Sample records for project cooling tower

  1. Cooling tower waste reduction

    Coleman, S.J.; Celeste, J.; Chine, R.; Scott, C.


    At Lawrence Livermore National Laboratory (LLNL), the two main cooling tower systems (central and northwest) were upgraded during the summer of 1997 to reduce the generation of hazardous waste. In 1996, these two tower systems generated approximately 135,400 lbs (61,400 kg) of hazardous sludge, which is more than 90 percent of the hazardous waste for the site annually. At both, wet decks (cascade reservoirs) were covered to block sunlight. Covering the cascade reservoirs reduced the amount of chemical conditioners (e.g. algaecide and biocide), required and in turn the amount of waste generated was reduced. Additionally, at the northwest cooling tower system, a sand filtration system was installed to allow cyclical filtering and backflushing, and new pumps, piping, and spray nozzles were installed to increase agitation. the appurtenance upgrade increased the efficiency of the cooling towers. The sand filtration system at the northwest cooling tower system enables operators to continuously maintain the cooling tower water quality without taking the towers out of service. Operational costs (including waste handling and disposal) and maintenance activities are compared for the cooling towers before and after upgrades. Additionally, the effectiveness of the sand filter system in conjunction with the wet deck covers (northwest cooling tower system), versus the cascade reservoir covers alone (south cooling tower south) is discussed. the overall expected return on investment is calculated to be in excess of 250 percent. this upgrade has been incorporated into the 1998 DOE complex-wide water conservation project being led by Sandia National Laboratory/Albuquerque.

  2. Overview of the Chalk Point Cooling Tower Project, 1972-1979

    Moon, M.L. (ed.)


    The objectives, methodologies, data, and analytical results of the Chalk Point Cooling Tower Program are reviewed. The overview intergrates the concepts and activities of the various program elements to provide a coherent view of the program in its entirety. Samples of the various data acquired are included together with very brief summaries of the conclusions. The report is extensively referenced to provide specific directions to the more extensive treatments of the program, data tabulations, and tape libraries available in the complete library of Chalk Point reports. The Chalk Point data is a resource for the study of cooling tower salt deposition processes and impacts in general. The methods used, while developed to facilitate the assessment of salt drift impact at Chalk Point, also have applicability to cooling tower impact analysis at other sites.

  3. Cooling towers principles and practice

    Hill, G B; Osborn, Peter D


    Cooling Towers: Principles and Practice, Third Edition, aims to provide the reader with a better understanding of the theory and practice, so that installations are correctly designed and operated. As with all branches of engineering, new technology calls for a level of technical knowledge which becomes progressively higher; this new edition seeks to ensure that the principles and practice of cooling towers are set against a background of up-to-date technology. The book is organized into three sections. Section A on cooling tower practice covers topics such as the design and operation of c

  4. Ozone Treatment For Cooling Towers

    Blackwelder, Rick; Baldwin, Leroy V.; Feeney, Ellen S.


    Report presents results of study of cooling tower in which water treated with ozone instead of usual chemical agents. Bacteria and scale reduced without pollution and at low cost. Operating and maintenance costs with treatment about 30 percent of those of treatment by other chemicals. Corrosion rates no greater than with other chemicals. Advantage of ozone, even though poisonous, quickly detected by smell in very low concentrations.

  5. 2004 Savannah River Cooling Tower Collection (U)

    Garrett, Alfred [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Parker, Matthew J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Villa-Aleman, E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)


    The Savannah River National Laboratory (SRNL) collected ground truth in and around the Savannah River Site (SRS) F-Area cooling tower during the spring and summer of 2004. The ground truth data consisted of air temperatures and humidity inside and around the cooling tower, wind speed and direction, cooling water temperatures entering; inside adn leaving the cooling tower, cooling tower fan exhaust velocities and thermal images taken from helicopters. The F-Area cooling tower had six cells, some of which were operated with fans off during long periods of the collection. The operating status (fan on or off) for each of the six cells was derived from operations logbooks and added to the collection database. SRNL collected the F-Area cooling tower data to produce a database suitable for validation of a cooling tower model used by one of SRNL's customer agencies. SRNL considers the data to be accurate enough for use in a model validation effort. Also, the thermal images of the cooling tower decks and throats combined with the temperature measurements inside the tower provide valuable information about the appearance of cooling towers as a function of fan operating status and time of day.

