tests

    Energy Technology Data Exchange (ETDEWEB)

    Seligman, B.; Hatfield, P. [ARKTOS Developments Ltd., Surrey, BC (Canada); Bercha, F. [Bercha Group, Calgary, AB (Canada)

    2008-09-15

    The ARKTOS amphibious vehicle can be used for evacuation operations in both open water and ice conditions. It is approved as an evacuation system by various regulators, such as the United States Coast Guard, and is operational in several marine cold regions as an escape, evacuation, and rescue (EER) system. An EER research project was performed in 2006 that provided a general reliability evaluation of the ARKTOS system. However, the project did not have the benefit of detailed full-scale tests in order to validate the associated computer model in drill or non-life threatening evacuation conditions. This paper described a follow-up set of full-scale evacuation tests designed to provide more detailed information and validation data for the reliability that the computer model described in the 2006 research project. A description and photographic illustrations of the ARKTOS system were presented. The tests and subsequent analyses were described. Specifically, the paper described the observations, and presented the statistical results from the data collected, and compared observed results with predicted results of a probabilistic EER simulation computer model. Conclusions and recommendations for reliability improvements were also provided. It was concluded that under the benign conditions, the drill performance was satisfactory in all aspects, both in the evacuation activities and the rescue or de-boarding activities. 3 refs., 1 tab., 17 figs.

  17. Study of the components of evacuation times

    International Nuclear Information System (INIS)

    Mills, G.S.; Neuhauser, K.S.; Smith, J.D.

    1997-11-01

    The magnitudes of accident dose risks calculated by the RADTRAN code depend directly on the time span between an accidental release and evacuation of the affected area surrounding potential radionuclide releases. In a previous study of truck and rail transportation accidents, and other incidents requiring evacuations, a lognormal distribution of evacuation times (time span from decision to evacuate until complete) was developed, which provided a better model for this parameter than the practice of using a highly conservative value of 24 hours. However, the distribution did not account for time required for responders to arrive on the scene, to evaluate the hazards to surrounding population and to initiate an evacuation. Data from US Department of Transportation (DOT) accident statistics have been collected and their distribution functions determined. The separate distribution functions were combined into a single, comprehensive distribution which may be sampled to supply values of the RADTRAN input parameter, EVACUATION. A sample RADTRAN calculation illustrating the effect on risks of using the distribution versus the original (24 hour), conservative point-estimate are also presented

  18. Study of the components of evacuation times

    International Nuclear Information System (INIS)

    Mills, G.S.; Neuhauser, K.S.; Smith, J.D.

    1998-01-01

    The magnitudes of accident dose-risks calculated by the RADTRAN code depend directly on the time span between an accidental release and evacuation of the affected area surrounding potential radionuclide releases. In a previous study of truck and rail transportation accidents, and other incidents requiring evacuations (Mills et al., 1995) a lognormal distribution of evacuation times (time span from decision to evacuate until complete) was developed, which provided a better model for this parameter than the practice of using a highly conservative value of 24 hours. However, the distribution did not account for time required for responders to arrive on the scene, to evaluate the hazards to surrounding population and to initiate an evacuation. Data from U.S. Department of Transportation (DOT) accident statistics have been collected and their distribution functions determined. The separate distribution functions were combined into a single, comprehensive distribution which may be sampled to supply values of the RADTRAN input parameter, EVACUATION. A sample RADTRAN calculation illustrating the effect on risks of using the distribution versus the original (24 hours), conservative point-estimate are also presented. (authors)

  19. Exergy analysis of photovoltaic solar collector

    International Nuclear Information System (INIS)

    Sopian, K.; Othman, M.Y.Hj.

    1998-01-01

    The exergy analysis (availability or second law analysis) is applied to the photovoltaic thermal solar collector. Photovoltaic thermal collector is a special type of solar collector where electricity and heat are produced simultaneously. The electricity produced from the photovoltaic thermal collector is all converted into useful work. The available quantity of the heat collected can readily be determined by taking into account both the quantity (heat quantity) and quality ( a function of temperature) of the thermal energy. Therefore, using the concept of exergy allows heat produced from the thermal collector and the electricity generated from the photovoltaic cells to be compared or to be evaluated on the basis of a common measure such as the effectiveness on solar energy collection or the total amount of available energy. In this paper, the effectiveness of solar energy collection is called combined photovoltaic thermal exergy efficiency. An experimental setup of a double pas photovoltaic thermal solar collector has been deigned, fabricated and tested. (author)

  20. PV-hybrid and thermoelectric collectors

    Energy Technology Data Exchange (ETDEWEB)

    Rockendorf, G.; Sillmann, R. [Institut fuer Solarenergieforschung GmbH, Emmerthal (Germany); Podlowski, L.; Litzenburger, B. [SolarWerk GmbH, Teltow (Germany)

    1999-07-01

    Two different principles of thermoelectric cogeneration solar collectors have been realized and investigated. Concerning the first principle, the thermoelectric collector (TEC) delivers electricity indirectly by first producing heat and subsequently generating electricity by means of a thermoelectric generator. Concerning the second principle, the photovoltaic-hybrid collector (PVHC) uses photovoltaic cells, which are cooled by a liquid heat-transfer medium. The characteristics of both collector types are described. Simulation modules have been developed and implemented in TRNSYS 14.1 (1994), in order to simulate their behaviour in typical domestic hot-water systems. The discussion of the results shows that the electric output of the PV-hybrid collector is significantly higher than that of the thermoelectric collector. (author)

  1. Standardized performance tests of collectors of solar thermal energy: Prototype moderately concentrating grooved collectors

    Science.gov (United States)

    1976-01-01

    Prototypes of moderately concentrating grooved collectors were tested with a solar simulator for varying inlet temperature, flux level, and incident angle. Collector performance is correlated in terms of inlet temperature and flux level.

  2. Depressed collectors for millimeter wave gyrotrons

    International Nuclear Information System (INIS)

    Singh, A.; Granatstein, V.L.

    1992-01-01

    The main issues relating to design of depressed collectors for millimeter wave gyrotrons are discussed. A flow diagram is presented and the interlinking steps are outlined. Design studies are given for two kinds of gyrotrons on which severe constraints on the maximum radii of the collectors had been imposed; namely, for a cavity type and a quasi-optical gyrotron. A collector efficiency of the order of 70 percent is shown to be feasible for either case using careful tailoring of magnetic field profiles. A code has been developed to assist in doing this. A general approach toward initial placement of collectors has been indicated

  3. Rising hopes for vacuum tube collectors

    Energy Technology Data Exchange (ETDEWEB)

    Godolphin, D.

    1982-06-01

    The performance, feasibility and use of vacuum tube solar collectors for domestic hot water (DHW) systems are discussed. An introduction to the design of vacuum tube collectors is presented and comparisons are made with flat plate collectors in terms of effectiveness in DHW applications and cost. The use of vacuum tube collectors is well established for high temperature use such as process heat and absorption cooling applications; there is considerable debate concerning their use in DHW and these arguments are presented. It is pointed out that the accepted standardized comparison test (ASHRAE 93-77) is apparently biased towards the flat plate collectors in direct comparisons of collector efficiencies. Recent developments among manufacturers with regard to vacuum tube collectors and their thinking (pro and con) are discussed in some detail. Breakage and other problems are pointed out although advocates look ahead to lower costs, higher efficiencies, and broader markets (particularly in DHW). It is concluded by some that flat plate collector technology has reached its peak and that vacuum tube collectors will be very prominent in the future. (MJJ)

  4. Modified tubularized incised plate urethroplasty

    Directory of Open Access Journals (Sweden)

    Shivaji Mane

    2013-01-01

    Full Text Available Aim: To share our experience of doing tubularized incised plate urethroplasty with modifications. Materials and Methods: This is a single surgeon personal series from 2004 to 2009. One hundred patients of distal hypospadias were subjected for Snodgrass urethroplasty with preputioplasty. The age range was 1 to 5 year with mean age of 2.7 years. Selection criteria were good urethral plate, without chordee and torsion needing complete degloving. Main technical modification from original Snodgrass procedure was spongioplasty, preputioplasty, and dorsal slit when inability to retract prepuce during surgery. Results: Average follow-up period is 23 months. Seven (7% patients developed fistula and one patient had complete preputial dehiscence. Phimosis developed in three (3% patients and required circumcision. Dorsal slit was required in seven patients. One patient developed meatal stenosis in postoperative period. All other patients are passing single urinary stream and have cosmesis that is acceptable. Conclusions: Modified tubularized incised plate urethroplasty with preputioplasty effectively gives cosmetically normal looking penis with low complications.

  5. Pedestrian evacuation modeling to reduce vehicle use for distant tsunami evacuations in Hawaiʻi

    Science.gov (United States)

    Wood, Nathan J.; Jones, Jamie; Peters, Jeff; Richards, Kevin

    2018-01-01

    Tsunami waves that arrive hours after generation elsewhere pose logistical challenges to emergency managers due to the perceived abundance of time and inclination of evacuees to use vehicles. We use coastal communities on the island of Oʻahu (Hawaiʻi, USA) to demonstrate regional evacuation modeling that can identify where successful pedestrian-based evacuations are plausible and where vehicle use could be discouraged. The island of Oʻahu has two tsunami-evacuation zones (standard and extreme), which provides the opportunity to examine if recommended travel modes vary based on zone. Geospatial path distance models are applied to estimate population exposure as a function of pedestrian travel time and speed out of evacuation zones. The use of the extreme zone triples the number of residents, employees, and facilities serving at-risk populations that would be encouraged to evacuate and slightly reduces the percentage of residents (98–76%) that could evacuate in less than 15 min at a plausible speed (with similar percentages for employees). Areas with lengthy evacuations are concentrated in the North Shore region for the standard zone but found all around the Oʻahu coastline for the extreme zone. The use of the extreme zone results in a 26% increase in the number of hotel visitors that would be encouraged to evacuate, and a 76% increase in the number of them that may require more than 15 min. Modeling can identify where pedestrian evacuations are plausible; however, there are logistical and behavioral issues that warrant attention before localized evacuation procedures may be realistic.

  6. A method of emotion contagion for crowd evacuation

    Science.gov (United States)

    Cao, Mengxiao; Zhang, Guijuan; Wang, Mengsi; Lu, Dianjie; Liu, Hong

    2017-10-01

    The current evacuation model does not consider the impact of emotion and personality on crowd evacuation. Thus, there is large difference between evacuation results and the real-life behavior of the crowd. In order to generate more realistic crowd evacuation results, we present a method of emotion contagion for crowd evacuation. First, we combine OCEAN (Openness, Extroversion, Agreeableness, Neuroticism, Conscientiousness) model and SIS (Susceptible Infected Susceptible) model to construct the P-SIS (Personalized SIS) emotional contagion model. The P-SIS model shows the diversity of individuals in crowd effectively. Second, we couple the P-SIS model with the social force model to simulate emotional contagion on crowd evacuation. Finally, the photo-realistic rendering method is employed to obtain the animation of crowd evacuation. Experimental results show that our method can simulate crowd evacuation realistically and has guiding significance for crowd evacuation in the emergency circumstances.

  7. Tubular lining material for pipelines having bends

    Energy Technology Data Exchange (ETDEWEB)

    Moringa, A.; Sakaguchi, Y.; Hyodo, M.; Yagi, I.

    1987-03-24

    A tubular lining material for pipelines having bends or curved portions comprises a tubular textile jacket made of warps and wefts woven in a tubular form overlaid with a coating of a flexible synthetic resin. It is applicable onto the inner surface of a pipeline having bends or curved portions in such manner that the tubular lining material with a binder onto the inner surface thereof is inserted into the pipeline and allowed to advance within the pipeline, with or without the aid of a leading rope-like elongated element, while turning the tubular lining material inside out under fluid pressure. In this manner the tubular lining material is applied onto the inner surface of the pipeline with the binder being interposed between the pipeline and the tubular lining material. The lining material is characterized in that a part of all of the warps are comprised of an elastic yarn around which, over the full length thereof, a synthetic fiber yarn or yarns have been left-and/or right-handedly coiled. This tubular lining material is particularly suitable for lining a pipeline having an inner diameter of 25-200 mm and a plurality of bends, such as gas service pipelines or house pipelines, without occurrence of wrinkles in the lining material in a bend.

  8. Experimental investigation of the higher coefficient of thermal performance for water-in-glass evacuated tube solar water heaters in China

    International Nuclear Information System (INIS)

    Zhang, Xinyu; You, Shijun; Xu, Wei; Wang, Min; He, Tao; Zheng, Xuejing

    2014-01-01

    Highlights: • The energy grades system for solar water heater (SWH) in China was introduced. • Heat loss and capacity of heat collection mainly affected SWH thermal performance. • Optimum ratio of tank volume to collector area for solar water heater is 57 to 72 L/m 2 . • The recommendation polyurethane insulation layer should be around 50 mm thick. • SWH with shorter tube has a better thermal performance. - Abstract: Solar water heaters (SWHs), now widely used in China, represent an environmentally friendly way to heat water. We tested the performance of more than 1000 water-in-glass evacuated tube SWHs according to Chinese standards and found that the heat loss from the storage tank and capacity of the solar collector affected their thermal performance. The optimum parameters to maximize the performance of water-in-glass evacuated tube SWHs included a ratio of tank volume to collector area of 57–72 L/m 2 , which should give a system efficiency of 0.49–0.57, meaning that the temperature of water in the tank will exceed 45 °C after one day of heat collection. In addition, the polyurethane insulation layer should be around 50 mm thick with a free foaming density of about 35 kg/m 3 , and the evacuated tube should be short. The tilt angle did not affect the performance of the SWHs. These results should aid in the design of highly efficient SWHs

  9. Tubular inverse opal scaffolds for biomimetic vessels

    Science.gov (United States)

    Zhao, Ze; Wang, Jie; Lu, Jie; Yu, Yunru; Fu, Fanfan; Wang, Huan; Liu, Yuxiao; Zhao, Yuanjin; Gu, Zhongze

    2016-07-01

    There is a clinical need for tissue-engineered blood vessels that can be used to replace or bypass damaged arteries. The success of such grafts depends strongly on their ability to mimic native arteries; however, currently available artificial vessels are restricted by their complex processing, controversial integrity, or uncontrollable cell location and orientation. Here, we present new tubular scaffolds with specific surface microstructures for structural vessel mimicry. The tubular scaffolds are fabricated by rotationally expanding three-dimensional tubular inverse opals that are replicated from colloidal crystal templates in capillaries. Because of the ordered porous structure of the inverse opals, the expanded tubular scaffolds are imparted with circumferentially oriented elliptical pattern microstructures on their surfaces. It is demonstrated that these tailored tubular scaffolds can effectively make endothelial cells to form an integrated hollow tubular structure on their inner surface and induce smooth muscle cells to form a circumferential orientation on their outer surface. These features of our tubular scaffolds make them highly promising for the construction of biomimetic blood vessels.There is a clinical need for tissue-engineered blood vessels that can be used to replace or bypass damaged arteries. The success of such grafts depends strongly on their ability to mimic native arteries; however, currently available artificial vessels are restricted by their complex processing, controversial integrity, or uncontrollable cell location and orientation. Here, we present new tubular scaffolds with specific surface microstructures for structural vessel mimicry. The tubular scaffolds are fabricated by rotationally expanding three-dimensional tubular inverse opals that are replicated from colloidal crystal templates in capillaries. Because of the ordered porous structure of the inverse opals, the expanded tubular scaffolds are imparted with circumferentially

  10. Foldable Frame Supporting Electromagnetic Radiation Collectors

    DEFF Research Database (Denmark)

    2011-01-01

    The present invention relates to flexible frames supporting electromagnetic radiation collectors, such as antennas, antenna reflectors, deflectors or solar collectors, for celestial or terrestrial applications, which can be folded to be stored and/or transported. The method for stowing deforms...

  11. EFFECT OF BLENDING VARIOUS COLLECTORS AT BULK ...

    African Journals Online (AJOL)

    Nkana Concentrator under the ownership of the then Zambia Consolidated Copper Mines Ltd (ZCCM) had been using Sodium Ethyl Xanthate (SEX) mainly as a collector, but with the coming of new Mopani Copper Mines Plc (M.C.M), it was felt that there was a need to test alternative collectors in an attempt to improve the ...

  12. Flat-plate solar collector - installation package

    Science.gov (United States)

    1978-01-01

    Package includes installation, operation and maintenance manual for collector, analysis of safety hazards, special handling instructions, materials list, installation drawings, and warranty and certification statement. Manual includes instructions for roof preparation and for preparing collector for installation. Several pages are devoted to major and minor repairs.

  13. Performance of an absorbing concentrating solar collectors

    International Nuclear Information System (INIS)

    Imadojemu, H.

    1990-01-01

    This paper reports on a comparison of the efficiency of an absorbing fluid parabolic trough concentrating solar collector and a traditional concentrating collector that was made. In the absorbing fluid collector, black liquid flows through a glass tube absorber while the same black liquid flows through a selective black coated copper tube absorber while the same black fluid flows through a selective black coated copper tube absorber in the traditional collector. After a careful study of the properties of available black liquids, a mixture of water and black ink was chosen as the black absorbing medium or transfer fluid. In the black liquid glass collector there is a slightly improved efficiency based on beam radiation as a result of the direct absorption process and an increase in the effective transmittance absorptance. At worst the efficiency of this collector equals that of the traditional concentrating collector when the efficiency is based on total radiation. The collector's reflecting surfaces were made of aluminum sheet, parabolic line focus and with cylindrical receivers. The ease of manufacture and reduced cost per unit energy collected, in addition to the clean and pollution free mode of energy conversion, makes it very attractive

  14. Cheap effective thermal solar-energy collectors

    Energy Technology Data Exchange (ETDEWEB)

    Highgate, D.J.; Probert, S.D. [Cranfield University, Bedford (United Kingdom). Dept. of Applied Energy

    1996-04-01

    A light-weight flexible solar-collector, with a wavelength-selective absorption surface and an insolation-transparent thermal-insulation protecter for its aperture, was built and tested. Its cheapness and high performance, relative to a conventional flat-plate solar-collector, provide a prima-facie case for the more widespread adoption of its design. (author)

  15. Combined solar collector and energy storage system

    Science.gov (United States)

    Jensen, R. N. (Inventor)

    1980-01-01

    A combined solar energy collector, fluid chiller and energy storage system is disclosed. A movable interior insulated panel in a storage tank is positionable flush against the storage tank wall to insulate the tank for energy storage. The movable interior insulated panel is alternately positionable to form a solar collector or fluid chiller through which the fluid flows by natural circulation.

  16. OUT Success Stories: Transpired Solar Collectors

    International Nuclear Information System (INIS)

    Clyne, R.

    2000-01-01

    Transpired solar collectors are a reliable, low-cost technology for preheating building ventilation air. With simple payback periods ranging from 3 to 12 years and an estimated 30-year life span, transpired collector systems offer building owners substantial cost savings

  17. Survey of active solar thermal collectors, industry and markets in Canada : final report

    International Nuclear Information System (INIS)

    2005-08-01

    A survey of the solar thermal industry in Canada was presented. The aim of the survey was to determine the size of the Canadian solar thermal industry and market. Data were used to derive thermal energy output as well as avoided greenhouse gas (GHG) emissions from solar thermal systems. The questionnaire was distributed to 268 representatives. Results revealed annual sales of 24.2, 26.4 and 37.5 MW TH in 2002, 2003, and 2004 respectively, which represented over 50 per cent growth in the operating base during the 3 year survey period. Sales of all collector types grew substantially during the 3 year period, and survey respondents anticipated 20 per cent growth in both 2005 and 2006. Approximately 10 per cent of all sales were exported during 2002-2004. Unglazed liquid collectors constituted the majority of collector types sold in Canada, almost all of which were sold into the residential sector for swimming pool heating. The majority of air collectors were sold into the industrial/commercial and institutional (I/CI) sectors for use in space heating. Sales of liquid glazed and evacuated tube collectors were split between the residential and I/CI sectors. Residential sales were primarily for domestic water heating. In 2004, 23 per cent of sales in the residential sector were for combination domestic hot water and space heating applications, an indication of strong growth. Results of the survey indicated that the solar thermal market in Quebec differed from other regions, with more than double the annual per capita revenue of any other region as a result of greater market penetration of unglazed air collectors. Calculations of the GHG emissions avoided due to active solar thermal systems were made based on historical estimates of solar thermal installations. A model was developed to calculate an operating base by collector type from 1979 to the present. The model showed that many of the systems installed during the 1980s were decommissioned during the 1990s, and that

  18. Survey of active solar thermal collectors, industry and markets in Canada : final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-08-01

    A survey of the solar thermal industry in Canada was presented. The aim of the survey was to determine the size of the Canadian solar thermal industry and market. Data were used to derive thermal energy output as well as avoided greenhouse gas (GHG) emissions from solar thermal systems. The questionnaire was distributed to 268 representatives. Results revealed annual sales of 24.2, 26.4 and 37.5 MW{sub TH} in 2002, 2003, and 2004 respectively, which represented over 50 per cent growth in the operating base during the 3 year survey period. Sales of all collector types grew substantially during the 3 year period, and survey respondents anticipated 20 per cent growth in both 2005 and 2006. Approximately 10 per cent of all sales were exported during 2002-2004. Unglazed liquid collectors constituted the majority of collector types sold in Canada, almost all of which were sold into the residential sector for swimming pool heating. The majority of air collectors were sold into the industrial/commercial and institutional (I/CI) sectors for use in space heating. Sales of liquid glazed and evacuated tube collectors were split between the residential and I/CI sectors. Residential sales were primarily for domestic water heating. In 2004, 23 per cent of sales in the residential sector were for combination domestic hot water and space heating applications, an indication of strong growth. Results of the survey indicated that the solar thermal market in Quebec differed from other regions, with more than double the annual per capita revenue of any other region as a result of greater market penetration of unglazed air collectors. Calculations of the GHG emissions avoided due to active solar thermal systems were made based on historical estimates of solar thermal installations. A model was developed to calculate an operating base by collector type from 1979 to the present. The model showed that many of the systems installed during the 1980s were decommissioned during the 1990s, and

  19. 78 FR 14361 - U.S. Steel Tubular Products, Inc., Mckeesport Tubular Operations Division, Subsidiary of United...

    Science.gov (United States)

    2013-03-05

    ... Products, Inc., Mckeesport Tubular Operations Division, Subsidiary of United States Steel Corporation, Mckeesport, PA; Notice of Initiation of Investigation To Terminate Certification of Eligibility Pursuant to... Tubular Products, McKeesport Tubular Operations Division, Subsidiary of United States Steel Corporation...

  20. The Thermal Collector With Varied Glass Covers

    International Nuclear Information System (INIS)

    Luminosu, I.; Pop, N.

    2010-01-01

    The thermal collector with varied glass covers represents an innovation realized in order to build a collector able to reach the desired temperature by collecting the solar radiation from the smallest surface, with the highest efficiency. In the case of the thermal collector with variable cover glasses, the number of the glass plates covering the absorber increases together with the length of the circulation pipe for the working fluid. The thermal collector with varied glass covers compared to the conventional collector better meet user requirements because: for the same temperature increase, has the collecting area smaller; for the same collection area, realizes the highest temperature increase and has the highest efficiency. This works is addressed to researchers in the solar energy and to engineers responsible with air-conditioning systems design or industrial and agricultural products drying.

  1. Comparison of calculation and simulation of evacuation in real buildings

    Science.gov (United States)

    Szénay, Martin; Lopušniak, Martin

    2018-03-01

    Each building must meet requirements for safe evacuation in order to prevent casualties. Therefore methods for evaluation of evacuation are used when designing buildings. In the paper, calculation methods were tested on three real buildings. The testing used methods of evacuation time calculation pursuant to Slovak standards and evacuation time calculation using the buildingExodus simulation software. If calculation methods have been suitably selected taking into account the nature of evacuation and at the same time if correct values of parameters were entered, we will be able to obtain almost identical times of evacuation in comparison with real results obtained from simulation. The difference can range from 1% to 27%.

  2. Evacuation of the NET vacuum chamber

    International Nuclear Information System (INIS)

    Muller, R.A.

    1987-01-01

    Parametric calculations of the evacuation process were carried out for the NET-vacuum chamber involving two blanket designs. The results show that with an acceptable vacuum pumping capacity the required start vacuum conditions can be realized within reasonable time. The two blanket concepts do not differ remarkably in their evacuation behaviour. The remaining large pressure differences between the different locations of the vacuum chamber can be reduced if approximately 30% of the total gas flow is extracted from the heads of the blanket replacement ports

  3. Evacuation of the NET vacuum chamber

    International Nuclear Information System (INIS)

    Mueller, R.

    1986-01-01

    Parametric calculations of the evacuation process were carried out for the NET-vacuum chamber involving two blanket designs. The results show that with an acceptable vacuum pumping capacity the required start vacuum conditions can be realized within reasonable time. The two blanket concepts do not differ remarkably in their evacuation behaviour. The remaining large pressure differences between the different locations of the vacuum chamber can be reduced if approximately 30% of the total gas flow is extracted from the heads of the blanket replacement ports. (author)

  4. COMPARATIVE FIELD EXPERIMENTAL INVESTIGATIONS OF DIFFERENT FLAT PLATE SOLAR COLLECTORS

    Directory of Open Access Journals (Sweden)

    Guangming Chen

    2015-12-01

    Full Text Available Full-scale traditional metal solar collectors and solar collector specimens fabricated from polymeric materials were investigated in the present study. A polymeric collector is 67.8% lighter than a traditional metal solar collector, and a metal solar collector with transparent plastic covering is 40.3% lighter than a traditional metal solar collector. Honeycomb multichannel plates made from polycarbonate were chosen to create a polymeric solar collector. A test rig for the natural circulation of the working fluid in a solar collector was built for a comparative experimental investigation of various solar collectors operating at ambient conditions. It was shown experimentally that the efficiency of a polymeric collector is 8–15% lower than the efficiency of a traditional collector.

  5. Tubular bioreactor and its application; Tubular bioreactor to sono tekiyo

    Energy Technology Data Exchange (ETDEWEB)

    Endo, I.; Nagamune, T. [The University of Tokyo, Tokyo (Japan). Faculty of Engineering; Yuki, K. [Nikka Whisky Distilling Co. Ltd. Tokyo (Japan); Inaba, H. [Sumitomo Heavy Industries, Ltd., Tokyo (Japan)

    1994-09-05

    The loop type tubular bioreactor (TBR) was developed where biocatalysts are trapped in the reactor by membrane module. A UF membrane or MF membrane and crossflow filtration were adopted for the membrane module, and the reactor loop was composed of four membrane modules. The reactor was operated at 2-4 m/s in membrane surface velocity and 300-400 kPa in filtration pressure. As the result of the high-density culture of lactic acid bacteria and yeast, a biomass concentration was more than 10 times that in batch culture, suggesting the remarkable enhancement of a production efficiency. As the result of the continuous fermentation of cider, the fast fermentation more than 60 times that in conventional ones was obtained together with the same quality as conventional ones. Such a fast fermentation was probably achieved by yeast suspended in the fermenter of TBR, by yeast hardly affected physico-chemically as compared with immobilized reactors, and by small effect of mass transfer on reaction systems. 4 refs., 6 figs.

  6. Pedestrian collective motion in competitive room evacuation.

    Science.gov (United States)

    Garcimartín, A; Pastor, J M; Martín-Gómez, C; Parisi, D; Zuriguel, I

    2017-09-07

    When a sizable number of people evacuate a room, if the door is not large enough, an accumulation of pedestrians in front of the exit may take place. This is the cause of emerging collective phenomena where the density is believed to be the key variable determining the pedestrian dynamics. Here, we show that when sustained contact among the individuals exists, density is not enough to describe the evacuation, and propose that at least another variable -such as the kinetic stress- is required. We recorded evacuation drills with different degrees of competitiveness where the individuals are allowed to moderately push each other in their way out. We obtain the density, velocity and kinetic stress fields over time, showing that competitiveness strongly affects them and evidencing patterns which have been never observed in previous (low pressure) evacuation experiments. For the highest competitiveness scenario, we detect the development of sudden collective motions. These movements are related to a notable increase of the kinetic stress and a reduction of the velocity towards the door, but do not depend on the density.

  7. Uncertainty in a spatial evacuation model

    Science.gov (United States)

    Mohd Ibrahim, Azhar; Venkat, Ibrahim; Wilde, Philippe De

    2017-08-01

    Pedestrian movements in crowd motion can be perceived in terms of agents who basically exhibit patient or impatient behavior. We model crowd motion subject to exit congestion under uncertainty conditions in a continuous space and compare the proposed model via simulations with the classical social force model. During a typical emergency evacuation scenario, agents might not be able to perceive with certainty the strategies of opponents (other agents) owing to the dynamic changes entailed by the neighborhood of opponents. In such uncertain scenarios, agents will try to update their strategy based on their own rules or their intrinsic behavior. We study risk seeking, risk averse and risk neutral behaviors of such agents via certain game theory notions. We found that risk averse agents tend to achieve faster evacuation time whenever the time delay in conflicts appears to be longer. The results of our simulations also comply with previous work and conform to the fact that evacuation time of agents becomes shorter once mutual cooperation among agents is achieved. Although the impatient strategy appears to be the rational strategy that might lead to faster evacuation times, our study scientifically shows that the more the agents are impatient, the slower is the egress time.

  8. Evacuation of bedridden occupants : experimental research outcomes

    NARCIS (Netherlands)

    Strating, N.; van Herpen, R.; Zeiler, W.

    2017-01-01

    Bedridden building occupants in hospitals and nursing homes who are not able to rescue themselves in case of a fire emergency require assistance during an evacuation. A building emergency team usually fulfils this function and will have to remove the occupants from the room. The speed at which such

  9. Evacuation Risks: a tentative approach for quantification

    International Nuclear Information System (INIS)

    Bastien, M.C.; Dumas, M.; Laporte, J; Parmentier, N.

    1985-01-01

    This study tries to assess the risk of deaths and injuries from motor vehicle accidents associated with an evacuation of population groups in case of nuclear plant accidents. The risk per person-km is evaluated using: (a) data from previous evacuation: information from Soufriere evacuation (Guadeloupe Island 1976) and Mississauga (1979), added to Hans and Sell's data: no road accident occurred for a sample of 1,500,000 persons; (b) national recording system for motor vehicle accident: the rates of 2.2 10 -8 deaths per person-km and 32 10 -8 injuries per person-km is calculated as an average. These last rates in France overestimate the number of casualties. A reasonable hypothesis is to assume that the probability of road accident occurrence follows a Poisson distribution, as these events are independent and unfrequent, as no accident was observed in a sample of 1,500,000 persons the probability is between 0 and an upper value of 0.24 10 -8 deaths per person-km and 3.29 10 -8 injuries per person-km. The average and maximum population involved within different radii around French and U.S. Nuclear power sites are taken as a sample size in order to study the total risk of deaths and injuries in the hypothesis of an evacuation being necessary to protect the populations

  10. Aeromedical Evacuation: Validating Civil Reserve Air Fleet

    Science.gov (United States)

    2009-02-25

    flight nurses and three medical technicians) is added for AE missions. The aeromedical evacuation crew (AEC) may be pared and tailored as required in... Biosecurity and Bioterrorism: Biodefense Strategy, Practice and Science, Volume 5, Number 4, 2007: 319-325. 34 IAT.R 0554 General Accounting Office

  11. An adaptive simulation tool for evacuation scenarios

    NARCIS (Netherlands)

    Formolo, Daniel; van der Wal, C. Natalie

    2017-01-01

    Building useful and efficient models and tools for a varied audience, such as evacuation simulators for scientists, engineers and crisis managers, can be tricky. Even good models can fail in providing information when the user’s tools for the model are scarce of resources. The aim of this work is to

  12. Evacuating the Area of a Hurricane

    Centers for Disease Control (CDC) Podcasts

    2006-08-10

    If a hurricane warning is issued for your area, or authorities tell you to evacuate, take only essential items. If you have time, turn off gas, electricity, and water and disconnect appliances.  Created: 8/10/2006 by Emergency Communications System.   Date Released: 10/10/2007.

  13. Single-stage depressed collectors for gyrotrons

    International Nuclear Information System (INIS)

    Piosczyk, B.; Iatrou, C.T.; Dammertz, G.; Thumm, M.; Univ. Karlsruhe

    1996-01-01

    Two 140 GHz gyrotrons with a single-step depressed collector have been operated. The different position of the isolating collector gap in the stray magnetic field causes the electron motion in the retarding region to be in one case adiabatic and in the other case nonadiabatic. The kind of motion within the retarding field influences strongly the behavior of the gyrotron with a depressed collector. In the case of nonadiabatic motion a significant amount of transverse momentum is given to the electrons reflected at the collector potential. This causes the reflected electrons to be trapped between the magnetic mirror and the collector. The electrons escape from the trap by diffusion across the magnetic field to the body of the tube thus contributing to the body current. Despite the high body current there is no observable influence of the collector voltage on the RF output power. In the case of adiabatic motion the reflected electrons do not gain a sufficient amount of transverse momentum to be trapped by the magnetic mirror. They pass the cavity toward the gun and they are trapped between the negative gun potential and the collector. The interaction with the RF field by electrons traveling through the cavity enhances the diffusion in the velocity space thus enabling the trapped electrons to overcome the potential barrier and escape toward the collector. Therefore the body current stays at low values since in this case the reflected electrons do not contribute to it. However, at higher collector voltages a reduction of RF power occurred and some noise in the electron beam was observed. The main motivation for the development of gyrotrons in the frequency range above 100 GHz with power levels in excess of several hundreds kW per tube, is the application in magnetic fusion devices for plasma heating and for electron current drive

  14. FIRE EVACUATION FROM HIGH-RISE BUILDINGS

    Directory of Open Access Journals (Sweden)

    Korol'chenko Aleksandr Yakovlevich

    2012-10-01

    Full Text Available The authors argue that no collapse of structures is likely in the event of a fire emergency in multistoried buildings, rather, other fire-related factors may endanger the lives of people inside high-rise buildings exposed to the fire emergency, including open fire, sparks, high ambient temperature, smoke and toxic combustion products, reduced concentration of oxygen, and combined influence of various factors. In case of fire, the temperature inside buildings reaches 1100 °С. It exceeds the temperature of the ambient air acceptable for humans by far (70 °С. The experiments demonstrate that combustion products contain hundreds of toxic chemical compounds. The most hazardous of them include carbon oxide, carbon dioxide, chloride and cyanic hydrogen, aldehydes and acrolein. The author provides the pattern of their influence on the human body. The smoke consists of unburned particles of carbon and aerosols. The size of particles fluctuates within 0.05-50 MMK. Smoke produces a physiological and psychological impact on human beings. It has been proven that dangerous fire factors emerge within the first five to ten minutes of the emergency situation. Evacuation is the principal method of safety assurance. However, the velocity of propagation of smoke and heat is so high that even if the fire prevention system is in operation, people may be blocked both on the floors that are exposed to the fire and those that escape its propagation. New evacuation and rescue methods are recommended by the author. Various ways and methods of use of life-saving facilities are also provided. Safe evacuation is feasible from buildings where the number of stories does not exceed 10- 12. During evacuation, high density human streams are formed inside buildings, therefore, the period of stay in a burning building is increased. The calculations have proven that a two-minute delay of evacuation converts into a safe evacuation of only 13-15% of people. Low reliability of

  15. Information of the Home Office for the planning of evacuations

    International Nuclear Information System (INIS)

    1983-01-01

    This information contains the legal basis, scope and jurisdiction for evacuations in cases of accident. The general evacuation plan must schedule the following: private and public transport, information equipment, supply and care services, evacuation routes and traffic control checkpoints, etc. Particular evacuation plans must be established e.g. for nuclear plants and barrages. The planning is based on a survey of measures represented by a flowchart or a checklist. (HSCH) [de

  16. Engineering design of 500KW CW collector

    International Nuclear Information System (INIS)

    Kumar, Ramesh; Mishra, Deepak; Prasad, M.; Hannuarakar, P.R.

    2006-01-01

    An electron beam collector for 500kW beam power has been designed to test the electron gun. The gun is designed for 250kW, 350MHz CW Klystron with 50% efficiency. This will also help in preliminary studies related to final collector design for Klystron. This paper presents the design parameters, thermal analysis and mechanical features of the design. Electron trajectory on inside wall of the collector is determined with EGUN and computational flow dynamics simulation was done on ANSYS for cooling requirements. (author)

  17. Next Generation Solar Collectors for CSP

    Energy Technology Data Exchange (ETDEWEB)

    Molnar, Attila [3M Company, St. Paul, MN (United States); Charles, Ruth [3M Company, St. Paul, MN (United States)

    2014-07-31

    The intent of “Next Generation Solar Collectors for CSP” program was to develop key technology elements for collectors in Phase 1 (Budget Period 1), design these elements in Phase 2 (Budget Period 2) and to deploy and test the final collector in Phase 3 (Budget Period 3). 3M and DOE mutually agreed to terminate the program at the end of Budget Period 1, primarily due to timeline issues. However, significant advancements were achieved in developing a next generation reflective material and panel that has the potential to significantly improve the efficiency of CSP systems.

  18. Aircraft industry workers in evacuation: conditions of life of evacuated plants' workers in 1941-1945

    Directory of Open Access Journals (Sweden)

    Михаил Юрьевич Мухин

    2010-09-01

    Full Text Available The article is devoted to the work of the factories in 1941-1945 in the evacuation. The author analyzes the living conditions of workers in evacuated aviation plants, their daily life, maintenance, etc. The author concludes that in the early years of the War the conditions of life of the aviation industry's workers were very difficult, and the welfare and financial situation improved in 1944, the sure sign of fracture in the Second world war.

  19. 21 CFR 888.4220 - Cement monomer vapor evacuator.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cement monomer vapor evacuator. 888.4220 Section... (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Surgical Devices § 888.4220 Cement monomer vapor evacuator. (a) Identification. A cement monomer vapor evacuator is a device intended for use during surgery to contain or remove...

  20. 21 CFR 876.4370 - Gastroenterology-urology evacuator.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Gastroenterology-urology evacuator. 876.4370... (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Surgical Devices § 876.4370 Gastroenterology-urology evacuator. (a) Identification. A gastroenterology-urology evacuator is a device used to remove...

  1. Improved Large Aperture Collector Manufacturing

    Energy Technology Data Exchange (ETDEWEB)

    O' Rourke, Deven [Abengoa Solar LLC, Lakewood, CO (United States); Farr, Adrian [Abengoa Solar LLC, Lakewood, CO (United States)

    2015-12-01

    The parabolic trough is the most established CSP technology and carries a long history of design experimentation dating back to the 1970’s. This has led to relatively standardized collector architectures, a maturing global supply chain, and a fairly uniform cost reduction strategy. Abengoa has deployed more than 1,500MWe of CSP troughs across several countries and has built and tested full-scale prototypes of many R&D concepts. The latest trough R&D efforts involved efforts to internalize non-CSP industry experience including a preliminary DFMA principles review done with Boothroyd Dewhurst, a construction literature review by the Arizona State University School of Construction Management, and two more focused manufacturing engineering subcontracts done by Ricardo Inc. and the nonprofit Edison Welding Institute. The first two studies highlighted strong opportunities in lowering part count, standardizing components and fasteners, developing modular designs to support prefabrication and automation, and devising simple, error-proof manual assembly methods. These principles have delivered major new cost savings in otherwise “mature” products in analogous industries like automotive, truck trailer manufacture, metal building fabrication, and shipbuilding. For this reason, they were core in the design development of the SpaceTube® collector, and arguably key to its early successes. The latter two studies were applied specifically to the first-generation SpaceTube® design and were important in setting the direction of the present SolarMat project. These studies developed a methodology to analyze the costs of manufacture and assembly, and identify new tooling concepts for more efficient manufacture. Among the main opportunities identified in these studies were the automated mirror arm manufacturing concept and the need for a less infrastructure-intensive assembly line, both of which now form central pillars of the SolarMat project strategy. These new designs will be

  2. Proximal tubular hypertrophy and enlarged glomerular and proximal tubular urinary space in obese subjects with proteinuria.

    Directory of Open Access Journals (Sweden)

    Ana Tobar

    Full Text Available BACKGROUND: Obesity is associated with glomerular hyperfiltration, increased proximal tubular sodium reabsorption, glomerular enlargement and renal hypertrophy. A single experimental study reported an increased glomerular urinary space in obese dogs. Whether proximal tubular volume is increased in obese subjects and whether their glomerular and tubular urinary spaces are enlarged is unknown. OBJECTIVE: To determine whether proximal tubules and glomerular and tubular urinary space are enlarged in obese subjects with proteinuria and glomerular hyperfiltration. METHODS: Kidney biopsies from 11 non-diabetic obese with proteinuria and 14 non-diabetic lean patients with a creatinine clearance above 50 ml/min and with mild or no interstitial fibrosis were retrospectively analyzed using morphometric methods. The cross-sectional area of the proximal tubular epithelium and lumen, the volume of the glomerular tuft and of Bowman's space and the nuclei number per tubular profile were estimated. RESULTS: Creatinine clearance was higher in the obese than in the lean group (P=0.03. Proteinuria was similarly increased in both groups. Compared to the lean group, the obese group displayed a 104% higher glomerular tuft volume (P=0.001, a 94% higher Bowman's space volume (P=0.003, a 33% higher cross-sectional area of the proximal tubular epithelium (P=0.02 and a 54% higher cross-sectional area of the proximal tubular lumen (P=0.01. The nuclei number per proximal tubular profile was similar in both groups, suggesting that the increase in tubular volume is due to hypertrophy and not to hyperplasia. CONCLUSIONS: Obesity-related glomerular hyperfiltration is associated with proximal tubular epithelial hypertrophy and increased glomerular and tubular urinary space volume in subjects with proteinuria. The expanded glomerular and urinary space is probably a direct consequence of glomerular hyperfiltration. These effects may be involved in the pathogenesis of obesity

  3. Iatrogenic Digital Compromise with Tubular Dressings

    Directory of Open Access Journals (Sweden)

    Corre, Kenneth A

    2009-08-01

    Full Text Available Objective: This case report describes a digit amputation resulting from an improperly applied tubular dressing. The safe application of digital tubular dressings, and the rationale behind it, is detailed to raise emergency physician (EP awareness.Methods: We present a case report of a recent iatrogenic-induced digit ischemia caused by improperly applied tube gauze. We review the literature on the subject and the likely sources of poor outcomes presented. The proper application of tubular gauze dressings is then outlined.Conclusion: EPs and emergency department personnel must be educated on the safe application of tubular gauze dressings to avoid dire outcomes associated with improper applications.[WestJEM. 2009;10:190-192.

  4. Renal Tubular Function in Systemic Lupus Erythematosus*

    African Journals Online (AJOL)

    immune' diseases such as. Sjogren's syndrome,'" systemic lupus erythematosus. (SLE),3 alveolitis' and chronic active hepatitis.' The reported abnormalities of renal tubular function include impairment of acid excretion and urinary concentration.

  5. A neglected case of Renal Tubular Acidosis

    International Nuclear Information System (INIS)

    Derakhshan, A.; Basiratnia, M.; Fallahzadeh, M.H.; Al-Hashemi, G.H.

    2007-01-01

    In this report, we present a case of a child with distal renal tubular acidosis, severe failure to thrive and profound rickets, who was only 7.8 Kg when presented at 6 years of age. His response to treatment and his follow up for four years is discussed. Although failure to thrive is a common finding in renal tubular acidosis but the physical and x-ray findings in our case were unique. (author)

  6. Movable air solar collector and its efficiency

    International Nuclear Information System (INIS)

    Lauva, A.; Aboltinš, A.; Palabinskis, J.; Karpova Sadigova, N.

    2008-01-01

    Implementing the guidelines of the Latvian National Programme for Energy in the field of alternative energy, intensive research shall be carried on regarding the use of solar energy, as it can be successfully used not only for the purposes of water heating and production of electrical energy, but also for air warming. The amount of heat necessary for the drying of rough forage and grain drying by active aeration in June, July and August can be obtained using solar radiation. The Latvian Guidelines for the Energy Development 2006-2016 state that the solar radiance in Latvia is of quite low intensity. The total amount of solar energy is 1109 kWh m -2 per year. The period of usage of the solar thermal energy is beginning from the last decade of April, when the intensity of radiation is 120 kWh m -2 , until the first decade of September. Within this period (approximately 1800 hours), it is possible to use the solar thermal energy by placing solar collectors. The usage of solar collectors for in drying of agricultural production is topical from the viewpoint of decreasing the consumption of energy used for the drying, as electrical energy and fossil energy resources become more expensive and tend to run out. In the processes that concern drying of agricultural production, efficiently enough solar radiation energy can be used. Due to this reason researching continues and expands in the field of usage of solar energy for the processes of drying and heating. The efficiency factor of the existing solar collectors is not high, but they are of simple design and cheep for production and exploitation. By improving the design of the solar collectors and choosing modern materials that absorb the solar radiation energy, it is possible the decrease the efficiency factor of solar collectors and decrease the production costs. In the scientific laboratory of grain drying and storage of Latvia University of Agriculture, a pilot device movable folding solar collector pilot device

  7. Intelligent Transportation and Evacuation Planning A Modeling-Based Approach

    CERN Document Server

    Naser, Arab

    2012-01-01

    Intelligent Transportation and Evacuation Planning: A Modeling-Based Approach provides a new paradigm for evacuation planning strategies and techniques. Recently, evacuation planning and modeling have increasingly attracted interest among researchers as well as government officials. This interest stems from the recent catastrophic hurricanes and weather-related events that occurred in the southeastern United States (Hurricane Katrina and Rita). The evacuation methods that were in place before and during the hurricanes did not work well and resulted in thousands of deaths. This book offers insights into the methods and techniques that allow for implementing mathematical-based, simulation-based, and integrated optimization and simulation-based engineering approaches for evacuation planning. This book also: Comprehensively discusses the application of mathematical models for evacuation and intelligent transportation modeling Covers advanced methodologies in evacuation modeling and planning Discusses principles a...

  8. Evacuation of Bed-bound Patients-STEPS Simulations

    DEFF Research Database (Denmark)

    Madsen, Anne; Dederichs, Anne Simone

    2016-01-01

    Fires in hospitals occur, and evacuation of bed-bound patients might be necessary in case of emergency. The current study concerns the evacuation of bed-bound patients from a fire section in a hospital using hospital porters. The simulations are performed using the STEPS program. The aim...... of the study is to investigate the evacuation time of bed-bound hospital patients using different walking speeds from the literature, and the influence of the number of hospital porters on the total evacuation times of bed-bound patients. Different scenarios were carried out with varying staff......-to-patient ratios that simulate the horizontal evacuation of 40 bed-bound patients into a different fire section. It was found that the staff-to-patient-ratio affects the total evacuation times. However, the total evacuation times do not decrease linearly and a saturation effect is seen at a staff-to-patient ratio...

  9. Evacuation behavior and Three Mile Island.

    Science.gov (United States)

    Cutter, S; Barnes, K

    1982-06-01

    The responses of the residents to the nuclear power plant arcident at Three Mile Island, Pennsylvania illustrate the factors influencing pre-impact coping responses of populations exposed to technological hazards. Confusion itnd ambiguous information influenced both the decision to evaluate and to remain in place. Proximity to the facility, stage in life cycle and the actions of friends and neighbors influenced the decision to evacuate.

  10. Evacuation exercise at the CERN Kindergarten

    CERN Document Server

    2001-01-01

    Every year fire evacuation exercises are organized through out CERN and our facility's Kindergarten is no exception. Just a few weeks ago, a fire simulation was carried out in the Kindergarten kitchen facility using synthetic smoke. The purpose of the exercise was to teach staff to react in a disciplined and professional manner when in the presence of danger. The simulation is always carried out at a random time so as to ensure that people in the area under the test are not aware of the exercise. For the Kindergarten the exercise was held early in the school year so as to train those who are new to the establishment. The evacuation was a complete success and all went as it was supposed to. When the children and teachers smelt smoke they followed the prescribed evacuation routes and left the building immediately. Once outside the situation was revealed as an exercise and everyone went back to business as usual, everyone that is, except the fire brigade and fire inspector. The fire brigade checked that the buil...

  11. Nuclear criticality evacuation with telemonitoring and microprocessors

    International Nuclear Information System (INIS)

    Fergus, R.W.; Moe, H.J. Sr.

    1979-01-01

    At Argonne National Laboratory, criticality alarms are required at widely separated locations to evacuate personnel in case of accident while emergency teams or maintenance personnel respond from a central location. The system functions have been divided in a similar manner. The alarm site hardware can independently detect a criticality and sound the evacuation signal while general monitoring and routine tests are handled by a communication link to a central monitoring station. The radiation detectors and evacuation sounders at each site are interconnected by a common two conductor cable in a unique telemonitoring format. This format allows both control and data information to be received or transmitted at any point on the cable which can be up to 3000 meters total length. The site microprocessor maintains a current data table, detects several faults, drives a printer, and communicates with the central telemonitoring station. The radiation detectors are made with plastic scintillators and photomultiplier tubes operated in a constant current mode with a 4 decade measurement range. The detectors also respond within microseconds to the criticality radiation burst. These characteristics can be tested with an internal light emitting diode either completely with a manual procedure or routinely with a system test initiated by the central monitoring station. Although the system was developed for a criticality alarm which requires reliable and redundant features, the basic techniques are useable for other monitoring and instrumentation applications

  12. Investigating the collector efficiency of silver nanofluids based direct absorption solar collectors

    International Nuclear Information System (INIS)

    Chen, Meijie; He, Yurong; Zhu, Jiaqi; Wen, Dongsheng

    2016-01-01

    Highlights: • An analysis coupled with Radiation transfer, Maxwell and Energy equation is developed. • Plasmonic Au and Ag nanofluids show better photo-thermal conversion properties. • Collector height and particle concentration exist optimum solutions for efficiency. - Abstract: A one-dimensional transient heat transfer analysis was carried out to analyze the effects of the Nanoparticle (NP) volume fraction, collector height, irradiation time, solar flux, and NP material on the collector efficiency. The numerical results were compared with the experimental results obtained by silver nanofluids to validate the model, and good agreement was obtained. The numerical results show that the collector efficiency increases as the collector height and NP volume fraction increase and then reaches a maximum value. An optimum collector height (∼10 mm) and particle concentration (∼0.03%) achieving a collector efficiency of 90% of the maximum efficiency can be obtained under the conditions used in the simulation. However, the collector efficiency decreases as the irradiation time increases owing to the increased heat loss. A high solar flux is desirable to maintain a high efficiency over a wide temperature range, which is beneficial for subsequent energy utilization. The modeling results also show silver and gold nanofluids obtain higher photothermal conversion efficiencies than the titanium dioxide nanofluid because their absorption spectra are similar to the solar radiation spectrum.

  13. Two new designs of parabolic solar collectors

    Directory of Open Access Journals (Sweden)

    Karimi Sadaghiyani Omid

    2014-01-01

    Full Text Available In this work, two new compound parabolic trough and dish solar collectors are presented with their working principles. First, the curves of mirrors are defined and the mathematical formulation as one analytical method is used to trace the sun rays and recognize the focus point. As a result of the ray tracing, the distribution of heat flux around the inner wall can be reached. Next, the heat fluxes are calculated versus several absorption coefficients. These heat flux distributions around absorber tube are functions of angle in polar coordinate system. Considering, the achieved heat flux distribution are used as a thermal boundary condition. After that, Finite Volume Methods (FVM are applied for simulation of absorber tube. The validation of solving method is done by comparing with Dudley's results at Sandia National Research Laboratory. Also, in order to have a good comparison between LS-2 and two new designed collectors, some of their parameters are considered equal with together. These parameters are consist of: the aperture area, the measures of tube geometry, the thermal properties of absorber tube, the working fluid, the solar radiation intensity and the mass flow rate of LS-2 collector are applied for simulation of the new presented collectors. After the validation of the used numerical models, this method is applied to simulation of the new designed models. Finally, the outlet results of new designed collector are compared with LS-2 classic collector. Obviously, the obtained results from the comparison show the improving of the new designed parabolic collectors efficiency. In the best case-study, the improving of efficiency are about 10% and 20% for linear and convoluted models respectively.

  14. Bioinspired plate-based fog collectors.

    Science.gov (United States)

    Heng, Xin; Luo, Cheng

    2014-09-24

    In a recent work, we explored the feeding mechanism of a shorebird to transport liquid drops by repeatedly opening and closing its beak. In this work, we apply the corresponding results to develop a new artificial fog collector. The collector includes two nonparallel plates. It has three advantages in comparison with existing artificial collectors: (i) easy fabrication, (ii) simple design to scale up, and (iii) active transport of condensed water drops. Two collectors have been built. A small one with dimensions of 4.2 × 2.1 × 0.05 cm(3) (length × width × thickness) was first built and tested to examine (i) the time evolution of condensed drop sizes and (ii) the collection processes and efficiencies on the glass, SiO2, and SU-8 plates. Under similar experimental conditions, the amount of water collected per unit area on the small collector is about 9.0, 4.7, and 3.7 times, respectively, as much as the ones reported for beetles, grasses, and metal wires, and the total amount of water collected is around 33, 18, and 15 times. On the basis of the understanding gained from the tests on the small collector, a large collector with dimensions of 26 × 10 × 0.2 cm(3) was further built and tested, which was capable of collecting 15.8 mL of water during a period of 36 min. The amount of water collected, when it is scaled from 36 to 120 min, is about 878, 479, or 405 times more than what was collected by individual beetles, grasses, or metal wires.

  15. Thermal CFD Analysis of Tubular Light Guides

    Directory of Open Access Journals (Sweden)

    Ondřej Šikula

    2013-12-01

    Full Text Available Tubular light guides are applicable for daylighting of windowless areas in buildings. Despite their many positive indoor climate aspects they can also present some problems with heat losses and condensation. A computer CFD model focused on the evaluation of temperature distribution and air flow inside tubular light guides of different dimensions was studied. The physical model of the tested light guides of lengths more than 0.60 m proves shows that Rayleigh numbers are adequate for a turbulent air flow. The turbulent model was applied despite the small heat flux differences between the turbulent and laminar model. The CFD simulations resulted into conclusions that the growing ratio of length/diameter increases the heat transmission loss/linear transmittance as much as by 50 percent. Tubular light guides of smaller diameters have lower heat transmission losses compared to the wider ones of the same lengths with the same outdoor temperature being taken into account. The simulation results confirmed the thermal bridge effect of the tubular light guide tube inside the insulated flat roof details. The thermal transmittance of the studied light guides in the whole roof area was substituted with the point thermal bridges. This substitution gives possibility for simple thermal evaluation of the tubular light pipes in roof constructions.

  16. Experimental study on occupant evacuation in narrow seat aisle

    Science.gov (United States)

    Huang, Shenshi; Lu, Shouxiang; Lo, Siuming; Li, Changhai; Guo, Yafei

    2018-07-01

    Narrow seat aisle is an important area in the train car interior due to the large passenger population, however evacuation therein has not gained enough concerns. In this experimental study, the occupant evacuation of the narrow seat aisle area is investigated, with the aisle width of 0.4-0.6 m and the evacuation direction of forward and backward. The evacuation behaviors are analyzed based on the video record, and the discussion is carried out in the aspect of evacuation time, crowdedness, evacuation order, and aisle conflicts. The result shows that with the increasing aisle width, total evacuation time and the average specific evacuation rate decrease. The aisle is crowded for some time, with a large linear occupant densities. The evacuation order of each occupant is mainly related to the seat position. Moreover, it is found that the aisle conflicts can be well described by Burstedde's model. This study gives a useful benchmark for evacuation simulation of narrow seat aisle, and provides reference to safety design of seat area in train cars.

  17. Dual effects of guide-based guidance on pedestrian evacuation

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Yi, E-mail: yima23-c@my.cityu.edu.hk; Lee, Eric Wai Ming; Shi, Meng

    2017-06-15

    This study investigates the effects of guide-based guidance on the pedestrian evacuation under limited visibility via the simulations based on an extended social force model. The results show that the effects of guides on the pedestrian evacuation under limited visibility are dual, and related to the neighbor density within the visual field. On the one hand, in many cases, the effects of guides are positive, particularly when the neighbor density within the visual field is moderate; in this case, a few guides can already assist the evacuation effectively and efficiently. However, when the neighbor density within the visual field is particularly small or large, the effects of guides may be adverse and make the evacuation time longer. Our results not only provide a new insight into the effects of guides on the pedestrian evacuation under limited visibility, but also give some practical suggestions as to how to assign guides to assist the evacuation under different evacuation conditions. - Highlights: • Extended social force model is used to simulate guided pedestrian evacuation. • Effects of guides on pedestrian evacuation under limited visibility are dual. • Effects of guides on pedestrian evacuation under limited visibility are related to neighbor density within visual field.

  18. Predictive value of impaired evacuation at proctography in diagnosing anismus.

    Science.gov (United States)

    Halligan, S; Malouf, A; Bartram, C I; Marshall, M; Hollings, N; Kamm, M A

    2001-09-01

    We aimed to determine the positive predictive value of impaired evacuation during evacuation proctography for the subsequent diagnosis of anismus. Thirty-one adults with signs of impaired evacuation (defined as the inability to evacuate two thirds of a 120 mL contrast enema within 30 sec) during evacuation proctography underwent subsequent anorectal physiologic testing for anismus. A physiologic diagnosis of anismus was based on a typical clinical history of the condition combined with impaired rectal balloon expulsion or abnormal surface electromyogram. Twenty-eight (90%) of the 31 patients with impaired proctographic evacuation were found to have anismus at subsequent physiologic testing. Among the 28 were all 10 patients who evacuated no contrast medium and all 11 patients with inadequate pelvic floor descent, giving evacuation proctography a positive predictive value of 90% for the diagnosis of anismus. A prominent puborectal impression was seen in only three subjects during proctography, one of whom subsequently showed no physiologic sign of anismus. Impaired evacuation during evacuation proctography is highly predictive for diagnosis of anismus.

  19. Optimization of Evacuation Warnings Prior to a Hurricane Disaster

    Directory of Open Access Journals (Sweden)

    Dian Sun

    2017-11-01

    Full Text Available The key purpose of this paper is to demonstrate that optimization of evacuation warnings by time period and impacted zone is crucial for efficient evacuation of an area impacted by a hurricane. We assume that people behave in a manner consistent with the warnings they receive. By optimizing the issuance of hurricane evacuation warnings, one can control the number of evacuees at different time intervals to avoid congestion in the process of evacuation. The warning optimization model is applied to a case study of Hurricane Sandy using the study region of Brooklyn. We first develop a model for shelter assignment and then use this outcome to model hurricane evacuation warning optimization, which prescribes an evacuation plan that maximizes the number of evacuees. A significant technical contribution is the development of an iterative greedy heuristic procedure for the nonlinear formulation, which is shown to be optimal for the case of a single evacuation zone with a single evacuee type case, while it does not guarantee optimality for multiple zones under unusual circumstances. A significant applied contribution is the demonstration of an interface of the evacuation warning method with a public transportation scheme to facilitate evacuation of a car-less population. This heuristic we employ can be readily adapted to the case where response rate is a function of evacuation number in prior periods and other variable factors. This element is also explored in the context of our experiment.

  20. Heat Pumps With Direct Expansion Solar Collectors

    Science.gov (United States)

    Ito, Sadasuke

    In this paper, the studies of heat pump systems using solar collectors as the evaporators, which have been done so far by reserchers, are reviwed. Usually, a solar collector without any cover is preferable to one with ac over because of the necessity of absorbing heat from the ambient air when the intensity of the solar energy on the collector is not enough. The performance of the collector depends on its area and the intensity of the convective heat transfer on the surface. Fins are fixed on the backside of the collector-surface or on the tube in which the refrigerant flows in order to increase the convective heat transfer. For the purpose of using a heat pump efficiently throughout year, a compressor with variable capacity is applied. The solar assisted heat pump can be used for air conditioning at night during the summer. Only a few groups of people have studied cooling by using solar assisted heat pump systems. In Japan, a kind of system for hot water supply has been produced commercially in a company and a kind of system for air conditioning has been installed in buildings commercially by another company.

  1. Efficiency of the Fermilab Electron Cooler's Collector

    CERN Document Server

    Prost, L R

    2005-01-01

    The newly installed high-energy Recycler Electron Cooling system (REC) at Fermilab will work at an electron energy of 4.34 MeV and a DC beam current of 0.5 A in an energy recovery scheme. For reliable operation of the system, the relative beam current loss must be maintained to levels < 3.e-5. Experiments have shown that the loss is determined by the performance of the electron beam collector, which must retain secondary electrons generated by the primary beam hitting its walls. As a part of the Electron cooling project, the efficiency of the collector for the REC was optimized, both with dedicated test bench experiments and on two versions of the cooler prototype. We find that to achieve the required relative current loss, an axially-symmetric collector must be immersed in a transverse magnetic field with certain strength and gradient prescriptions. Collector efficiencies in various magnetic field configurations, including without a transverse field on the collector, are presented and discussed

  2. Techno-economıc Analysıs of Evacuated Tube Solar Water Heater usıng F-chart Method

    Science.gov (United States)

    Fayaz, H.; Rahim, N. A.; Saidur, R.; Hasanuzzaman, M.

    2018-05-01

    Solar thermal utilization, especially the application of solar water heater technology, has developed rapidly in recent decades. Solar water heating systems based on thermal collector alone or connected with photovoltaic called as photovoltaic-thermal (PVT) are practical applications to replace the use of electrical water heaters but weather dependent performance of these systems is not linear. Therefore on the basis of short term or average weather conditions, accurate analysis of performance is quite difficult. The objective of this paper is to show thermal and economic analysis of evacuated tube collector solar water heaters. Analysis done by F-Chart shows that evacuated tube solar water heater achieves fraction value of 1 to fulfil hot water demand of 150liters and above per day for a family without any auxiliary energy usage. Evacuated tube solar water heater show life cycle savings of RM 5200. At water set temperature of 100°C, RM 12000 is achieved and highest life cycle savings of RM 6100 at the environmental temperature of 18°C are achieved. Best thermal and economic performance is obtained which results in reduction of household greenhouse gas emissions, reduction of energy consumption and saves money on energy bills.

  3. Thermal analysis of a solar collector consisting of V cavities for water heating; Analise termica de um coletor solar composto de cavidades V para aquecimento de agua

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Michel Fabio de Souza

    2009-03-15

    The solar water heating is carried through, in Brazil, by means of solar heaters compound for collectors flat plate of the type plate-and-pipes, devices that operate in stationary position and they do not require tracking of the sun. A compound collector for some formed V-trough concentrators can be an alternative to the conventional solar collectors flat plate. This compound collector for V-trough is considered, each one, for side-walls which are specularly reflecting surfaces associates in V (equivalent to a triangular gutter). Next to the vertex to each V-trough concentrators an absorber tube is fixed, for flow of the fluid to be heated. Interconnection of the absorbers tubes forms a similar tubular network existing in solar collectors of the type the plate and pipe. V-trough concentrators with the absorbers tubes are made use in series in the interior a prismatic box, which have one of its faces consisting by a glass covering and directed toward incidence of the solar radiation. An analysis of thermal performance of these devices operating stationary and without tracking of the sun is researched. A mathematical model for the computational simulation of the optical and thermal performance of these concentrative devices is elaborated, whose implementation was carried through software EES (Engineering Equation Solver). The efficiency optics of V-trough concentrators with cylindrical absorbers is calculated from the adaptation of the methodology used for Fraidenraich (1994), proposal for Hollands (1971) for V-trough cavities with plain absorbers. The thermal analysis of the considered collector was based on the applied methodology the CPC for Hsieh (1981) and Leao (1989). Relative results to the thermal performance of V-trough concentrators suggest that these configurations are not competitive, technique and economically, with the conventional plain collectors. Although some geometric configurations presented next thermal efficiencies to the conventional plain

  4. Transition piece for joining together tubular pieces

    International Nuclear Information System (INIS)

    Holko, K.H.

    1981-01-01

    A transition piece for joining together tubular pieces formed respectively from a low alloy or carbon steel and a high temperature alloy containing at least 16% chromium includes a plurality of tubular parts welded together and formed from materials of selected composition with a maximum chromium content difference of 5% between adjacent parts when the chromium content of each part is below 10% and a maximum chromium difference of 7% between adjacent parts when the chromium content of either part is above 10%. The transition parts are also graded as to such characteristics as thermal expansion coefficient. The transition parts at opposite ends of the transition joint have chromium percentages similar to the tubular pieces to which they are to be joined. The parts may be joined by fusion and/or friction welding and parts may be formed by fusion weld deposition. (author)

  5. Efficiencies of flat plate solar collectors at different flow rates

    DEFF Research Database (Denmark)

    Chen, Ziqian; Furbo, Simon; Perers, Bengt

    2012-01-01

    Two flat plate solar collectors for solar heating plants from Arcon Solvarme A/S are tested in a laboratory test facility for solar collectors at Technical University of Denmark (DTU). The collectors are designed in the same way. However, one collector is equipped with an ETFE foil between...... the absorber and the cover glass and the other is without ETFE foil. The efficiencies for the collectors are tested at different flow rates. On the basis of the measured efficiencies, the efficiencies for the collectors as functions of flow rate are obtained. The calculated efficiencies are in good agreement...

  6. Optimum solar collector fluid flow rates

    DEFF Research Database (Denmark)

    Furbo, Simon; Shah, Louise Jivan

    1996-01-01

    Experiments showed that by means of a standard electronically controlled pump, type UPE 2000 from Grundfos it is possible to control the flow rate in a solar collector loop in such a way that the flow rate is strongly influenced by the temperature of the solar collector fluid passing the pump....... The flow rate is increasing for increasing temperature.The flow rate at the high temperature level is typically 70 % greater than the flow rate at the low temperature level.Further, the energy consumption for the electronically controlled pump in a solar heating system will be somewhat smaller than...... the energy consumption of a normal ciculation pump in the solar heating system.Calculations showed that the highest thermal performances for small SDHW systems based on mantle tanks with constant volume flow rates in the solar collector loops are achieved if the flow rate is situated in the interval from 0...

  7. Recent progress in terrestrial photovoltaic collector technology

    Science.gov (United States)

    Ferber, R. R.

    1982-01-01

    The U.S. Photovoltaic Research and Development Program has the objective to develop the technology necessary to foster widespread grid-competitive electric power generation by the late 1980s. The flat-plate and the concentrator collector activities form the nucleus of the program. The project is concerned with the refining of silicon, silicon sheet production, solar cell processing and fabrication, encapsulation materials development, and collector design and production. The Large-Area Silicon Sheet Task has the objective to develop and demonstrate the feasibility of several methods for producing large area silicon sheet material suitable for fabricating low-cost, high-efficiency solar cells. It is expected that a variety of economic flat-plate and concentrator collectors will become commercially available for grid-connected applications.

  8. Tubular membrane bioreactors for biotechnological processes.

    Science.gov (United States)

    Wolff, Christoph; Beutel, Sascha; Scheper, Thomas

    2013-02-01

    This article is an overview of bioreactors using tubular membranes such as hollow fibers or ceramic capillaries for cultivation processes. This diverse group of bioreactor is described here in regard to the membrane materials used, operational modes, and configurations. The typical advantages of this kind of system such as environments with low shear stress together with high cell densities and also disadvantages like poor oxygen supply are summed up. As the usage of tubular membrane bioreactors is not restricted to a certain organism, a brief overview of various applications covering nearly all types of cells from prokaryotic to eukaryotic cells is also given here.

  9. Assessment of total evacuation systems for tall buildings

    CERN Document Server

    Ronchi, Enrico

    2014-01-01

    This SpringerBrief focuses on the use of egress models to assess the optimal strategy for total evacuation in high-rise buildings. It investigates occupant relocation and evacuation strategies involving the exit stairs, elevators, sky bridges and combinations thereof. Chapters review existing information on this topic and describe case study simulations of a multi-component exit strategy. This review provides the architectural design, regulatory and research communities with a thorough understanding of the current and emerging evacuation procedures and possible future options. A model case study simulates seven possible strategies for the total evacuation of two identical twin towers linked with two sky-bridges at different heights. The authors present the layout of the building and the available egress components including both vertical and horizontal egress components, namely stairs, occupant evacuation elevators (OEEs), service elevators, transfer floors and sky-bridges. The evacuation strategies employ a ...

  10. Qualification test and analysis report: solar collectors

    Energy Technology Data Exchange (ETDEWEB)

    1978-12-01

    Test results show that the Owens-Illinois Sunpak/sup TM/ Model SEC 601 air-cooled collector meets the national standards and codes as defined in the Subsystem Performance Specification and Verification Plan of NASA/MSFC Contract NAS8-32259, dated October 28, 1976. The architectural and engineering firm of Smith, Hinchman and Grylls, Detroit, Michigan, acted in the capacity of the independent certification agency. The program calls for the development, fabrication, qualification and delivery of an air-liquid solar collector for solar heating, combined heating and cooling, and/or hot water systems.

  11. Short-Term Solar Collector Power Forecasting

    DEFF Research Database (Denmark)

    Bacher, Peder; Madsen, Henrik; Perers, Bengt

    2011-01-01

    This paper describes a new approach to online forecasting of power output from solar thermal collectors. The method is suited for online forecasting in many applications and in this paper it is applied to predict hourly values of power from a standard single glazed large area flat plate collector...... enabling tracking of changes in the system and in the surrounding conditions, such as decreasing performance due to wear and dirt, and seasonal changes such as leaves on trees. This furthermore facilitates remote monitoring and check of the system....

  12. Evacuation and assembly of aerogel glazings

    DEFF Research Database (Denmark)

    Jensen, Karsten Ingerslev

    1999-01-01

    The application of monolithic silica aerogel as transparent insulation material for windows has been investigated for some years. It has been realised that a major problem of an industrial production of aerogel glazings will be the time for evacuation of the aerogel material. However, in a previous...... process, it can be considered as semi-online, and especially the capital cost is significantly lower for this method in comparison with a true online process. So hereby, a major obstacle is overcome with respect to a first industrial production of aerogel glazings.The apparatus has been constructed...

  13. Bulkhead Door – Critical Evacuation States

    Directory of Open Access Journals (Sweden)

    Flizikowski Józef

    2017-03-01

    Full Text Available The article is a preliminary to a modification concept of the sliding watertight bulkhead door used on ships and vessels. Hydraulic or electro-hydraulic drives used to move these doors require complicated and extended pressure installations with large amounts of hydraulic fluid. Well-known operational drawbacks of these installations include high level of noise and possibility of various leaks in the hydraulic system. Being the first in a series, the present article describes and analyses critical states which can take place during evacuation of people through openings in the watertight bulkhead doors on seagoing ships and vessels.

  14. APPROXIMATION OF THE TIME TO INITIATE THE EVACUATION

    Directory of Open Access Journals (Sweden)

    Jiří POKORNÝ

    2016-06-01

    Full Text Available One of the basic prerequisites for securing the safety of people at large group events is to ensure their evacuation in case of emergencies. This article deals with the approximations of time to initiate the evacuation of persons in case of a fire at large group events organized in outdoor spaces. The solution is based on the principles of determining the period to initiate the evacuation of persons in terms of international ISO standards. Considering the specificities of the given outdoor space and possible related security measures, the article recommends the relevant sufficient amount of time to initiate an evacuation.

  15. Evacuation routes performances and fire safety of buildings

    Directory of Open Access Journals (Sweden)

    Laban Mirjana Đ.

    2015-01-01

    Full Text Available Residential buildings, public and business facilities with large number of occupants are particularly exposed to the risk of event with catastrophic consequences, especially in case of fire. Evacuation routes must be separated fire compartments with surfaces made of non-combustible materials. Safe evacuation of building occupants in case of fire is a crucial requirement for the preservation of human life in building. In our engineering practice, calculation model is usually applied in order to determine the time required for evacuation (SRPS TP 21. However, evacuation simulation models are more present in research papers, contributing to better assessment of flow of evacuation in the real time. These models could provide an efficient way of testing the safety of a building in the face of fire and indicate critical points at the evacuation paths. Computer models enable the development and analysis of multiple various scenarios during a fire event, contributing to defining the measures for improving the safety of the building in case of fire. This paper analyses the fulfilment of technical requirements for the safe evacuation and proposes improvement measures based on a comparative analysis of the time required for occupants' evacuation from the building (Department of Civil Engineering and Geodesy in Novi Sad, obtained by calculation model and by using evacuation simulation software.

  16. Study on rapid evacuation in high-rise buildings

    Directory of Open Access Journals (Sweden)

    Xin Zhang

    2017-06-01

    Full Text Available More and more high rising buildings emerged in modern cities, but emergency evacuation of tall buildings has been a worldwide difficult problem. In this paper, a new evacuation device for high rising buildings in fire accident was proposed and studied. This device mainly consisted of special spiral slideway and shunt valve. People in this device could fast slide down to the first floor under gravity without any electric power and physical strength, which is suitable for various emergency evacuation including mobility-impaired persons. The plane simulation test has shown that human being in alternative clockwise and counterclockwise movement will not become dizzy. The evacuated people should wear protection pad, which can prevent slider from being injured by surface friction with the slide, and eliminate the friction coefficient difference caused by different clothes and slide surface. The calculation results show that the evacuation speed of the new device is much faster than traditional staircases. Moreover, such new evacuation device can also be used as a means of vertical transportation in high-rise buildings partly. People can take it from any floor to ground floor directly, which not only save time for waiting for the lifts but also save the power. The new evacuation system is of simple structure, easy to use, and suitable for evacuation and partly used as vertical downwards traffic, which shows light on solving world-wide difficulties on fast evacuation in high-rise buildings.

  17. Ranitidine has no influence on tubular creatinine secretion

    NARCIS (Netherlands)

    van den Berg, J. G.; Koopman, M. G.; Arisz, L.

    1996-01-01

    Oral cimetidine competitively inhibits tubular secretion of creatinine. We investigated the potential of oral ranitidine, a comparable H2-receptor antagonist, to block tubular creatinine secretion. In 10 healthy subjects, clearances of inulin and endogenous creatinine were simultaneously measured

  18. The effect and contribution of wind generated rotation on outlet temperature and heat gain of LS-2 parabolic trough solar collector

    Directory of Open Access Journals (Sweden)

    Sadaghiyani Omid Karimi

    2013-01-01

    Full Text Available The Monte Carlo ray tracing method is applied and coupled with finite volume numerical methods to study effect of rotation on outlet temperature and heat gain of LS-2 parabolic trough concentrator (PTC. Based on effect of sunshape, curve of mirror and use of MCRT, heat flux distribution around of inner wall of evacuated tube is calculated. After calculation of heat flux, the geometry of LS-2 Luz collector is created and finite volume method is applied to simulate. The obtained results are compared with Dudley et al test results for irrotational cases to validate these numerical solving models. Consider that, for rotational models ,the solving method separately with K.S. Ball's results. In this work, according to the structure of mentioned collector, we use plug as a flow restriction. In the rotational case studies, the inner wall rotates with different angular speeds. We compare results of rotational collector with irrotational. Also for these two main states, the location of plug changed then outlet temperature and heat gain of collector are studied. The results show that rotation have positive role on heat transfer processing and the rotational plug in bottom half of tube have better effectual than upper half of tube. Also the contribution of rotation is calculated in the all of case studies. Working fluid of these study is one of the oil derivatives namely Syltherm-800. The power of wind can be used to rotate tube of collector.

  19. Drill pipes and casings utilizing multi-conduit tubulars

    Energy Technology Data Exchange (ETDEWEB)

    Curlett, H.B.

    1989-01-24

    A seal adapted for use with a multi-conduit well tubular, or the like, is described which consists of: a plate with fluid passages, each passage corresponding to an opening of a conduit of the multiconduit tubular, and a groove on the plate around each passage; and elastomer means partially embeddable into each groove for sealing each conduit of a tubular to a corresponding conduit of another similar tubular.

  20. Development of Partial Tubular Flat Knitting Fabric Composite Preform

    Directory of Open Access Journals (Sweden)

    Jiang Wei Qing

    2016-01-01

    Full Text Available After building some structures of partial tubular flat knitting fabric composite preform, the influencing factor on tubular section was analyzed and the fabric was knitted selectively. The partial tubular flat knitting fabric composite preform were Knitted by changing different yarn, row number and two-sided partial tubular flat knitting fabric. Multilayer sheet would be got after hot pressing and it has big market prospects and good application value.

  1. Comparison of three different collectors for process heat applications

    Science.gov (United States)

    Brunold, Stefan; Frey, R.; Frei, Ulrich

    1994-09-01

    In general vacuum tube collectors are used in solar process heat systems. Another possibility is to use transparent insulated flat plate collectors. A critical point however, is that most of the common transparent insulating materials can not withstand high temperatures because they consist of plastics. Thus, temperature resistive collector covers combining a high tranmisivity with a low U-value are required. One possibility is to use capillaries made of glass instead of plastics. Measurement results of collector efficiency and incident angle modifier will be presented as well as calculated energy gains for three different collectors: a vacuum tube collector (Giordano Ind., France), a CPC vacuum tube collector (microtherm Energietechnik Germany; a new flat plate collector using glass capillary as transparent insulation (SET, Germany).

  2. Behavior of a solar collector loop during stagnation

    DEFF Research Database (Denmark)

    Chen, Ziqian; Dragsted, Janne; Furbo, Simon

    2015-01-01

    A mathematical model simulating the emptying behavior of a pressurized solar collector loop with solar collectors with a good emptying behavior is developed and validated with measured data. The calculated results are in good agreement with the measured results. The developed simulation model...... is therefore suitable to determine the behavior of a solar collector loop during stagnation. A volume ratio R, which is the ratio of the volume of the vapour in the upper pipes of the solar collector loop during stagnation and the fluid content of solar collectors, is introduced to determine the mass...... of the collector fluid pushed into the expansion vessel during stagnation, Min. A correlation function for the mass Min and the volume ratio R for solar collector loops is obtained. The function can be used to determine a suitable size of expansion vessels for solar collector loops....

  3. Two-axis movable concentrating solar energy collector

    Science.gov (United States)

    Perkins, G. S.

    1977-01-01

    Proposed solar-tracker collector assembly with boiler in fixed position, allows use of hard line connections, capable of withstanding optimum high temperature fluid flow. System thereby eliminates need for flexible or slip connection previously used with solar collector systems.

  4. Tubular permanent magnet actuators: cogging forces characterization

    NARCIS (Netherlands)

    Paulides, J.J.H.; Janssen, J.L.G.; Encica, L.; Lomonova, E.A.

    2009-01-01

    Tubular permanent magnet actuators are evermore used in demanding industrial and automotive applications. However, these actuators can suffer from large cogging forces, which have a destabilizing effect on the servo control system and compromise position and speed control accuracy. This paper

  5. Work tool in a tubular element

    International Nuclear Information System (INIS)

    Griffaton, J.

    1991-01-01

    The stand, which is positioned in relation with the tubular element, has clutch disengagement means for a working rod in rotation, with at least two positioning regions on the rod. Application for laser welding a sleeve into PWR steam generator tubes [fr

  6. Boron--epoxy tubular structure members

    Science.gov (United States)

    Shakespeare, W. B. J.; Nelson, P. T.; Lindkvist, E. C.

    1973-01-01

    Composite materials fabricate thin-walled tubular members which have same load-carrying capabilities as aluminum, titanium, or other metals, but are lighter. Interface between stepped end fitting and tube lends itself to attachments by primary as well as secondary bonding. Interlaminar shear and hoop stress buildup in attachment at end fitting is avoided.

  7. Pointlike Inclusion Interactions in Tubular Membranes

    NARCIS (Netherlands)

    Vahid Belarghou, A.; Idema, T.

    2016-01-01

    Membrane tubes and tubular networks are ubiquitous in living cells. Inclusions like proteins are vital for both the stability and the dynamics of such networks. These inclusions interact via the curvature deformations they impose on the membrane. We analytically study the resulting membrane

  8. A Simulation Tool for Hurricane Evacuation Planning

    Directory of Open Access Journals (Sweden)

    Daniel J. Fonseca

    2009-01-01

    Full Text Available Atlantic hurricanes and severe tropical storms are a serious threat for the communities in the Gulf of Mexico region. Such storms are violent and destructive. In response to these dangers, coastal evacuation may be ordered. This paper describes the development of a simulation model to analyze the movement of vehicles through I-65, a major US Interstate highway that runs north off the coastal City of Mobile, Alabama, towards the State of Tennessee, during a massive evacuation originated by a disastrous event such a hurricane. The constructed simulation platform consists of a primary and two secondary models. The primary model is based on the entry of vehicles from the 20 on-ramps to I-65. The two secondary models assist the primary model with related traffic events such as car breakdowns and accidents, traffic control measures, interarrival signaling, and unforeseen emergency incidents, among others. Statistical testing was performed on the data generated by the simulation model to indentify variation in relevant traffic variables affecting the timely flow of vehicles travelling north. The performed statistical analysis focused on the closing of alternative on-ramps throughout the Interstate.