  6. Solar tower enhanced natural draft dry cooling tower

    Yang, Huiqiang; Xu, Yan; Acosta-Iborra, Alberto; Santana, Domingo


    Concentrating Solar Power (CSP) plants are located in desert areas where the Direct Normal Irradiance (DNI) value is very high. Since water resource is scarcely available, mechanical draft cooing technology is commonly used, with power consumption of mechanical fans being approximately 2% of the total power generated. Today, there is only one solar power plant (Khi Solar One in South Africa) uses a condenser installed in a Natural Draft Cooling (NDC) tower that avoids the windage loss of water occurring in wet cooling towers. Although, Khi Solar One is a cavity receiver power tower, the receivers can be hung onto the NDC tower. This paper looks at a novel integration of a NDC tower into an external molten salt receiver of a solar power plant, which is one of a largest commercial molten salt tower in China, with 100MWe power capacity. In this configuration study, the NDC tower surrounds the concrete tower of the receiver concentrically. In this way, the receiver concrete tower is the central support of the NDC tower, which consists of cable networks that are fixed to the concrete tower and suspended at a certain height over the floor. The cable networks support the shell of the NDC tower. To perform a preliminary analysis of the behavior of this novel configuration, two cases of numerical simulation in three dimensional (3D) models have been solved using the commercial Computational Fluid Dynamics (CFD) code, ANSYS Fluent 6.3. The results show that the integration of the NDC tower into an external central receiver tower is feasible. Additionally, the total heat transfer rate is not reduced but slightly increases when the molten salt receiver is in operation because of the additional natural draft induced by the high temperature of the receiver.

  7. Fire behaviour of cooling tower packing; Brandverhalten von Kuehlturmeinbauten

    Mattausch, Tim [DMT GmbH und Co. KG, Dortmund (Germany). Fachstelle fuer Brandschutz


    The rapid burning down of the cooling tower of the shutdown power plant in Schwandorf revealed the potential of a total loss of a cooling tower in case of fire. VGB ordered a research project in order to obtain more knowledge about the fire risk of cooling tower packing currently applied. Depending on kind and age of the plastics used, the results of these tests manifest a big variation of the fire behaviour. For the applications of plastics, it is essential to determine and to adhere to organisational fire protection measures. (orig.)

  8. Statistics Analysis Measures Painting of Cooling Tower

    A. Zacharopoulou


    Full Text Available This study refers to the cooling tower of Megalopolis (construction 1975 and protection from corrosive environment. The maintenance of the cooling tower took place in 2008. The cooling tower was badly damaged from corrosion of reinforcement. The parabolic cooling towers (factory of electrical power are a typical example of construction, which has a special aggressive environment. The protection of cooling towers is usually achieved through organic coatings. Because of the different environmental impacts on the internal and external side of the cooling tower, a different system of paint application is required. The present study refers to the damages caused by corrosion process. The corrosive environments, the application of this painting, the quality control process, the measures and statistics analysis, and the results were discussed in this study. In the process of quality control the following measurements were taken into consideration: (1 examination of the adhesion with the cross-cut test, (2 examination of the film thickness, and (3 controlling of the pull-off resistance for concrete substrates and paintings. Finally, this study refers to the correlations of measurements, analysis of failures in relation to the quality of repair, and rehabilitation of the cooling tower. Also this study made a first attempt to apply the specific corrosion inhibitors in such a large structure.

  9. Asbestos in cooling-tower waters

    Lewis, B.A.G.