  9. Pedestrian Dynamics Feedback Control of Crowd Evacuation

    CERN Document Server

    Kachroo, Pushkin P.E; Al-nasur, Sadeq J; Shende, Apoorva

    2008-01-01

    Effective evacuation of people from closed spaces is an extremely important topic, since it can save real lives in emergency situations that can be brought about by natural and human made disasters. Usually there are static maps posted at various places at buildings that illustrate routes that should be taken during emergencies. However, when disasters happen, some of these routes might not be valid because of structural problems due to the disaster itself and more importantly because of the distribution of congestion of people spread over the area. The average flow of traffic depends on the traffic density. Therefore, if all the people follow the same route, or follow a route without knowing the congestion situation, they can end up being part of the congestion which results in very low flow rate or worse a traffic jam. Hence it becomes extremely important to design evacuations that inform people how fast and in which direction to move based on real-time information obtained about the people distribution usi...

  10. Evacuate or Shelter-in-place? The Role of Corporate Memory and Political Environment in Hospital-evacuation Decision Making.

    Science.gov (United States)

    Ricci, Karen A; Griffin, Anne R; Heslin, Kevin C; Kranke, Derrick; Dobalian, Aram

    2015-06-01

    Hospital-evacuation decisions are rarely straightforward in protracted advance-warning events. Previous work provides little insight into the decision-making process around evacuation. This study was conducted to identify factors that most heavily influenced the decisions to evacuate the US Department of Veterans Affairs (VA) New York Harbor Healthcare System's (NYHHS; New York USA) Manhattan Campus before Hurricane Irene in 2011 and before Superstorm Sandy in 2012. Semi-structured interviews with 11 senior leaders were conducted on the processes and factors that influenced the evacuation decisions prior to each event. The most influential factor in the decision to evacuate the Manhattan Campus before Hurricane Irene was New York City's (NYC's) hospital-evacuation mandate. As a federal facility, the Manhattan VA medical center (VAMC) was exempt from the city's order, but decision makers felt compelled to comply. In the case of Superstorm Sandy, corporate memory of a similar 1992 storm that crippled the Manhattan facility drove the decision to evacuate before the storm hit. Results suggest that hospital-evacuation decisions are confounded by political considerations and are influenced by past disaster experience. Greater shared situational awareness among at-risk hospitals, along with a more coordinated approach to evacuation decision making, could reduce pressure on hospitals to make these high-stakes decisions. Systematic mechanisms for collecting, documenting, and sharing lessons learned from past disasters are sorely needed at the institutional, local, and national levels.

  11. Reliability Analysis of Tubular Joints in Offshore Structures

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle; Sørensen, John Dalsgaard

    1987-01-01

    Reliability analysis of single tubular joints and offshore platforms with tubular joints is" presented. The failure modes considered are yielding, punching, buckling and fatigue failure. Element reliability as well as systems reliability approaches are used and illustrated by several examples....... Finally, optimal design of tubular.joints with reliability constraints is discussed and illustrated by an example....

  12. A tool for standardized collector performance calculations including PVT

    DEFF Research Database (Denmark)

    Perers, Bengt; Kovacs, Peter; Olsson, Marcus

    2012-01-01

    A tool for standardized calculation of solar collector performance has been developed in cooperation between SP Technical Research Institute of Sweden, DTU Denmark and SERC Dalarna University. The tool is designed to calculate the annual performance of solar collectors at representative locations...... can be tested and modeled as a thermal collector, when the PV electric part is active with an MPP tracker in operation. The thermal collector parameters from this operation mode are used for the PVT calculations....

  13. PERFORMANCE EVALUATION OF SOLAR COLLECTORS USING A SOLAR SIMULATOR

    OpenAIRE

    M. Norhafana; Ahmad Faris Ismail; Z. A. A. Majid

    2015-01-01

    Solar water heating systems is one of the applications of solar energy. One of the components of a solar water heating system is a solar collector that consists of an absorber. The performance of the solar water heating system depends on the absorber in the solar collector. In countries with unsuitable weather conditions, the indoor testing of solar collectors with the use of a solar simulator is preferred. Thus, this study is conducted to use a multilayered absorber in the solar collector of...

  14. Local Reasoning about a Copying Garbage Collector

    DEFF Research Database (Denmark)

    Torp-Smith, Noah; Birkedal, Lars; Reynolds, John C.

    2008-01-01

    We present a programming language, model, and logic appropriate for implementing and reasoning about a memory management system. We state semantically what is meant by correctness of a copying garbage collector, and employ a variant of the novel separation logics to formally specify partial corre...

  15. 31 CFR 203.17 - Collector depositaries.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false Collector depositaries. 203.17 Section 203.17 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) FISCAL SERVICE, DEPARTMENT OF THE TREASURY FINANCIAL MANAGEMENT SERVICE PAYMENT OF FEDERAL TAXES AND THE TREASURY...

  16. Copyright, Property and the Film Collector

    Science.gov (United States)

    Nevins, Francis M., Jr.

    1975-01-01

    Legal issues surrounding the collecting of movies are analyzed with the conclusion that neither law nor public policy supports a cause for action against the ultimate consumer of film prints and that it is not in a studio's economic interest to bring such actions against collectors. (JT)

  17. Diffraction patterns from 7-Angstroms tubular halloysite

    International Nuclear Information System (INIS)

    Eggleton, T.

    1998-01-01

    Full text: The diffraction patterns from 7-Angstroms tubular halloysite are superficially like those from kaolinite. Diffraction from a tubular aggregate of atoms, however, differs from that from a crystal because there is no linear repetition in two of the three conventional crystallographic directions. In tubular halloysite, the tube axis is [010] or [110] and in this direction the unit cell repeats in the normal linear fashion. The x-axis, by contrast, changes direction tangentially around the tube circumference, and there can be no true z-axis, because unit cells in the radial direction do not superimpose, since each successive tubular layer has a larger radius than its predecessor and therefore must contain more unit cells than its predecessor. Because tubular 'crystals' do not have a lattice repeat, use of Bragg 'hkl' indices is not appropriate. In the xy plane, a small area of the structure approximates a flat layer silicate, and hk indices may been used to label diffraction maxima. Similarly, successive 1:1 layers tangential to the tube walls yield a series of apparent 001 diffraction maxima. Measurement of these shows that the d-spacings do not form an exact integral series. The reason for this lies in the curvature of the structure. Calculated electron and powder X-ray diffraction patterns, based on a model of concentric 1:1 layers with no regular relation between them other than the 7.2 Angstroms spacing, closely simulate the observed data. Evidence for the 2-layer structure that is generally accepted may need to be reassessed in the light of these results

  18. Colored solar collectors - Annual report 2006

    Energy Technology Data Exchange (ETDEWEB)

    Schueler, A.; Chambrier, E. De; Roecker, Ch.; Scartezzini, J.-L.

    2007-12-15

    The architectural integration of thermal solar collectors into buildings is often limited by their black color, and the visibility of tubes and corrugations of the absorber sheets. A certain freedom in color choice would be desirable, but the colored appearance should not cause an excessive degradation of the collector efficiency. Multilayered thin film interference filters on the collector glazing can produce a colored reflection, hiding the corrugated metal sheet, while transmitting the non-reflected radiation entirely to the absorber. These interference filters are designed and optimized by numerical simulation, and are manufactured by sol-gel dip-coating or magnetron sputtering. The novel colored glazed solar collectors will be ideally suited for architectural integration into buildings, e.g. as solar active glass facades. Due to the tunability of the refractive index, nanostructured materials such as SiO{sub 2}:TiO{sub 2} composites and porous SiO{sub 2} are very useful for application in multilayer interference stacks. Novel quaternary Mg-F-Si-O films exhibit a surprisingly low refractive index and are therefore promising candidates for highly transparent coatings on solar collector glazing. The nanostructure of these thin films is studied by transmission electron microscopy, while the optical constants are measured precisely by ellipsometry. For a convincing demonstration, sufficiently large samples of high quality are imperatively needed. The fabrication of nanocomposite SiO{sub 2}:TiO{sub 2} films has been demonstrated by sol-gel dip-coating of A4-sized glass panes. The produced coatings exhibit a colored reflection in combination with a high solar transmittance, a homogenous appearance, and are free of visible defects. Film hardening by UV exposure will result in speeding up the sol-gel process and saving energy, thereby reducing costs significantly. The infrastructure for UV-curing has been established. A UV C radiation source can now be attached to the

  19. 78 FR 37584 - U.S. Steel Tubular Products, Inc., Mckeesport Tubular Operations Division, Subsidiary of United...

    Science.gov (United States)

    2013-06-21

    ... make the following certification: All workers of U.S. Steel Tubular Products, McKeesport Tubular... Products, Inc., Mckeesport Tubular Operations Division, Subsidiary of United States Steel Corporation, Mckeesport, Pennsylvania; Notice of Amended Certification Pursuant to Section 221 of the Trade Act of 1974...

  20. Intrarectal pressures and balloon expulsion related to evacuation proctography.

    Science.gov (United States)

    Halligan, S; Thomas, J; Bartram, C

    1995-01-01

    Seventy four patients with constipation were examined by standard evacuation proctography and then attempted to expel a small, non-deformable rectal balloon, connected to a pressure transducer to measure intrarectal pressure. Simultaneous imaging related the intrarectal position of the balloon to rectal deformity. Inability to expel the balloon was associated proctographically with prolonged evacuation, incomplete evacuation, reduced anal canal diameter, and acute anorectal angulation during evacuation. The presence and size of rectocoele or intussusception was unrelated to voiding of paste or balloon. An independent linear combination of pelvic floor descent and evacuation time on proctography correctly predicted maximum intrarectal pressure in 74% of cases. No patient with both prolonged evacuation and reduced pelvic floor descent on proctography could void the balloon, as maximum intrarectal pressure was reduced in this group. A prolonged evacuation time on proctography, in combination with reduced pelvic floor descent, suggests defecatory disorder may be caused by inability to raise intrarectal pressure. A diagnosis of anismus should not be made on proctography solely on the basis of incomplete/prolonged evacuation, as this may simply reflect inadequate straining. PMID:7672656

  1. Clarifying evacuation options through fire behavior and traffic modeling

    Science.gov (United States)

    Carol L. Rice; Ronny J. Coleman; Mike. Price

    2011-01-01

    Communities are becoming increasingly concerned with the variety of choices related to wildfire evacuation. We used ArcView with Network Analyst to evaluate the different options for evacuations during wildfire in a case study community. We tested overlaying fire growth patterns with the road network and population characteristics to determine recommendations for...

  2. 14 CFR 121.570 - Airplane evacuation capability.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Airplane evacuation capability. 121.570... REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Flight Operations § 121.570 Airplane evacuation capability. (a) No person may cause an airplane carrying passengers to be moved on the surface, take off, or...

  3. Standardized performance tests of collectors of solar thermal energy - A flat-plate copper collector with parallel mylar striping

    Science.gov (United States)

    Johnson, S. M.

    1976-01-01

    Basic test results are reported for a flat plate solar collector whose performance was determined in a solar simulator. The collector was tested over ranges of inlet temperatures, fluxes and one coolant flow rate. Collector efficiency is correlated in terms of inlet temperature and flux level.

  4. Standardized performance tests of collectors of solar thermal energy: A selectively coated, steel collector with one transparent cover

    Science.gov (United States)

    1976-01-01

    Basic test results are presented of a flat-plate solar collector whose performance was determined in solar simulator. The collector was tested over ranges of inlet temperatures, fluxes and coolant flow rates. Collector efficiency was correlated in terms of inlet temperature and flux level.

  5. Computer simulation-based framework for transportation evacuation in major trip generator.

    Science.gov (United States)

    2009-01-01

    Since emergencies including both natural disasters and man-made incidents, are happening more and more : frequently, evacuation, especially transportation evacuation, is becoming a hot research focus in recent years. : Currently, transportation evacu...

  6. Vakuumrørsolfangere fra Kina

    DEFF Research Database (Denmark)

    Qin, Lin; Furbo, Simon

    1999-01-01

    Recently a number of Chinese companies started mass production of evacuated tubular solar collectors. Contrary to Europe, in China the evacuated tubular solar collectors have reached such a low price level that it has become normal to use these high-efficient solar collectors in many different...... types of solar heating systems.Four different evacuated tubular solar collectors produced by Chinese companies have been tested in a small solar domestic hot water test system. The test system has been tested under realistic conditions in a test facility for solar heating systems at DTU. By means...... of the tests a simulation model has been developed for each of the four solar collectors.With the developed models calculations of the yearly thermal performance of different Danish solar heating systems were carried out: Small and large solar domestic hot water systems, combined solar domestic hot water...

  7. Evacuation proctography - examination technique and method of evaluation

    International Nuclear Information System (INIS)

    Braunschweig, R.; Schott, U.; Starlinger, M.

    1993-01-01

    Evacuation proctography is the most important imaging technique to supplement findings of physical examination, manometry, and endoscopy in patients presenting with pathologies in anorectal morphology and function. Indications for evacuation proctography include obstructed defecation or incomplete evacuation, imaging of ileal pouches following excision of the rectum, and suspected anorectal fistulae. Evacuation proctography with thick barium sulfate is performed under fluoroscopy. Documentation of the study can either be done by single-shot X-rays, video recording, or imaging with a 100-mm spot-film camera. Evacuation proctography shows morphologic changes such as spastic pelvic floor, rectocele, enterocele, intussusception and anal prolapse. Measurements can be performed to obtain the anorectal angle, location and mobility of the pelvic floor, and size as well as importance of a rectocele. Qualitative and quantitative data can only be interpreted along with clinical and manometric data. (orig.) [de

  8. Arrangement, manufacturing process and use of solar heat collectors

    Energy Technology Data Exchange (ETDEWEB)

    Scheel, H W

    1978-03-30

    Solar collectors generally have a timber or metal frame where the transparent front cover, usually of glass, is replaceable. In order to prevent great deformation, such a frame must be relatively stable and of heavy construction, which may lead to difficulties in mounting the collector on the roofs or front walls of houses. The present invention proposes a light but nevertheless rigid collector frame, which consists of plastic material and is constructed so that the installation and replacement of collectors can be realized. Further, collectors are proposed which guarantee a minimum of reflection and are so designed that an optimum architectural effect is produced.

  9. Solar collector design with respect to moisture problems

    DEFF Research Database (Denmark)

    Holck, Ole; Svendsen, Svend; Brunold, Stefan

    2003-01-01

    more ventilation openings should be made and what influence the insulation material has. Guidelines for collector designers are proposed. The design guidelines provide some suggestions to be considered during the design of solar collectors.The work was carried out within the framework of the working...... group Materials in Solar Thermal Collectors of the International Energy Agency-Solar Heating and Cooling Programme....... the design of the collector, the location and size of ventilation holes, properties of the insulation materials and dimension of the solar collector box are parameters that have to be taken into account for the optimisation in order to achieve the most favourable microclimate to prevent corrosion...

  10. Research on evacuation planning as nuclear emergency preparedness

    International Nuclear Information System (INIS)

    Yamamoto, Kazuya

    2007-10-01

    The International Atomic Energy Agency (IAEA) has introduced new concepts of precautionary action zone (PAZ) and urgent protective action planning zone (UPZ) in 'Preparedness and Response for a Nuclear or Radiological Emergency' (GS-R-2 (2002)), in order to reduce substantially the risk of severe deterministic health effects. Open literature based research was made to reveal problems on evacuation planning and the preparedness for nuclear emergency arising from introduction of PAZ into Japan that has applied the emergency planning zone (EPZ) concept currently. In regard to application of PAZ, it should be noted that the requirements for preparedness and response for a nuclear or radiological emergency are not only dimensional but also timely. The principal issue is implementation of evacuation of precautionary decided area within several hours. The logic of evacuation planning for a nuclear emergency and the methods of advance public education and information in the U.S. is effective for even prompt evacuation to the outside of the EPZ. As concerns evacuation planning for a nuclear emergency in Japan, several important issues to be considered were found, that is, selection of public reception centers which are outside area of the EPZ, an unique reception center assigned to each emergency response planning area, public education and information of practical details about the evacuation plan in advance, and necessity of the evacuation time estimates. To establish a practical evacuation planning guide for nuclear emergencies, further researches on application of traffic simulation technology to evacuation time estimates and on knowledge of actual evacuation experience in natural disasters and chemical plant accidents are required. (author)

  11. Integrated Design of Undepressed Collector for Low Power Gyrotron

    Science.gov (United States)

    Kumar, Anil; Goswami, Uttam K.; Poonia, Sunita; Singh, Udaybir; Kumar, Nitin; Alaria, M. K.; Bera, A.; Khatun, Hasina; Sinha, A. K.

    2011-06-01

    A 42 GHz, 200 kW continuous wave (CW) gyrotron, operating at TE03 mode is under development for the electron cyclotron resonance plasma heating of the Indian TOKAMAK system. The gyrotron is made up of an undepressed collector. The undepressed collector is simple to design and cost effective. In this paper, a detailed design study of the undepressed collector for the 42 GHz gyrotron is presented. The EGUN code is used to analyze the spent electron beam trajectory for the maximum spread to reduce the power loading on the collector surface. To achieve wall loading ≤1 kW/cm2, a collector with a length of 800 mm and a radius of 42.5 mm is designed. The design also includes the three magnet systems around the collector for maximum and uniform beam spread. The thermal and the structural analyses are done using the ANSYS code to optimize the collector structure and dimensions with tolerance.

  12. SOFC mini-tubulares basadas en YSZ

    Directory of Open Access Journals (Sweden)

    Campana, R.

    2008-08-01

    Full Text Available Tubular SOFC have the advantage over planar SOFC of the low temperature sealing and more resistance to thermal shock. On the other hand the volumetric power density of tubular Fuel Cells goes with the inverse of the tube diameter which added to the faster warm-up kinetics makes low diameter tubular SOFC favorable for low power applications. Anode supported tubular SOFC of 3mm diameter and 150 mm length with YSZ electrolyte were fabricated and tested by V-I measurements using H2-Ar (5, 10, 100 vol% as fuel and air for the cathode. The NiO-YSZ tubes of about 400 μm thickness were produced by hydrostatic pressure and then coated with an YSZ film of 15-20 μm. The electrolyte was deposited using a manual aerograph. After sintering either Pt paste or LSF (with YSZ or SDC coatings of about 20-50 μm thickness were deposited for the cathode. The OCV of the cells were excellent, very close to the expected Nernst law prediction indicating that there were not gas leaks. The maximun electrical power of the cell was near to 500mW/cm2 at 850ºC operation temperature. Complex impedance measurements of the cells were performed in order to determine the resistance of the different cell components.

    La principal ventaja de las SOFC tubulares frente a las planares es el sellado de la cámara anódica y catódica a bajas temperaturas. Además la densidad de energía volumétrica de las pilas tubulares es inversamente proporcional al diámetro del tubo, que añadido a los tiempos cortos de encendido y apagado hacen que las mini-tubulares sean interesantes para usos de baja potencia. Se han fabricado y caracterizado SOFC tubulares soportadas en ánodo de 3mm de diámetro y de 150 mm de longitud, 400μm de espesor, con electrolito de YSZ depositado por spray de 15-20 μm. Los tubos de NiO-YSZ son producidos por prensado isostático. La caracterización eléctrica se ha realizado empleando H2-Ar como combustible an

  13. A total cost perspective on use of polymeric materials in solar collectors – Importance of environmental performance on suitability

    International Nuclear Information System (INIS)

    Carlsson, Bo; Persson, Helena; Meir, Michaela; Rekstad, John

    2014-01-01

    Highlights: • A polymeric solar collector system was compared with two traditional ones. • It was found the best in terms of climatic performance per solar heat collected. • The differences in climatic cost between the systems compared however are small. • The low climatic cost makes solar heating better compared to natural gas heating. • Use of Ecoindicator 99 for environmental cost makes solar heating even better. - Abstract: To assess the suitability of solar collector systems in which polymeric materials are used versus those in which more traditional materials are used, a case study was undertaken. In this case study a solar heating system with polymeric solar collectors was compared with two equivalent but more traditional solar heating systems: one with flat plate solar collectors and one with evacuated tube solar collectors. To make the comparison, a total cost accounting approach was adopted. The life cycle assessment (LCA) results clearly indicated that the polymeric solar collector system is the best as regards climatic and environmental performance when they are expressed in terms of the IPPC 100 a indicator and the Ecoindicator 99, H/A indicator, respectively. In terms of climatic and environmental costs per amount of solar heat collected, the differences between the three kinds of collector systems were small when compared with existing energy prices. With the present tax rates, it seems unlikely that the differences in environmental and climatic costs will have any significant influence on which system is the most favoured, from a total cost point of view. In the choice between a renewable heat source and a heat source based on the use of a fossil fuel, the conclusion was that for climatic performance to be an important economic factor, the tax or trade rate of carbon dioxide emissions must be increased significantly, given the initial EU carbon dioxide emission trade rate. The rate would need to be at least of the same order of magnitude

  14. Preheating of tap water with solar collectors

    Energy Technology Data Exchange (ETDEWEB)

    Granum, H; Raaen, H

    1992-05-05

    In 1991 SINTEF Architecture and Building Technology won the second prize in 'The Nordic Competition for Low Energy Buildings' with a project proposal named 'LOWe'. The paper gives a description of the energy-saving features of this project, particularly the use of a solar collector for preheating of tap water. Compared with the economic profitability of other saving efforts in the project, such as good thermal insulation and efficient heat recovering system, the system for solar preheating of tap water does not seem very attractive for the time being. Loose estimates indicate a cost of close of NOK 1.00 per kWh for the produced energy in the solar collector, while the present price for electricity in Norway is about NOK 0.50 per kWh. Compared with a heat pump solution however the energy cost is not unreasonable.

  15. Assessment of musculoskeletal load in refuse collectors

    Directory of Open Access Journals (Sweden)

    Zbigniew W. Jóźwiak

    2013-08-01

    Full Text Available Background: The aim of this work was to assess the load on the musculoskeletal system and its effects in the collectors of solid refuse. The rationale behind this study was to formulate proposals how to reduce excessive musculoskeletal load in this group of workers. Material and Methods: The study group comprised 15 refuse collectors aged 25 to 50 years. Data about the workplace characteristics and subjective complaints of workers were collected by the free interview and questionnaire. During the survey the photorecording of the workpostures, the distance and velocity by GPS recorders, measurements of forces necessary to move containers, energy expenditure (lung ventilation method, workload estimation using the Firstbeat system and REBA method and stadiometry were done. Results: The distance walked daily by the collectors operating in terms of 2 to 3 in urban areas was about 15 km, and in rural areas about 18 km. The most frequent musculoskeletal complaints concerned the feet (60% subjects, knees, wrists and shoulders (over 40% subjects. After work-shift all examined workers had vertebral column shorter by 10 to 14 mm (11.4 mm mean. Conclusions: The results of our study show that the refuse collectors are subjected to a very high physical load because of the work organization and the way it is performed. To avoid adverse health effects and overload it is necessary to undertake ergonomic interventions, involving training of workers to improve the way of their job performance, active and passive leisure, technical control of the equipment and refuse containers, as well as the renegotiation of contracts with clients, especially those concerning non-standard containers. Med Pr 2013;64(4:507–519

  16. Theoretical study of fluidized solar collector performance

    Energy Technology Data Exchange (ETDEWEB)

    Adulla, S. H; Kassem, M A; El-Refaie, M. F. [Cairo University, Giza (Egypt)

    2000-07-01

    This work presents a proposed novel design aiming to increasing the absorber-to-fluid heat transfer coefficient. This is accomplished by introducing small solid particles inside the collector tubes. When the collector liquid flows, it causes the particles to be fluidized and spread in the tubes. The particles material, size and total number should be turned together with the fluid mass flow rate to keep the bed, or particle dispersion, length within the physical length of collector tubes. Thus, the particles would be confined in the collector only; and not carried over to other parts of the circulation loop. While moving, the particles erode the thermal boundary layer formed on the tube inner surface, hence increasing the heat transfer coefficient. [Spanish] Este articulo presenta un diseno novedoso destinado a aumentar el coeficiente de trasferencia de calor de absorbedor a fluido. Esto se lleva a cabo mediante la introduccion de particulas solidas dentro de los tubos del colector. Cuando fluye el liquido del colector origina que las particulas se fluidicen y se diseminen en los tubos. El material de las particulas, tamano y numero total debera de ser puesto en movimiento junto con el regimen de flujo de masa de fluido para mantener el lecho o la dispersion de particulas por largo tiempo dentro de la longitud fisica de los tubos de colector. De esta manera las particulas seran confinadas solamente en el colector y no seran arrastradas a otras partes del anillo de circulacion. Al moverse, las particulas erosionan la capa de frontera termica formada en la superficie interior del tubo, aumentando por tanto el coeficiente de transmision de calor.

  17. Simulation of a solar collector array consisting of two types of solar collectors, with and without convection barrier

    DEFF Research Database (Denmark)

    Bava, Federico; Furbo, Simon; Perers, Bengt

    2015-01-01

    The installed area of solar collectors in solar heating fields is rapidly increasing in Denmark. In this scenario even relatively small performance improvements may lead to a large increase in the overall energy production. Both collectors with and without polymer foil, functioning as convection...... barrier, can be found on the Danish market. Depending on the temperature level at which the two types of collectors operate, one can perform better than the other. This project aimed to study the behavior of a 14 solar collector row made of these two different kinds of collectors, in order to optimize...... the composition of the row. Actual solar collectors available on the Danish market (models HT-SA and HT-A 35-10 manufactured by ARCON Solar A/S) were used for this analysis. To perform the study, a simulation model in TRNSYS was developed based on the Danish solar collector field in Braedstrup. A parametric...

  18. Improved Collectors for High Power Gyrotrons

    International Nuclear Information System (INIS)

    Ives, R. Lawrence; Singh, Amarjit; Read, Michael; Borchard, Philipp; Neilson, Jeff

    2009-01-01

    High power gyrotrons are used for electron cyclotron heating, current drive and parasitic mode suppression in tokamaks for fusion energy research. These devices are crucial for successful operation of many research programs around the world, including the ITER program currently being constructed in France. Recent gyrotron failures resulted from cyclic fatigue of the copper material used to fabricated the collectors. The techniques used to collect the spent beam power is common in many gyrotrons produced around the world. There is serious concern that these tubes may also be at risk from cyclic fatigue. This program addresses the cause of the collector failure. The Phase I program successfully demonstrated feasibility of a mode of operation that eliminates the cyclic operation that caused the failure. It also demonstrated that new material can provide increased lifetime under cyclic operation that could increase the lifetime by more than on order of magnitude. The Phase II program will complete that research and develop a collector that eliminates the fatigue failures. Such a design would find application around the world.

  19. Research on Evacuation Based on Social Force Model

    Science.gov (United States)

    Liu, W.; Deng, Z.; Li, W.; Lin, J.

    2017-09-01

    Crowded centers always cause personnel casualties in evacuation operations. Stampede events often occur by hit, squeeze and crush due to panic. It is of vital important to alleviate such situation. With the deepening of personnel evacuation research, more and more researchers are committed to study individual behaviors and self-organization phenomenon in evacuation process. The study mainly includes: 1, enrich the social force model from different facets such as visual, psychological, external force to descript more realistic evacuation; 2, research on causes and effects of self - organization phenomenon. In this paper, we focus on disorder motion that occurs in the crowded indoor publics, especially the narrow channel and safety exits and other special arteries. We put forward the improved social force model to depict pedestrians' behaviors, an orderly speed-stratification evacuation method to solve disorder problem, and shape-changed export to alleviate congestion. The result of this work shows an improvement of evacuation efficiency by 19.5 %. Guiding pedestrians' direction to slow down the influence of social forces has a guidance function in improving the efficiency of indoor emergency evacuation.

  20. Syngas (CO-H2) production using high temperature micro-tubular solid oxide electrolysers

    International Nuclear Information System (INIS)

    Kleiminger, L.; Li, T.; Li, K.; Kelsall, G.H.

    2015-01-01

    Highlights: • CO 2 and/or H 2 O reduced to CO/H 2 in micro-tubular solid oxide electrolyser (MT-SOE). • MT-SOE: CO 2 , H 2 O | Ni-(ZrO 2 ) 0.92 (Y 2 O 3 ) 0.08 (YSZ) | YSZ | YSZ- La 0.8 Sr 0.2 MnO 3-δ |O 2. • −0.76 A cm −2 achieved at 1.5V and ca. 820°C for H 2 O electrolysis. • Ni wire cathode current collector gave better performance than (Ag wire+Ag paste). • C 18 O 2 in co-electrolysis could not distinguish cathodic and chemical reduction. - Abstract: CO 2 and/or H 2 O were reduced to CO/H 2 in micro-tubular solid oxide electrolysers with yttria-stabilized zirconia (YSZ) electrolyte, Ni-YSZ cermet cathode and strontium(II)-doped lanthanum manganite (LSM) oxygen-evolving anode. At 822 °C, the kinetics of CO 2 reduction were slower (ca. −0.49 A cm −2 at 1.8 V) than H 2 O reduction or co-reduction of CO 2 and H 2 O, which were comparable (ca. −0.83 to −0.77 A cm −2 at 1.8 V). Performances were improved (−0.85 and −1.1 A cm −2 for CO 2 and H 2 O electrolysis, respectively) by substituting the silver current collector with nickel and avoiding blockage of entrances to pores on the inner lumen of micro-tubes induced by silver paste applied previously to decrease contact losses. The change in current collector materials increased ohmic potential losses due to substituting the lower resistance Ag with Ni wire, but decreased electrode polarization losses by 80–93%. For co-electrolysis of CO 2 and H 2 O, isotopically-labelled C 18 O 2 was used to try to distinguish between direct cathodic reduction of CO 2 and its Ni-catalysed chemical reaction with hydrogen from reduction of steam. Unfortunately, oxygen was exchanged between C 18 O 2 and H 2 16 O, enriching oxygen-18 in the steam and substituting oxygen-16 in the carbon dioxide, so the anode off-gas isotopic fractions were meaningless. This occurred even in alumina and YSZ tubes without the micro-tubular reactor, i.e. in the absence of Ni catalyst, though not in quartz tubes

  1. An analysis of evacuation options for nuclear accidents

    Energy Technology Data Exchange (ETDEWEB)

    Tawil, J J; Strenge, D L; Schultz, R W

    1987-11-01

    The threat of release of a hazardous substance into the atmosphere will sometimes require that the population at risk be evacuated. If the substance is particularly hazardous or the release is exceptionally large, then an extensive area may have to be evacuated at substantial cost. In this report we consider the threat posed by the accidental release of radionuclides from a nuclear power plant. The report's objective is to establish relationships between radiation dose and the cost of evacuation under a wide variety of conditions. The dose can almost always be reduced by evacuating the population from a larger area. However, extending the evacuation zone outward will cause evacuation costs to increase. The purpose of this analysis was to provide the Environmental Protection Agency (EPA) a data base for evaluating whether implementation costs and risks averted could be used to justify evacuation at lower doses than would be required based on acceptable risk of health effects alone. The procedures used and results of these analyses are being made available as background information for use by others. In this report we develop cost/dose relationships for 54 scenarios that are based upon the severity of the reactor accident, meteorological conditions during the release of radionuclides into the environment, and the angular width of the evacuation zone. The 54 scenarios are derived from combinations of three accident severity levels, six meteorological conditions and evacuation zone widths of 70 deg, 90 deg, and 180 deg. Appendix tables are provided to allow acceptable evaluation of the cost/dose relationships for a wide variety of scenarios. Guidance and examples are provided in the text to show how these tables can be used.

  2. Evaluation of Test Method for Solar Collector Efficiency

    DEFF Research Database (Denmark)

    Fan, Jianhua; Shah, Louise Jivan; Furbo, Simon

    The test method of the standard EN12975-2 (European Committee for Standardization, 2004) is used by European test laboratories to determine the efficiency of solar collectors. In the test methods the mean solar collector fluid temperature in the solar collector, Tm is determined by the approximat...... and the sky temperature. Based on the investigations, recommendations for change of the test methods and test conditions are considered. The investigations are carried out within the NEGST (New Generation of Solar Thermal Systems) project financed by EU.......The test method of the standard EN12975-2 (European Committee for Standardization, 2004) is used by European test laboratories to determine the efficiency of solar collectors. In the test methods the mean solar collector fluid temperature in the solar collector, Tm is determined by the approximated...... equation where Tin is the inlet temperature to the collector and Tout is the outlet temperature from the collector. The specific heat of the solar collector fluid is in the test method as an approximation determined as a constant equal to the specific heat of the solar collector fluid at the temperature Tm...

  3. Thermal performance of a transpired solar collector updraft tower

    International Nuclear Information System (INIS)

    Eryener, Dogan; Hollick, John; Kuscu, Hilmi

    2017-01-01

    Highlights: • Transpired solar collector updraft tower has been studied experimentally. • Transpired solar collector updraft tower efficiency ranges from 60 to 80%. • A comparison has been made with other SUT prototypes. • Three times higher efficiency compared to the glazed collectors of conventional solar towers. - Abstract: A novel solar updraft tower prototype, which consists of transpired solar collector, is studied, its function principle is described and its experimental thermal performance is presented for the first time. A test unit of transpired solar collector updraft tower was installed at the campus of Trakya University Engineering Faculty in Edirne-Turkey in 2014. Solar radiation, ambient temperature, collector cavity temperatures, and chimney velocities were monitored during summer and winter period. The results showed that transpired solar collector efficiency ranges from 60% to 80%. The maximum temperature rise in the collector area is found to be 16–18 °C on the typical sunny day. Compared to conventional solar tower glazed collectors, three times higher efficiency is obtained. With increased thermal efficiency, large solar collector areas for solar towers can be reduced in half or less.

  4. Application of Catastrophe Risk Modelling to Evacuation Public Policy

    Science.gov (United States)

    Woo, G.

    2009-04-01

    The decision by civic authorities to evacuate an area threatened by a natural hazard is especially fraught when the population in harm's way is extremely large, and where there is considerable uncertainty in the spatial footprint, scale, and strike time of a hazard event. Traditionally viewed as a hazard forecasting issue, civil authorities turn to scientists for advice on a potentially imminent dangerous event. However, the level of scientific confidence varies enormously from one peril and crisis situation to another. With superior observational data, meteorological and hydrological hazards are generally better forecast than geological hazards. But even with Atlantic hurricanes, the track and intensity of a hurricane can change significantly within a few hours. This complicated and delayed the decision to call an evacuation of New Orleans when threatened by Hurricane Katrina, and would present a severe dilemma if a major hurricane were appearing to head for New York. Evacuation needs to be perceived as a risk issue, requiring the expertise of catastrophe risk modellers as well as geoscientists. Faced with evidence of a great earthquake in the Indian Ocean in December 2004, seismologists were reluctant to give a tsunami warning without more direct sea observations. Yet, from a risk perspective, the risk to coastal populations would have warranted attempts at tsunami warning, even though there was significant uncertainty in the hazard forecast, and chance of a false alarm. A systematic coherent risk-based framework for evacuation decision-making exists, which weighs the advantages of an evacuation call against the disadvantages. Implicitly and qualitatively, such a cost-benefit analysis is undertaken by civic authorities whenever an evacuation is considered. With the progress in catastrophe risk modelling, such an analysis can be made explicit and quantitative, providing a transparent audit trail for the decision process. A stochastic event set, the core of a

  5. Endoscopic burr hole evacuation of an acute subdural hematoma.

    Science.gov (United States)

    Codd, Patrick J; Venteicher, Andrew S; Agarwalla, Pankaj K; Kahle, Kristopher T; Jho, David H

    2013-12-01

    Acute subdural hematoma evacuations frequently necessitate large craniotomies with extended operative times and high relative blood loss, which can lead to additional morbidity for the patient. While endoscopic minimally invasive approaches to chronic subdural collections have been successfully demonstrated, this technique has not previously been applied to acute subdural hematomas. The authors report their experience with an 87-year-old patient presenting with a large acute right-sided subdural hematoma successfully evacuated via an endoscopic minimally invasive technique. The operative approach is outlined, and the literature on endoscopic subdural collection evacuation reviewed. Copyright © 2013. Published by Elsevier Ltd.

  6. Evacuation of children - movement on stairs and on Horizontal Plane

    DEFF Research Database (Denmark)

    Larusdottir, Aldis Run; Dederichs, Anne

    2012-01-01

    in full scale evacuation experiments where two age groups 0-2 years and 3-6 years were analyzed separately. It was found that flow through doors, walking speeds and densities were age-dependent and differed strongly from the data in existing literature. The results showed higher walking speeds in spiral...... slower in horizontal plane than adults, however they were keen to run during the evacuations, in the latter case their travel speed increased and exceeded the adults’. Since the evacuation characteristics of children differ in many ways from those of adults, nowadays models badly comprehend...

  7. Effect of form of obstacle on speed of crowd evacuation

    Science.gov (United States)

    Yano, Ryosuke

    2018-03-01

    This paper investigates the effect of the form of an obstacle on the time that a crowd takes to evacuate a room, using a toy model. Pedestrians are modeled as active soft matter moving toward a point with intended velocities. An obstacle is placed in front of the exit, and it has one of four shapes: a cylindrical column, a triangular prism, a quadratic prism, or a diamond prism. Numerical results indicate that the evacuation-completion time depends on the shape of the obstacle. Obstacles with a circular cylinder (C.C.) shape yield the shortest evacuation-completion time in the proposed model.

  8. The Variable Scale Evacuation Model (VSEM: a new tool for simulating massive evacuation processes during volcanic crises

    Directory of Open Access Journals (Sweden)

    J. M. Marrero

    2010-04-01

    Full Text Available Volcanic eruptions are among the most awesome and powerful displays of nature's force, constituting a major natural hazard for society (a single eruption can claim thousands of lives in an instant. Consequently, assessment and management of volcanic risk have become critically important goals of modern volcanology. Over recent years, numerous tools have been developed to evaluate volcanic risk and support volcanic crisis management: probabilistic analysis of future eruptions, hazard and risk maps, event trees, etc. However, there has been little improvement in the tools that may help Civil Defense officials to prepare Emergency Plans. Here we present a new tool for simulating massive evacuation processes during volcanic crisis: the Variable Scale Evacuation Model (VSEM. The main objective of the VSEM software is to optimize the evacuation process of Emergency Plans during volcanic crisis. For this, the VSEM allows the simulation of an evacuation considering different strategies depending on diverse impact scenarios. VSEM is able to calculate the required time for the complete evacuation taking into account diverse evacuation scenarios (number and type of population, infrastructure, road network, etc. and to detect high-risk or "blackspots" of the road network. The program is versatile and can work at different scales, thus being capable of simulating the evacuation of small villages as well as huge cities.

  9. Analysis and validation of a quasi-dynamic model for a solar collector field with flat plate collectors and parabolic trough collectors in series for district heating

    DEFF Research Database (Denmark)

    Tian, Zhiyong; Perers, Bengt; Furbo, Simon

    2018-01-01

    performance of the hybrid solar district heating plants is also presented. The measured and simulated results show that the integration of parabolic trough collectors in solar district heating plants can guarantee that the system produces hot water with relatively constant outlet temperature. The daily energy......A quasi-dynamic TRNSYS simulation model for a solar collector field with flat plate collectors and parabolic trough collectors in series was described and validated. A simplified method was implemented in TRNSYS in order to carry out long-term energy production analyses of the whole solar heating...... plant. The advantages of the model include faster computation with fewer resources, flexibility of different collector types in solar heating plant configuration and satisfactory accuracy in both dynamic and long-term analyses. In situ measurements were taken from a pilot solar heating plant with 5960 m...

  10. Distal renal tubular acidosis and hepatic lipidosis in a cat.

    Science.gov (United States)

    Brown, S A; Spyridakis, L K; Crowell, W A

    1986-11-15

    Clinical and laboratory evidence of hepatic failure was found in a chronically anorectic cat. Simultaneous blood and urine pH determinations established a diagnosis of distal renal tubular acidosis. The cat did not respond to treatment. Necropsy revealed distal tubular nephrosis and hepatic lipidosis. The finding of distal renal tubular acidosis in a cat with hepatic lipidosis emphasizes the importance of complete evaluation of acid-base disorders in patients.

  11. Planning for spontaneous evacuation during a radiological emergency

    International Nuclear Information System (INIS)

    Johnson, J.H. Jr.

    1984-01-01

    The Federal Emergency Management Agency's (FEMA's) radiological emergency preparedness program ignores the potential problem of spontaneous evacuation during a nuclear reactor accident. To show the importance of incorporating the emergency spatial behaviors of the population at risk in radiological emergency preparedness and response plans, this article presents empirical evidence that demonstrates the potential magnitude and geographic extent of spontaneous evacuation in the event of an accident at the Long Island Lighting Company's Shoreham Nuclear Power Station. The results indicate that, on the average, 39% of the population of Long Island is likely to evacuate spontaneously and thus to cast an evacuation shadow extending at least 25 miles beyond the plant. On the basis of these findings, necessary revisions to FEMA's radiological emergency preparedness program are outlined

  12. Teaching case studies on emergency evacuation : final report

    Science.gov (United States)

    2011-02-15

    Through the development of four Harvard Kennedy School case studies, this project explored the policy and institutional dimensions of emergency evacuation planning and implementation in two major metropolitan areas Houston and New Orleans. By pro...

  13. Rhode Island Hurricane Evacuation Study Technical Data Report

    National Research Council Canada - National Science Library

    1995-01-01

    ... evacuation decision-making. To accomplish this, the study provides information on the extent and severity of potential flooding from hurricanes, the associated vulnerable population, capacities of existing public shelters...

  14. Multi-hazard evacuation route and shelter planning for buildings.

    Science.gov (United States)

    2014-06-01

    A bi-level, two-stage, binary stochastic program with equilibrium constraints, and three variants, are presented that : support the planning and design of shelters and exits, along with hallway fortification strategies and associated : evacuation pat...

  15. Coordination of IVI and transit signal priority on transit evacuations.

    Science.gov (United States)

    2011-02-01

    During an emergency evacuation, execution time is always critical to the evacuees who are : transit dependent. Transit Signal Priority (TSP) can speed up the transit services by prioritizing : the approaching bus at a signalized intersection. With th...

  16. Evacuation decision-making at three mile island

    International Nuclear Information System (INIS)

    Zeigler, Donald. J.; Johnson, James. H.

    1987-01-01

    The accident at the Three Mile Island nuclear power plant in 1979 provoked an unanticipated and unprecedented spontaneous evacuation of people living in the area. Following the accident, revised and upgraded emergency preparedness and response regulations were issued by the Nuclear Regulatory Commission (NRC) and the Federal Emergency Management Agency. (FEMA). This includes the assumption that public education and awareness will minimise the tendency of people to evacuate spontaneously from the vicinity of an accident. This assumption is challenged. Results of an empirical test of a casual model of emergency evacuation decision-making are given. This test was devised to aid understanding of the public behaviour at the time of the Three Mile Island incident. The emergency plans for the Sizewell-B reactor are subject to brief critical consideration. It is concluded that evacuation plans need to reflect people's natural inclinations to move away from a nuclear hazard. (UK)

  17. Vesicovaginal fistula complicating uterine evacuation: a case report ...

    African Journals Online (AJOL)

    Vesicovaginal fistula complicating uterine evacuation: a case report. MA Ijaiya, AP Aboyeji, GA Fawole, AAG Jimoh, OO Alabi, AO Olarinoye, OL Akintade, OK Ogah, DNC Nwachukwu, OA Alabi, SA Esuga, ZB Ijaiya ...

  18. Modelling gastric evacuation in gadoids feeding on crustaceans

    DEFF Research Database (Denmark)

    Andersen, Niels Gerner; Chabot, Denis; Couturier, C. S.

    2016-01-01

    A mechanistic, prey surface-dependent model was expanded to describe the course and rate of gastric evacuation in predatory fishes feeding on crustacean prey with robust exoskeletons. This was accomplished by adding a layer of higher resistance to the digestive processes outside the inner softer...... parts of a prey cylinder abstraction and splitting up the prey evacuation into two stages: an initial stage where the exoskeleton is cracked and a second where the prey remains are digested and evacuated. The model was parameterized for crustaceans with different levels of armour fed to Atlantic cod...... and Chionoecetes opilio. In accordance with the apparent intraspecific isometric relationship between exoskeleton mass and total body mass, the model described stage duration and rate of evacuation of the crustacean prey independently of meal and prey sizes. The duration of the first stage increased (0-33 h...

  19. Evacuation emergency response model coupling atmospheric release advisory capability output

    International Nuclear Information System (INIS)

    Rosen, L.C.; Lawver, B.S.; Buckley, D.W.; Finn, S.P.; Swenson, J.B.

    1983-01-01

    A Federal Emergency Management Agency (FEMA) sponsored project to develop a coupled set of models between those of the Lawrence Livermore National Laboratory (LLNL) Atmospheric Release Advisory Capability (ARAC) system and candidate evacuation models is discussed herein. This report describes the ARAC system and discusses the rapid computer code developed and the coupling with ARAC output. The computer code is adapted to the use of color graphics as a means to display and convey the dynamics of an emergency evacuation. The model is applied to a specific case of an emergency evacuation of individuals surrounding the Rancho Seco Nuclear Power Plant, located approximately 25 miles southeast of Sacramento, California. The graphics available to the model user for the Rancho Seco example are displayed and noted in detail. Suggestions for future, potential improvements to the emergency evacuation model are presented

  20. Study of evacuation times based on recent accident history

    International Nuclear Information System (INIS)

    Mills, G.S.; Neuhauser, K.S.

    1995-01-01

    A key parameter in the calculation of accident dose-risks by the RADTRAN 4 code is the time assigned for evacuation of the affected area surrounding the accident. Currently, in the interest of assured conservatism, this time is set at 24 hrs. Casual anecdotal evidence has indicated that this value is overly conservative and results in assignment of overly conservative estimates of accident dose-risk. Therefore, a survey of recent truck accidents involving various hazardous materials which required evacuation of surrounding populations reported in various news media was undertaken. Accounts of pertinent scenarios were gleaned from databases citing newspapers and other periodicals, and the local authorities involved in each were contacted to get details of the evacuation including time required. This paper presents the data obtained in the study and the resultant mean evacuation time plus limits and factors influencing specific results together with conclusions regarding the appropriate value to be used in the RADTRAN 4 code

  1. Analysis of community tsunami evacuation time: An overview

    Science.gov (United States)

    Yunarto, Y.; Sari, A. M.

    2018-02-01

    Tsunami in Indonesia is defined as local tsunami due to its occurrences which are within a distance of 200 km from the epicenter of the earthquake. A local tsunami can be caused by an earthquake, landslide, or volcanic eruption. Tsunami arrival time in Indonesia is generally between 10-60 minutes. As the estimated time of the tsunami waves to reach the coast is 30 minutes after the earthquake, the community should go to the vertical or horizontal evacuation in less than 30 minutes. In an evacuation, the city frequently does the evacuation after obtaining official directions from the authorities. Otherwise, they perform an independent evacuation without correct instructions from the authorities. Both of these ways have several strengths and limitations. This study analyzes these methods regarding time as well as the number of people expected to be saved.

  2. The effect of meal size on gastric evacuation in whiting

    DEFF Research Database (Denmark)

    Andersen, Niels Gerner

    1998-01-01

    Gastric evacuation experiments were performed on whiting Merlangius merlangus fed discrete meals of different sizes. Herring Clupea harengus, sandeel Ammodytes tobianus, common goby Pomatoschistus microps, and brown shrimp Crangon crangon were tested as prey. A simple power model to describe...

  3. Empirical study on social groups in pedestrian evacuation dynamics

    Science.gov (United States)

    von Krüchten, Cornelia; Schadschneider, Andreas

    2017-06-01

    Pedestrian crowds often include social groups, i.e. pedestrians that walk together because of social relationships. They show characteristic configurations and influence the dynamics of the entire crowd. In order to investigate the impact of social groups on evacuations we performed an empirical study with pupils. Several evacuation runs with groups of different sizes and different interactions were performed. New group parameters are introduced which allow to describe the dynamics of the groups and the configuration of the group members quantitatively. The analysis shows a possible decrease of evacuation times for large groups due to self-ordering effects. Social groups can be approximated as ellipses that orientate along their direction of motion. Furthermore, explicitly cooperative behaviour among group members leads to a stronger aggregation of group members and an intermittent way of evacuation.

  4. Study of Evacuation Behavior of Coastal Gulf of Mexico Residents

    OpenAIRE

    Bhattacharjee, Sanjoy; Petrolia, Daniel R.; Hanson, Terrill R.

    2009-01-01

    In this study, we investigate the link between hurricane characteristics, demographics of the Coastal Gulf of Mexico residents, including their household location, and their respective evacuation behavior. Our study is significantly different from the previously made studies on hurricane evacuation behavior in two ways. At first, the research data is collected through recording responses to a series of hypothetical situations which are quite identical to the set of information that people are...

  5. Simulation of HPIB propagation in biased charge collector

    International Nuclear Information System (INIS)

    Li Hongyu; Qiu Aici

    2004-01-01

    A 2.5D PIC simulation using KARAT code for inner charge propagation within biased charge collector for measuring HPIB is presented. The simulation results indicate that the charges were neutralized but the current non-neutralized in the biased charge collector. The influence of ions collected vs biased voltage of the collector was also simulated. -800 V biased voltage can meet the measurement of 500 keV HPIB, and this is consistent with the experimental results

  6. TUBULAR DISORDERS WITH RICKETS-LIKE SYNDROME

    Directory of Open Access Journals (Sweden)

    N.N. Kartamysheva

    2011-01-01

    Full Text Available Often under the guise of «ordinary» Rickets are more severe kidney diseases, developing as a result of inherited or acquired, primary or secondary defects in the renal tubules. Incorrect diagnosis leads to an inadequate therapy, rapid progression of disease and renal failure. The article describes the main approaches to the diagnosis and treatment of disorders of tubular rachitis similar syndrome, presents a number of clinical cases in author's practice.Key words: tubulopathy, acidosis, electrolyte disorders, rickets, rickets-like syndrome, diagnostics, treatment, children.

  7. Fractal solutions of recirculation tubular chemical reactors

    International Nuclear Information System (INIS)

    Berezowski, Marek

    2003-01-01

    Three kinds of fractal solutions of model of recirculation non-adiabatic tubular chemical reactors are presented. The first kind concerns the structure of Feigenbaum's diagram on the limit of chaos. The second kind and the third one concern the effect of initial conditions on the dynamic solutions of models. In the course of computations two types of recirculation were considered, viz. the recirculation of mass (return of a part of products' stream) and recirculation of heat (heat exchange in the external heat exchanger)

  8. Tubular solid oxide fuel cell development program

    Energy Technology Data Exchange (ETDEWEB)

    Ray, E.R.; Cracraft, C.

    1995-12-31

    This paper presents an overview of the Westinghouse Solid Oxide Fuel Cell (SOFC) development activities and current program status. The Westinghouse goal is to develop a cost effective cell that can operate for 50,000 to 100,000 hours. Progress toward this goal will be discussed and test results presented for multiple single cell tests which have now successfully exceeded 56,000 hours of continuous power operation at temperature. Results of development efforts to reduce cost and increase power output of tubular SOFCs are described.

  9. Complex multimaterial insulating frames for windows with evacuated glazing

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Yueping; Eames, Philip C.; Hyde, Trevor J. [Centre for Sustainable Technologies, School of the Built Environment, University of Ulster, Newtownabbey, N. Ireland BT37 0QB (United Kingdom); Norton, Brian [Dublin Institute of Technology, Aungier Street, Dublin 2 (Ireland)

    2005-09-01

    The thermal performance of a complex multimaterial frame consisting of an exoskeleton framework and cavities filled with insulant materials enclosing an evacuated glazing was simulated using a two-dimensional finite element model and the results were validated experimentally using a guarded hot box calorimeter. The analysed 0.5m by 0.5m evacuated glazing consisted of two low-emittance film coated glass panes supported by an array of 0.32mm diameter pillars spaced 25mm apart, contiguously sealed by a 10mm wide metal edge seal. Thermal performance of windows employing evacuated glazing set in various complex multimaterial frames were analysed in detail. Very good agreement was found between simulations and experimental measurements of surface temperatures of the evacuated glazing window system. The heat loss from a window with an evacuated glazing and a complex multimaterial frame is about 80% of that for a window comprised of an evacuated glazing set in a single material solid frame. (author)

  10. Complex multimaterial insulating frames for windows with evacuated glazing

    Energy Technology Data Exchange (ETDEWEB)

    Yueping Fang; Eames, P.C.; Hyde, T.J. [University of Ulster, Newtonabbey (United Kingdom). Centre for Sustainable Technologies; Norton, B. [Dublin Institute of Technology, Dublin (Ireland)

    2005-09-01

    The thermal performance of a complex multimaterial frame consisting of an exoskeleton framework and cavities filled with insulant materials enclosing an evacuated glazing was simulated using a two-dimensional finite element model and the results were validated experimentally using a guarded hot box calorimeter. The analysed 0.5 m by 0.5 m evacuated glazing consisted of two low-emittance film coated glass panes supported by an array of 0.32 mm diameter pillars spaced 25 mm apart, contiguously sealed by a 10 mm wide metal edge seal. Thermal performance of windows employing evacuated glazing set in various complex multimaterial frames were analysed in detail. Very good agreement was found between simulations and experimental measurements of surface temperatures of the evacuated glazing window system. The heat loss from a window with an evacuated glazing and a complex multimaterial frame is about 80% of that for a window comprised of an evacuated glazing set in a single material solid frame. (author)

  11. Dual effects of pedestrian density on emergency evacuation

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Yi, E-mail: yima23-c@my.cityu.edu.hk [School of Transportation and Logistics, Southwest Jiaotong University, Chengdu (China); Department of Architecture and Civil Engineering, City University of Hong Kong, Kowloon (Hong Kong); Lee, Eric Wai Ming; Yuen, Richard Kwok Kit [Department of Architecture and Civil Engineering, City University of Hong Kong, Kowloon (Hong Kong)

    2017-02-05

    This paper investigates the effect of the pedestrian density in building on the evacuation dynamic with simulation method. In the simulations, both the visibility in building and the exit limit of building are taken into account. The simulation results show that the effect of the pedestrian density in building on the evacuation dynamics is dual. On the one hand, when the visibility in building is very large, the increased pedestrian density plays a negative effect. On the other hand, when the visibility in building is very small, the increased pedestrian density can play a positive effect. The simulation results also show that when both the exit width and visibility are very small, the varying of evacuation time with regard to the pedestrian density is non-monotonous and presents a U-shaped tendency. That is, in this case, too large or too small pedestrian density in building is disadvantageous to the evacuation process. Our findings provide a new insight about the effect of the pedestrian density in building on the evacuation dynamic. - Highlights: • Pedestrian density inside buildings has dual effects on evacuation. • Increased pedestrian density has a negative effect in cases of increased visibility. • Increased pedestrian density has a positive effect in cases of decreased visibility.

  12. Evacuation decision-making at Three Mile Island

    International Nuclear Information System (INIS)

    Zeigler, D.J.; Johnson, J.H. Jr.

    1987-01-01

    During the emergency at the Three Mile Island generating station in the United States, evacuation became a common adaptive response among the local population. The planning for nuclear emergencies in the US has proceeded as if there were no significant differences between nuclear and other types of disasters requiring evacuation. In the United Kingdom, emergency planning for a new generation of pressurized water reactors, about which there is legitimate safety concern, has been influenced not at all by the experience with the Three Mile Island PWR in 1979. The TMI accident has been the US's most serious experience with a nuclear plant accident and therefore is an appropriate analogy for predicting the evacuation response to future nuclear emergencies. In this light, the authors accept the need to develop models that will enable them to predict the magnitude of the evacuation shadow phenomenon around other nuclear power sites and estimate its impact on our plans to remove the threatened population from the hazard zone in the minimum amount of time. Rather than depend on education and information control to stifle evacuation response, the authors believe that evacuation plans need to build on people's natural behavioural inclinations to protect themselves in response to the nuclear hazard

  13. Tsunami evacuation mathematical model for the city of Padang

    International Nuclear Information System (INIS)

    Kusdiantara, R.; Hadianti, R.; Badri Kusuma, M. S.; Soewono, E.

    2012-01-01

    Tsunami is a series of wave trains which travels with high speed on the sea surface. This traveling wave is caused by the displacement of a large volume of water after the occurrence of an underwater earthquake or volcano eruptions. The speed of tsunami decreases when it reaches the sea shore along with the increase of its amplitudes. Two large tsunamis had occurred in the last decades in Indonesia with huge casualties and large damages. Indonesian Tsunami Early Warning System has been installed along the west coast of Sumatra. This early warning system will give about 10-15 minutes to evacuate people from high risk regions to the safe areas. Here in this paper, a mathematical model for Tsunami evacuation is presented with the city of Padang as a study case. In the model, the safe areas are chosen from the existing and selected high rise buildings, low risk region with relatively high altitude and (proposed to be built) a flyover ring road. Each gathering points are located in the radius of approximately 1 km from the ring road. The model is formulated as an optimization problem with the total normalized evacuation time as the objective function. The constraints consist of maximum allowable evacuation time in each route, maximum capacity of each safe area, and the number of people to be evacuated. The optimization problem is solved numerically using linear programming method with Matlab. Numerical results are shown for various evacuation scenarios for the city of Padang.

  14. Dual effects of pedestrian density on emergency evacuation

    International Nuclear Information System (INIS)

    Ma, Yi; Lee, Eric Wai Ming; Yuen, Richard Kwok Kit

    2017-01-01

    This paper investigates the effect of the pedestrian density in building on the evacuation dynamic with simulation method. In the simulations, both the visibility in building and the exit limit of building are taken into account. The simulation results show that the effect of the pedestrian density in building on the evacuation dynamics is dual. On the one hand, when the visibility in building is very large, the increased pedestrian density plays a negative effect. On the other hand, when the visibility in building is very small, the increased pedestrian density can play a positive effect. The simulation results also show that when both the exit width and visibility are very small, the varying of evacuation time with regard to the pedestrian density is non-monotonous and presents a U-shaped tendency. That is, in this case, too large or too small pedestrian density in building is disadvantageous to the evacuation process. Our findings provide a new insight about the effect of the pedestrian density in building on the evacuation dynamic. - Highlights: • Pedestrian density inside buildings has dual effects on evacuation. • Increased pedestrian density has a negative effect in cases of increased visibility. • Increased pedestrian density has a positive effect in cases of decreased visibility.

  15. Multi-objective evacuation routing optimization for toxic cloud releases

    International Nuclear Information System (INIS)

    Gai, Wen-mei; Deng, Yun-feng; Jiang, Zhong-an; Li, Jing; Du, Yan

    2017-01-01

    This paper develops a model for assessing the risks associated with the evacuation process in response to potential chemical accidents, based on which a multi-objective evacuation routing model for toxic cloud releases is proposed taking into account that the travel speed on each arc will be affected by disaster extension. The objectives of the evacuation routing model are to minimize travel time and individual evacuation risk along a path respectively. Two heuristic algorithms are proposed to solve the multi-objective evacuation routing model. Simulation results show the effectiveness and feasibility of the model and algorithms presented in this paper. And, the methodology with appropriate modification is suitable for supporting decisions in assessing emergency route selection in other cases (fires, nuclear accidents). - Highlights: • A model for assessing and visualizing the risks is developed. • A multi-objective evacuation routing model is proposed for toxic cloud releases. • A modified Dijkstra algorithm is designed to obtain an solution of the model. • Two heuristic algorithms have been developed as the optimization tool.

  16. Tsunami evacuation mathematical model for the city of Padang

    Energy Technology Data Exchange (ETDEWEB)

    Kusdiantara, R.; Hadianti, R.; Badri Kusuma, M. S.; Soewono, E. [Department of Mathematics Institut Teknologi Bandung, Bandung 40132 (Indonesia); Department of Civil Engineering Institut Teknologi Bandung, Bandung 40132 (Indonesia); Department of Mathematics Institut Teknologi Bandung, Bandung 40132 (Indonesia)

    2012-05-22

    Tsunami is a series of wave trains which travels with high speed on the sea surface. This traveling wave is caused by the displacement of a large volume of water after the occurrence of an underwater earthquake or volcano eruptions. The speed of tsunami decreases when it reaches the sea shore along with the increase of its amplitudes. Two large tsunamis had occurred in the last decades in Indonesia with huge casualties and large damages. Indonesian Tsunami Early Warning System has been installed along the west coast of Sumatra. This early warning system will give about 10-15 minutes to evacuate people from high risk regions to the safe areas. Here in this paper, a mathematical model for Tsunami evacuation is presented with the city of Padang as a study case. In the model, the safe areas are chosen from the existing and selected high rise buildings, low risk region with relatively high altitude and (proposed to be built) a flyover ring road. Each gathering points are located in the radius of approximately 1 km from the ring road. The model is formulated as an optimization problem with the total normalized evacuation time as the objective function. The constraints consist of maximum allowable evacuation time in each route, maximum capacity of each safe area, and the number of people to be evacuated. The optimization problem is solved numerically using linear programming method with Matlab. Numerical results are shown for various evacuation scenarios for the city of Padang.

  17. A comparison of two cloudwater/fogwater collectors: The rotating arm collector and the caltech active strand cloudwater collector

    Science.gov (United States)

    Collett, Jeffrey L.; Daube, Bruce C.; Munger, J. William; Hoffmann, Michael R.

    A side-by-side comparison of the Rotating Arm Collector (RAC) and the Caltech Active Strand Cloudwater Collector (CASCC) was conducted at an elevated coastal site near the eastern end of the Santa Barbara Channel in southern California. The CASCC was observed to collect cloudwater at rates of up to 8.5 ml min -1. The ratio of cloudwater collection rates was found to be close to the theoretical prediction of 4.2:1 (CASCC:RAC) over a wide range of liquid water contents (LWC). At low LWC, however, this ratio climbed rapidly, possibly reflecting a predominance of small droplets under these conditions, coupled with a greater collection efficiency of small droplets by the CASCC. Cloudwater samples collected by the RAC had significantly higher concentrations of Na +, Ca 2+, Mg 2+ and Cl - than those collected by the CASCC. These higher concentrations may be due to differences in the chemical composition of large vs small droplets. No significant differences were observed in concentrations of NO 3-, SO 42- or NH 4+ in samples collected by the two instruments.

  18. High Performance Flat Plate Solar Thermal Collector Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Rockenbaugh, Caleb [National Renewable Energy Lab. (NREL), Golden, CO (United States); Dean, Jesse [National Renewable Energy Lab. (NREL), Golden, CO (United States); Lovullo, David [National Renewable Energy Lab. (NREL), Golden, CO (United States); Lisell, Lars [National Renewable Energy Lab. (NREL), Golden, CO (United States); Barker, Greg [National Renewable Energy Lab. (NREL), Golden, CO (United States); Hanckock, Ed [National Renewable Energy Lab. (NREL), Golden, CO (United States); Norton, Paul [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-09-01

    This report was prepared for the General Services Administration by the National Renewable Energy Laboratory. The Honeycomb Solar Thermal Collector (HSTC) is a flat plate solar thermal collector that shows promising high efficiencies over a wide range of climate zones. The technical objectives of this study are to: 1) verify collector performance, 2) compare that performance to other market-available collectors, 3) verify overheat protection, and 4) analyze the economic performance of the HSTC both at the demonstration sites and across a matrix of climate zones and utility markets.

  19. Adaptive control of solar energy collector systems

    CERN Document Server

    Lemos, João M; Igreja, José M

    2014-01-01

    This book describes methods for adaptive control of distributed-collector solar fields: plants that collect solar energy and deliver it in thermal form. Controller design methods are presented that can overcome difficulties found in these type of plants:they are distributed-parameter systems, i.e., systems with dynamics that depend on space as well as time;their dynamics is nonlinear, with a bilinear structure;there is a significant level of uncertainty in plant knowledge.Adaptive methods form the focus of the text because of the degree of uncertainty in the knowledge of plant dynamics. Parts

  20. Tubular fluoropolymer arrays with high piezoelectric response

    Science.gov (United States)

    Zhukov, Sergey; Eder-Goy, Dagmar; Biethan, Corinna; Fedosov, Sergey; Xu, Bai-Xiang; von Seggern, Heinz

    2018-01-01

    Polymers with electrically charged internal air cavities called ferroelectrets exhibit a pronounced piezoelectric effect and are regarded as soft functional materials suitable for sensor and actuator applications. In this work, a simple method for fabricating piezoelectret arrays with open-tubular channels is introduced. A set of individual fluoroethylenepropylene (FEP) tubes is compressed between two heated metal plates. The squeezed FEP tubes are melted together at +270 °C. The resulting structure is a uniform, multi-tubular, flat array that reveals a strong piezoelectric response after a poling step. The fabricated arrays have a high ratio between piezoelectrically active and non-active areas. The optimal charging voltage and stability of the piezoelectric coefficients with pressures and frequency were experimentally investigated for two specific array structures with wall thickness of 50 and 120 μm. The array fabricated from 50 μm thick FEP tubes reveals a stable and high piezoelectric coefficient of {d}33 = 120-160 pC N-1 with a flat frequency response between 0.1 Hz and 10 kHz for pressures between 1 and 100 kPa. An increase of wall thickness to 120 μm is accompanied by a more than twofold decrease in the piezoelectric coefficient as a result of a simultaneously higher effective array stiffness and lower remanent polarization. The obtained experimental results can be used to optimize the array design with regard to the electromechanical performance.

  1. DT results of TFTR's alpha collector

    International Nuclear Information System (INIS)

    Herrmann, H.W.; Zweben, S.J.; Darrow, D.S.; Timberlake, J.R.; Macaulay-Newcombe, R.G.

    1996-01-01

    An escaping alpha collector probe has been developed for TFTR's DT phase to complement the results of the lost alpha scintillator detectors which have been operating on TFTR since 1988. Measurements of the energy distribution of escaping alphas have been made by measuring the range of alphas implanted into nickel foils located within the alpha collector. Exposed samples have been analyzed for 4 DT plasma discharges at plasma currents of 1.0 and 1.8 MA. The results at 1.0 MA are in good agreement with predictions for first orbit alpha loss at 3.5 MeV. The 1.8 MA results, however, indicate a large anomalous loss of partially thermalized alphas at an energy ∼30% below the birth energy and at a total fluence nearly an order of magnitude above expected first orbit loss. This anomalous loss is not observed with the lost alpha scintillator detectors in DT plasmas but does resemble the anomalous delayed loss seen in DD plasmas. Several potential explanations for this loss process are examined. None of the candidate explanations proposed thus far are fully consistent with the anomalous loss observations

  2. Protecting solar collector systems from corrosion

    Energy Technology Data Exchange (ETDEWEB)

    1978-01-01

    The main cause of the reduced life of a solar heating system is corrosion of the exterior parts and the internal components. This report outlines ways of reducing the cost of solar heating by reducing the corrosion in solar heating systems, and hence increasing the system's service life. Mechanisms for corrosion are discussed: these include galvanic corrosion and crevice corrosion. Means of minimizing corrosion at the design stage are then described. Such methods, when designing the solar collector, involve ensuring proper drainage of exterior water; eliminating situations where moisture, dirt and pollutants may collect; preventing condensation inside the collector; using proper gaskets and sealants at appropriate places; and selecting optimum materials and coatings. Interior corrosion can be minimized at the design stage by choosing a good heat transfer fluid and corrosion inhibitor, in the case of systems where liquids are used; ensuring a low enough flow rate to avoid erosion; designing the system to avoid crevices; and avoiding situations where galvanic corrosion could occur. Other procedures are given for minimizing corrosion in the construction and operation of solar heating systems. 7 figs., 7 tabs.

  3. Artificial Neural Networks-Based Software for Measuring Heat Collection Rate and Heat Loss Coefficient of Water-in-Glass Evacuated Tube Solar Water Heaters

    Science.gov (United States)

    Liu, Zhijian; Liu, Kejun; Li, Hao; Zhang, Xinyu; Jin, Guangya; Cheng, Kewei

    2015-01-01

    Measurements of heat collection rate and heat loss coefficient are crucial for the evaluation of in service water-in-glass evacuated tube solar water heaters. However, conventional measurement requires expensive detection devices and undergoes a series of complicated procedures. To simplify the measurement and reduce the cost, software based on artificial neural networks for measuring heat collection rate and heat loss coefficient of water-in-glass evacuated tube solar water heaters was developed. Using multilayer feed-forward neural networks with back-propagation algorithm, we developed and tested our program on the basis of 915measuredsamples of water-in-glass evacuated tube solar water heaters. This artificial neural networks-based software program automatically obtained accurate heat collection rateand heat loss coefficient using simply "portable test instruments" acquired parameters, including tube length, number of tubes, tube center distance, heat water mass in tank, collector area, angle between tubes and ground and final temperature. Our results show that this software (on both personal computer and Android platforms) is efficient and convenient to predict the heat collection rate and heat loss coefficient due to it slow root mean square errors in prediction. The software now can be downloaded from http://t.cn/RLPKF08. PMID:26624613

  4. Artificial Neural Networks-Based Software for Measuring Heat Collection Rate and Heat Loss Coefficient of Water-in-Glass Evacuated Tube Solar Water Heaters.

    Science.gov (United States)

    Liu, Zhijian; Liu, Kejun; Li, Hao; Zhang, Xinyu; Jin, Guangya; Cheng, Kewei

    2015-01-01

    Measurements of heat collection rate and heat loss coefficient are crucial for the evaluation of in service water-in-glass evacuated tube solar water heaters. However, conventional measurement requires expensive detection devices and undergoes a series of complicated procedures. To simplify the measurement and reduce the cost, software based on artificial neural networks for measuring heat collection rate and heat loss coefficient of water-in-glass evacuated tube solar water heaters was developed. Using multilayer feed-forward neural networks with back-propagation algorithm, we developed and tested our program on the basis of 915 measured samples of water-in-glass evacuated tube solar water heaters. This artificial neural networks-based software program automatically obtained accurate heat collection rate and heat loss coefficient using simply "portable test instruments" acquired parameters, including tube length, number of tubes, tube center distance, heat water mass in tank, collector area, angle between tubes and ground and final temperature. Our results show that this software (on both personal computer and Android platforms) is efficient and convenient to predict the heat collection rate and heat loss coefficient due to it slow root mean square errors in prediction. The software now can be downloaded from http://t.cn/RLPKF08.

  5. Social influence on evacuation behavior in real and virtual environments

    Directory of Open Access Journals (Sweden)

    Max Kinateder

    2016-07-01

    Full Text Available Virtual reality (VR is a promising tool to study evacuation behavior as it allows experimentally controlled, safe simulation of otherwise dangerous situations. However, validation studies comparing evacuation behavior in real and virtual environments are still scarce. We compare the decision to evacuate in response to a fire alarm in matched physical and virtual environments. 150 participants were tested individually in a one-trial experiment in one of three conditions. In the Control condition, the fire alarm sounded while the participant performed a bogus perceptual matching task. In the Passive bystander condition, the participant performed the task together with a confederate who ignored the fire alarm. In the Active bystander condition, the confederate left the room when the fire alarm went off. Half of the participants in each condition experienced the scenario in the real laboratory, and the other half in a matched virtual environment with a virtual bystander, presented in a head-mounted display. The active bystander group was more likely to evacuate, and the passive bystander group less likely to evacuate, than the control group. This pattern of social influence was observed in both the real and virtual environments, although the overall response to the virtual alarm was reduced; positive influence was comparable, whereas negative influence was weaker in VR. We found no reliable gender effects for the participant or the bystander. These findings extend the bystander effect to the decision to evacuate, revealing a positive as well as the previous negative social influence. The results support the ecological validity of VR as a research tool to study evacuation behavior in emergency situations, with the caveat that effect sizes may be smaller in VR.

  6. Agent-based Modeling with MATSim for Hazards Evacuation Planning

    Science.gov (United States)

    Jones, J. M.; Ng, P.; Henry, K.; Peters, J.; Wood, N. J.

    2015-12-01

    Hazard evacuation planning requires robust modeling tools and techniques, such as least cost distance or agent-based modeling, to gain an understanding of a community's potential to reach safety before event (e.g. tsunami) arrival. Least cost distance modeling provides a static view of the evacuation landscape with an estimate of travel times to safety from each location in the hazard space. With this information, practitioners can assess a community's overall ability for timely evacuation. More information may be needed if evacuee congestion creates bottlenecks in the flow patterns. Dynamic movement patterns are best explored with agent-based models that simulate movement of and interaction between individual agents as evacuees through the hazard space, reacting to potential congestion areas along the evacuation route. The multi-agent transport simulation model MATSim is an agent-based modeling framework that can be applied to hazard evacuation planning. Developed jointly by universities in Switzerland and Germany, MATSim is open-source software written in Java and freely available for modification or enhancement. We successfully used MATSim to illustrate tsunami evacuation challenges in two island communities in California, USA, that are impacted by limited escape routes. However, working with MATSim's data preparation, simulation, and visualization modules in an integrated development environment requires a significant investment of time to develop the software expertise to link the modules and run a simulation. To facilitate our evacuation research, we packaged the MATSim modules into a single application tailored to the needs of the hazards community. By exposing the modeling parameters of interest to researchers in an intuitive user interface and hiding the software complexities, we bring agent-based modeling closer to practitioners and provide access to the powerful visual and analytic information that this modeling can provide.

  7. Rectosigmoid tubular duplication presenting as perineal sepsis in a neonate.

    Science.gov (United States)

    Zhang, Zhibo; Huang, Ying; Wang, Dajia; Su, Pengjun

    2010-03-01

    Tubular rectal duplication is a very rare congenital anomaly. We report a case of tubular rectal duplication in a newborn baby who presented with perianal sepsis. The diagnosis was confirmed by barium enema, magnetic resonance imaging, and at operation. We performed total mucosectomy through a posterior sagittal incision combined with laparotomy. The patient was doing quite well at 17-month follow-up examination.

  8. Cyclosporine A induces senescence in renal tubular epithelial cells

    NARCIS (Netherlands)

    Jennings, Paul; Koppelstaetter, Christian; Aydin, Sonia; Abberger, Thomas; Wolf, Anna Maria; Mayer, Gert; Pfaller, Walter

    The nephrotoxic potential of the widely used immunosuppressive agent cyclosporine A (CsA) is well recognized. However, the mechanism of renal tubular toxicity is not yet fully elucidated. Chronic CsA nephropathy and renal organ aging share some clinical features, such as renal fibrosis and tubular

  9. Intrarenal purinergic signaling in the control of renal tubular transport

    DEFF Research Database (Denmark)

    Prætorius, Helle; Leipziger, Jens Georg

    2010-01-01

    -reaching advances indicate that ATP is often used as a local transmitter for classical sensory transduction. This transmission apparently also applies to sensory functions in the kidney. Locally released ATP is involved in sensing of renal tubular flow or in detecting the distal tubular load of NaCl at the macula...

  10. Physically absorbable reagents-collectors in elementary flotation

    Energy Technology Data Exchange (ETDEWEB)

    S.A. Kondrat' ev; I.G. Bochkarev [Russian Academy of Sciences, Novosibirsk (Russian Federation). Institute of Mining

    2007-09-15

    Based on the reviewed researches held at the Institute of Mining, Siberian Branch, Russian Academy of Sciences, the effect of physically absorbable reagents-collectors on formation of a flotation complex and its stability in turbulent pulp flows in flotation machines of basic types is considered. The basic requirements for physically absorbable reagents-collectors at different flotation stages are established.

  11. Preliminary design package for solar collector and solar pump

    Science.gov (United States)

    1978-01-01

    A solar-operated pump using an existing solar collector, for use on solar heating and cooling and hot water systems is described. Preliminary design criteria of the collector and solar-powered pump is given including: design drawings, verification plans, and hazard analysis.

  12. ANALYSIS AND MODELING OF SOLAR EVAPORATOR-COLLECTOR

    Directory of Open Access Journals (Sweden)

    Zakaria Mohd. Amin

    2015-11-01

    Full Text Available Solar energy is considered a sustainable resource that poses little to no harmful effects on the environment. The performance of a solar system depends to a great extent on the collector used for the conversion of solar radiant energy to thermal energy. A solar evaporator-collector (SEC is basically an unglazed flat plate collector where refrigerants, such as R134a is used as the working fluid. As the operating temperature of the SEC is very low, it utilizes both solar irradiation and ambient energy leading to a much higher efficiency than the conventional collectors. This capability of SECs to utilize ambient energy also enables the system to operate at night. This type of collector can be locally made and is relatively much cheaper than the conventional collector.   At the National University of Singapore, the evaporator-collector was integrated to a heat pump and the performance was investigated for several thermal applications: (i water heating, (ii drying and (iii desalination. A 2-dimensional transient mathematical model of this system was developed and validated by experimental data. The present study provides a comprehensive study of performance. KEYWORDS: heat pump; evaporator-collector.

  13. Efficiency improvement of flat plate solar collector using reflector

    Directory of Open Access Journals (Sweden)

    Himangshu Bhowmik

    2017-11-01

    Full Text Available Solar collectors are the main components of a solar heating system. The collectors collect the sun’s energy, transform this radiation into heat, and then transfer this heat into a fluid, water or air, which has many household or industrial applications. This paper introduces a new technology to improve the performance of the solar thermal collectors. The solar reflector used here with the solar collector to increase the reflectivity of the collector. Thus, the reflector concentrates both direct and diffuse radiation of the sun toward the collector. To maximize the intensity of incident radiation, the reflector was allowed to change its angle with daytime. The radiations coming from the sun’s energy were converted into heat, and then this heat was transferred to the collector fluid, water. A prototype of a solar water heating system was constructed and obtained the improvement of the collector efficiency around 10% by using the reflector. Thus, the present solar water heating systems having the best thermal performance compared to the available systems.

  14. Direct-heating solar-collector dump valve

    Science.gov (United States)

    Howikman, T. C.

    1977-01-01

    Five-port ganged valve isolates collector from primary load system pressure and drains collectors, allowing use of direct heating with all its advantages. Valve is opened and closed by same switch that controls pump or by temperature sensor set at O C, while providing direct dump option.

  15. Diagnostics of defeats of venous collectors of brain

    International Nuclear Information System (INIS)

    Timofeeva, T.V.; Polunina, I.S.; Shcherbakova, E.Ya.; Kuldakova, S.V.

    1997-01-01

    Comparative data of transcranial ultrasonic dopplerography (170 patients) and radionuclidous antroscintigraphy (124), received during diagnostics of defects of venous collectors of brain are analyzed. Five variants of defeats of venous collectors (cross, sigmoid, internal of jugular of jugular vein), but also unpaired sine (direct, confluent) are described. Received results permit to reveal interrelation of infringements of venous outflow and increase of intracranial pressure

  16. Advances in design of air-heating collectors

    CSIR Research Space (South Africa)

    Johannsen, A

    1982-11-01

    Full Text Available Principles of the operation of air-heating collectors are discussed. The fundamental differences between the design principles of air-heating as opposed to water-heating collectors are highlighted. The main requirement is the transfer of heat from...

  17. Thermal performances of vertical hybrid PV/T air collector

    Science.gov (United States)

    Tabet, I.; Touafek, K.; Bellel, N.; Khelifa, A.

    2016-11-01

    In this work, numerical analyses and the experimental validation of the thermal behavior of a vertical photovoltaic thermal air collector are investigated. The thermal model is developed using the energy balance equations of the PV/T air collector. Experimental tests are conducted to validate our mathematical model. The tests are performed in the southern Algerian region (Ghardaïa) under clear sky conditions. The prototype of the PV/T air collector is vertically erected and south oriented. The absorber upper plate temperature, glass cover temperature, air temperature in the inlet and outlet of the collector, ambient temperature, wind speed, and solar radiation are measured. The efficiency of the collector increases with increase in mass flow of air, but the increase in mass flow of air reduces the temperature of the system. The increase in efficiency of the PV/T air collector is due to the increase in the number of fins added. In the experiments, the air temperature difference between the inlet and the outlet of the PV/T air collector reaches 10 ° C on November 21, 2014, the interval time is between 10:00 and 14:00, and the temperature of the upper plate reaches 45 ° C at noon. The mathematical model describing the dynamic behavior of the typical PV/T air collector is evaluated by calculating the root mean square error and mean absolute percentage error. A good agreement between the experiment and the simulation results is obtained.

  18. A study of the flat plate solar collector in Guinea

    International Nuclear Information System (INIS)

    Boye Barry, M.