    Fill material in natural- or mechanical-draft cooling towers can be manufactured from a variety of materials, including asbestos cement or asbestos paper. To aid in the environmental impact assessment of cooling towers containing these asbestos types of fill, information on these materials was obtained from cooling-tower vendors and users. Samples of makeup, basin, and blowdown waters at a number of operating cooling towers were obtained, and identification and enumeration of asbestos in the samples were performed by transmission electron microscopy, selected-area electron diffraction, and energy-dispersive x-ray analysis. Asbestos fibers were detected in cooling-tower water at 10 of the 18 sites sampled in the study. At all but three sites, the fibers were detected in cooling-tower basin or blowdown samples, with no fibers detected in the makeup water. The fibers were identified as chrysotile at all sites except one. Concentrations were on the order of 10/sup 6/ to 10/sup 8/ fibers/liter of water, with mass concentrations between <0.1 to 37 The maximum concentrations of asbestos fibers in air near ground due to drift from cooling towers were estimated (using models) to be on the order of asbestos concentrations reported for ambient air up to distances of 4 km downwind of the towers. The human health hazard due to abestos in drinking-water supplies is not clear. Based on current information, the concentrations of asbestos in natural waters after mixing with cooling-tower blowdown containing 10/sup 6/ to 10/sup 8/ fibers/liter will pose little health risk. These conclusions may need to be revised if future epidemiological studies so indicate.

  10. Simple model of a cooling tower plume

    Jan, Cizek; Jiri, Nozicka


    This article discusses the possibilities in the area of modeling of the so called cooling tower plume emergent at operating evaporating cooling systems. As opposed to recent publication, this text focuses on the possibilities of a simplified analytic description of the whole problem where this description shall - in the future - form the base of a calculation algorithms enabling to simulate the efficiency of systems reducing this cooling tower plume. The procedure is based on the application of basic formula for the calculation of the velocity and concentration fields in the area above the cooling tower. These calculation is then used to determine the form and the total volume of the plume. Although this approach does not offer more exact results, it can provide a basic understanding of the impact of individual quantities relating to this problem.

  11. Dry cooling tower with water augmentation

    Ireland, R.G.; Tramontini, V.N.


    An air cooling tower system is disclosed for condensing exhaust steam in power plants, that has water cooling augmentation to maintain the plant cooling capacity during high atmospheric temperature periods. The cooling tower includes a plurality of banks of brazed aluminum plate and fin type heat exchangers arranged in inverted ''v'' shaped sets. These heat exchangers cool ammonia used as the cooling fluid in the primary condenser for the power plant turbine exhaust steam. Each of these heat exchangers has a core consisting of a plurality of parallel aluminum plates spaced apart by fin assemblies that define a plurality of fluid passes. Approximately every other one of these passes has closed sides that open at the ends of the core to headers and define ammonia passes. The passes adjacent the ammonia passes are open at the sides and define air passes that permit the free flow of air transversely through the heat exchanger cores. An additional pass is provided adjacent every fourth one of the ammonia passes and these have closed sides and ends and define the passes for the cooling water. The water passes communicate at the bottom of the core with a water inlet manifold and at the top of the core with a water outlet manifold. The cooling tower system is designed so that at 55 degrees fahrenheit air temperatures or below, the cooling air alone will provide the necessary cooling for the ammonia to satisfy plant requirements. Above 55 degrees fahrenheit air temperature, cooling water from a separate water tank is pumped through the water passes to provide an additional cooling effect to maintain the design cooling capacity.