    1990-12-01

    In this paper, we study a collector, made by cheap local materials (wood, aluminium, etc.), and prepared in the carpenteries, and in the mechanic work rooms with a simple technology. The efficiency of our collector is compared with several variants made in other countries. (author). 9 refs, 6 figs, 2 tabs

  19. Annual measured and simulated thermal performance analysis of a hybrid solar district heating plant with flat plate collectors and parabolic trough collectors in series

    DEFF Research Database (Denmark)

    Tian, Zhiyong; Perers, Bengt; Furbo, Simon

    2017-01-01

    Flat plate collectors have relatively low efficiency at the typical supply temperatures of district heating networks (70–95 °C). Parabolic trough collectors retain their high efficiency at these temperatures. To maximize the advantages of flat plate collectors and parabolic trough collectors in l...... for this type of hybrid solar district heating plants with flat plate collectors and parabolic trough collectors in the Nordic region, but also introduce a novel design concept of solar district heating plants to other high solar radiation areas....... in large solar heating plants for a district heating network, a hybrid solar collector field with 5960 m2 flat plate collectors and 4039 m2 parabolic trough collectors in series was constructed in Taars, Denmark. The design principle is that the flat plate collectors preheat the return water from...

  20. Resident perception of volcanic hazards and evacuation procedures

    Directory of Open Access Journals (Sweden)

    D. K. Bird

    2009-02-01

    Full Text Available Katla volcano, located beneath the Mýrdalsjökull ice cap in southern Iceland, is capable of producing catastrophic jökulhlaup. The Icelandic Civil Protection (ICP, in conjunction with scientists, local police and emergency managers, developed mitigation strategies for possible jökulhlaup produced during future Katla eruptions. These strategies were tested during a full-scale evacuation exercise in March 2006. A positive public response during a volcanic crisis not only depends upon the public's knowledge of the evacuation plan but also their knowledge and perception of the possible hazards. To improve the effectiveness of residents' compliance with warning and evacuation messages it is important that emergency management officials understand how the public interpret their situation in relation to volcanic hazards and their potential response during a crisis and apply this information to the ongoing development of risk mitigation strategies. We adopted a mixed methods approach in order to gain a broad understanding of residents' knowledge and perception of the Katla volcano in general, jökulhlaup hazards specifically and the regional emergency evacuation plan. This entailed field observations during the major evacuation exercise, interviews with key emergency management officials and questionnaire survey interviews with local residents. Our survey shows that despite living within the hazard zone, many residents do not perceive that their homes could be affected by a jökulhlaup, and many participants who perceive that their homes are safe, stated that they would not evacuate if an evacuation warning was issued. Alarmingly, most participants did not receive an evacuation message during the exercise. However, the majority of participants who took part in the exercise were positive about its implementation. This assessment of resident knowledge and perception of volcanic hazards and the evacuation plan is the first of its kind in

  1. Selective flotation of phosphate minerals with hydroxamate collectors

    Science.gov (United States)

    Miller, Jan D.; Wang, Xuming; Li, Minhua

    2002-01-01

    A method is disclosed for separating phosphate minerals from a mineral mixture, particularly from high-dolomite containing phosphate ores. The method involves conditioning the mineral mixture by contacting in an aqueous in environment with a collector in an amount sufficient for promoting flotation of phosphate minerals. The collector is a hydroxamate compound of the formula; ##STR1## wherein R is generally hydrophobic and chosen such that the collector has solubility or dispersion properties it can be distributed in the mineral mixture, typically an alkyl, aryl, or alkylaryl group having 6 to 18 carbon atoms. M is a cation, typically hydrogen, an alkali metal or an alkaline earth metal. Preferably, the collector also comprises an alcohol of the formula, R'--OH wherein R' is generally hydrophobic and chosen such that the collector has solubility or dispersion properties so that it can be distributed in the mineral mixture, typically an alkyl, aryl, or alkylaryl group having 6 to 18 carbon atoms.

  2. A solar air collector with integrated latent heat thermal storage

    Directory of Open Access Journals (Sweden)

    Klimes Lubomir

    2012-04-01

    Full Text Available Simulations of the behaviour of a solar air collector with integrated latent heat thermal storage were performed. The model of the collector was created with the use of coupling between TRNSYS 17 and MATLAB. Latent heat storage (Phase Change Material - PCM was integrated with the solar absorber. The model of the latent heat storage absorber was created in MATLAB and the model of the solar air collector itself was created in TRNSYS with the use of TYPE 56. The model of the latent heat storage absorber allows specification of the PCM properties as well as other parameters. The simulated air collector was the front and back pass collector with the absorber in the middle of the air cavity. Two variants were considered for comparison; the light-weight absorber made of sheet metal and the heat-storage absorber with the PCM. Simulations were performed for the climatic conditions of the Czech Republic (using TMY weather data.

  3. Analysis of a solar collector field water flow network

    Science.gov (United States)

    Rohde, J. E.; Knoll, R. H.

    1976-01-01

    A number of methods are presented for minimizing the water flow variation in the solar collector field for the Solar Building Test Facility at the Langley Research Center. The solar collector field investigated consisted of collector panels connected in parallel between inlet and exit collector manifolds to form 12 rows. The rows were in turn connected in parallel between the main inlet and exit field manifolds to complete the field. The various solutions considered included various size manifolds, manifold area change, different locations for the inlets and exits to the manifolds, and orifices or flow control valves. Calculations showed that flow variations of less than 5 percent were obtainable both inside a row between solar collector panels and between various rows.

  4. Thermal analysis of gyrotron traveling-wave tube collector

    International Nuclear Information System (INIS)

    Zheng Zhiqing; Luo Yong; Jiang Wei; Tang Yong

    2013-01-01

    In order to solve cooling problem of the gyrotron traveling-wave tube(TWT) collector and guarantee the gyrotron TWT's reliability and stability, the electron trajectories in the gyrotron TWT are simulated using CST electron simulation software. Thermal analysis of the collector with finite element software ANSYS is performed. The ways of applying boundary that affects the distribution of collector temperature are compared. The influence of the water temperature and flow rate on collector temperature distribution under actual heat fluxes (boundary condition) is researched. The size and number of collector fins are optimized, and a relatively perfect structure is obtained finally. The result estimated by simulation is consistent with the experiment and proves that the model and method employed in this work are suitable. (authors)

  5. Mathematical modelling of unglazed solar collectors under extreme operating conditions

    DEFF Research Database (Denmark)

    Bunea, M.; Perers, Bengt; Eicher, S.

    2015-01-01

    average temperature levels at the evaporator. Simulation of these systems requires a collector model that can take into account operation at very low temperatures (below freezing) and under various weather conditions, particularly operation without solar irradiation.A solar collector mathematical model......Combined heat pumps and solar collectors got a renewed interest on the heating system market worldwide. Connected to the heat pump evaporator, unglazed solar collectors can considerably increase their efficiency, but they also raise the coefficient of performance of the heat pump with higher...... was found due to the condensation phenomenon and up to 40% due to frost under no solar irradiation. This work also points out the influence of the operating conditions on the collector's characteristics.Based on experiments carried out at a test facility, every heat flux on the absorber was separately...

  6. Test results, Industrial Solar Technology parabolic trough solar collector

    Energy Technology Data Exchange (ETDEWEB)

    Dudley, V.E. [EG and G MSI, Albuquerque, NM (United States); Evans, L.R.; Matthews, C.W. [Sandia National Labs., Albuquerque, NM (United States)

    1995-11-01

    Sandia National Laboratories and Industrial Solar Technology are cost-sharing development of advanced parabolic trough technology. As part of this effort, several configurations of an IST solar collector were tested to determine the collector efficiency and thermal losses with black chrome and black nickel receiver selective coatings, combined with aluminized film and silver film reflectors, using standard Pyrex{reg_sign} and anti-reflective coated Pyrex{reg_sign} glass receiver envelopes. The development effort has been successful, producing an advanced collector with 77% optical efficiency, using silver-film reflectors, a black nickel receiver coating, and a solgel anti-reflective glass receiver envelope. For each receiver configuration, performance equations were empirically derived relating collector efficiency and thermal losses to the operating temperature. Finally, equations were derived showing collector performance as a function of input insolation value, incident angle, and operating temperature.

  7. Project 'Colored solar collectors' - Annual report 2005

    Energy Technology Data Exchange (ETDEWEB)

    Schueler, A.; Chambrier, E. De; Roecker, Ch.; Scartezzini, J. -L.

    2005-12-15

    The architectural integration of thermal solar collectors into buildings is often limited by their black color, and the visibility of tubes and corrugations of the absorber sheets. A certain freedom in color choice would be desirable, but the colored appearance should not cause excessive performance degradation. Multilayered thin film interference filters on the collector glazing can produce a colored reflection, hiding the corrugated metal sheet, while transmitting the non-reflected radiation entirely to the absorber. These interference filters are designed and optimized by numerical simulation and shall be manufactured by the sol-gel dip-coating process. The proposed colored glazed solar collectors will be ideally suited for architectural integration into buildings, e.g. as solar active glass facades. The availability of thin film materials with a refractive index lower than that of silicon favors a higher solar transmission at a given value of visible reflectance. The feasibility of the sol-gel deposition of such low refractive index materials has been demonstrated. For the development of nanostructured materials, analytical methods such as electron microscopy are extremely helpful. Important techniques of substrate pretreatment, sample cleaving, polishing, mounting, and microscope handling have been acquired. First measurements yield images of nanostructures produced by the sol-gel dip-coating process. Nanocomposite Ti{sub x}Si{sub 1-x}O{sub 2} thin films provide a large range of refractive indices. Aiming a high efficiency of the colored reflection, Ti{sub x}Si{sub 1-x}O{sub 2} based multilayered coatings have been designed and subsequently prepared by sol-gel dip-coating. The energy efficiency M = R{sub VIS}/(100%-T{sub sol}) of the obtained colored reflection amounts up to 2.4. For a convincing demonstration sufficiently large samples of high quality are imperatively needed. An infrastructure for the handling of A4 sized samples has been established

  8. A Simple Evacuation Modeling and Simulation Tool for First Responders

    Energy Technology Data Exchange (ETDEWEB)

    Koch, Daniel B [ORNL; Payne, Patricia W [ORNL

    2015-01-01

    Although modeling and simulation of mass evacuations during a natural or man-made disaster is an on-going and vigorous area of study, tool adoption by front-line first responders is uneven. Some of the factors that account for this situation include cost and complexity of the software. For several years, Oak Ridge National Laboratory has been actively developing the free Incident Management Preparedness and Coordination Toolkit (IMPACT) to address these issues. One of the components of IMPACT is a multi-agent simulation module for area-based and path-based evacuations. The user interface is designed so that anyone familiar with typical computer drawing tools can quickly author a geospatially-correct evacuation visualization suitable for table-top exercises. Since IMPACT is designed for use in the field where network communications may not be available, quick on-site evacuation alternatives can be evaluated to keep pace with a fluid threat situation. Realism is enhanced by incorporating collision avoidance into the simulation. Statistics are gathered as the simulation unfolds, including most importantly time-to-evacuate, to help first responders choose the best course of action.

  9. Dual effects of pedestrian density on emergency evacuation

    Science.gov (United States)

    Ma, Yi; Lee, Eric Wai Ming; Yuen, Richard Kwok Kit

    2017-02-01

    This paper investigates the effect of the pedestrian density in building on the evacuation dynamic with simulation method. In the simulations, both the visibility in building and the exit limit of building are taken into account. The simulation results show that the effect of the pedestrian density in building on the evacuation dynamics is dual. On the one hand, when the visibility in building is very large, the increased pedestrian density plays a negative effect. On the other hand, when the visibility in building is very small, the increased pedestrian density can play a positive effect. The simulation results also show that when both the exit width and visibility are very small, the varying of evacuation time with regard to the pedestrian density is non-monotonous and presents a U-shaped tendency. That is, in this case, too large or too small pedestrian density in building is disadvantageous to the evacuation process. Our findings provide a new insight about the effect of the pedestrian density in building on the evacuation dynamic.

  10. Pedestrian evacuation at the subway station under fire

    Science.gov (United States)

    Xiao-Xia, Yang; Hai-Rong, Dong; Xiu-Ming, Yao; Xu-Bin, Sun

    2016-04-01

    With the development of urban rail transit, ensuring the safe evacuation of pedestrians at subway stations has become an important issue in the case of an emergency such as a fire. This paper chooses the platform of line 4 at the Beijing Xuanwumen subway station to study the emergency evacuation process under fire. Based on the established platform, effects of the fire dynamics, different initial pedestrian densities, and positions of fire on evacuation are investigated. According to simulation results, it is found that the fire increases the air temperature and the smoke density, and decreases pedestrians’ visibility and walking velocity. Also, there is a critical initial density at the platform if achieving a safe evacuation within the required 6 minutes. Furthermore, different positions of fire set in this paper have little difference on crowd evacuation if the fire is not large enough. The suggestions provided in this paper are helpful for the subway operators to prevent major casualties. Project supported by the National Natural Science Foundation of China (Grant Nos. 61322307 and 61233001).

  11. Fluid Line Evacuation and Freezing Experiments for Digital Radiator Concept

    Science.gov (United States)

    Berisford, Daniel F.; Birur, Gajanana C.; Miller, Jennifer R.; Sunada, Eric T.; Ganapathi, Gani B.; Stephan, Ryan; Johnson, Mark

    2011-01-01

    The digital radiator technology is one of three variable heat rejection technologies being investigated for future human-rated NASA missions. The digital radiator concept is based on a mechanically pumped fluid loop with parallel tubes carrying coolant to reject heat from the radiator surface. A series of valves actuate to start and stop fluid flow to di erent combinations of tubes, in order to vary the heat rejection capability of the radiator by a factor of 10 or more. When the flow in a particular leg is stopped, the fluid temperature drops and the fluid can freeze, causing damage or preventing flow from restarting. For this reason, the liquid in a stopped leg must be partially or fully evacuated upon shutdown. One of the challenges facing fluid evacuation from closed tubes arises from the vapor generated during pumping to low pressure, which can cause pump cavitation and incomplete evacuation. Here we present a series of laboratory experiments demonstrating fluid evacuation techniques to overcome these challenges by applying heat and pumping to partial vacuum. Also presented are results from qualitative testing of the freezing characteristics of several different candidate fluids, which demonstrate significant di erences in freezing properties, and give insight to the evacuation process.

  12. Forming of Polymeric Tubular Micro-components

    DEFF Research Database (Denmark)

    Qin, Yi; Zhao, Jie; Anyasodor, Gerald

    2015-01-01

    platform for the production of functional polymeric tubular micro-components. The chapter gives background on the current market and process development trends, followed by description of materials, process configuration, tool design and machine development for each processing technology as well......This chapter is intended to provide an overview of three nontraditional shaping technologies for the forming of polymeric micro-tubes, which are hot embossing, blow molding, and cross rolling, as well as realization of a process chain and the integration of a modular machine-based manufacturing...... as strategy for integration of the technologies and equipment into a common platform. Finally, potential applications of the technologies and facilities developed are highlighted....

  13. Sunscope natural light systems : tubular skylights

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    This brochure described a tubular skylight designed by Sunscope Natural Light Systems. The Sunscope is a super-reflective light system in which daylight is reflected down a cylinder to a translucent ceiling fixture that diffuses natural light throughout the room in which it is placed. The Sunscope requires no structure changes, is installed in less than 3 hours, and requires no drywall repairs or repainting. The system eliminates the need for daytime electric lighting, and causes no winter heat losses or summer heat gains. Available in 3 sizes, the Sunscope has no moving parts and is fully maintenance-free. The system was designed for use in commercial and residential applications. 7 figs.

  14. Inherited renal tubular defects with hypokalemia

    Directory of Open Access Journals (Sweden)

    Muthukrishnan J

    2009-01-01

    Full Text Available Bartter′s and Gitelman′s syndrome are two ends of a spectrum of inherited renal tubular disorders that present with hypokalemic metabolic alkalosis of varying severity. Clinical features and associated calcium and magnesium ion abnormalities are used to diagnose these cases after excluding other commoner causes. We report on two cases, the first being a young boy, born of pregnancy complicated by polyhydramnios, who had classical dysmorphic features, polyuria, hypokalemia and hypercalciuria and was diagnosed as having Bartter′s syndrome. The second patient is a lady who had recurrent tetany as the only manifestation of Gitelman′s syndrome, which is an unusual presentation. Potassium replacement with supplementation of other deficient ions led to satisfactory clinical and biochemical response.

  15. An ultrasonic inspection tool for production tubulars

    Energy Technology Data Exchange (ETDEWEB)

    Newton, K; Martin, R; Ravenscroft, F [AEA Technology, Harwell (United Kingdom)

    1994-06-01

    Advances in ultrasonic technology, high temperature techniques and remote processing power are enabling a new generation of inspection tools to be developed. This paper describes a particular new ultrasonic caliper system, developed by AEA Technology, with the aim of providing improved information about the condition of production tubulars of oil and gas wells. The system is designed to provide enhanced surface area coverage compared to the current devices, which are typically mechanical 'finger' calipers. It also provides a non-contacting measure of corrosion and wear together with direct on-line output and automated data analysis. The new tool is designed to operate in oil and gas, vertical or deviated wells and has the potential for modification to inspect small diameter pipes in topside or other plant. (author)

  16. Cytocompatibility of a silk fibroin tubular scaffold

    International Nuclear Information System (INIS)

    Wang, Jiannan; Wei, Yali; Yi, Honggen; Liu, Zhiwu; Sun, Dan; Zhao, Huanrong

    2014-01-01

    Regenerated silk fibroin (SF) materials are increasingly used for tissue engineering applications. In order to explore the feasibility of a novel biomimetic silk fibroin tubular scaffold (SFTS) crosslinked by poly(ethylene glycol) diglycidyl ether (PEG-DE), biocompatibility with cells was evaluated. The novel biomimetic design of the SFTS consisted of three distinct layers: a regenerated SF intima, a silk braided media and a regenerated SF adventitia. The SFTS exhibited even silk fibroin penetration throughout the braid, forming a porous layered tube with superior mechanical, permeable and cell adhesion properties that are beneficial to vascular regeneration. Cytotoxicity and cell compatibility were tested on L929 cells and human umbilical vein endothelial cells (EA.hy926). DNA content analysis, scanning electron and confocal microscopies and MTT assay showed no inhibitory effects on DNA replication. Cell morphology, viability and proliferation were good for L929 cells, and satisfactory for EA.hy926 cells. Furthermore, the suture retention strength of the SFTS was about 23 N and the Young's modulus was 0.2–0.3 MPa. Collectively, these data demonstrate that PEG-DE crosslinked SFTS possesses the appropriate cytocompatibility and mechanical properties for use as vascular scaffolds as an alternative to vascular autografts. - Highlights: • A PEG-DE cross-linked small caliber porous silk fibroin tubular scaffold (SFTS) • PEG-DE cross-linked SF film had no inhibitory effect on DNA replication of cells. • Cells cultured on the SFTS showed good morphology, cell viability and proliferative activity. • SFTS would be beneficial to endothelialization. • SFTS had good suture retention strength and flexibility

  17. Analysis of WWER 1000 collector cracking mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Matocha, K.; Wozniak, J. [Vitkovice J.S.C., Ostrava (Switzerland)

    1997-12-31

    The presentation reviews the large experimental program, started in 1993 in Vitkovice, where the main aim was: (1) a detailed study of strain and thermal ageing, dissolved oxygen content and temperature on subcritical crack growth in 10NiMo8.5 (10GN2MFA) steel, (2) a detailed study of the effect of high temperature water and tube expansion technology on fracture behaviour of ligaments between holes for heat exchange tubes, and (3) a detailed study of the effect of drilling, tube expansion technology and heat treatment on residual stresses on the surface of holes for heat exchange tubes. The aim of all these investigations was to find a dominant damage mechanism responsible for collector cracking to be able to judge the efficiency of implemented modifications and suggested countermeasures and to answer a very important question whether proper operation conditions (mainly water chemistry) make the operation of steam generators made in Vitcovice safe throughout the planned lifetime. 10 refs.

  18. Analysis of WWER 1000 collector cracking mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Matocha, K; Wozniak, J [Vitkovice J.S.C., Ostrava (Switzerland)

    1998-12-31

    The presentation reviews the large experimental program, started in 1993 in Vitkovice, where the main aim was: (1) a detailed study of strain and thermal ageing, dissolved oxygen content and temperature on subcritical crack growth in 10NiMo8.5 (10GN2MFA) steel, (2) a detailed study of the effect of high temperature water and tube expansion technology on fracture behaviour of ligaments between holes for heat exchange tubes, and (3) a detailed study of the effect of drilling, tube expansion technology and heat treatment on residual stresses on the surface of holes for heat exchange tubes. The aim of all these investigations was to find a dominant damage mechanism responsible for collector cracking to be able to judge the efficiency of implemented modifications and suggested countermeasures and to answer a very important question whether proper operation conditions (mainly water chemistry) make the operation of steam generators made in Vitcovice safe throughout the planned lifetime. 10 refs.

  19. Study of Cylindrical Honeycomb Solar Collector

    Directory of Open Access Journals (Sweden)

    Atish Mozumder

    2014-01-01

    Full Text Available We present the results of our investigation on cylindrical honeycomb solar collector. The honeycomb has been fabricated with transparent cellulose triacetate polymer sheets. Insulation characteristics of the honeycomb were studied by varying the separation between the honeycomb and the absorber plate. The optimal value of the separation was found to be 3.3 mm for which the heat transfer coefficient is 3.06 W m−2 K−1. This supports result of previous similar experiments. Further we test the honeycomb through a field experiment conducted in Delhi (28.6°N, 77°E and found that when the incident angle of the solar radiation is within 20° then the performance of the system with the honeycomb is better than the one without the honeycomb.

  20. Evacuation of mixed populations from trains on bridges

    DEFF Research Database (Denmark)

    Kindler, C.; Sørensen, J.G.; Dederichs, A.S.

    2012-01-01

    An understanding of human evacuation dynamics and performance are important when designing complex buildings such as bridges and when applying performance-based codes in order to reduce the risk of exposing occupants to critical conditions in case of fire. The majority of previous studies deal....... The discussion of "equal access" is only followed slowly by the demand on "equal egress". However, the passengers on trains on bridges are rarely homogeneous mixture. At the same time equal egress is far from assured today. In this paper the evacuation of mixed populations from trains on bridges are considered....... The populations applied in the experiment are mixed according to a composition corresponding to the population of Denmark. The study has the following findings: the total evacuation times increase with a factor 1.5 when accounting for a mixed population comprehending a variety of age and impairments. The seating...

  1. Simulation of the shopping center 'Zona I' evacuation

    Directory of Open Access Journals (Sweden)

    Jevtić Radoje B.

    2014-01-01

    Full Text Available One of the most important and the most complex tasks in human protection and human safety in objects is the projecting of the object evacuation. There are many factors that could effect on the opportune living of object such as object assignment, arrangement of rooms, arrangement of furniture, arrangement of exits, occupant speed and many other that human lives and material properties depend on. This is very important for objects with great number of humans, such as high residential objects, shopping centers, schools, hospitals etc. This paper has written to show the possible evacuation situations and calculate minimal time for evacuation in case of the shopping center 'Zona I' in Niš.

  2. Effectiveness and risks associated with sheltering and evacuation

    International Nuclear Information System (INIS)

    Mohseni, A.; McKenna, T.

    1995-01-01

    The United States Nuclear Regulatory Commission (NRC) and the Environmental Protection Agency (EPA) have assessed the risks and benefits associated with evacuation and sheltering following a severe reactor accident. In the case of a severe accident and the associated uncertainties with the source term and containment behaviour, these assessments suggest that prompt evacuation of areas close to the plant offers the highest protection of the public against acute doses. Sheltering may be used as an alternative in special circumstances where evacuation may not be feasible. The source term associated with reactor accidents and containment failure mechanism affect the effectiveness of different protective measures. A comparison of different protective measures is made and results discussed. (Author). 9 refs., 4 figs., 2 tabs

  3. CLEAR (Calculates Logical Evacuation And Response): A generic transportation network model for the calculation of evacuation time estimates

    International Nuclear Information System (INIS)

    Moeller, M.P.; Desrosiers, A.E.; Urbanik, T. II

    1982-03-01

    This paper describes the methodology and application of the computer model CLEAR (Calculates Logical Evacuation And Response) which estimates the time required for a specific population density and distribution to evacuate an area using a specific transportation network. The CLEAR model simulates vehicle departure and movement on a transportation network according to the conditions and consequences of traffic flow. These include handling vehicles at intersecting road segments, calculating the velocity of travel on a road segment as a function of its vehicle density, and accounting for the delay of vehicles in traffic queues. The program also models the distribution of times required by individuals to prepare for an evacuation. In order to test its accuracy, the CLEAR model was used to estimate evacuation times for the emergency planning zone surrounding the Beaver Valley Nuclear Power Plant. The Beaver Valley site was selected because evacuation time estimates had previously been prepared by the licensee, Duquesne Light, as well as by the Federal Emergency Management Agency and the Pennsylvania Emergency Management Agency. A lack of documentation prevented a detailed comparison of the estimates based on the CLEAR model and those obtained by Duquesne Light. However, the CLEAR model results compared favorably with the estimates prepared by the other two agencies. (author)

  4. SCALING AN URBAN EMERGENCY EVACUATION FRAMEWORK: CHALLENGES AND PRACTICES

    Energy Technology Data Exchange (ETDEWEB)

    Karthik, Rajasekar [ORNL; Lu, Wei [ORNL

    2014-01-01

    Critical infrastructure disruption, caused by severe weather events, natural disasters, terrorist attacks, etc., has significant impacts on urban transportation systems. We built a computational framework to simulate urban transportation systems under critical infrastructure disruption in order to aid real-time emergency evacuation. This framework will use large scale datasets to provide a scalable tool for emergency planning and management. Our framework, World-Wide Emergency Evacuation (WWEE), integrates population distribution and urban infrastructure networks to model travel demand in emergency situations at global level. Also, a computational model of agent-based traffic simulation is used to provide an optimal evacuation plan for traffic operation purpose [1]. In addition, our framework provides a web-based high resolution visualization tool for emergency evacuation modelers and practitioners. We have successfully tested our framework with scenarios in both United States (Alexandria, VA) and Europe (Berlin, Germany) [2]. However, there are still some major drawbacks for scaling this framework to handle big data workloads in real time. On our back-end, lack of proper infrastructure limits us in ability to process large amounts of data, run the simulation efficiently and quickly, and provide fast retrieval and serving of data. On the front-end, the visualization performance of microscopic evacuation results is still not efficient enough due to high volume data communication between server and client. We are addressing these drawbacks by using cloud computing and next-generation web technologies, namely Node.js, NoSQL, WebGL, Open Layers 3 and HTML5 technologies. We will describe briefly about each one and how we are using and leveraging these technologies to provide an efficient tool for emergency management organizations. Our early experimentation demonstrates that using above technologies is a promising approach to build a scalable and high performance urban

  5. Getting out of harm's way - evacuation from tsunamis

    Science.gov (United States)

    Jones, Jeanne M.; Wood, Nathan J.; Gordon, Leslie C.

    2015-01-01

    Scientists at the U.S. Geological Survey (USGS) have developed a new mapping tool, the Pedestrian Evacuation Analyst, for use by researchers and emergency managers to estimate how long it would take for someone to travel on foot out of a tsunami-hazard zone. The ArcGIS software extension, released in September 2014, allows the user to create maps showing travel times out of hazard zones and to determine the number of people that may or may not have enough time to evacuate. The maps take into account the elevation changes and the different types of land cover that a person would encounter along the way.

  6. Air solar collectors in building use - A review

    Science.gov (United States)

    Bejan, Andrei-Stelian; Labihi, Abdelouhab; Croitoru, Cristiana; Catalina, Tiberiu

    2018-02-01

    In the current energy and environmental context it is imperative to implement systems based on renewable energy sources in order to reduce energy consumptions worldwide. Solar collectors are studied by many years and many researchers are focusing their attention in order to increase their efficiency and cost-effectiveness. Water solar collectors are often implemented for domestic hot water, heating or industrial processes and already have a place on the market. A promising system which is not yet widely known is represented by air solar collectors that could represent an efficient way to use the solar energy with a lower investment cost, a system that can be used in order to preheat the fresh air required for heating, drying, or to maintain a minimum temperature during winter. This paper presents a comprehensive literature review on air solar collectors used mainly in buildings, acting as a solar wall. Air solar collectors are roughly classified into two types: glazed and opaque. The present study comprises the solar collector classification, applications and their main parameters with a special focus on opaque solar collectors.

  7. Evaluation of heat transfer enhancement in air-heating collectors

    Energy Technology Data Exchange (ETDEWEB)

    Mattox, D. L.

    1979-06-01

    The present research effort was initiated for the purpose of increasing the thermal efficiency of air heating solar collectors through identification and development of optimum design and operation criteria for solar absorber-to-air heat exchangers. Initially this effort took the form of a solar collector systems analysis to evaluate the impact of various techniques for enhancing the heat transfer between the absorber and air stream on overall thermal performance of the entire solar collector. This systems analysis resulted in the selection of solar collector designs providing ducted cooling air on the absorber shaded side as a base line. A transient heat transfer analysis of a complete solar air heating collector was used to demonstrate that an optimum absorber-to-air heat exchanger design could be provided with several interrupted fin configurations. Additional analyses were performed to establish that the maximum solar collector thermal performance to required pumping power was realized for a Reynolds number range of 1000 to 2000. This Reynolds number range was used to establish a theoretical design limit curve for maximum thermal performance versus required pumping power for all interrupted fin designs as published in the open literature. Heat and momentum transfer empirical relationships were defined for scaling the state-of-the-art high conductance fin designs identified from a compact configuration to the less compact designs needed for solar collectors.

  8. PERFORMANCE EVALUATION OF SOLAR COLLECTORS USING A SOLAR SIMULATOR

    Directory of Open Access Journals (Sweden)

    M. Norhafana

    2015-11-01

    Full Text Available Solar water heating systems is one of the applications of solar energy. One of the components of a solar water heating system is a solar collector that consists of an absorber. The performance of the solar water heating system depends on the absorber in the solar collector. In countries with unsuitable weather conditions, the indoor testing of solar collectors with the use of a solar simulator is preferred. Thus, this study is conducted to use a multilayered absorber in the solar collector of a solar water heating system as well as to evaluate the performance of the solar collector in terms of useful heat of the multilayered absorber using the multidirectional ability of a solar simulator at several values of solar radiation. It is operated at three variables of solar radiation of 400 W/m2, 550 W/m2 and 700 W/m2 and using three different positions of angles at 0º, 45º and 90º. The results show that the multilayer absorber in the solar collector is only able to best adapt at 45° of solar simulator with different values of radiation intensity. At this angle the maximum values of useful heat and temperature difference are achieved. KEYWORDS: solar water heating system; solar collector; multilayered absorber; solar simulator; solar radiation 

  9. Air solar collectors in building use - A review

    Directory of Open Access Journals (Sweden)

    Bejan Andrei-Stelian

    2018-01-01

    Full Text Available In the current energy and environmental context it is imperative to implement systems based on renewable energy sources in order to reduce energy consumptions worldwide. Solar collectors are studied by many years and many researchers are focusing their attention in order to increase their efficiency and cost-effectiveness. Water solar collectors are often implemented for domestic hot water, heating or industrial processes and already have a place on the market. A promising system which is not yet widely known is represented by air solar collectors that could represent an efficient way to use the solar energy with a lower investment cost, a system that can be used in order to preheat the fresh air required for heating, drying, or to maintain a minimum temperature during winter. This paper presents a comprehensive literature review on air solar collectors used mainly in buildings, acting as a solar wall. Air solar collectors are roughly classified into two types: glazed and opaque. The present study comprises the solar collector classification, applications and their main parameters with a special focus on opaque solar collectors.

  10. Intrarenal purinergic signaling in the control of renal tubular transport

    DEFF Research Database (Denmark)

    Prætorius, Helle; Leipziger, Jens Georg

    2010-01-01

    Renal tubular epithelial cells receive hormonal input that regulates volume and electrolyte homeostasis. In addition, numerous intrarenal, local signaling agonists have appeared on the stage of renal physiology. One such system is that of intrarenal purinergic signaling. This system involves all......-reaching advances indicate that ATP is often used as a local transmitter for classical sensory transduction. This transmission apparently also applies to sensory functions in the kidney. Locally released ATP is involved in sensing of renal tubular flow or in detecting the distal tubular load of NaCl at the macula...

  11. Perfis tubulares : aspectos arquitetônicos e estruturais.

    OpenAIRE

    Gerken, Fernanda de Sousa

    2003-01-01

    Programa de Pós Graduação em Engenharia Civil. Departamento de Engenharia Civil, Escola de Minas, Universidade Federal de Ouro Preto. O presente trabalho tem como objetivo apresentar uma visão geral da utilização das estruturas tubulares no contexto da evolução das estruturas metálicas em geral, com destaque para o estudo de obras que mostram o estado da arte da construção tubular no Brasil. A utilização dos perfis tubulares estruturais é abordada tanto do ponto de vista da ...

  12. Modelling effects of current distributions on performance of micro-tubular hollow fibre solid oxide fuel cells

    International Nuclear Information System (INIS)

    Doraswami, U.; Droushiotis, N.; Kelsall, G.H.

    2010-01-01

    A three-dimensional model, considering mass, momentum, energy and charge conservation, was developed and the equations solved to describe the physico-chemical phenomena occurring within a single, micro-tubular hollow fibre solid oxide fuel cell (HF-SOFC). The model was used to investigate the spatial distributions of potential, current and reactants in a 10 mm long HF-SOFC. The predicted effects of location of current collectors, electrode conductivities, cathode thickness and porosity were analysed to minimise the ranges of current density distributions and maximise performance by judicious design. To decrease the computational load, azimuthal symmetry was assumed to model 50 and 100 mm long reactors in 2-D. With connectors at the same end of the HF-SOFC operating at a cell voltage of 0.5 V and a mean 5 kA m -2 , axial potential drops of ca. 0.14 V in the cathode were predicted, comparable to the cathode activation overpotential. Those potential drops caused average current densities to decrease from ca. 6.5 to ca.1 kA m -2 as HF-SOFC length increased from 10 to 100 mm, at which much of the length was inactive. Peak power densities were predicted to vary from 3.8 to -2 , depending on the location of the current collectors; performance increased with increasing cathode thickness and decreasing porosity.

  13. Fuzzy Approximate Model for Distributed Thermal Solar Collectors Control

    KAUST Repository

    Elmetennani, Shahrazed

    2014-07-01

    This paper deals with the problem of controlling concentrated solar collectors where the objective consists of making the outlet temperature of the collector tracking a desired reference. The performance of the novel approximate model based on fuzzy theory, which has been introduced by the authors in [1], is evaluated comparing to other methods in the literature. The proposed approximation is a low order state representation derived from the physical distributed model. It reproduces the temperature transfer dynamics through the collectors accurately and allows the simplification of the control design. Simulation results show interesting performance of the proposed controller.

  14. FLOW DISTRIBUTION IN A SOLAR COLLECTOR PANEL WITH HORIZONTAL FINS

    DEFF Research Database (Denmark)

    Fan, Jianhua; Shah, Louise Jivan; Furbo, Simon

    2005-01-01

    The objective of this work is to theoretically and experimentally investigate the flow and temperature distribution in a solar collector panel with an absorber consisting of horizontal fins. Fluid flow and heat transfer in the collector panel are studied by means of computational fluid dynamics...... (CFD) calculations. Further, experimental investigations of a 12.5 m² solar collector panel with 16 parallel connected horizontal fins are carried out. The flow distribution through the absorber is evaluated by means of temperature measurements on the backside of the absorber tubes. The measured...

  15. Solar collector wall with active curtain system; Lasikatteinen massiivienen aurinkokeraeaejaeseinae

    Energy Technology Data Exchange (ETDEWEB)

    Ojanen, T.; Heimonen, I. [VTT Building Technology, Espoo (Finland). Building Physics, Building Services and Fire Technology

    1998-12-01

    Integration of solar collector into the building envelope structure brings many advantages. The disadvantage of a passive solar collector wall is that its thermal performance can not be controlled, which may cause temporary overheating and low thermal efficiency of the collector. The thermal performance of the collector wall can be improved by using controllable, active collector systems. In this paper a solar collector wall with a controllable curtain between the transparent and absorption layers is investigated. The curtain is made of several low-emissivity foil layers, which ensures low radiation heat transfer through the curtain. The curtain decreases the heat losses out from the collector wall and it improves the U-value of the wall. The curtain is used when the solar radiation intensity to the wall is not high enough or when the wall needs protection against overheating during warm weather conditions. The materials and building components used in the collector wall, except those of the curtain, are ordinary in buildings. The transparent layer can be made by using normal glazing technology and the thermal storage layer can be made out of brick or similar material. The solar energy gains through the glazing can be utilised better than in passive systems, because the curtain provides the wall with high thermal resistance outside the solar radiation periods. The thermal performance of the collector wall was studied experimentally using a Hot-Box apparatus equipped with a solar lamp. Numerical simulations were carried out to study the yearly performance of the collector wall under real climate conditions. The objectives were to determine the thermal performance of the collector wall and to study how to optimise the use of solar radiation in this system. When the curtain with high thermal resistance is used actively, the temperature level of the thermal storage layer in the wall is relatively high also during dark periods and the heat losses out from the storage

  16. Small-Sized Parabolic Trough Collector System for Solar Dehumidification Application: Design, Development, and Potential Assessment

    Directory of Open Access Journals (Sweden)

    Ghulam Qadar Chaudhary

    2018-01-01

    Full Text Available The current study presents a numerical and real-time performance analysis of a parabolic trough collector (PTC system designed for solar air-conditioning applications. Initially, a thermodynamic model of PTC is developed using engineering equation solver (EES having a capacity of around 3 kW. Then, an experimental PTC system setup is established with a concentration ratio of 9.93 using evacuated tube receivers. The experimental study is conducted under the climate of Taxila, Pakistan in accordance with ASHRAE 93-1986 standard. Furthermore, PTC system is integrated with a solid desiccant dehumidifier (SDD to study the effect of various operating parameters such as direct solar radiation and inlet fluid temperature and its impact on dehumidification share. The experimental maximum temperature gain is around 5.2°C, with the peak efficiency of 62% on a sunny day. Similarly, maximum thermal energy gain on sunny and cloudy days is 3.07 kW and 2.33 kW, respectively. Afterwards, same comprehensive EES model of PTC with some modifications is used for annual transient analysis in TRNSYS for five different climates of Pakistan. Quetta revealed peak solar insolation of 656 W/m2 and peak thermal energy 1139 MJ with 46% efficiency. The comparison shows good agreement between simulated and experimental results with root mean square error of around 9%.

  17. Low-cost small scale parabolic trough collector design for manufacturing and deployment in Africa

    Science.gov (United States)

    Orosz, Matthew; Mathaha, Paul; Tsiu, Anadola; Taele, B. M.; Mabea, Lengeta; Ntee, Marcel; Khakanyo, Makoanyane; Teker, Tamer; Stephens, Jordan; Mueller, Amy

    2016-05-01

    Concentrating Solar Power is expanding its deployment on the African subcontinent, highlighting the importance of efforts to indigenize manufacturing of this technology to increase local content and therefore local economic benefits of these projects. In this study a design for manufacturing (DFM) exercise was conducted to create a locally produced parabolic trough collector (the G4 PTC). All parts were sourced or fabricated at a production facility in Lesotho, and several examples of the design were prototyped and tested with collaborators in the Government of Lesotho's Appropriate Technology Services division and the National University of Lesotho. Optical and thermal performance was simulated and experimentally validated, and pedagogical pre-commercial versions of the PTC have been distributed to higher education partners in Lesotho and Europe. The cost to produce the PTC is 180 USD/m2 for a locally manufactured heat collection element (HCE) capable of sustaining 250C operation at ~65% efficiency. A version with an imported evacuated HCE can operate at 300°C with 70% efficiency. Economically relevant applications for this locally produced PTC include industrial process heat and distributed generation scenarios where cogeneration is required.

  18. 76 FR 43265 - Proposed Information Collection; Comment Request; Evacuation Movement and Behavior Questionnaire

    Science.gov (United States)

    2011-07-20

    ... DEPARTMENT OF COMMERCE National Institute of Standards and Technology Proposed Information Collection; Comment Request; Evacuation Movement and Behavior Questionnaire AGENCY: National Institute of... collecting data on evacuation behavior and movement of occupants from approximately 50 high-rise building...

  19. Development of a time-dependent hurricane evacuation model for the New Orleans area : [technical summary].

    Science.gov (United States)

    2013-01-01

    When hurricanes threaten coastal cities, the most eff ective strategy to mitigate mortality is to evacuate the population : at risk. However, public offi cials face several transportation challenges when managing evacuations from a large city : like ...