  12. Numerical research of a super-large cooling tower subjected to accidental loads

    Li, Yi; Lin, Feng [Department of Building Engineering, Tongji University, Shanghai 200092 (China); Gu, Xianglin, E-mail: [Department of Building Engineering, Tongji University, Shanghai 200092 (China); Lu, Xiaoqin [Guangdong Electric Power Design Institute, Guangzhou 510660 (China)


    With the continued development of nuclear power plants, more and more super-large cooling towers are to be built in China and around the world. For the safe operation of nuclear power plants, research work has been done on the causes of collapse of cooling towers, collapse modes and the secondary disasters caused by the collapse of cooling towers. However, the collapse modes and the ground vibration induced by the collapse of cooling towers subjected to the accidental loads have not been fully understood. This paper has been focused on the modes and mechanisms behavior of the collapse of cooling towers subjected to accidental loads. Meanwhile, prediction of the ground vibration due to the collapse of the cooling towers has also been completed in a parallel project. Using dynamic finite element program LS-DYNA, a 3D finite element model for a super-large cooling tower was developed and the nonlinear material models were incorporated. In this paper, four types of accidental loads were considered to trigger the collapse or local failure of the tower, including vehicle collision, airplane impact, local explosion and missile attack. It was found that vehicle collision, missile attack and small TNT equivalent explosives (2 kg, 20 kg, 200 kg) might result in local failure of the cooling tower, however, the tower can still keep stable. On the other hand, large TNT equivalent explosives (2000 kg, 4500 kg) could cause severe damages in the inclined columns of the cooling tower, and lead to progressive collapse of the entire cooling tower. The two kinds of TNT equivalent explosives caused the same collapse mode while the collapsing duration was different. The airplane impacted at the throat of the cooling tower caused the local failure of shell structure of the tower, and then the progressive collapse of the cooling tower happened due to the gravitational action. The resulting collapse mode was different from that triggered by the local explosion.

  13. Tautological Classes on Projective Towers

    Negut, Andrei


    When one has a tower of projective bundles over an algebraic variety and wishes to compute the push-forward of any cohomology class down this tower, one needs to recursively compute the Segre classes corresponding to each level. In this paper, we give a closed combinatorial formula that encodes this recursive procedure.


    Lee, S; Alfred Garrett, A; James02 Bollinger, J; Larry Koffman, L


    Industrial processes use mechanical draft cooling towers (MDCT's) to dissipate waste heat by transferring heat from water to air via evaporative cooling, which causes air humidification. The Savannah River Site (SRS) has cross-flow and counter-current MDCT's consisting of four independent compartments called cells. Each cell has its own fan to help maximize heat transfer between ambient air and circulated water. The primary objective of the work is to simulate the cooling tower performance for the counter-current cooling tower and to conduct a parametric study under different fan speeds and ambient air conditions. The Savannah River National Laboratory (SRNL) developed a computational fluid dynamics (CFD) model and performed the benchmarking analysis against the integral measurement results to accomplish the objective. The model uses three-dimensional steady-state momentum, continuity equations, air-vapor species balance equation, and two-equation turbulence as the basic governing equations. It was assumed that vapor phase is always transported by the continuous air phase with no slip velocity. In this case, water droplet component was considered as discrete phase for the interfacial heat and mass transfer via Lagrangian approach. Thus, the air-vapor mixture model with discrete water droplet phase is used for the analysis. A series of parametric calculations was performed to investigate the impact of wind speeds and ambient conditions on the thermal performance of the cooling tower when fans were operating and when they were turned off. The model was also benchmarked against the literature data and the SRS integral test results for key parameters such as air temperature and humidity at the tower exit and water temperature for given ambient conditions. Detailed results will be published here.

  15. European dry cooling tower operating experience

    DeSteese, J.G.; Simhan, K.


    Interviews were held with representatives of major plants and equipment manufacturers to obtain current information on operating experience with dry cooling towers in Europe. The report documents the objectives, background, and organizational details of the study, and presents an itemized account of contacts made to obtain information. Plant selection was based on a merit index involving thermal capacity and length of service. A questionnaire was used to organize operational data, when available, into nine major categories of experience. Information was also solicited concerning the use of codes and standards to ensure the achievement of cooling tower performance. Several plant operators provided finned-tube samples for metallographic analysis. Additionally, information on both operating experience and developing technology was supplied by European technical societies and research establishments. Information obtained from these contacts provides an updated and representative sample of European experience with dry cooling towers, which supplements some of the detailed reviews already available in the literature. In addition, the study presents categorized operating experience with installations which have not been reviewed so extensively, but nevertheless, have significant operational histories when ranked by the merit index. The contacts and interviews reported in the survey occurred between late March and October 1975. The study was motivated by the expressed interest of U.S. utility industry representatives who expect European experience to provide a basis of confidence that dry cooling is a reliable technology, applicable when necessary, to U.S. operating requirements.

  16. Technical Evaluation of Side Stream Filtration for Cooling Towers



    Cooling towers are an integral component of many refrigeration systems, providing comfort or process cooling across a broad range of applications. Cooling towers represent the point in a cooling system where heat is dissipated to the atmosphere through evaporation. Cooling towers are commonly used in industrial applications and in large commercial buildings to release waste heat extracted from a process or building system through evaporation of water.

  17. Disaster Management for Cooling Tower- Case Study.

    1Deshmukh Azhar A


    Full Text Available Cooling towers are prone to numerous disasters that can arise naturally or through human intervention. The safety of cooling towers becomes utmost importance for the plants to function properly. The study focused on identification of various disasters and the risks associated with them. The disasters can be earthquake, volcanoes, storm, extreme temperature, fire incident, terror attack, hazardous material leakage etc. The impact and vulnerability analysis of these disasters is conducted to find the associated risks properly. Mitigating risks is as important as identifying them. The two most important risks identified are Design Risk and Bacterial Risk. The preparedness to these risks helps in mitigating them. A probabilistic catastrophic risk model has been identified which performs a cost benefit analysis for mitigating the risks

  18. Side Stream Filtration for Cooling Towers



    This technology evaluation assesses side stream filtration options for cooling towers, with an objective to assess key attributes that optimize energy and water savings along with providing information on specific technology and implementation options. This information can be used to assist Federal sites to determine which options may be most appropriate for their applications. This evaluation provides an overview of the characterization of side stream filtration technology, describes typical applications, and details specific types of filtration technology.

  19. Knowledge base for the systematic design of wet cooling towers. Pt. 1: Selection and tower characteristics

    Mohiuddin, A.K.M. [Bangladesh Inst. of Technology, Dhaka (Bangladesh). Dept. of Mechanical Engineering; Kant, K. [Indian Inst. of Tech., Kanpur (India). Dept. of Mechanical Engineering and Nuclear Centre


    This paper describes part of the detailed methodology for the thermal design of wet, counterflow and crossflow types of mechanical and natural draught cooling towers. Starting with a brief introduction, an attempt is made here to present different steps of cooling tower design. The steps include: selection of a cooling tower determination of tower characteristic ratio; computation of moist air properties; determination of the ratio of the water-to-air loading; integration procedure for the tower characteristic ratio. The design of a cooling tower needs the use of different logical decisions, empirical relations and assumptions. The choice of a proper tower and its proper design would increase its efficiency and help conserve energy. (author)

  20. Counter-Flow Cooling Tower Test Cell

    Dvořák Lukáš


    Full Text Available The article contains a design of a functional experimental model of a cross-flow mechanical draft cooling tower and the results and outcomes of measurements. This device is primarily used for measuring performance characteristics of cooling fills, but with a simple rebuild, it can be used for measuring other thermodynamic processes that take part in so-called wet cooling. The main advantages of the particular test cell lie in the accuracy, size, and the possibility of changing the water distribution level. This feature is very useful for measurements of fills of different heights without the influence of the spray and rain zone. The functionality of this test cell has been verified experimentally during assembly, and data from the measurement of common film cooling fills have been compared against the results taken from another experimental line. For the purpose of evaluating the data gathered, computational scripts were created in the MATLAB numerical computing environment. The first script is for exact calculation of the thermal balance of the model, and the second is for determining Merkel’s number via Chebyshev’s method.