  20. Integrating supply and demand aspects of transportation for mass evacuation under disasters.

    Science.gov (United States)

    2009-10-15

    This study seeks to address real-time operational needs in the context of the evacuation response problem by providing a capability to dynamically route vehicles under evacuation, thereby being responsive to the actual conditions unfolding in real-ti...

  1. Craft-Joule Project: Stagnation proof transparently insulated flat plate solar collector (static)

    Energy Technology Data Exchange (ETDEWEB)

    Oliva, A; Cadafalch, J; Perez-Segarra, C.D. [Universitat Politecnica de Catalunya, Barcelona (Spain)] (and others)

    2000-07-01

    The STATIC (STAgnation proof Transparently Insulated flat plate Solar Collector) project is a Craft-Joule Project within the framework of the Non Nuclear Energy Programme Joule III coordinated by the Centre Technologic de Transferencia de Calor (CTTC). The core group of SMEs involved in the project has its main economical activity in the field of solar thermal systems at low temperature level (domestic hot water, solar heating, etc.). Beyond this, a large application potential exists for solar heating at medium temperature level (from 80 to 160 Celsius degrees) : industrial process heat, solar cooling and air conditioning, solar drying , distillation and desalination. Three of the four SME proposers are located in Southern Europe and in the Caribean, where a continuos increase of the demand for air conditioning and cooling has been demonstrated in the last years. The recent development of flat plate solar collectors with honeycomb-type transparent insulation cover has shown that this type of collectors can become a low cost alternative to evacuated tube and high concentrating CPC collectors in the medium temperature range from 80 to 160 Celsius degrees. With the expected reduction of collector cost, that forms 30%-50% of total system cost, a decisive break-through of solar thermal systems using heat in the medium temperature range can be achieved. The feasibility and good performance of these solar collectors has been proved in several prototypes. Nevertheless, up to now no commercial products are available. In order to reach this, the following developments of new concepts are necessary and are being carried out within this project: solution of the problem of overheating: development of collector versions for different working temperatures: optimization of the design with the support of high level numerical simulation. Several prototypes of the new solar collectors are being tested. System tests will also be carried or for two test arrays of optimized collector

  2. Optimal control of diarrhea transmission in a flood evacuation zone

    Science.gov (United States)

    Erwina, N.; Aldila, D.; Soewono, E.

    2014-03-01

    Evacuation of residents and diarrhea disease outbreak in evacuation zone have become serious problem that frequently happened during flood periods. Limited clean water supply and infrastructure in evacuation zone contribute to a critical spread of diarrhea. Transmission of diarrhea disease can be reduced by controlling clean water supply and treating diarrhea patients properly. These treatments require significant amount of budget, which may not be fulfilled in the fields. In his paper, transmission of diarrhea disease in evacuation zone using SIRS model is presented as control optimum problem with clean water supply and rate of treated patients as input controls. Existence and stability of equilibrium points and sensitivity analysis are investigated analytically for constant input controls. Optimum clean water supply and rate of treatment are found using optimum control technique. Optimal results for transmission of diarrhea and the corresponding controls during the period of observation are simulated numerically. The optimum result shows that transmission of diarrhea disease can be controlled with proper combination of water supply and rate of treatment within allowable budget.

  3. A novel grid-based mesoscopic model for evacuation dynamics

    Science.gov (United States)

    Shi, Meng; Lee, Eric Wai Ming; Ma, Yi

    2018-05-01

    This study presents a novel grid-based mesoscopic model for evacuation dynamics. In this model, the evacuation space is discretised into larger cells than those used in microscopic models. This approach directly computes the dynamic changes crowd densities in cells over the course of an evacuation. The density flow is driven by the density-speed correlation. The computation is faster than in traditional cellular automata evacuation models which determine density by computing the movements of each pedestrian. To demonstrate the feasibility of this model, we apply it to a series of practical scenarios and conduct a parameter sensitivity study of the effect of changes in time step δ. The simulation results show that within the valid range of δ, changing δ has only a minor impact on the simulation. The model also makes it possible to directly acquire key information such as bottleneck areas from a time-varied dynamic density map, even when a relatively large time step is adopted. We use the commercial software AnyLogic to evaluate the model. The result shows that the mesoscopic model is more efficient than the microscopic model and provides more in-situ details (e.g., pedestrian movement pattern) than the macroscopic models.

  4. Performance analysis of double basin solar still with evacuated tubes

    International Nuclear Information System (INIS)

    Hitesh N Panchal; Shah, P. K.

    2013-01-01

    Solar still is a very simple device, which is used for solar distillation process. In this research work, double basin solar still is made from locally available materials. Double basin solar still is made in such a way that, outer basin is exposed to sun and lower side of inner basin is directly connected with evacuated tubes to increase distillate output and reducing heat losses of a solar still. The overall size of the lower basin is about 1006 mm x 325 mm x 380 mm, the outer basin is about 1006 mm x 536 mm x 100 mm Black granite gravel is used to increase distillate output by reducing quantity of brackish or saline water in the both basins. Several experiments have conducted to determine the performance of a solar still in climate conditions of Mehsana (latitude of 23 degree 59' and longitude of 72 degree 38'), Gujarat, like a double basin solar still alone, double basin solar still with different size black granite gravel, double basin solar still with evacuated tubes and double basin solar still with evacuated tubes and different size black granite gravel. Experimental results show that, connecting evacuated tubes with the lower side of the inner basin increases daily distillate output of 56% and is increased by 60%, 63% and 67% with average 10 mm, 20 mm and 30 mm size black granite gravel. Economic analysis of present double basin solar still is 195 days. (authors)

  5. Nonlinear Effects in Examples of Crowd Evacuation Scenarios

    DEFF Research Database (Denmark)

    Starke, Jens; Berg Thomsen, Kristian; Sørensen, Asger

    2014-01-01

    Severe accidents with many fatalities have occurred when too many pedestrians had to maneuver in too tight surroundings, as during evacuations of mass events. This demonstrates the importance of a better general understanding of pedestrians and emergent complex behavior in crowds. To this end, we...

  6. Integrating Decentralized Indoor Evacuation with Information Depositories in the Field

    Directory of Open Access Journals (Sweden)

    Haifeng Zhao

    2017-07-01

    Full Text Available The lonelier evacuees find themselves, the riskier become their wayfinding decisions. This research supports single evacuees in a dynamically changing environment with risk-aware guidance. It deploys the concept of decentralized evacuation, where evacuees are guided by smartphones acquiring environmental knowledge and risk information via exploration and knowledge sharing by peer-to-peer communication. Peer-to-peer communication, however, relies on the chance that people come into communication range with each other. This chance can be low. To bridge between people being not at the same time at the same places, this paper suggests information depositories at strategic locations to improve information sharing. Information depositories collect the knowledge acquired by the smartphones of evacuees passing by, maintain this information, and convey it to other passing-by evacuees. Multi-agent simulation implementing these depositories in an indoor environment shows that integrating depositories improves evacuation performance: It enhances the risk awareness and consequently increases the chance that people survive and reduces their evacuation time. For evacuating dynamic events, deploying depositories at staircases has been shown more effective than deploying them in corridors.

  7. Virtual environment simulation as a tool to support evacuation planning

    International Nuclear Information System (INIS)

    Mol, Antonio C.; Grecco, Claudio H.S.; Santos, Isaac J.A.L.; Carvalho, Paulo V.R.; Jorge, Carlos A.F.; Sales, Douglas S.; Couto, Pedro M.; Botelho, Felipe M.; Bastos, Felipe R.

    2007-01-01

    This work is a preliminary study of the use of a free game-engine as a tool to build and to navigate in virtual environments, with a good degree of realism, for virtual simulations of evacuation from building and risk zones. To achieve this goal, some adjustments in the game engine have been implemented. A real building with four floors, consisting of some rooms with furniture and people, has been virtually implemented. Simulations of simple different evacuation scenarios have been performed, measuring the total time spent in each case. The measured times have been compared with their corresponding real evacuation times, measured in the real building. The first results have demonstrated that the virtual environment building with the free game engine is capable to reproduce the real situation with a satisfactory level. However, it is important to emphasize that such virtual simulations serve only as an aid in the planning of real evacuation simulations, and as such must never substitute the later. (author)

  8. Emergency evacuation : how better interior design can improve passenger flow

    NARCIS (Netherlands)

    Boer, L.C.; Skjong, R.

    2001-01-01

    The paper presents some conclusions from the EU basic research project "MEPdesign" relevant for design of ship interiors. The findings are discussed with regard to passenger flow as a function of design parameters. The paper explains that current evacuation analyses may be overly optimistic. The

  9. CT guided stereotactic evacuation of hypertensive and traumatic intracerebral hematomas

    International Nuclear Information System (INIS)

    Hondo, Hideki; Matsumoto, Keizo

    1983-01-01

    Recent advancement of CT system provides not only definite diagnosis and location of intracerebral hematoma but also coordinates of the center of the hematoma. Trials of stereotactic evacuation of the hematoma have been reported by some authors in the cases of subacute or chronic stages of hypertensive intracerebral hemorrhage. In this series, similar surgery has been performed in 33 cases of hypertensive intracerebral hematoma including 22 cases in acute stage, and 2 cases of traumatic hematoma. Clinical outcomes were investigated and the results were considered to be equivalent or rather better in the conventional microsurgery with evacuation of hematoma under direct vision. However, there still remained controversial problems in the cases of threatened herniation signs, because in these cases regular surgery with total evacuation of the hematoma at one time might have been preferable. The benefits of this CT guided stereotactic approach for the evacuation of the hematoma were thought to be as follow: 1) the procedure is simple and safe, 2) operation is readily performed under local anesthesia, and 3) the hematoma was drained out totally by means of urokinase activity. It is our impression that this surgery not only is indicated as emergency treatment for the patients of high-age or in high risk, but also can institute as a routine surgery for the intracerebral hematomas in patients showing no herniation sign. (J.P.N.)

  10. Quantitative Comparison Between Crowd Models for Evacuation Planning and Evaluation

    NARCIS (Netherlands)

    Viswanathan, V.; Lee, C.E.; Lees, M.H.; Cheong, S.A.; Sloot, P.M.A.

    2014-01-01

    Crowd simulation is rapidly becoming a standard tool for evacuation planning and evaluation. However, the many crowd models in the literature are structurally different, and few have been rigorously calibrated against real-world egress data, especially in emergency situations. In this paper we

  11. Conceptualizing intragroup and intergroup dynamics within a controlled crowd evacuation.

    Science.gov (United States)

    Elzie, Terra; Frydenlund, Erika; Collins, Andrew J; Robinson, R Michael

    2015-01-01

    Social dynamics play a critical role in successful pedestrian evacuations. Crowd modeling research has made progress in capturing the way individual and group dynamics affect evacuations; however, few studies have simultaneously examined how individuals and groups interact with one another during egress. To address this gap, the researchers present a conceptual agent-based model (ABM) designed to study the ways in which autonomous, heterogeneous, decision-making individuals negotiate intragroup and intergroup behavior while exiting a large venue. A key feature of this proposed model is the examination of the dynamics among and between various groupings, where heterogeneity at the individual level dynamically affects group behavior and subsequently group/group interactions. ABM provides a means of representing the important social factors that affect decision making among diverse social groups. Expanding on the 2013 work of Vizzari et al., the researchers focus specifically on social factors and decision making at the individual/group and group/group levels to more realistically portray dynamic crowd systems during a pedestrian evacuation. By developing a model with individual, intragroup, and intergroup interactions, the ABM provides a more representative approximation of real-world crowd egress. The simulation will enable more informed planning by disaster managers, emergency planners, and other decision makers. This pedestrian behavioral concept is one piece of a larger simulation model. Future research will build toward an integrated model capturing decision-making interactions between pedestrians and vehicles that affect evacuation outcomes.

  12. A heterogeneous lattice gas model for simulating pedestrian evacuation

    Science.gov (United States)

    Guo, Xiwei; Chen, Jianqiao; Zheng, Yaochen; Wei, Junhong

    2012-02-01

    Based on the cellular automata method (CA model) and the mobile lattice gas model (MLG model), we have developed a heterogeneous lattice gas model for simulating pedestrian evacuation processes in an emergency. A local population density concept is introduced first. The update rule in the new model depends on the local population density and the exit crowded degree factor. The drift D, which is one of the key parameters influencing the evacuation process, is allowed to change according to the local population density of the pedestrians. Interactions including attraction, repulsion, and friction between every two pedestrians and those between a pedestrian and the building wall are described by a nonlinear function of the corresponding distance, and the repulsion forces increase sharply as the distances get small. A critical force of injury is introduced into the model, and its effects on the evacuation process are investigated. The model proposed has heterogeneous features as compared to the MLG model or the basic CA model. Numerical examples show that the model proposed can capture the basic features of pedestrian evacuation, such as clogging and arching phenomena.

  13. 14 CFR Appendix J to Part 25 - Emergency Evacuation

    Science.gov (United States)

    2010-01-01

    ... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Pt. 25, App. J Appendix J to Part 25—Emergency Evacuation...-candles prior to the activation of the airplane emergency lighting system. The source(s) of the initial... airplane emergency lighting system. (b) The airplane must be in a normal attitude with landing gear...

  14. Scenario analysis of large scale algae production in tubular photobioreactors

    NARCIS (Netherlands)

    Slegers, P.M.; Beveren, van P.J.M.; Wijffels, R.H.; Straten, van G.; Boxtel, van A.J.B.

    2013-01-01

    Microalgae productivity in tubular photobioreactors depends on algae species, location, tube diameter, biomass concentration, distance between tubes and for vertically stacked systems, the number of horizontal tubes per stack. A simulation model for horizontal and vertically stacked horizontal

  15. Hot Firing of a Full Scale Copper Tubular Combustion Chamber

    National Research Council Canada - National Science Library

    Cooley, C

    2002-01-01

    This paper describes the chamber design and hot firing test results for a full-scale copper tubular combustion chamber that has future application in a high-thrust, upper-stage expander cycle engine...

  16. Genetics Home Reference: renal tubular acidosis with deafness

    Science.gov (United States)

    ... adults with renal tubular acidosis with deafness have short stature, and many develop kidney stones. The metabolic acidosis ... enlarged vestibular aqueduct, can be seen with medical imaging. The vestibular aqueduct is a bony canal that ...

  17. Tubular forms of papova viruses in human laryngeal papilloma.

    Science.gov (United States)

    Arnold, W

    1979-01-01

    In two cases of recurrent laryngeal papillomatosis tubular forms of papova viruses could be observed. The same material revealed the close relation between nuclear chromatine and the release of particles, as well as a capsomere like substructure of the virions.

  18. The Fourier transform of tubular densities

    KAUST Repository

    Prior, C B

    2012-05-18

    We consider the Fourier transform of tubular volume densities, with arbitrary axial geometry and (possibly) twisted internal structure. This density can be used to represent, among others, magnetic flux or the electron density of biopolymer molecules. We consider tubes of both finite radii and unrestricted radius. When there is overlap of the tube structure the net density is calculated using the super-position principle. The Fourier transform of this density is composed of two expressions, one for which the radius of the tube is less than the curvature of the axis and one for which the radius is greater (which must have density overlap). This expression can accommodate an asymmetric density distribution and a tube structure which has non-uniform twisting. In addition we give several simpler expressions for isotropic densities, densities of finite radius, densities which decay at a rate sufficient to minimize local overlap and finally individual surfaces of the tube manifold. These simplified cases can often be expressed as arclength integrals and can be evaluated using a system of first-order ODEs. © 2012 IOP Publishing Ltd.

  19. A tubular electrode for radiofrequency ablation therapy

    KAUST Repository

    Antunes, Carlos Lemos Lemos Lemos

    2012-07-06

    Purpose – Due to its good mechanical and biocompatibility characteristics, nitinol SEMS is a popular endoprothesis used for relieving stricture problems in hollow organs due to carcinomas. Besides its mechanical application, SEMS can be regarded as well as potential electrode for performing RF ablation therapy on the tumor. The purpose of this work is to perform numerical and experimental analyses in order to characterize the lesion volume induced in biological tissue using this kind of tubular electrode. Design/methodology/approach – Data concerning electrical conductivity and dimension of the damaged tissue after RF ablation procedure were obtained from ex vivo samples. Next, numerical models using 3D finite element method were obtained reassembling the conditions considered at experimentation setup and results were compared. Findings – Numerical and experimental results show that a regular volume of damaged tissue can be obtained considering this type of electrode. Also, results obtained from numerical simulation are close to those obtained by experimentation. Originality/value – SEMSs, commonly used as devices to minimize obstruction problems due to the growth of tumors, may still be considered as an active electrode for RF ablation procedures. A method considering this observation is presented in this paper. Also, numerical simulation can be regarded in this case as a tool for determining the lesion volume.

  20. The Fourier transform of tubular densities

    International Nuclear Information System (INIS)

    Prior, C B; Goriely, A

    2012-01-01

    We consider the Fourier transform of tubular volume densities, with arbitrary axial geometry and (possibly) twisted internal structure. This density can be used to represent, among others, magnetic flux or the electron density of biopolymer molecules. We consider tubes of both finite radii and unrestricted radius. When there is overlap of the tube structure the net density is calculated using the super-position principle. The Fourier transform of this density is composed of two expressions, one for which the radius of the tube is less than the curvature of the axis and one for which the radius is greater (which must have density overlap). This expression can accommodate an asymmetric density distribution and a tube structure which has non-uniform twisting. In addition we give several simpler expressions for isotropic densities, densities of finite radius, densities which decay at a rate sufficient to minimize local overlap and finally individual surfaces of the tube manifold. These simplified cases can often be expressed as arclength integrals and can be evaluated using a system of first-order ODEs. (paper)

  1. Inflatable Tubular Structures Rigidized with Foams

    Science.gov (United States)

    Tinker, Michael L.; Schnell, Andrew R.

    2010-01-01

    Inflatable tubular structures that have annular cross sections rigidized with foams, and the means of erecting such structures in the field, are undergoing development. Although the development effort has focused on lightweight structural booms to be transported in compact form and deployed in outer space, the principles of design and fabrication are also potentially applicable to terrestrial structures, including components of ultralightweight aircraft, lightweight storage buildings and shelters, lightweight insulation, and sales displays. The use of foams to deploy and harden inflatable structures was first proposed as early as the 1960s, and has been investigated in recent years by NASA, the U.S. Air Force Research Laboratory, industry, and academia. In cases of deployable booms, most of the investigation in recent years has focused on solid cross sections, because they can be constructed relatively easily. However, solid-section foam-filled booms can be much too heavy for some applications. In contrast, booms with annular cross sections according to the present innovation can be tailored to obtain desired combinations of stiffness and weight through choice of diameters, wall thicknesses, and foam densities. By far the most compelling advantage afforded by this innovation is the possibility of drastically reducing weights while retaining or increasing the stiffnesses, relative to comparable booms that have solid foamfilled cross sections. A typical boom according to this innovation includes inner and outer polyimide film sleeves to contain foam that is injected between them during deployment.

  2. Tubular Initial Conditions and Ridge Formation

    Directory of Open Access Journals (Sweden)

    M. S. Borysova

    2013-01-01

    Full Text Available The 2D azimuth and rapidity structure of the two-particle correlations in relativistic A+A collisions is altered significantly by the presence of sharp inhomogeneities in superdense matter formed in such processes. The causality constraints enforce one to associate the long-range longitudinal correlations observed in a narrow angular interval, the so-called (soft ridge, with peculiarities of the initial conditions of collision process. This study's objective is to analyze whether multiform initial tubular structures, undergoing the subsequent hydrodynamic evolution and gradual decoupling, can form the soft ridges. Motivated by the flux-tube scenarios, the initial energy density distribution contains the different numbers of high density tube-like boost-invariant inclusions that form a bumpy structure in the transverse plane. The influence of various structures of such initial conditions in the most central A+A events on the collective evolution of matter, resulting spectra, angular particle correlations and vn-coefficients is studied in the framework of the hydrokinetic model (HKM.

  3. Hereditary Hypokalemic salt-losing tubular disorders

    International Nuclear Information System (INIS)

    Peters, M.; Konard, M.; Seyberth, H.W.

    2003-01-01

    The inherited hypokalemic tubular disorders are frequently summarized under the heading Bartter Syndrome since they share several clinical and biochemical findings such as renal salt wasting, hypokalemic metabolic alkalosis, normal blood pressure despite hypereninemic hyperaldosteronism and hyperplasia of the juxtaglomerular apparatus. However, careful characterization of the clinical phenotype and correlation with the clinical phenotype and the correlation with the underlying molecular basis justifies the differentiation into at least four distinct disease entities: (i) the hyperprostaglandin E syndrome or antenatal variant of Bartter syndrome (HPS/aBS), which is caused by mutations in either the Na-K-2Cl cotransporter or the potassium channel of the medullary thick ascending limb of Henle's loop; (ii) the HPS/aBS with sensorineural deafness which results from inactivating mutation in the Barttin beta-subunit of the renal chloride channels; (iii) the classic Bartter syndrome caused by mutations in the chloride channel of the distal nephron; and (iv)Gitelman's variant of Bartter syndrome which is caused by mutations of the Na-Cl cotransporter of the distal convoluted tubule. This review will summarize the clinical characteristics of these diseases and progress recently made in the identification of the underlying molecular defects that will hopefully add to the current knowledge of the pathogenesis of these diseases. (author)

  4. Evacuation and Sheltering of Hospitals in Emergencies: A Review of International Experience

    OpenAIRE

    Bagaria, Jayshree; Heggie, Caroline; Abrahams, Jonathan; Murray, Virginia

    2017-01-01

    Abstract Objective: A scoping exercise to establish how common hospital evacuations are, identify hospital evacuation policies and review case studies to identify trig-gers, processes and challenges involved in the evacuation of hospitals globally. Design: A systematic search of PubMed and disaster agency online resources, search of grey literature and media reports. Results: This study showed that hospitals are vulnerable to both natural and man made disasters and that hospital evacuations d...

  5. Evacuation of Hospitals during Disaster, Establishment of a Field Hospital, and Communication

    OpenAIRE

    Tekin, Erdal; Bayramoglu, Atif; Uzkeser, Mustafa; Cakir, Zeynep

    2017-01-01

    The buildings, working personnel, and patients and their relatives may directly or indirectly be affected by the disasters. Here we will discuss evacuation, establishing a field hospital, communication, the role of the media in disasters, and defending against sabotage. The affected individuals should be evacuated and transferred to secure zones safely and rapidly. How the decision for evacuation should be made and how the evacuation triage should be performed are important issues. Field hosp...

  6. Modeling constrained sintering of bi-layered tubular structures

    DEFF Research Database (Denmark)

    Tadesse Molla, Tesfaye; Kothanda Ramachandran, Dhavanesan; Ni, De Wei

    2015-01-01

    Constrained sintering of tubular bi-layered structures is being used in the development of various technologies. Densification mismatch between the layers making the tubular bi-layer can generate stresses, which may create processing defects. An analytical model is presented to describe the densi...... and thermo-mechanical analysis. Results from the analytical model are found to agree well with finite element simulations as well as measurements from sintering experiment....

  7. Electrolyte composition of renal tubular cells in gentamicin nephrotoxicity

    International Nuclear Information System (INIS)

    Matsuda, O.; Beck, F.X.; Doerge, A.T.; Thurau, K.

    1988-01-01

    The effect of long-term gentamicin administration on sodium, potassium, chloride and phosphorus concentrations was studied in individual rat renal tubular cells using electron microprobe analysis. Histological damage was apparent only in proximal tubular cells. The extent of damage was only mild after 7 days of gentamicin administration (60 mg/kg body wt/day) but much more pronounced after 10 days. GFR showed a progressive decline during gentamicin treatment. In non-necrotic proximal tubular cells, sodium was increased from 14.6 +/- 0.3 (mean +/- SEM) in controls to 20.6 +/- 0.4 after 7 and 22.0 +/- 0.8 mmol/kg wet wt after 10 days of gentamicin administration. Chloride concentration was higher only after 10 days (20.6 +/- 0.6 vs. 17.3 +/- 0.2 mmol/kg wet wt). Both cell potassium and phosphorus concentrations were diminished by 6 and 15, and by 8 and 25 mmol/kg wet wt after 7 and 10 days of treatment, respectively. In contrast, no major alterations in distal tubular cell electrolyte concentrations could be observed after either 7 or 10 days of gentamicin administration. As in proximal tubular cells, distal tubular cell phosphorus concentrations were, however, lowered by gentamicin treatment. These results clearly indicate that gentamicin exerts its main effect on proximal tubular cells. Decreased potassium and increased sodium and chloride concentrations were observed in proximal tubular cells exhibiting only mild histological damage prior to the onset of advanced tissue injury. Necrotic cells, on the other hand, showed widely variable intracellular electrolyte concentration patterns

  8. Flat solar collector an approach to its evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Sonino, T [Israel Atomic Energy Commission, Yavne. Soreq Nuclear Research Center

    1977-01-01

    The flat solar collector is the most widely used device for the utilization of solar energy, but its energetic and economic values are still debated. A preliminary energy and economic analysis is presented. The energy analysis indicates that the energy needed to produce one solar collector is equivalent to the electricity consumed by an electric water heater in roughly three months. The economic analysis indicates that the pay-back time for a solar collector varies from 5.5 to 7.7 yr. according to the discount rate. The economic analysis from a national point of view indicates that the use of solar collectors for domestic purposes could only reduce electricity consumption in Israel by 10%.

  9. Performance of jet impingement in unglazed air collectors

    Energy Technology Data Exchange (ETDEWEB)

    Belusko, M.; Saman, W.; Bruno, F. [Institute for Sustainable Systems and Technologies, University of South Australia, Mawson Lakes Boulevard, Mawson Lakes, SA 5095 (Australia)

    2008-05-15

    Jet impingement is effective at improving the heat transfer between air and a heated surface. Studies have shown that jet impingement can marginally improve the thermal efficiency of a glazed collector. However, little attention has been placed on applying jet impingement to an unglazed solar air collector. This paper presents a theoretical and experimental investigation identifying the performance characteristics of jet impingement. Overall, jet impingement was able to improve the thermal efficiency of the collector by 21%. An increase in the pressure loss was also measured but found to be small. The flow distribution of jets along the collector was the most significant factor in determining the efficiency. Increasing the hole spacing was found to improve the efficiency. (author)

  10. Bilinear reduced order approximate model of parabolic distributed solar collectors

    KAUST Repository

    Elmetennani, Shahrazed; Laleg-Kirati, Taous-Meriem

    2015-01-01

    This paper proposes a novel, low dimensional and accurate approximate model for the distributed parabolic solar collector, by means of a modified gaussian interpolation along the spatial domain. The proposed reduced model, taking the form of a low

  11. Mathematical Modeling of Dual Intake Transparent Transpired Solar Collector

    Directory of Open Access Journals (Sweden)

    Thomas Semenou

    2015-01-01

    Full Text Available Nowadays, in several types of commercial or institutional buildings, a significant rise of transpired solar collectors used to preheat the fresh air of the building can be observed. Nevertheless, when the air mass flow rate is low, the collector efficiency collapses and a large amount of energy remains unused. This paper presents a simple yet effective mathematical model of a transparent transpired solar collector (TTC with dual intake in order to remove stagnation problems in the plenum and ensure a better thermal efficiency and more heat recovery. A thermal model and a pressure loss model were developed. Then, the combined model was validated with experimental data from the Solar Rating and Certification Corporation (SRCC. The results show that the collector efficiency can be up to 70% and even 80% regardless of operating conditions. The temperature gain is able to reach 20°K when the solar irradiation is high.

  12. [Naturalists, collectors and theoreticians of museology].

    Science.gov (United States)

    Arabas, Iwona

    2009-01-01

    The origins of the contemporary collectorship dates from times when the sameness of art and science was commonly accepted. In those days relics of the ancient past and natural individuals of newly discovered lands were presented at the same time. Cosmological character of the collections manifested the tenacity of recognition and representation of the surrounding reality. A great impact on completion of collections of curiosities in Europe had Netherlands, and in the basin of Baltic Sea a remarkable significance was gained by Hanseatic Gdańsk. Collections of Jakub Breyn, Jakub Klein and Gotfryd Reyger became famous then. In the same way were imported individuals for Anna Jabłonowska that composed one of the most interesting European collections. In course of time merging such a great multiplicity of collections was beyond collectors' power and museum pieces from collections of curiosities were parcelled out. It was a real beginning of specialistic museums. A role of museum for science results from its function of methodical organizing collections that can be used by research workers. However, although the aims of scientific and museum centres are different, they come together on the occasion of museum recognition works when museums' workers borrow essential knowledge and methods from resources of science, and scientists search for useful research materials in museum resources.

  13. Performance evaluation for solar collectors in Taiwan

    International Nuclear Information System (INIS)

    Chang, T.P.

    2009-01-01

    In this paper, the global irradiation observed in Taiwan from 1990 to 1999 was used to estimate the optimal tilt angle for solar collectors. The observed data are resolved into diffusion and beam components, and transformed into instantaneous time frames using mathematical models. The energy gain on installing a single-axis tracked panel as compared to a traditional fixed panel is originally analyzed theoretically. In addition to the observation data, both types of radiation will be taken into account for comparison, i.e. both extraterrestrial radiation and global radiation predicted using empirical models. The results show that the yearly optimal angles for six selected stations are about 0.95 and 0.88 times their latitudes for extraterrestrial and predicted radiation, respectively. All of the observed irradiations are less than the predicted values for all times and stations, consequently resulting in a flatter tilt angle, with a few exceptions in summer. Since Taipei has the lowest clearness index, its yearly optimal angle calculated from observed data shows the greatest discrepancy when compared to its latitude. By employing a tracked panel, the yearly gains calculated from the observed data lie between 14.3% and 25.3%, which is significantly less than those from the extraterrestrial and predicted radiations

  14. Luminal nucleotides are tonic inhibitors of renal tubular transport

    DEFF Research Database (Denmark)

    Leipziger, Jens Georg

    2011-01-01

    PURPOSE OF REVIEW: Extracellular ATP is an essential local signaling molecule in all organ systems. In the kidney, purinergic signaling is involved in an array of functions and this review highlights those of relevance for renal tubular transport. RECENT FINDINGS: Purinergic receptors are express...... discovered as an important signaling compartment in which local purinergic signaling determines an inhibitory tone for renal tubular transport. Blocking components of this system leads to tubular hyper-absorption, volume retention and elevated blood pressure.......PURPOSE OF REVIEW: Extracellular ATP is an essential local signaling molecule in all organ systems. In the kidney, purinergic signaling is involved in an array of functions and this review highlights those of relevance for renal tubular transport. RECENT FINDINGS: Purinergic receptors are expressed...... in all renal tubular segments and their stimulation generally leads to transport inhibition. Recent evidence has identified the tubular lumen as a restricted space for purinergic signaling. The concentrations of ATP in the luminal fluids are sufficiently high to inflict a tonic inhibition of renal...

  15. Variable population exposure and distributed travel speeds in least-cost tsunami evacuation modelling

    Science.gov (United States)

    Fraser, Stuart A.; Wood, Nathan J.; Johnston, David A.; Leonard, Graham S.; Greening, Paul D.; Rossetto, Tiziana

    2014-01-01

    Evacuation of the population from a tsunami hazard zone is vital to reduce life-loss due to inundation. Geospatial least-cost distance modelling provides one approach to assessing tsunami evacuation potential. Previous models have generally used two static exposure scenarios and fixed travel speeds to represent population movement. Some analyses have assumed immediate departure or a common evacuation departure time for all exposed population. Here, a method is proposed to incorporate time-variable exposure, distributed travel speeds, and uncertain evacuation departure time into an existing anisotropic least-cost path distance framework. The method is demonstrated for hypothetical local-source tsunami evacuation in Napier City, Hawke's Bay, New Zealand. There is significant diurnal variation in pedestrian evacuation potential at the suburb level, although the total number of people unable to evacuate is stable across all scenarios. Whilst some fixed travel speeds approximate a distributed speed approach, others may overestimate evacuation potential. The impact of evacuation departure time is a significant contributor to total evacuation time. This method improves least-cost modelling of evacuation dynamics for evacuation planning, casualty modelling, and development of emergency response training scenarios. However, it requires detailed exposure data, which may preclude its use in many situations.

  16. The effects of meal size, body size and temperature on gastric evacuation in pikeperch

    DEFF Research Database (Denmark)

    Koed, Anders

    2001-01-01

    Prey size had no effect on the gastric evacuation rate of pikeperch Stizostedion lucioperca. The gastric evacuation was adequately described applying an exponent of 0.5 in the power model. Applying length instead of weight of pikeperch in the gastric evacuation model resulted in a change of estim...

  17. Molecular design of flotation collectors: A recent progress.

    Science.gov (United States)

    Liu, Guangyi; Yang, Xianglin; Zhong, Hong

    2017-08-01

    The nature of froth flotation is to selectively hydrophobize valuable minerals by collector adsorption so that the hydrophobized mineral particles can attach air bubbles. In recent years, the increasing commercial production of refractory complex ores has been urgent to develop special collectors for enhancing flotation separation efficiency of valuable minerals from these ores. Molecular design methods offer an effective way for understanding the structure-property relationship of flotation collectors and developing new ones. The conditional stability constant (CSC), molecular mechanics (MM), quantitative structure-activity relationship (QSAR), and first-principle theory, especially density functional theory (DFT), have been adopted to build the criteria for designing flotation collectors. Azole-thiones, guanidines, acyl thioureas and thionocarbamates, amide-hydroxamates, and double minerophilic-group surfactants such as Gemini, dithiourea and dithionocarbamate molecules have been recently developed as high-performance collectors. To design hydrophobic groups, the hydrophilic-hydrophobic balance parameters have been extensively used as criteria. The replacement of aryl group with aliphatic group or CC single bond(s) with CC double bond(s), reduction of carbon numbers, introduction of oxygen atom(s) and addition of trisiloxane to the tail terminal have been proved to be useful approaches for adjusting the surface activity of collectors. The role of molecular design of collectors in practical flotation applications was also summarized. Based on the critical review, some comments and prospects for further research on molecular design of flotation collectors were also presented in the paper. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Means of increasing efficiency of CPC solar energy collector

    Science.gov (United States)

    Chao, B.T.; Rabl, A.

    1975-06-27

    A device is provided for improving the thermal efficiency of a cylindrical radiant energy collector. A channel is placed next to and in close proximity to the nonreflective side of an energy reflective wall of a cylindrical collector. A coolant is piped through the channel and removes a portion of the nonreflective energy incident on the wall which is absorbed by the wall. The energy transferred to the coolant may be utilized in a useful manner.

  19. Proceedings of the solar thermal concentrating collector technology symposium

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, B.P.; Kreith, F. (eds.)

    1978-08-01

    The purpose of the symposium was to review the current status of the concentrating collector technology, to disseminate the information gained from experience in operating solar systems, and to highlight the significant areas of technology development that must be vigorously pursued to foster early commercialization of concentrating solar collectors. Separate abstracts were prepared for thirteen invited papers and working group summaries. Two papers were previously abstracted for EDB.

  20. Comparison of thermal solar collector technologies and their applications

    OpenAIRE

    Alarcón Villamil, Alexander; Hortúa, Jairo Eduardo; López, Andrea

    2013-01-01

    This paper presents the operation of different thermal solar collector technologies and their main characteristics. It starts by providing a brief description of the importance of using solar collectors as an alternative to reduce the environmental impact caused by the production of non-renewable sources like coal and oil. Subsequently, it focuses on each solar concentrator technology and finishes with a theoretical analysis hub application in different industrial processes. En este artícu...

  1. Transient analysis of the double pass photovoltaic thermal solar collector

    International Nuclear Information System (INIS)

    Alfegi, Ebrahim M.; Sopian, Kamaruzzaman; Abakr, Yousif A.

    2006-01-01

    A mathematical model of a double pass photovoltaic thermal (PV/T) solar collector is reported in this work. It is composed of five couple unsteady nonlinear partial differential equations which are solved by using Gear implicit numerical scheme. That model was validated against experimental data and was found to accurately predict the temperature of the circulated air as well as the temperature distribution of every static elements in a two-pass PV/T solar collector.(Author)

  2. Interaction of regulation and innovation: Solar air heating collectors

    OpenAIRE

    Kramer, K.

    2012-01-01

    Solar Air Heating Collectors have still a very small share of 0.8% of the nominal installed capacity in the solar heating and cooling market (151.7 GWth) [1]. Although constituting a niche market, the potential of those kind of collectors to provide heat for industrial processes, processing food, room heating, air preheating, drying processes or air conditioning could be significant. However, the technical potentials of the various technological solutions are not easy to compare. Such a compa...

  3. Ground collectors for heat pumps; Grondcollectoren voor warmtepompen

    Energy Technology Data Exchange (ETDEWEB)

    Van Krevel, A. [Techneco, Leidschendam (Netherlands)

    1999-10-01

    The dimensioning and cost optimisation of a closed vertical ground collector system has been studied. The so-called Earth Energy Designer (EED) computer software, specially developed for the calculations involved in such systems, proved to be a particularly useful tool. The most significant findings from the first part of the study, 'Heat extraction from the ground', are presented and some common misconceptions about ground collector systems are clarified. 2 refs.

  4. Modeling hurricane evacuation traffic : testing the gravity and intervening opportunity models as models of destination choice in hurricane evacuation.

    Science.gov (United States)

    2006-09-01

    The test was conducted by estimating the models on a portion of evacuation data from South Carolina following Hurricane Floyd, and then observing how well the models reproduced destination choice at the county level on the remaining data. The tests s...

  5. CLEAR (Calculates Logical Evacuation And Response): A Generic Transportation Network Model for the Calculation of Evacuation Time Estimates

    Energy Technology Data Exchange (ETDEWEB)

    Moeller, M. P.; Urbanik, II, T.; Desrosiers, A. E.

    1982-03-01

    This paper describes the methodology and application of the computer model CLEAR (Calculates Logical Evacuation And Response) which estimates the time required for a specific population density and distribution to evacuate an area using a specific transportation network. The CLEAR model simulates vehicle departure and movement on a transportation network according to the conditions and consequences of traffic flow. These include handling vehicles at intersecting road segments, calculating the velocity of travel on a road segment as a function of its vehicle density, and accounting for the delay of vehicles in traffic queues. The program also models the distribution of times required by individuals to prepare for an evacuation. In order to test its accuracy, the CLEAR model was used to estimate evacuatlon tlmes for the emergency planning zone surrounding the Beaver Valley Nuclear Power Plant. The Beaver Valley site was selected because evacuation time estimates had previously been prepared by the licensee, Duquesne Light, as well as by the Federal Emergency Management Agency and the Pennsylvania Emergency Management Agency. A lack of documentation prevented a detailed comparison of the estimates based on the CLEAR model and those obtained by Duquesne Light. However, the CLEAR model results compared favorably with the estimates prepared by the other two agencies.

  6. An improved dynamic test method for solar collectors

    DEFF Research Database (Denmark)

    Kong, Weiqiang; Wang, Zhifeng; Fan, Jianhua

    2012-01-01

    A comprehensive improvement of the mathematical model for the so called transfer function method is presented in this study. This improved transfer function method can estimate the traditional solar collector parameters such as zero loss coefficient and heat loss coefficient. Two new collector...... parameters t and mfCf are obtained. t is a time scale parameter which can indicate the heat transfer ability of the solar collector. mfCf can be used to calculate the fluid volume content in the solar collector or to validate the regression process by comparing it to the physical fluid volume content...... for the second-order differential term with 6–9min as the best averaging time interval. The measured and predicted collector power output of the solar collector are compared during a test of 13days continuously both for the ITF method and the QDT method. The maximum and averaging error is 53.87W/m2 and 5.22W/m2...

  7. Dual curvature acoustically damped concentrating collector. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    Smith, G.A.; Rausch, R.A.

    1980-05-01

    A development program was conducted to investigate the design and performance parameters of a novel, dual curvature, concentrating solar collector. The reflector of the solar collector is achieved with a stretched-film reflective surface that approximates a hyperbolic paraboloid and is capable of line-focusing at concentration ratios ranging from 10 to 20X. A prototype collector was designed based on analytical and experimental component trade-off activities as well as economic analyses of solar thermal heating and cooling systems incorporating this type of collector. A prototype collector incorporating six 0.66 x 1.22 m (2 x 4 ft) was fabricated and subjected to a limited thermal efficiency test program. A peak efficiency of 36% at 121/sup 0/C (250/sup 0/F) was achieved based upon the gross aperture area. Commercialization activities were conducted, including estimated production costs of $134.44/m/sup 2/ ($12.49/ft/sup 2/) for the collector assembly (including a local suntracker and controls) and $24.33/m/sup 2/ ($2.26/ft/sup 2/) for the reflector subassembly.

  8. EFFICIENCY AND LIFETIME OF SOLAR COLLECTORS FOR SOLAR HEATING PLANTS

    DEFF Research Database (Denmark)

    The 12.5 m² flat plate solar collector HT, today marketed by Arcon Solvarme A/S, has been used in solar heating plants in Scandinavia since 1983. The collector is designed to operate in a temperature interval between 40°C and 90°C. The efficiency of the collector has been strongly improved since...... it was introduced on the market. The paper will present the increase of the efficiency of the collector due to technical improvements since 1983. Further, measurements from the spring of 2009 of the efficiency of two HT collectors, which have been in operation in the solar heating plant Ottrupgaard, Skørping......, Denmark since 1994 with a constant high flow rate and in the solar heating plant Marstal, Denmark since 1996 with a variable flow rate, will be presented. The efficiencies will be compared to the efficiencies of the collectors when they were first installed in the solar heating plants. The measurements...

  9. EFFICIENCY AND LIFETIME OF SOLAR COLLECTORS FOR SOLAR HEATING PLANTS

    DEFF Research Database (Denmark)

    Fan, Jianhua; Chen, Ziqian; Furbo, Simon

    2009-01-01

    The 12.5 m² flat plate solar collector HT, today marketed by Arcon Solvarme A/S, has been used in solar heating plants in Scandinavia since 1983. The collector is designed to operate in a temperature interval between 40°C and 90°C. The efficiency of the collector has been strongly improved since...... it was introduced on the market. The paper will present the increase of the efficiency of the collector due to technical improvements since 1983. Further, measurements from the spring of 2009 of the efficiency of two HT collectors, which have been in operation in the solar heating plant Ottrupgaard, Skørping......, Denmark since 1994 with a constant high flow rate and in the solar heating plant Marstal, Denmark since 1996 with a variable flow rate, will be presented. The efficiencies will be compared to the efficiencies of the collectors when they were first installed in the solar heating plants. The measurements...

  10. Energy Analysis of Solar Collector With perforated Absorber Plate

    Directory of Open Access Journals (Sweden)

    Ammar A. Farhan

    2017-09-01

    Full Text Available The thermal performance of three solar collectors with 3, 6 mm and without perforation absorber plate was assessed experimentally. The experimental tests were implemented in Baghdad during the January and February 2017. Five values of airflow rates range between 0.01 – 0.1 m3/s were used through the test with a constant airflow rate during the test day. The variation of the following parameters air temperature difference, useful energy, absorber plate temperature, and collector efficiency was recorded every 15 minutes. The experimental data reports that the increases the number of absorber plate perforations with a small diameter is more efficient rather than increasing the hole diameter of the absorber plate with decreasing the perforation numbers. Maximum air temperature difference throughout the solar collector with 3, 6 mm perforations and without perforations are 17, 15, and 12 oC, respectively. Also, it can be concluded that the energy gained from the solar collector with 3 mm perforation absorber plate is 28.2 % more than the energy gained from solar collector without holes per day for 0.1 m3/s airflow rate. The maximum values of the thermal performance curves are 0.67, 0.64, and 0.56 for the solar collector with 3, 6 mm, and without perforations, respectively.

  11. Standarized performance tests of collectors of solar thermal energy: A steel flat-plate collector with two transparent covers and a proprietary coating

    Science.gov (United States)

    1976-01-01

    Basic test results of a flat-plate solar collector whose performance was determined in the NASA-Lewis solar simulator are given. The collector was tested over ranges of inlet temperature and flux level.

  12. Coloured solar collectors. Phase II : from laboratory samples to collector prototypes. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Schueler, A; Roecker, Ch; Chambrier, E de; Munari Probst, M

    2007-07-01

    This illustrated final report for the Swiss Federal Office of Energy (SFOE) deals with the second phase of a project concerning the architectural integration of glazed solar collectors into the facades of buildings for heat production. The factors that limit the integration of photovoltaic panels in facades are discussed. The authors state that, for a convincing demonstration, sufficiently large samples and high quality levels are needed. The sol-gel deposition of the multi-layered coatings on A4-sized glass panes demonstrated in the laboratory by EPFL-LESO are discussed. The coatings produced exhibit a coloured reflection in combination with a high solar transmittance, a homogenous appearance, and are free of visible defects. Film hardening by UV exposure is discussed: This should result in the speeding up of the sol-gel process and thus save energy, thereby significantly reducing costs. Collaboration with industry is discussed in which full-scale glass panes are to be coated with novel multiple layers. The novel glazing is to be integrated into first prototype collectors. The manufacturing and test processes for the prototypes manufactured are discussed in detail.

  13. Analysis of collector-emitter offset voltage of InGaP/GaAs composite collector double heterojunction bipolar transistor

    Science.gov (United States)

    Lew, K. L.; Yoon, S. F.

    2002-04-01

    The Ebers-Moll-like terminal current expressions of a composite collector double heterojunction bipolar transistor (DHBT), which takes the recombination effect into account, have been formulated and an expression for collector-emitter offset voltage [VCE(offset)] has been derived. Factors affecting the VCE(offset) of a composite collector DHBT are investigated and good agreement between the calculated and reported experimental results is shown. Analytical results showed that the transmission coefficient of the base-collector (B-C) junction does not have a considerable effect on the VCE(offset), provided that the B-C junction is of good quality. Thus, despite its asymmetric structure, the VCE(offset) of an optimally designed composite collector DHBT could be as low as that of a conventional DHBT. Hence a composite collector DHBT with low saturation voltage and negligible VCE(offset) is possible if the two conditions: (i) good quality B-C junction, (ii) base transport factor, α≈1, are fulfilled.

  14. Advanced Hybrid Particulate Collector Project Management Plan

    Energy Technology Data Exchange (ETDEWEB)

    Miller, S.J.

    1995-11-01

    As the consumption of energy increases, its impact on ambient air quality has become a significant concern. Recent studies indicate that fine particles from coal combustion cause health problems as well as atmospheric visibility impairment. These problems are further compounded by the concentration of hazardous trace elements such as mercury, cadmium, selenium, and arsenic in fine particles. Therefore, a current need exists to develop superior, but economical, methods to control emissions of fine particles. Since most of the toxic metals present in coal will be in particulate form, a high level of fine- particle collection appears to be the best method of overall air toxics control. However, over 50% of mercury and a portion of selenium emissions are in vapor form and cannot be collected in particulate control devices. Therefore, this project will focus on developing technology not only to provide ultrahigh collection efficiency of particulate air toxic emissions, but also to capture vapor- phase trace metals such as mercury and selenium. Currently, the primary state-of-the-art technologies for particulate control are fabric filters (baghouses) and electrostatic precipitators (ESPs). However, they both have limitations that prevent them from achieving ultrahigh collection of fine particulate matter and vapor-phase trace metals. The objective of this project is to develop a highly reliable advanced hybrid particulate collector (AHPC) that can provide > 99.99 % particulate collection efficiency for all particle sizes between 0.01 and 50 14m, is applicable for use with all U.S. coals, and is cost-0443competitive with existing technologies. Phase I of the project is organized into three tasks: Task I - Project Management, Reporting, and Subcontract Consulting Task 2 - Modeling, Design, and Construction of 200-acfm AHPC Model Task 3 - Experimental Testing and Subcontract Consulting

  15. Solar energy collector/storage system

    Energy Technology Data Exchange (ETDEWEB)

    Bettis, J.R.; Clearman, F.R.

    1983-05-24

    A solar energy collector/storage system which includes an insulated container having working fluid inlets and outlets and an opening, a light-transmitting member positioned over the opening, and a heat-absorbing member which is centrally situated, is supported in the container, and is made of a mixture of gypsum , lampblack, and water. A light-reflecting liner made of corrugated metal foil preferably is attached to the internal surface of the container. The opening of the container is positioned in optical alignment with a source of solar energy. A light-reflecting cover optionally can be hingedly attached to the container, and can be positioned such as to reflect solar energy rays into the container. The system is adaptable for use with a working gas (e.g., air) and/or a working liquid (e.g., water) in separated flows which absorb heat from the heat-absorbing member, and which are useable per se or in an associated storage and/or circulatory system that is not part of this invention. The heatabsorbing mixture can also contain glass fibers. The heatabsorbing member is of such great load-bearing strength that it can also be used simultaneously as a structural member, e.g., a wall or ceiling of a room; and, thereby, the system can be used to heat a room, if a window of the room is the light-transmitting member and is facing the sun, and if the heat-absorbing member is a wall and/or the ceiling of the room and receives solar energy through the window.

  16. CISBAT 2007 - Solar collectors (heat and electricity)

    International Nuclear Information System (INIS)

    2007-01-01

    This is the third part of the proceedings of the 2007 CISBAT conference on Renewables in a changing climate, held in Lausanne, Switzerland. On the subject of Building and urban integration of renewables the following oral contributions are summarised: 'Facade integration of solar thermal collectors: present and future', 'Long term experiences with a versatile PV in roof system', 'Development of a design and performance prediction tool for the ground source heat pump and underground thermal storage system', 'Hygrothermal performance of earth-to-air heat exchanger: long-term data evaluation and short-term simulation' as well as 'The real cost of heating your home: a comparative assessment of home energy systems with external costs'. Poster-sessions on the subject include 'Central solar heating plants with seasonal heat storage', 'Analysis of forced convection for evaporative air flow and heat transfer in PV cooling channels', 'Renewable energy technology in Mali: constraints and options for a sustainable development', 'Effect of duct width in ducted photovoltaic facades', 'Design and actual measurement of a ground source heat pump system using steel foundation piles as ground heat exchangers', 'Development of an integrated water-water heat pump unit for low energy house and its application', 'PV effect in multilayer cells and blending of fullerene/poly (3-hexylthiophene) and phthalocyanine having NIR charge transfer absorption band', 'CdTe photovoltaic systems - an alternative energetic', 'Integration of renewable energy sources in a town, examples in Grenoble', 'A prospective analysis method for the conception of solar integration solutions in buildings' and 'Energy and aesthetic improvements for building integration of cost effective solar energy systems'. Further groups of presentations at the conference are reported on in separate database records. An index of authors completes the proceedings

  17. Sampling efficiency of the Moore egg collector

    Science.gov (United States)

    Worthington, Thomas A.; Brewer, Shannon K.; Grabowski, Timothy B.; Mueller, Julia

    2013-01-01

    Quantitative studies focusing on the collection of semibuoyant fish eggs, which are associated with a pelagic broadcast-spawning reproductive strategy, are often conducted to evaluate reproductive success. Many of the fishes in this reproductive guild have suffered significant reductions in range and abundance. However, the efficiency of the sampling gear used to evaluate reproduction is often unknown and renders interpretation of the data from these studies difficult. Our objective was to assess the efficiency of a modified Moore egg collector (MEC) using field and laboratory trials. Gear efficiency was assessed by releasing a known quantity of gellan beads with a specific gravity similar to that of eggs from representatives of this reproductive guild (e.g., the Arkansas River Shiner Notropis girardi) into an outdoor flume and recording recaptures. We also used field trials to determine how discharge and release location influenced gear efficiency given current methodological approaches. The flume trials indicated that gear efficiency ranged between 0.0% and 9.5% (n = 57) in a simple 1.83-m-wide channel and was positively related to discharge. Efficiency in the field trials was lower, ranging between 0.0% and 3.6%, and was negatively related to bead release distance from the MEC and discharge. The flume trials indicated that the gellan beads were not distributed uniformly across the channel, although aggregation was reduced at higher discharges. This clustering of passively drifting particles should be considered when selecting placement sites for an MEC; further, the use of multiple devices may be warranted in channels with multiple areas of concentrated flow.

  18. Effect of openings collectors and solar irradiance on the thermal efficiency of flat plate-finned collector for indirect-type passive solar dryer

    Science.gov (United States)

    Batubara, Fatimah; Dina, Sari Farah; Klaudia Kathryn Y., M.; Turmuzi, M.; Siregar, Fitri; Panjaitan, Nora

    2017-06-01

    Research on the effect of openings solar collector and solar irradiance to thermal efficiency has been done. Solar collector by flat plate-finned type consists of 3 ply insulator namely wood, Styrofoam and Rockwool with thickness respectively are 10 mm, 25 mm and 50 mm. Absorber plate made of aluminum sheet with thickness of 0.30 mm, painted by black-doff. Installation of 19 units fins (length x height x thickness: 1000x20x10 mm) on the collector will increase surface area of absorber so it can receive much more solar energy. The solar collector cover is made of glass (thickness of 5 mm). During the research, the solar irradiance and temperature of collector are measured and recorded every five minutes. Temperature measurement performed on the surface of the absorber plate, inside of collector, surface cover and the outer side insulator (plywood). This data is used to calculate the heat loss due to conduction, convection and radiation on the collector. Openings of collectors vary as follows: 100%, 75%, 15% and 0% (total enclosed). The data collecting was conducted from 09.00 am to 17.00 pm and triplicates. The collector thermal efficiency calculated based on the ratio of the amount of heat received to the solar irradiance absorbed. The results show that each of openings solar collector has different solar irradiance (because it was done on a different day) which is in units of W/m2: 390 (100% open), 376 (75% open), 429 (15% open), and 359 (totally enclosed). The highest thermal efficiency is in openings variation of 15% opened. These results indicate that the efficiency of the collector is influenced by the solar irradiance received by the collector and the temperature on the collector plate. The highest thermal efficiency is in variation of openings 15%. These indicate that the efficiency of the collector was influenced by solar irradiance received by the collector and openings of the collector plate.

  19. Prey exoskeletons influence the course of gastric evacuation in Atlantic cod Gadus morhua

    DEFF Research Database (Denmark)

    Couturier, C. S.; Andersen, N. G.; Audet, C.

    2013-01-01

    species, Pandalus borealis, Pandalus montagui and Eualus macilentus, and the crab Chionoecetes opilio, were evacuated from the stomach at different rates. The duration of all stages increased with increasing ash (and carbonate) content of the fresh prey. Thickness, chemical composition and morphology...... of the prey exoskeleton all affected gastric evacuation: duration of initial delay, overall evacuation rate and a decreased evacuation rate at the end of the process. The power exponential function (PEF), with its shape parameter, described the course of evacuation for these prey types well, especially...

  20. Standardized performance tests of collectors of solar thermal energy-a flat-plate collector with a single-tube serpentine flow distribution

    Science.gov (United States)

    Johnson, S.

    1976-01-01

    This preliminary data report gives basic test results of a flat-plate solar collector whose performance was determined in the NASA-Lewis solar simulator. The collector was tested over ranges of inlet temperatures, fluxes and coolant flow rates. Collector efficienty is correlated in terms of inlet temperature and flux level.

  1. A study on evacuation time from lecture halls in Faculty of Engineering, Universiti Putra Malaysia

    Science.gov (United States)

    Othman, W. N. A. W.; Tohir, M. Z. M.

    2018-04-01

    An evacuation situation in any building involves many risks. The geometry of building and high potential of occupant load may affect the efficiency of evacuation process. Although fire safety rules and regulations exist, they remain insufficient to guarantee the safety of all building occupants and do not prevent the dramatic events to be repeated. The main objective of this project is to investigate the relationship between the movement time, travel speed and occupant density during a series of evacuation drills specifically for lecture halls. Generally, this study emphasizes on the movement of crowd within a limited space and includes the aspects of human behaviour. A series of trial evacuations were conducted in selected lecture halls at Faculty of Engineering, Universiti Putra Malaysia with the aim of collecting actual data for numerical analysis. The numerical data obtained during trial evacuations were used to determine the evacuation time, crowd movement and behaviour during evacuation process particularly for lecture halls. The evacuation time and number of occupants exiting from each exit were recorded. Video camera was used to record and observe the movement behaviour of occupants during evacuations. EvacuatioNZ was used to simulate the trials evacuations of DK 5 and the results predicted were compared with experimental data. EvacuatioNZ was also used to predict the evacuation time and the flow of occupants exiting from each door for DK 4 and DK 8.

  2. Year-round performance assessment of a solar parabolic trough collector under climatic condition of Bhiwani, India: A case study

    International Nuclear Information System (INIS)

    Kumar, Devander; Kumar, Sudhir

    2015-01-01

    Highlights: • Year-round performance of SPTC under the various climatic conditions is presented. • A detailed thermo-optical model for PTC system is developed. • A comparison of developed thermal model is done with experimental data of SNL. • Developed model is very helpful and effective tool in analyzing the PTC system. • Enlightens the importance of mini-level SPTC as a promising system to fulfill the energy demands. - Abstract: Solar parabolic trough collector (SPTC) is a well-known solar thermal system applied for solar electric generation. Nowadays, major attention is directed toward improving the performance of solar thermal systems with optimization of solar field production. In this research work, a comprehensive thermo-optical modeling has been proposed to evaluate the performance of a mini-level SPTC considering various heat equilibriums with the environment. Here, receiver wall temperature is considered as the base for modeling. Collector consists of a non-evacuated receiver tube with black paint coating and enveloped with glass cover. Available meteorological data in terms of global and diffuse solar insolations, air temperatures and wind speeds have been used as inputs for performance evaluation of SPTC with horizontal and inclined aperture planes. The validation of the proposed analytical model is justified with existing experimental results and yielded a close agreement. The developed model is successfully applied to a SPTC in order to estimate the through-out year performance characteristics in terms of water temperature rise, heat energy generation, optical and thermal efficiency for the climactic conditions of Bhiwani. The results enlighten that using 0.010 kg/s mass flow rate of water and aperture area of around 1.34 m"2, collector achieved maximum rise in water temperature 11.1 °C and 12.2 °C on horizontal and inclined planes, respectively in the month of April. The uppermost heat energy generation is found to be 2.38 kW h/day in May

  3. Optimization-based decision support to assist in logistics planning for hospital evacuations.

    Science.gov (United States)

    Glick, Roger; Bish, Douglas R; Agca, Esra

    2013-01-01

    The evacuation of the hospital is a very complex process and evacuation planning is an important part of a hospital's emergency management plan. There are numerous factors that affect the evacuation plan including the nature of threat, availability of resources and staff the characteristics of the evacuee population, and risk to patients and staff. The safety and health of patients is of fundamental importance, but safely moving patients to alternative care facilities while under threat is a very challenging task. This article describes the logistical issues and complexities involved in planning and execution of hospital evacuations. Furthermore, this article provides examples of how optimization-based decision support tools can help evacuation planners to better plan for complex evacuations by providing real-world solutions to various evacuation scenarios.

  4. Reflection on Lessons Learned: An Analysis of the Adverse Outcomes Observed During the Hurricane Rita Evacuation.

    Science.gov (United States)

    Baker, Karen

    2018-02-01

    In September 2005, nearly 3.7 million people evacuated the Texas coastline in advance of Hurricane Rita's landfall, making the event the largest emergency evacuation in US history. The Rita evacuation underscored the importance of planning for domestic mass-evacuation events, as the evacuation itself led to over 100 of the at least 119 deaths attributed to the storm. In the days preceding Rita's landfall, several cascading, interrelated circumstances precipitated such adverse outcomes. This article explores the series of events leading up to the evacuation's poor outcomes, the response following Rita to amend evacuation plans, and how Texas successfully implemented these changes during later storms to achieve better outcomes. (Disaster Med Public Health Preparedness. 2018;12:115-120).

  5. Performance analysis of a solar still coupled with evacuated heat pipes

    Science.gov (United States)

    Pramod, B. V. N.; Prudhvi Raj, J.; Krishnan, S. S. Hari; Kotebavi, Vinod

    2018-02-01

    In developing countries the need for better quality drinking water is increasing steadily. We can overcome this need by using solar energy for desalination purpose. This process includes fabrication and analysis of a pyramid type solar still coupled with evacuated heat pipes. This experiment using evacuated heat pipes are carried in mainly three modes namely 1) Still alone 2) Using heat pipe with evacuated tubes 3)Using evacuated heat pipe. For this work single basin pyramid type solar still with 1m2 basin area is fabricated. Black stones and Black paint are utilised in solar still to increase evaporation rate of water in basin. The heat pipe’s evaporator section is placed inside evacuated tube and the heat pipe’s condenser section is connected directly to the pyramid type solar still’s lower portion. The output of distillate water from still with evacuated heat pipe is found to be 40% more than the still using only evacuated tubes.

  6. Performance of cylindrical plastic solar collectors for air heating

    International Nuclear Information System (INIS)

    Abdullah, A.S.; Bassiouny, M.K.

    2014-01-01

    Highlights: • The study including the combined convective and radiative heat transfer analysis. • The solar collector is manufactured from LDPE films acting as a black absorber. • Comparisons between the experimental data and the theoretical methods have been made. • The thermal efficiency increases with decreasing the major axes of elliptic shape. • The Nusselt number between the absorber and the heated air is determined. - Abstract: A theoretical and experimental study including the combined convective and radiative heat transfer analysis of a flexible cylindrical type solar air-heater for agriculture crops dehydration as well as heating processes is presented. The solar collector is manufactured from LDPE films acting as a black absorber with a back insulation and double transparent covers sealed together along its edges. The collector is to be blown with a flow of pressurized air. The experiments are carried out with solar collectors of circular shapes having 0.5 m diameter and solar collectors of elliptic shapes having 0.55 m and 0.65 m major axis. Energy balance of the cover, absorber and air yield three simultaneous quadratic algebraic equations in the three unknowns namely, cover, absorber and outlet air temperatures. A computer program is written for calculating the outlet temperature using the Newton–Raphson method and the collector thermal efficiency in terms of its diameter, length, mass flow rate, inlet temperature and solar insolation. Moreover the Nusselt number between the absorber and the heated air is determined experimentally in relation with the Reynolds number. Comparisons between the experimental data and the theoretical methods for the collector efficiency demonstrate a good agreement. In addition of this, the present experimental results of Nusselt number are correlated and compared with a correlation of another authors

  7. Should evacuation standards be reviewed after a nuclear accident?

    International Nuclear Information System (INIS)

    Nifenecker, Herve

    2011-10-01

    The author comments the current practices of post-accident management of nuclear disasters. He outlines the peculiarities of nuclear evacuations with respect to other disasters. After referring to the use of life expectancy or of the reduction of life expectancy, for example for smokers, he suggests that irradiation could be expressed this way and then provide some intuitive information. He discusses the notion of linear no-threshold relationship which has been introduced by the ICRP after analysis of cancers noticed on survivors of Hiroshima and Nagasaki. He addresses the case of Fukushima, the issue of low doses applied to large populations. He discusses the limitations of the linear no-threshold relationship. He discusses possible improvements of evacuation procedures

  8. Conceptual study on the containment design aiming at 'no evacuation'

    International Nuclear Information System (INIS)

    Andou, Kouji; Takii, Taichi; Kikuyama, Tomohiko; Taminami, Tatsuya

    2003-01-01

    The next generation reactors represented in ABWR-II should enhance not only economics but also safety. Especially, the ideal target of 'No Evacuation', that is, no FP (Fission Product) release in severe accidents should be required. This paper provides the conceptual design achieving 'No Evacuation' by using only the passive systems, that are, the passive containment cooling system (PCCS), the large amount of water inside containment, outside pool by utilizing gap between containment and surrounding building, and the natural heat removal from the containment surface to atmosphere. Furthermore, it is also easy to adopt the countermeasure for airplane crash by using a dome shelter and the dispersed layout as an option. At the same time, the amount of the construction material of this concept is competitive comparing with that of the conventional BWR because it is easy to use the steel structure or the steel plate reinforced concrete structure over a wide area. (author)

  9. Theoretical predictions for glass flow into an evacuated canister

    International Nuclear Information System (INIS)

    Routt, K.R.; Crow, K.R.

    1983-01-01

    Radioactive waste currently stored at the Savannah River Plant in liquid form is to be immobilized by incorporating it into a borosilicate glass. The glass melter for this process will consist of a refractory lined, steel vessel operated at a glass temperature of 1150 0 C. At the end of a two-year projected melter lifetime, the glass inside the melter is to be drained prior to disposition of the melter vessel. One proposed technique for accomplishing this drainage is by sucking the glass into an evacuated canister. The theoretical bases for design of an evacuated canister for draining a glass melter have been developed and tested. The theoretical equations governing transient and steady-state flow were substantiated with both a silicone glass simulant and molten glass

  10. Community disruptions and business costs for distant tsunami evacuations using maximum versus scenario-based zones

    Science.gov (United States)

    Wood, Nathan J.; Wilson, Rick I.; Ratliff, Jamie L.; Peters, Jeff; MacMullan, Ed; Krebs, Tessa; Shoaf, Kimberley; Miller, Kevin

    2017-01-01

    Well-executed evacuations are key to minimizing loss of life from tsunamis, yet they also disrupt communities and business productivity in the process. Most coastal communities implement evacuations based on a previously delineated maximum-inundation zone that integrates zones from multiple tsunami sources. To support consistent evacuation planning that protects lives but attempts to minimize community disruptions, we explore the implications of scenario-based evacuation procedures and use the California (USA) coastline as our case study. We focus on the land in coastal communities that is in maximum-evacuation zones, but is not expected to be flooded by a tsunami generated by a Chilean earthquake scenario. Results suggest that a scenario-based evacuation could greatly reduce the number of residents and employees that would be advised to evacuate for 24–36 h (178,646 and 159,271 fewer individuals, respectively) and these reductions are concentrated primarily in three counties for this scenario. Private evacuation spending is estimated to be greater than public expenditures for operating shelters in the area of potential over-evacuations ($13 million compared to $1 million for a 1.5-day evacuation). Short-term disruption costs for businesses in the area of potential over-evacuation are approximately $122 million for a 1.5-day evacuation, with one-third of this cost associated with manufacturing, suggesting that some disruption costs may be recouped over time with increased short-term production. There are many businesses and organizations in this area that contain individuals with limited mobility or access and functional needs that may have substantial evacuation challenges. This study demonstrates and discusses the difficulties of tsunami-evacuation decision-making for relatively small to moderate events faced by emergency managers, not only in California but in coastal communities throughout the world.

  11. A spatiotemporal optimization model for the evacuation of the population exposed to flood hazard

    Science.gov (United States)

    Alaeddine, H.; Serrhini, K.; Maizia, M.

    2015-03-01

    Managing the crisis caused by natural disasters, and especially by floods, requires the development of effective evacuation systems. An effective evacuation system must take into account certain constraints, including those related to traffic network, accessibility, human resources and material equipment (vehicles, collecting points, etc.). The main objective of this work is to provide assistance to technical services and rescue forces in terms of accessibility by offering itineraries relating to rescue and evacuation of people and property. We consider in this paper the evacuation of an urban area of medium size exposed to the hazard of flood. In case of inundation, most people will be evacuated using their own vehicles. Two evacuation types are addressed in this paper: (1) a preventive evacuation based on a flood forecasting system and (2) an evacuation during the disaster based on flooding scenarios. The two study sites on which the developed evacuation model is applied are the Tours valley (Fr, 37), which is protected by a set of dikes (preventive evacuation), and the Gien valley (Fr, 45), which benefits from a low rate of flooding (evacuation before and during the disaster). Our goal is to construct, for each of these two sites, a chronological evacuation plan, i.e., computing for each individual the departure date and the path to reach the assembly point (also called shelter) according to a priority list established for this purpose. The evacuation plan must avoid the congestion on the road network. Here we present a spatiotemporal optimization model (STOM) dedicated to the evacuation of the population exposed to natural disasters and more specifically to flood risk.

  12. A spatio-temporel optimization model for the evacuation of the population exposed to natural disasters

    Science.gov (United States)

    Alaeddine, H.; Serrhini, K.; Maïzia, M.; Néron, E.

    2015-01-01

    The importance of managing the crisis caused by natural disasters, and especially by flood, requires the development of an effective evacuation systems. An effective evacuation system must take into account certain constraints, including those related to network traffic, accessibility, human resources and material equipment (vehicles, collecting points, etc.). The main objective of this work is to provide assistance to technical services and rescue forces in terms of accessibility by offering itineraries relating to rescue and evacuation of people and property. We consider in this paper the evacuation of an urban area of medium size exposed to the hazard of flood. In case of inundation, most people will be evacuated using their own vehicles. Two evacuation types are addressed in this paper, (1) a preventive evacuation based on a flood forecasting system and (2) an evacuation during the disaster based on flooding scenarios. The two study sites on which the evacuation model developed is applied are the valley of Tours (Fr, 37) which is protected by a set of dikes (preventive evacuation) and the valley of Gien (Fr, 45) which benefits of a low rate of flooding (evacuation before and during the disaster). Our goal is to construct, for each of these two sites, a chronological evacuation plan i.e. computing for each individual the departure date and the path to reach the assembly point (also called shelter) associated according to a priorities list established for this purpose. Evacuation plan must avoid the congestion on the road network. Here we present a Spatio-Temporal Optimization Model (STOM) dedicated to the evacuation of the population exposed to natural disasters and more specifically to flood risk.

  13. Tsunami Evacuation Exercises: the Case of Heraklion, Crete Isl., Greece

    Science.gov (United States)

    Triantafyllou, I.; Charalampakis, M.; Bocchini, G. M.; Novikova, T.; Papadopoulos, G. A.

    2016-12-01

    Effective tsunami evacuation requires appropriate awareness as regards good shelters selection. Field exercises may improve public awareness. A field exercise was organized in Heraklion, Crete Isl., in 2016. The area is part of the Hellenic Arc which is the most active structure in the Mediterranean. Large earthquakes triggered tsunamis that hit Heraklion in the past, such in AD 1303. After selecting various fault models, simulation of the 1303 tsunami showed important inundation zone in Heraklion. For the exercise needs a team of 30 volunteers was divided in 3 groups of 10 people each. Everyone was equipped with a mobile phone and a GPS device. The 3 groups were gathered in 3 coastal spots Heraklion situated 400 m apart each other. The scenario was that immediately after receiving in their mobile a tsunami warning message they will set on their personal GPS device and start evacuating inland on the best way they believed to do so. In each group, only 5 out of 10 volunteers were notified beforehand that the Eleftherias Square, located inland at distance satisfying evacuation needs in case of repeat of the 1303 tsunami, would be a good shelter to go. Using the Road Graph Plugin of QGIS, we calculated the shortest path distances which found equal to 800, 700 and 680 m. Adopting average velocity of 3 km/h we found that these distances can be covered within 18, 16 and 15 min, respectively. The routes towards the settlement spots as well as the times needed to arrive there by each one of the 30 volunteers were recorded by their personal GPS devices. The processing of the GPS tracks and their comparison with the theoretical routes and times showed good evacuation performance which is encouraging for the next phases of the Heraklion tsunami hazard mitigation program. This is contribution to the EU-FP7 projects ZIP (Zooming In between Plates, grant no: 604713, 2013) and ASTARTE (Assessment, Strategy And Risk Reduction for Tsunamis in Europe), grant no: 603839, 2013.

  14. Emergency Evacuation of Hazardous Chemical Accidents Based on Diffusion Simulation

    OpenAIRE

    Jiang-Hua Zhang; Hai-Yue Liu; Rui Zhu; Yang Liu

    2017-01-01

    The recent rapid development of information technology, such as sensing technology, communications technology, and database, allows us to use simulation experiments for analyzing serious accidents caused by hazardous chemicals. Due to the toxicity and diffusion of hazardous chemicals, these accidents often lead to not only severe consequences and economic losses, but also traffic jams at the same time. Emergency evacuation after hazardous chemical accidents is an effective means to reduce the...

  15. Fatigue Life of High-Strength Steel Offshore Tubular Joints

    DEFF Research Database (Denmark)

    Petersen, Rasmus Ingomar; Agerskov, Henning; Lopez Martinez, Luis

    1996-01-01

    In the present investigation, the fatigue life of tubular joints in offshore steel structures is studied. Two test series on full-scale tubular joints have been carried through. One series was on joints in conventional offshore structural steel, and the other series was on joints in high-strength......In the present investigation, the fatigue life of tubular joints in offshore steel structures is studied. Two test series on full-scale tubular joints have been carried through. One series was on joints in conventional offshore structural steel, and the other series was on joints in high......-strength steel with a yield stress of 820-830 MPa and with high weldability and toughness properties. The test specimens of both series had the same geometry. The present report concentrates on the results obtained in the investigation on the high-strength steel tubular joints.The test specimens were fabricated...... from Ø 324-610 mm tubes, and the joints were loaded in in-plane bending. Both fatigue tests under constant amplitude loading and tests with a stochastic loading that is realistic in relation to offshore structures, are included in the investigation.A comparison between constant amplitude and variable...

  16. Mathematical rationalization for the renal tubular transport: revised concepts.

    Science.gov (United States)

    Mioni, Roberto; Marega, Alessandra; Romano, Giulio; Montanaro, Domenico

    2017-09-01

    The current emphasis on kinetics and in situ control of molecular exchanges, across the tubular membrane, has not been paralleled by corresponding improvements in our understanding of tubular behaviour at the macroscopic level of classical physiology. In this paper, we propose a mathematical rationalization of macroscopic tubular transport by means of a principal transport equation, originating from the law of mass action between substrate and carrier. The other equations, derived from the main one, demonstrate the possibility of distinguishing between transporters with low affinity and high capacity and transporters with high affinity and low capacity. Moreover, our model formalizes both tubular reabsorption and tubular secretion. Regarding the renal calcium handling, our model confirms the two-compartment system proposed by Mioni in 1971, with some important variants, which are in agreement with the fractional reabsorptions of this cation along the tubule, as verified by micro-puncture technique. To obtain the frequency distribution of saturated tubules, we have utilized the infinitesimal analysis method, starting from the equations proposed by Smith in 1943, concluding that all titration curves result from the combined effect of enzymatic approach and anatomical heterogeneity of the nephrons. The theoretical equations included in our manuscript reflect substantial and palpable physiological mechanisms able to suggest diagnosis and therapy of some electrolyte and hormonal disorders. At the end of this paper, we highlight advantages and disadvantages detectable by comparing our mathematical approach with Marshall's and Bijvoet's methods, proposed, respectively, in 1976 and 1984.

  17. Proximal tubular dysfunction as an indicator of chronic graft dysfunction

    Directory of Open Access Journals (Sweden)

    N.O.S. Câmara

    2009-03-01

    Full Text Available New strategies are being devised to limit the impact of renal sclerosis on graft function. Individualization of immunosuppression, specifically the interruption of calcineurin-inhibitors has been tried in order to promote better graft survival once chronic graft dysfunction has been established. However, the long-term impact of these approaches is still not totally clear. Nevertheless, patients at higher risk for tubular atrophy and interstitial fibrosis (TA/IF development should be carefully monitored for tubular function as well as glomerular performance. Since tubular-interstitial impairment is an early event in TA/IF pathogenesis and associated with graft function, it seems reasonable that strategies directed at assessing tubular structural integrity and function would yield important functional and prognostic data. The measurement of small proteins in urine such as α-1-microglobulin, N-acetyl-beta-D-glucosaminidase, alpha/pi S-glutathione transferases, β-2 microglobulin, and retinol binding protein is associated with proximal tubular cell dysfunction. Therefore, its straightforward assessment could provide a powerful tool in patient monitoring and ongoing clinical assessment of graft function, ultimately helping to facilitate longer patient and graft survival associated with good graft function.

  18. Assessment of Evacuation Protective Action Strategies For Emergency Preparedness Plan

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Joomyung; Jae, Moosung [Hanyang Univ., Seoul (Korea, Republic of); Ahn, Kwangil [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-10-15

    This report which studies about evacuation formation suggests some considerable factors to reduce damage of radiological accidents. Additional details would be required to study in depth and more elements should be considered for updating emergency preparedness. However, this methodology with sensitivity analysis could adapt to specific plant which has total information such as geological data, weather data and population data. In this point of view the evacuation study could be contribute to set up emergency preparedness plan and propose the direction to enhance protective action strategies. In radiological emergency, residents nearby nuclear power plant should perform protective action that is suggested by emergency preparedness plan. The objective of emergency preparedness plan is that damages, such as casualties and environmental damages, due to radioactive accident should be minimized. The recent PAR study includes a number of subjects to improve the quality of protective action strategies. For enhancing protective action strategies, researches that evaluate many factors related with emergency response scenario are essential parts to update emergency preparedness plan. Evacuation is very important response action as protective action strategy.

  19. Assessment of Evacuation Protective Action Strategies For Emergency Preparedness Plan

    International Nuclear Information System (INIS)

    Lee, Joomyung; Jae, Moosung; Ahn, Kwangil

    2013-01-01

    This report which studies about evacuation formation suggests some considerable factors to reduce damage of radiological accidents. Additional details would be required to study in depth and more elements should be considered for updating emergency preparedness. However, this methodology with sensitivity analysis could adapt to specific plant which has total information such as geological data, weather data and population data. In this point of view the evacuation study could be contribute to set up emergency preparedness plan and propose the direction to enhance protective action strategies. In radiological emergency, residents nearby nuclear power plant should perform protective action that is suggested by emergency preparedness plan. The objective of emergency preparedness plan is that damages, such as casualties and environmental damages, due to radioactive accident should be minimized. The recent PAR study includes a number of subjects to improve the quality of protective action strategies. For enhancing protective action strategies, researches that evaluate many factors related with emergency response scenario are essential parts to update emergency preparedness plan. Evacuation is very important response action as protective action strategy

  20. Case series: Bladder clot evacuation using a prostate morcellation device.

    Science.gov (United States)

    Doersch, Karen M; Navetta, Andrew F; Bird, Erin T; El Tayeb, Marawan M

    2017-07-01

    We sought to provide a technical update on the use of a prostate morcellator device (PMD) to manage organized blood clots of the bladder following laser prostatectomy. Herein, we describe our experience in using the Wolf Piranha morcellator in managing organized bladder blood clots supplemented with a retrospective chart review of the patients in whom this procedure was performed. Six patients, all male with a mean age of 75 ± 8.9 years, had organized bladder clots following either holmium laser enucleation or photoselective vaporization of the prostate managed with a PMD. Clots were recognized based on hematuria or urinary retention a median of 3.5 days following the aforementioned procedures. Initial management was attempted with more conservative measures, including a three-way Foley catheter, followed by cystoscopy with an Ellik evacuator, or a glass Tommey syringe. Morcellation times were a mean of 10.2 ± 6.15 minutes (range 2-18). This technique was able to manage clots that were an average of 173.3 ± 115.9 cc in size. The procedure was well-tolerated. No patients experienced intraoperative or morcellator-related complications. Benign prostatic hypertrophy frequently requires surgical endoscopic management and can be complicated by hematuria and bladder blood clot formation. When these clots become organized, this can lead to urinary retention and the required management, evacuation, may be difficult. The use of a Wolf Piranha PMD is a safe, well-tolerated, and effective in evacuating organized blood clots of the bladder.

  1. Pedestrians’ behavior in emergency evacuation: Modeling and simulation

    Science.gov (United States)

    Wang, Lei; Zheng, Jie-Hui; Zhang, Xiao-Shuang; Zhang, Jian-Lin; Wang, Qiu-Zhen; Zhang, Qian

    2016-11-01

    The social force model has been widely used to simulate pedestrian evacuation by analyzing attractive, repulsive, driving, and fluctuating forces among pedestrians. Many researchers have improved its limitations in simulating behaviors of large-scale population. This study modifies the well-accepted social force model by considering the impacts of interaction among companions and further develops a comprehensive model by combining that with a multi-exit utility function. Then numerical simulations of evacuations based on the comprehensive model are implemented in the waiting hall of the Wulin Square Subway Station in Hangzhou, China. The results provide safety thresholds of pedestrian density and panic levels in different operation situations. In spite of the operation situation and the panic level, a larger friend-group size results in lower evacuation efficiency. Our study makes important contributions to building a comprehensive multi-exit social force model and to applying it to actual scenarios, which produces data to facilitate decision making in contingency plans and emergency treatment. Project supported by the National Natural Science Foundation of China (Grant No. 71471163).