  1. Use of nanofiltration to reduce cooling tower water usage.

    Sanchez, Andres L.; Everett, Randy L.; Jensen, Richard Pearson; Cappelle, Malynda A.; Altman, Susan Jeanne


    Nanofiltration (NF) can effectively treat cooling-tower water to reduce water consumption and maximize water usage efficiency of thermoelectric power plants. A pilot is being run to verify theoretical calculations. A side stream of water from a 900 gpm cooling tower is being treated by NF with the permeate returning to the cooling tower and the concentrate being discharged. The membrane efficiency is as high as over 50%. Salt rejection ranges from 77-97% with higher rejection for divalent ions. The pilot has demonstrated a reduction of makeup water of almost 20% and a reduction of discharge of over 50%.

  2. Use of nanofiltration to reduce cooling tower water consumption.

    Altman, Susan Jeanne; Ciferno, Jared


    Nanofiltration (NF) can effectively treat cooling-tower water to reduce water consumption and maximize water usage efficiency of thermoelectric power plants. A pilot is being run to verify theoretical calculations. A side stream of water from a 900 gpm cooling tower is being treated by NF with the permeate returning to the cooling tower and the concentrate being discharged. The membrane efficiency is as high as over 50%. Salt rejection ranges from 77-97% with higher rejection for divalent ions. The pilot has demonstrated a reduction of makeup water of almost 20% and a reduction of discharge of over 50%.

  3. Strategy for the Operation of Cooling Towers with variable Speed Fans

    Iñigo-Golfín, J


    Within the SPS Cooling Water Project at CERN aimed at the reduction of water consumption, this primary open cooling loop will be closed and all the primary cooling circuit components will be upgraded to the new required duty and brought to the necessary safety and operability standards. In particular the tower fans will be fitted with variable frequency drives to replace the existing two speed motors. This paper presents a study to optimize the operation of SPS cooling towers taking into account outdoor conditions (wet and dry bulb temperatures) and the entirety of the primary circuit in which they will operate.

  4. Environmental Impacts from the Operation of Cooling Towers at SRP

    Smith, F.G. III


    An assessment has been made of the environmental effects that would occur from the operation of cooling towers at the SRP reactors. A more realistic numerical model of the cooling tower plume has been used to reassess the environmental impacts. The following effects were considered: (1) the occurrence of fog and ice and their impact on nearby structures, (2) drift and salt deposition from the plume, (3) the length and height of the visible plume, and (4) the possible dose from tritium.

  5. 75 FR 63802 - Action Affecting Export Privileges; Parto Abgardan Cooling Towers Co.


    ... Bureau of Industry and Security Action Affecting Export Privileges; Parto Abgardan Cooling Towers Co. Parto Abgardan Cooling Towers Co., P.O. Box 966, Folsom, CA 95763; and P.O. Box 19395/5478, Tehran, Iran... Cooling Towers, Co. Applicable to Parto Abgardan Cooling Towers Co. Pursuant to Section 766.23 of the...

  6. Structural engineering developments in power plant cooling tower construction. 100 years of natural draught cooling towers - from tower cooler to cooling tower. Bautechnische Entwicklungen im Kraftwerkskuehlturmbau. 100 Jahre Naturzugkuehltuerme - vom Kaminkuehler zum Kuehlkamin

    Damjakob, H.; Depe, T.; Vrangos, V. (Balcke-Duerr AG, Ratingen (Germany))


    Almost exactly 100 years ago, tower-type structures were first used for the production of artificial ventilation for cooling purposes. The shell of these so-called tower coolers, today known as 'natural draught cooling towers', was, from the outset, the subject of multiple structural engineering develepments in respect of design, material, construction and statistical calculation. These developments have been stimulated especially by the spasmodic increase in dimensions in the application of power plant cooling towers and, more recently, in connection with ecological requirements. (orig.).