  2. Short-time home coming project in evacuation zone

    International Nuclear Information System (INIS)

    Tatsuzaki, Hideo

    2011-01-01

    Accident at Fukushima Daiichi Nuclear Power Plants (NPPs) forced neighboring residents to evacuate, and evacuation zone (20 km radius from NPPs) was defined as highly contaminated and designated as no-entry zones. Residents had been obliged to live a refugee life for a longer period than expected. Short-time home coming project was initiated according to their requests. They came to the meeting place called transfer place (20 - 30 km radius from NPPs), wore protective clothing and personal dosimeter with having drinking water and came home in evacuation zone with staffs by bus. Their healthcare management professionals were fully prepared for emergency. After collecting necessary articles at home within two hours, they returned to the meeting place by bus for screening and dressing, and went back to refuge house. If screening data were greater than 13 kcpm using GM counters, partial body decontamination had been conducted by wiping and if greater than 100 kcpm, whole body decontamination was requested but not conducted. Dose rate of residents and staffs was controlled less than 1 mSv, which was alarm level of personal dosimeter. Stable iodine was prepared but actually not used. (T. Tanaka)

  3. Flexible endoscope-assisted evacuation of chronic subdural hematomas.

    Science.gov (United States)

    Májovský, Martin; Masopust, Václav; Netuka, David; Beneš, Vladimír

    2016-10-01

    Chronic subdural hematoma (CSDH) is a common neurosurgical condition with an increasing incidence. Standard treatment of CSDHs is surgical evacuation. The objective of this study is to present a modification of standard burr-hole hematoma evacuation using a flexible endoscope and to assess the advantages and risks. Prospectively, 34 consecutive patients diagnosed with CSDH were included in the study. Epidemiological, clinical and radiographical data were collected and reviewed. All patients underwent a burr-hole evacuation of CSDH. A flexible endoscope was inserted and subdural space inspected during surgery. The surgeon was looking specifically for the presence of septations, draining catheter position and acute bleeding. Thirty-four patients underwent 37 endoscope-assisted surgeries. Presenting symptoms were hemiparesis (79%), decreased level of consciousness (18%), gait disturbances (15%), headache (12%), aphasia (6%), cognitive disturbances (6%) and epileptic seizure (3%). Average operative time was 43 min, and the average increase in operative time due to the use of the endoscope was 6 min. Recurrence rate was 8.8%, and clinical outcome was favorable (defined as mRS ≤ 2) in 97% of the cases. To our knowledge, the present cohort of 34 patients is the largest group of patients with CSDH treated using an endoscope. This technique allows decent visualization of the hematoma cavity while retaining the advantages of a minimally invasive approach under a local anesthesia. The main advantages are correct positioning of the catheter under visual control, identification of septations and early detection of cortex or vessel injury during surgery.

  4. Emergency Evacuation of Hazardous Chemical Accidents Based on Diffusion Simulation

    Directory of Open Access Journals (Sweden)

    Jiang-Hua Zhang

    2017-01-01

    Full Text Available The recent rapid development of information technology, such as sensing technology, communications technology, and database, allows us to use simulation experiments for analyzing serious accidents caused by hazardous chemicals. Due to the toxicity and diffusion of hazardous chemicals, these accidents often lead to not only severe consequences and economic losses, but also traffic jams at the same time. Emergency evacuation after hazardous chemical accidents is an effective means to reduce the loss of life and property and to smoothly resume the transport network as soon as possible. This paper considers the dynamic changes of the hazardous chemicals’ concentration after their leakage and simulates the diffusion process. Based on the characteristics of emergency evacuation of hazardous chemical accidents, we build a mixed-integer programming model and design a heuristic algorithm using network optimization and diffusion simulation (hereafter NODS. We then verify the validity and feasibility of the algorithm using Jinan, China, as a computational example. In the end, we compare the results from different scenarios to explore the key factors affecting the effectiveness of the evacuation process.

  5. Medical Evacuation from Vietnam of an Elderly with Tuberculosis Spondylitis

    Directory of Open Access Journals (Sweden)

    Ying-Hua Shieh

    2007-09-01

    Full Text Available Despite the growth in economy in Vietnam, the infrastructure of dependable medical care is still lacking. Therefore, aeromedical evacuation of patients to other countries for further medical interventions has become an important medical service in the region. We report a case where an elderly man who was aeromedically evacuated from Ho Chi Minh City, Vietnam to Taipei Medical University–Municipal Wan Fang Hospital in Taipei, Taiwan. The patient developed a sudden onset of quadriplegia because of an epidural abscess at the cervical spine C6–C7. Antituberculous medication was prescribed for suspected tuberculous spondylitis, because his cerebral spinal fluid showed elevated white blood cells with a predominance of lymphocytes, and mildly elevated total protein. However, whole body tumor scan (67Ga mCi and whole body bone scan (99mTc methylene diphosphonate, 25 mCi did not reveal any specific results. Surgical intervention was arranged because of cervical spine instability and the need for a diagnostic biopsy. Adenocarcinoma of the prostate was found incidentally and was treated with bilateral orchiectomy and radiation therapy. This was the first medical evacuation by the Family Medical Practice group in Ho Chi Minh City, Vietnam to Taiwan.

  6. Low-temperature operating regime of the tokamak evacuating limiter

    International Nuclear Information System (INIS)

    Tokar', M.Z.

    1987-01-01

    The conditions for realizing the regime of strong recycling of a cold dense plasma of an evacuating limiter were determined based on a previously proposed model for describing the limiter layer of a tokamak. The scaling for the dependence of the gas pressure in the evacuation system on the average plasma density in the limiter layer was found, and agreed quantitatively with the results of measurements on the Alcator and ISX-B tokamaks. For the tokamak reactor of the INTOR scale the calculations show that the low-temperature operating regime of the evacuating limiter can be realized with a quite low pumping rate. It has the advantages of reduced erosion of the limiter and small fluxes of impurities into the working volume of the reactor. In addition, the relative concentration of the helium ash in the limiter layer does not exceed 2-3%, but the density of the main plasma is comparable to the proposed average density in the reactor. The concept of a stochastic limiter is of interest for lowering the plasma density in the limiter layer and lowering the thermal loads on the limiter

  7. Measuring and modeling behavioral decision dynamics in collective evacuation.

    Directory of Open Access Journals (Sweden)

    Jean M Carlson

    Full Text Available Identifying and quantifying factors influencing human decision making remains an outstanding challenge, impacting the performance and predictability of social and technological systems. In many cases, system failures are traced to human factors including congestion, overload, miscommunication, and delays. Here we report results of a behavioral network science experiment, targeting decision making in a natural disaster. In a controlled laboratory setting, our results quantify several key factors influencing individual evacuation decision making in a controlled laboratory setting. The experiment includes tensions between broadcast and peer-to-peer information, and contrasts the effects of temporal urgency associated with the imminence of the disaster and the effects of limited shelter capacity for evacuees. Based on empirical measurements of the cumulative rate of evacuations as a function of the instantaneous disaster likelihood, we develop a quantitative model for decision making that captures remarkably well the main features of observed collective behavior across many different scenarios. Moreover, this model captures the sensitivity of individual- and population-level decision behaviors to external pressures, and systematic deviations from the model provide meaningful estimates of variability in the collective response. Identification of robust methods for quantifying human decisions in the face of risk has implications for policy in disasters and other threat scenarios, specifically the development and testing of robust strategies for training and control of evacuations that account for human behavior and network topologies.

  8. Proactive Traffic Information Control in Emergency Evacuation Network

    Directory of Open Access Journals (Sweden)

    Zhengfeng Huang

    2015-01-01

    Full Text Available Traffic demand in emergency evacuation is usually too large to be effectively managed with reactive traffic information control methods. These methods adapt to the road traffic passively by publishing real-time information without consideration of the routing behavior feedback produced by evacuees. Other remedy measures have to be prepared in case of nonrecurring congestion under these methods. To use the network capacity fully to mitigate near-future evacuation traffic congestion, we propose proactive traffic information control (PTIC model. Based on the mechanism between information and routing behavior feedback, this model can change the route choice of evacuees in advance by dissipating strategic traffic information. Generally, the near-future traffic condition is difficult to accurately predict because it is uncertain in evacuation. Assume that the value of traffic information obeys certain distribution within a range, and then real-time traffic information may reflect the most-likely near-future traffic condition. Unlike the real-time information, the proactive traffic information is a selection within the range to achieve a desired level of the road network performance index (total system travel time. In the aspect of the solution algorithm, differential equilibrium decomposed optimization (D-EDO is proposed to compare with other heuristic methods. A field study on a road network around a large stadium is used to validate the PTIC.

  9. An evaluation of sharp safety blood evacuation devices.

    Science.gov (United States)

    Ford, Joanna; Phillips, Peter

    This article describes an evaluation of three sharp safety blood evacuation devices in seven Welsh NHS boards and the Welsh Blood Service. Products consisted of two phlebotomy needles possessing safety shields and one phlebotomy device with wings, tubing and a retractable needle. The device companies provided the devices and appropriate training. Participating healthcare workers used the safety device instead of the conventional device to sample blood during the evaluation period and each type of device was evaluated in random order. Participants filled in a questionnaire for each type of device and then a further questionnaire comparing the two shielded evacuation needles with each other Results showed that responses to all three products were fairly positive, although each device was not liked by everyone who used it. When the two shielded evacuation devices were compared with each other, most users preferred the device with the shield positioned directly above the needle to the device with the shield at the side. However, in laboratory tests, the preferred device produced more fluid splatter than the other shielded device on activation.

  10. Performance of non-conventional solar collectors in local market of Nawabshah

    International Nuclear Information System (INIS)

    Memon, M.; Tanwani, N.K.; Memon, A.H.

    1998-01-01

    This paper presents experimental studies concerning the performance of solar collectors using sand-bed as absorbing surface and a collector. These collectors were designed, manufactured locally and tested in meteorological conditions of Nawabshah, Sindh, Pakistan. The ordinary tap water was used as working fluid and tests were carried out in open space during day time. The effect of collector area and tubing diameter on collector performance was investigated. For each test run ambient, inlet and outlet water temperature together with flow rate of collector fluid was recorded. Two collectors connected in series showed an increase of about 20 deg. C in outlet temperature of water. Thus an average increase of 15 deg. C in the temperature was observed for each collector. The temperature was raised to 90 deg. C using the concentrator in combination with the two non-conventional flat collectors. (author)

  11. Optimum tilt angle and orientation for solar collectors in Syria

    International Nuclear Information System (INIS)

    Skeiker, Kamal

    2009-01-01

    One of the important parameters that affect the performance of a solar collector is its tilt angle with the horizon. This is because of the variation of tilt angle changes the amount of solar radiation reaching the collector surface. A mathematical model was used for estimating the solar radiation on a tilted surface, and to determine the optimum tilt angle and orientation (surface azimuth angle) for the solar collector in the main Syrian zones, on a daily basis, as well as for a specific period. The optimum angle was computed by searching for the values for which the radiation on the collector surface is a maximum for a particular day or a specific period. The results reveal that changing the tilt angle 12 times in a year (i.e. using the monthly optimum tilt angle) maintains approximately the total amount of solar radiation near the maximum value that is found by changing the tilt angle daily to its optimum value. This achieves a yearly gain in solar radiation of approximately 30% more than the case of a solar collector fixed on a horizontal surface.

  12. Commissioning a Megawatt-class Gyrotron with Collector Potential Depression

    Science.gov (United States)

    Lohr, J.; Cengher, M.; Gorelov, Y. A.; Ponce, D.; Prater, R.

    2013-10-01

    A 110 GHz depressed collector gyrotron has been installed on the DIII-D tokamak. The commissioning process rapidly achieved operation at full parameters, 45 A and 94 kV total voltage, with 29 kV depression. Although short pulse, 2 ms, factory testing demonstrated 1.2 MW at 41% electrical efficiency, long pulse testing at DIII-D achieved only 33% efficiency at full power parameters, for pulse lengths up to 10 s. Maximum generated power was ~950 kW, considerably below the 1.2 MW target. During attempts to increase the power at 5 s pulse length, it was noted that the collector cooling water was boiling. This led to the discovery that 14 of the 160 cooling channels in the collector had been blocked by braze material during manufacture of the tube. The locations of blocked channels were identified using infrared imaging of the outside of the collector during rapid changes in the cooling water temperature. Despite these difficulties, the rf beam itself was of very high quality and the stray rf found calorimetrically in the Matching Optics Unit, which couples the Gaussian rf beam to the waveguide, was only 2% of the generated power, about half that of our previous best quality high power beam. Details of the power measurements and collector observations will be presented. Work supported by the US DOE under DE-FC02-04ER54698.

  13. Performance of direct absorption solar collector with nanofluid mixture

    International Nuclear Information System (INIS)

    Turkyilmazoglu, Mustafa

    2016-01-01

    Highlights: • Neat approximations for temperature and solar collector efficiency are presented. • The non-adiabatic and isothermal base mechanisms optimize the surface absorption. • Heat transferring material at the bottom panel enhances the thermal efficiency. • Isothermal base panel leads to maximum thermal efficiency of the solar receiver. - Abstract: The enhancement of performance by increasing the thermal efficiency of a direct absorption solar collector based on an alumina–water nanofluid is the prime target of the present research. The base panel of the collector channel is subject to either a non adiabatic or an isothermal wall condition both of which introduce two new physical parameters. Analytical solutions for the temperature field are worked out in both cases for a two dimensional steady-state model recently outlined in the literature. The desired increase in the temperature of the heat transferring nanofluid is achieved either by slightly rising the heat transfer coefficient of the bottom panel coating or by prescribing a bottom surface temperature. As a consequence of the increase in the final outlet mean temperature, the solar collector thermal efficiency is found to be enhanced via increasing the new physical parameters as compared to the traditional adiabatic wall case. For instance, 85.63% thermal efficiency of solar collector is achievable for non adiabatic bottom panel by adding suspended aluminum nanoparticles into the pure water. Even better than this, considering isothermal base panels, 100% efficiency is attained more rapidly with lesser base temperatures in the presence of higher nanoparticle volume fractions.

  14. Integrated collector storage solar water heater: Temperature stratification

    International Nuclear Information System (INIS)

    Garnier, C.; Currie, J.; Muneer, T.

    2009-01-01

    An analysis of the temperature stratification inside an Integrated Collector Storage Solar Water Heater (ICS-SWH) was carried out. The system takes the form of a rectangular-shaped box incorporating the solar collector and storage tank into a single unit and was optimised for simulation in Scottish weather conditions. A 3-month experimental study on the ICS-SWH was undertaken in order to provide empirical data for comparison with the computed results. Using a previously developed macro model; a number of improvements were made. The initial macro model was able to generate corresponding water bulk temperature in the collector with a given hourly incident solar radiation, ambient temperature and inlet water temperature and therefore able to predict ICS-SWH performance. The new model was able to compute the bulk water temperature variation in different SWH collectors for a given aspect ratio and the water temperature along the height of the collector (temperature stratification). Computed longitudinal temperature stratification results obtained were found to be in close agreement with the experimental data.

  15. Performance analysis of photovoltaic thermal (PVT) water collectors

    International Nuclear Information System (INIS)

    Fudholi, Ahmad; Sopian, Kamaruzzaman; Yazdi, Mohammad H.; Ruslan, Mohd Hafidz; Ibrahim, Adnan; Kazem, Hussein A.

    2014-01-01

    Highlights: • Performances analysis of PVT collector based on energy efficiencies. • New absorber designs of PVT collectors were presented. • Comparison present study with other absorber collector designs was presented. • High efficiencies were obtained for spiral flow absorber. - Abstract: The electrical and thermal performances of photovoltaic thermal (PVT) water collectors were determined under 500–800 W/m 2 solar radiation levels. At each solar radiation level, mass flow rates ranging from 0.011 kg/s to 0.041 kg/s were introduced. The PVT collectors were tested with respect to PV efficiency, thermal efficiency, and a combination of both (PVT efficiency). The results show that the spiral flow absorber exhibited the highest performance at a solar radiation level of 800 W/m 2 and mass flow rate of 0.041 kg/s. This absorber produced a PVT efficiency of 68.4%, a PV efficiency of 13.8%, and a thermal efficiency of 54.6%. It also produced a primary-energy saving efficiency ranging from 79% to 91% at a mass flow rate of 0.011–0.041 kg/s

  16. Effect of the collector tube profile on Pitot pump performances

    Science.gov (United States)

    Komaki, K.; Kanemoto, T.; Sagara, K.; Umekage, T.

    2013-12-01

    The pitot pump is composed of the rotating casing with the impeller channel and the pitot tube type collector as the discharge line. The radial impeller feeds water to the rotating casing. The water rotating together with the casing is caught by the stationary pitot tube type collector, and then discharges to the outside. This type pump, as the extra high head pump, is provided mainly for boiler feed systems, and has been designed by trial and error. To optimize the pump profiles, it is desirable to investigate not only performances but also internal flow conditions. This paper discusses experimentally and numerically the relation between the pump performances and the flow conditions in the rotating casing. The moderately larger dimensions of the collector make the pump head and the discharge high with the higher hydraulic efficiency. The flow in the casing is almost the forced vortex type whose velocity is in proportion to the radius but the core velocity is affected with the drag force of the stationary collector. Based upon the above results, the profile of the pitot tube type collector was optimized with the numerical simulation.

  17. Effect of the collector tube profile on Pitot pump performances

    International Nuclear Information System (INIS)

    Komaki, K; Sagara, K; Kanemoto, T; Umekage, T

    2013-01-01

    The pitot pump is composed of the rotating casing with the impeller channel and the pitot tube type collector as the discharge line. The radial impeller feeds water to the rotating casing. The water rotating together with the casing is caught by the stationary pitot tube type collector, and then discharges to the outside. This type pump, as the extra high head pump, is provided mainly for boiler feed systems, and has been designed by trial and error. To optimize the pump profiles, it is desirable to investigate not only performances but also internal flow conditions. This paper discusses experimentally and numerically the relation between the pump performances and the flow conditions in the rotating casing. The moderately larger dimensions of the collector make the pump head and the discharge high with the higher hydraulic efficiency. The flow in the casing is almost the forced vortex type whose velocity is in proportion to the radius but the core velocity is affected with the drag force of the stationary collector. Based upon the above results, the profile of the pitot tube type collector was optimized with the numerical simulation

  18. Optimization of the functional domain of flat plate collectors

    Science.gov (United States)

    Ritoux, G.; Irigaray, J.-L.

    1981-12-01

    The variations of the extracted heat flux as function of the temperature of the heat transfer fluid in black and selective surface solar collectors are examined. The heat flux is calculated based on the difference of the initial to the stage of thermal equilibrium of the fluid. A nonlinear system of equations is developed and solved by a fast, iterative method to obtain the equilibrium temperatures. It is found that more flux can be extracted from the solar heat by a collector with only one glass cover than with more than one cover. The captured flux is proportional to the coefficient of transmission of the glass coverings, to the coefficient of absorption of the collector, and to the incident flux. Black painted surfaces were more absorbent than selective surfaces, and highest collection efficiencies were displayed by low temperature collectors. Charts of effective uses of the respective types of collectors for heating swimming pools, hot water, home heat, and for refrigeration and air-conditioning are provided.

  19. Wide bandgap collector III-V double heterojunction bipolar transistors

    International Nuclear Information System (INIS)

    Flitcroft, R.M.

    2000-10-01

    This thesis is devoted to the study and development of Heterojunction Bipolar Transistors (HBTs) designed for high voltage operation. The work concentrates on the use of wide bandgap III-V semiconductor materials as the collector material and their associated properties influencing breakdown, such as impact ionisation coefficients. The work deals with issues related to incorporating a wide bandgap collector into double heterojunction structures such as conduction band discontinuities at the base-collector junction and results are presented which detail, a number of methods designed to eliminate the effects of such discontinuities. In particular the use of AlGaAs as the base material has been successful in eliminating the conduction band spike at this interface. A method of electrically injecting electrons into the collector has been employed to investigate impact ionisation in GaAs, GaInP and AlInP which has used the intrinsic gain of the devices to extract impact ionisation coefficients over a range of electric fields beyond the scope of conventional optical injection techniques. This data has enabled the study of ''dead space'' effects in HBT collectors and have been used to develop an analytical model of impact ionisation which has been incorporated into an existing Ebers-Moll HBT simulator. This simulator has been shown to accurately reproduce current-voltage characteristics in both the devices used in this work and for external clients. (author)

  20. Why Don't People Evacuate When Nature Threatens?

    Science.gov (United States)

    Thompson, K. J.; Broad, K.; Meyer, R.; Orlove, B. S.

    2011-12-01

    Why do so many Southern Californians fail to evacuate when warned that winter storms have critically raised the risk of a debris flow in their neighborhoods? Have they perhaps not seen or heeded news coverage of past debris flow events? Are they unaware that recent fires made the hillsides above them more prone to gravity-driven processes? Do they think they can wait to start their cars until they can actually see the flow coming? Or have they merely experienced too many "false alarms" in past years, and no longer put much stock in the judgment of public officials or the ability of scientists to judge debris flow risk? In preparation for a simulation study that will place decision makers in a virtual house in the California foothills during a winter storm event, we explore the reasons that people do and do not evacuate in the face of potential debris flows. Working in collaboration with the USGS Multi-Hazards Demonstration Project for Southern California, we are surveying hundreds of local residents, from debris-flow prone areas and from elsewhere in the state, to establish their baseline knowledge (and misconceptions) about, attitudes toward, information use regarding, and experience with debris flows. Initial interviews with residents of recently hit neighborhoods give qualitative data suggesting that false-alarm effects and underestimation of risk are driving factors; these surveys will provide quantitative evidence to extend those findings. We will discuss the results of this survey in the context of a comprehensive body of psychology research that seeks to explain why people frequently appear to ignore or discount hazard warnings: neglecting to insure their homes and crops (Kunreuther, 1984), failing to evacuate in the face of storms and fires (Baker, 1991; Packham, 1995), and (barring a recent, vivid event) showing little support for measures that would manage or mitigate future hazards (Kunreuther, 2006a, 2006b; Weber, 2006). We will also consider the

  1. Emergent patterns of collective cell migration under tubular confinement.

    Science.gov (United States)

    Xi, Wang; Sonam, Surabhi; Beng Saw, Thuan; Ladoux, Benoit; Teck Lim, Chwee

    2017-11-15

    Collective epithelial behaviors are essential for the development of lumens in organs. However, conventional assays of planar systems fail to replicate cell cohorts of tubular structures that advance in concerted ways on out-of-plane curved and confined surfaces, such as ductal elongation in vivo. Here, we mimic such coordinated tissue migration by forming lumens of epithelial cell sheets inside microtubes of 1-10 cell lengths in diameter. We show that these cell tubes reproduce the physiological apical-basal polarity, and have actin alignment, cell orientation, tissue organization, and migration modes that depend on the extent of tubular confinement and/or curvature. In contrast to flat constraint, the cell sheets in a highly constricted smaller microtube demonstrate slow motion with periodic relaxation, but fast overall movement in large microtubes. Altogether, our findings provide insights into the emerging migratory modes for epithelial migration and growth under tubular confinement, which are reminiscent of the in vivo scenario.

  2. Power generation characteristics of tubular type SOFC by wet process

    Energy Technology Data Exchange (ETDEWEB)

    Tajiri, H.; Nakayama, T. [Kyushu Electric Power Company, Inc., Fukuoka (Japan); Kuroishi, M. [TOTO Ltd., Kanagawa (Japan)] [and others

    1996-12-31

    The development of a practical solid oxide fuel cell requires improvement of a cell performance and a cell manufacturing technology suitable for the mass production. In particular tubular type SOFC is thought to be superior in its reliability because its configuration can avoid the high temperature sealing and reduce the thermal stress resulting from the contact between cells. The authors have fabricated a tubular cell with an air electrode support by a wet processing technique, which is suitable for mass production in improving a power density. To enhance the power output of the module, the Integrated Tubular-Type (ITT) cell has been developed. This paper reports the performance of the single cells with various active anode areas and the bundle with series-connected 9-ITT cells with an active anode area of 840 cm{sup 2}.

  3. Effect of corrosion on the buckling capacity of tubular members

    Science.gov (United States)

    Øyasæter, F. H.; Aeran, A.; Siriwardane, S. C.; Mikkelsen, O.

    2017-12-01

    Offshore installations are subjected to harsh marine environment and often have damages from corrosion. Several experimental and numerical studies were performed in the past to estimate buckling capacity of corroded tubular members. However, these studies were either based on limited experimental tests or numerical analyses of few cases resulting in semi-empirical relations. Also, there are no guidelines and recommendations in the currently available design standards. To fulfil this research gap, a new formula is proposed to estimate the residual strength of tubular members considering corrosion and initial geometrical imperfections. The proposed formula is verified with results from finite element analyses performed on several members and for varying corrosion patch parameters. The members are selected to represent the most relevant Eurocode buckling curve for tubular members. It is concluded that corrosion reduces the buckling capacity significantly and the proposed formula can be easily applied by practicing engineers without performing detailed numerical analyses.

  4. HER-2 amplification in tubular carcinoma of the breast.

    Science.gov (United States)

    Oakley, Gerard J; Tubbs, Raymond R; Crowe, Joseph; Sebek, Bruce; Budd, G Thomas; Patrick, Rebecca J; Procop, Gary W

    2006-07-01

    The prognostic and therapeutic implications of HER-2 gene amplification and estrogen and progesterone receptor status in breast cancer are well described. To address the relative paucity of information concerning HER-2 amplification for tubular carcinomas, we assessed the frequency of gene amplification in 55 tubular carcinomas of the breast from 54 patients, 5 of which had axillary node metastases. The HER-2 gene copy number was assessed by fluorescence in situ hybridization for the majority of tumors analyzed, whereas estrogen and progesterone receptor status was achieved by immunohistochemical analysis. HER-2 gene amplification was not observed in any of the tumors examined, and most were estrogen receptor-positive. This HER-2 gene amplification frequency was significantly lower than the frequency of gene amplification previously reported for all invasive ductal carcinoma of no special type (P < .01). HER-2 gene amplification likely occurs infrequently, or not at all, in tubular carcinomas of the breast, whereas most express estrogen receptors.

  5. MODELING OF TUBULAR ELECTROCHEMICAL REACTOR FOR DYE REMOVAL

    Directory of Open Access Journals (Sweden)

    V. VIJAYAKUMAR

    2017-06-01

    Full Text Available The aim of the present investigation is to model a tubular electrochemical reactor for the treatment of synthetic dye wastewater. The tubular reactor was modeled and solved by finite difference method. For the model solution, the column was divided into 11 nodes in the axial direction and the variation in the radial direction has been neglected. An initial dye concentration of 200 mg L-1was taken in the reservoir. The reactor was operated in a batch with recirculation operation. Based on preliminary experiments all parameters have been optimized. The model simulation is compared with the experimental value and it is observed that the model fairly matches well with the experiment. The modeling of tubular electrochemical reactors for dye waste water treatment could be useful in the design and scale up of electrochemical process.

  6. Development of 12.5 m² Solar Collector Panel for Solar Heating Plants

    DEFF Research Database (Denmark)

    Vejen, Niels Kristian; Furbo, Simon; Shah, Louise Jivan

    2004-01-01

    and large solar heating systems. Based on the theoretical findings a prototype of an improved HT solar collector was built and tested side-by-side with the original HT solar collector. The improved HT collector makes use of a changed insulation material, an absorber with improved absorptance and emittance......Theoretical and experimental investigations have elucidated how different changes in the design of the 12.5 m(2) HT flat-plate solar collector from the Danish company ARCON Solvarme A/S influence the solar collector efficiency and the yearly thermal performance. The collector is designed for medium...

  7. Evaluation of initial collector field performance at the Langley Solar Building Test Facility

    Science.gov (United States)

    Boyle, R. J.; Knoll, R. H.; Jensen, R. N.

    1977-01-01

    The thermal performance of the solar collector field for the NASA Langley Solar Building Test Facility is given for October 1976 through January 1977. An 1180 square meter solar collector field with seven collector designs helped to provide hot water for the building heating system and absorption air conditioner. The collectors were arranged in 12 rows with nominally 51 collectors per row. Heat transfer rates for each row are calculated and recorded along with sensor, insolation, and weather data every 5 minutes using a mini-computer. The agreement between the experimental and predicted collector efficiencies was generally within five percentage points.

  8. Prototype Tsunami Evacuation Park in Padang, West Sumatra, Indonesia

    Science.gov (United States)

    Tucker, B. E.; Cedillos, V.; Deierlein, G.; Di Mauro, M.; Kornberg, K.

    2012-12-01

    Padang, Indonesia, a city of some 900,000 people, half of whom live close to the coast and within a five-meter elevation above sea level, has one of the highest tsunami risks in the world due to its close offshore thrust-fault seismic hazard, flat terrain and dense population. There is a high probability that a tsunami will strike the shores of Padang, flooding half of the area of the city, within the next 30 years. If that tsunami occurred today, it is estimated that several hundred thousand people would die, as they could not reach safe ground in the ~30 minute interval between the earthquake's occurrence and the tsunami's arrival. Padang's needs have been amply demonstrated: after earthquakes in 2007, 2009, 2011 and 2012, citizens, thinking that those earthquakes might cause a tsunami, tried to evacuate in cars and motorbikes, which created traffic jams, and most could not reach safe ground in 30 minutes. Since 2008, GeoHazards International (GHI) and Stanford University have studied a range of options for improving this situation, including ways to accelerate evacuation to high ground with pedestrian bridges and widened roads, and means of "vertical" evacuation in multi-story buildings, mosques, pedestrian overpasses, and Tsunami Evacuation Parks (TEPs), which are man-made hills with recreation facilities on top. TEPs proved most practical and cost-effective for Padang, given the available budget, technology and time. The Earth Observatory Singapore (EOS) developed an agent-based model that simulates pedestrian and vehicular evacuation to assess tsunami risk and risk reduction interventions in Southeast Asia. EOS applied this model to analyze the effectiveness in Padang of TEPs over other tsunami risk management approaches in terms of evacuation times and the number of people saved. The model shows that only ~24,000 people (20% of the total population) in the northern part of Padang can reach safe ground within 30 minutes, if people evacuate using cars and

  9. Who evacuates when hurricanes approach? The role of risk, information, and location.

    Science.gov (United States)

    Stein, Robert M; Dueñas-Osorio, Leonardo; Subramanian, Devika

    2010-01-01

    This article offers an expanded perspective on evacuation decision making during severe weather. In particular, this work focuses on uncovering determinants of individual evacuation decisions. We draw on a survey conducted in 2005 of residents in the eight-county Houston metropolitan area after Hurricane Rita made landfall on September 24, 2005. We find that evacuation decisions are influenced by a heterogeneous set of parameters, including perceived risk from wind, influence of media and neighbors, and awareness of evacuation zone, that are often at variance with one of the primary measures of risk used by public officials to order or recommend an evacuation (i.e., storm surge). We further find that perceived risk and its influence on evacuation behavior is a local phenomenon more readily communicated by and among individuals who share the same geography, as is the case with residents living inside and outside official risk areas. Who evacuates and why is partially dependent on where one lives because perceptions of risk are not uniformly shared across the area threatened by an approaching hurricane and the same sources and content of information do not have the same effect on evacuation behavior. Hence, efforts to persuade residential populations about risk and when, where, and how to evacuate or shelter in place should originate in the neighborhood rather than emanating from blanket statements from the media or public officials. Our findings also raise important policy questions (included in the discussion section) that require further study and consideration by those responsible with organizing and implementing evacuation plans.

  10. Rapid health assessments of evacuation centres in areas affected by Typhoon Haiyan

    Directory of Open Access Journals (Sweden)

    Ruth Alma Ramos

    2015-11-01

    Full Text Available Introduction: Typhoon Haiyan caused thousands of deaths and catastrophic destruction, leaving many homeless in Region 8 of the Philippines. A team from the Philippine Field Epidemiology Training Program conducted a rapid health assessment survey of evacuation centres severely affected by Haiyan. Methods: A descriptive study was conducted whereby a convenience sample of evacuation centres were assessed on the number of toilets per evacuee, sanitation, drinking-water, food supply source and medical services. Results: Of the 20 evacuation centres assessed, none had a designated manager. Most were located in schools (70% with the estimated number of evacuees ranging from 15 to 5000 per centre. Only four (20% met the World Health Organization standard for number of toilets per evacuee; none of the large evacuation centres had even half the recommended number of toilets. All of the evacuation centres had available drinking-water. None of the evacuation centres had garbage collection, vector control activities or standby medical teams. Fourteen (70% evacuation centres had onsite vaccination activities for measles, tetanus and polio virus. Many evacuation centres were overcrowded. Conclusion: Evacuation centres are needed in almost every disaster. They should be safely located and equipped with the required amenities. In disaster-prone areas such as the Philippines, schools and community centres should not be designated as evacuation centres unless they are equipped with adequate sanitation services.

  11. Absorber Alignment Measurement Tool for Solar Parabolic Trough Collectors: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Stynes, J. K.; Ihas, B.

    2012-04-01

    As we pursue efforts to lower the capital and installation costs of parabolic trough solar collectors, it is essential to maintain high optical performance. While there are many optical tools available to measure the reflector slope errors of parabolic trough solar collectors, there are few tools to measure the absorber alignment. A new method is presented here to measure the absorber alignment in two dimensions to within 0.5 cm. The absorber alignment is measured using a digital camera and four photogrammetric targets. Physical contact with the receiver absorber or glass is not necessary. The alignment of the absorber is measured along its full length so that sagging of the absorber can be quantified with this technique. The resulting absorber alignment measurement provides critical information required to accurately determine the intercept factor of a collector.

  12. Solar water disinfecting system using compound parabolic concentrating collector

    Energy Technology Data Exchange (ETDEWEB)

    El-Ghetany, H.H.; Saitoh, T.S. [Tohoku Univ., Sendai (Japan)

    2000-05-31

    Solar water disinfection is an alternative technology using solar radiation and thermal treatment to inactivate and destroy pathogenic microorganisms present in water. The Compound Parabolic Concentrating, (CPC) collector can be used as an efficient key component for solar disinfectanting system. Two types of the CPC collectors are studied, namely the transparent-tube and the Copper-tube CPC collector. It is found that after 30 minutes of exposing the water sample to solar radiation or heating it up to 65 degree C for a few minuets all the coliform bacterial present in the contaminated water sample were completely eliminated. In this article, the effect of water temperature on the disinfecting process was presented. Thermal and micro-biological measurements were also made to evaluate the system performance. (author)

  13. Four Interstellar Dust Candidates from the Stardust Interstellar Dust Collector

    Science.gov (United States)

    Westphal, A. J.; Allen, C.; Bajt, S.; Bechtel, H. A.; Borg, J.; Brenker, F.; Bridges, J.; Brownlee, D. E.; Burchell, M.; Burghammer, M.; hide

    2011-01-01

    In January 2006, the Stardust sample return capsule returned to Earth bearing the first solid samples from a primitive solar system body, Comet 81P/Wild2, and a collector dedicated to the capture and return of contemporary interstellar dust. Both collectors were approx. 0.1 sq m in area and were composed of aerogel tiles (85% of the collecting area) and aluminum foils. The Stardust Interstellar Dust Collector (SIDC) was exposed to the interstellar dust stream for a total exposure factor of 20 sq m/day. The Stardust Interstellar Preliminary Examination (ISPE) is a consortium-based project to characterize the collection using nondestructive techniques. The goals and restrictions of the ISPE are described . A summary of analytical techniques is described.

  14. Optical losses due to tracking on solar thermal collectors

    DEFF Research Database (Denmark)

    Sallaberry, Fabienne; Pujol-Nadal, Ramn; Peres, Bengt

    2017-01-01

    For a wide range of operational temperatures, the solar thermal collectors can use optical concentration systems to optimize their efficiency. However, as optical concentration relies on direct solar radiation, it is necessary to use a solar tracker following the sun direction to maximize...... the amount of useful solar radiation received. The selection of the appropriate tracking systems matching the optical concentration factor is essential to achieve optimal collector efficiency. Otherwise, the concentrator would experience high optical losses due to the inadequate focusing of the direct solar...... radiation onto its receiver, regardless of its quality. This paper gives the state-of-the-art of the methodologies available to characterize the tracking error of a concentrating collector, a summary of different previous studies done in this subject and of the standardization regarding the tracking...

  15. Low cost bare-plate solar air collector

    Science.gov (United States)

    Maag, W. L.; Wenzler, C. J.; Rom, F. E.; Vanarsdale, D. R.

    1980-09-01

    A low cost, bare plate solar collector for preheating ambient air was developed. This type of solar heating system would be applicable for preheating ventilation air for public buildings or other commercial and industrial ventilation requirements. Two prototype collectors were designed, fabricated and installed into an instrumented test system. Tests were conducted for a period of five months. Results of the tests showed consistent operating efficiencies of 60 percent or greater with air preheat temperature uses up to 20 degrees for one of the prototypes. The economic analyses indicated that this type of solar system was economically viable. For the materials of construction and the type of fabrication and installation perceived, costs for the bare plate solar collector are attainable. Applications for preheating ventilation air for schools were evaluated and judged to be economically viable.

  16. Liquid metal current collectors for high-speed rotating machinery

    International Nuclear Information System (INIS)

    Carr, S.L.

    1976-01-01

    Recent interest in superconducting motors and generators has created a renewed interest in homopolar machinery. Homopolar machine designs have always been limited by the need for compact, high-current, low-voltage, sliding electrical curent collectors. Conventional graphite-based solid brushes are inadequate for use in homopolar machines. Liquid metals, under certain conditions of relative sliding velocities, electrical currents, and magnetic fields are known to be capable of performing well in homopolar machines. An effort to explore the capabilities and limits of a tongue-and-groove style current collector, utilizing sodium-potassium eutectic alloy (NaK) as the working fluid in high sliding speed operation is reported here. A double current collector generator model with a 14.5-cm maximum rotor diameter, 20,000 rpm rotational capability, and electrical current carrying ability was constructed and operated successfully at a peripheral velocity of 125 m/s. The limiting factor in these experiments was a high-speed fluid-flow instability resulting in the ejection of the working fluid from the operating portions of the collectors. The effects of collector size and geometry, working fluid (NaK or water), and cover gas pressure are reported. Hydrodynamic frictional torque-speed curves are given for the two fluids and for several geometries. Electrical resistances as a function of peripheral velocity at 60 amperes are reported, and the phenomenology of the high-speed fluid-flow instabilities is discussed. The possibility of long-term high-speed operation of current collectors of the tongue-and-groove type, along with experimental and theoretical hydrodynamic friction losses at high peripheral velocities, is considered

  17. On the Adsorption of Some Anionic Collectors on Fluoride Minerals

    DEFF Research Database (Denmark)

    Sørensen, Emil

    1973-01-01

    Test flotations have been carried out in a small apparatus under standardized conditions in order to determine the dependence of the flotation yield on the reagent concentration for certain minerals and anionic collectors. The results suggest that a special adsorption mechanism is operating...... in the case of fluoride minerals, and a theory is presented which involves the joint action of ionic and hydrogen bonds. A precondition is the compatibility of the crystal geometry with the configuration of the polar group of the collector molecules....

  18. Studies of impurity recycling by the collector probe technique

    International Nuclear Information System (INIS)

    Hildebrandt, D.; Grote, H.; Herrmann, A.; Laux, M.; Pech, P.; Reiner, H.D.; Wolff, H.

    1987-01-01

    In order to study recycling effects of the nonintrinsic impurity Li discharges with and without LiD-pellet injection were investigated. The observed maximum impurity level of Li in the SOL plasma of discharges without injection reaches less than 10% of that observed in discharges with injection. The measurements offer the possibility to distinguish between influxes from the wall and those which reach the collector probe via the core plasma. The time evolution, orientation and radial dependence of the impurity fluxes are characteristic features of their origin. The consideration of all these features facilitates a better understanding of collector probe measurements in the SOL-plasma. (orig.)

  19. Opensource Software for MLR-Modelling of Solar Collectors

    DEFF Research Database (Denmark)

    Bacher, Peder; Perers, Bengt

    2011-01-01

    A first research version is now in operation of a software package for multiple linear regression (MLR) modeling and analysis of solar collectors according to ideas originating all the way from Walletun et. al. (1986), Perers, (1987 and 1993). The tool has been implemented in the free and open...... source program R http://www.r-project.org/. Applications of the software package includes: visual validation, resampling and conversion of data, collector performance testing analysis according to the European Standard EN 12975 (Fischer et al., 2004), statistical validation of results...

  20. Tracking local control of a parabolic trough collector

    International Nuclear Information System (INIS)

    Ajona, J.I.; Alberdi, J.; Gamero, E.; Blanco, J.

    1992-01-01

    In the local control, the sun position related to the trough collector is measured by two photo-resistors. The provided electronic signal is then compared with reference levels in order to get a set of B logical signals which form a byte. This byte and the commands issued by a programmable controller are connected to the inputs of o P.R.O.M. memory which is programmed with the logical equations of the control system. The memory output lines give the control command of the parabolic trough collector motor. (Author)