  7. High Flux Isotopes Reactor (HFIR) Cooling Towers Demolition Waste Management

    Pudelek, R. E.; Gilbert, W. C.


    This paper describes the results of a joint initiative between Oak Ridge National Laboratory, operated by UT-Battelle, and Bechtel Jacobs Company, LLC (BJC) to characterize, package, transport, treat, and dispose of demolition waste from the High Flux Isotope Reactor (HFIR), Cooling Tower. The demolition and removal of waste from the site was the first critical step in the planned HFIR beryllium reflector replacement outage scheduled. The outage was scheduled to last a maximum of six months. Demolition and removal of the waste was critical because a new tower was to be constructed over the old concrete water basin. A detailed sampling and analysis plan was developed to characterize the hazardous and radiological constituents of the components of the Cooling Tower. Analyses were performed for Resource Conservation and Recovery Act (RCRA) heavy metals and semi-volatile constituents as defined by 40 CFR 261 and radiological parameters including gross alpha, gross beta, gross gamma, alpha-emitting isotopes and beta-emitting isotopes. Analysis of metals and semi-volatile constituents indicated no exceedances of regulatory limits. Analysis of radionuclides identified uranium and thorium and associated daughters. In addition 60Co, 99Tc, 226Rm, and 228Rm were identified. Most of the tower materials were determined to be low level radioactive waste. A small quantity was determined not to be radioactive, or could be decontaminated. The tower was dismantled October 2000 to January 2001 using a detailed step-by-step process to aid waste segregation and container loading. The volume of waste as packaged for treatment was approximately 1982 cubic meters (70,000 cubic feet). This volume was comprised of plastic ({approx}47%), wood ({approx}38%) and asbestos transite ({approx}14%). The remaining {approx}1% consisted of the fire protection piping (contaminated with lead-based paint) and incidental metal from conduit, nails and braces/supports, and sludge from the basin. The waste

  8. Parametric study of closed wet cooling tower thermal performance

    Qasim, S. M.; Hayder, M. J.


    The present study involves experimental and theoretical analysis to evaluate the thermal performance of modified Closed Wet Cooling Tower (CWCT). The experimental study includes: design, manufacture and testing prototype of a modified counter flow forced draft CWCT. The modification based on addition packing to the conventional CWCT. A series of experiments was carried out at different operational parameters. In view of energy analysis, the thermal performance parameters of the tower are: cooling range, tower approach, cooling capacity, thermal efficiency, heat and mass transfer coefficients. The theoretical study included develops Artificial Neural Network (ANN) models to predicting various thermal performance parameters of the tower. Utilizing experimental data for training and testing, the models simulated by multi-layer back propagation algorithm for varying all operational parameters stated in experimental test.

  9. Energy and exergy analysis of counter flow wet cooling towers

    Saravanan Mani


    Full Text Available Cooling tower is an open system direct contact heat exchanger, where it cools water by both convection and evaporation. In this paper, a mathematical model based on heat and mass transfer principle is developed to find the outlet condition of water and air. The model is solved using iterative method. Energy and exergy analysis infers that inlet air wet bulb temperature is found to be the most important parameter than inlet water temperature and also variation in dead state properties does not affect the performance of wet cooling tower. .

  10. Legionella safety in cooling towers; Legionellaveiligheid in koeltorens

    Kordes, B. [Kordes Advies, (Netherlands); De Bok, F. [KBBL Wijhe, (Netherlands); De Zeeuw, L. [Holland Environment Group, (Netherlands); Settels, P. [Safety, Health Services and Ergonomics, ING, (Netherlands); Oesterholt, F.; Wullings, B. [KWR Watercycle Research Institute, (Netherlands); Guiot, P. [Tevan, Gorinchem (Netherlands); Brands, R. [Cumulus Nederland, Cuijk (Netherlands); Nuijten, O. [Kennisinstituut ISSO, Rotterdam (Netherlands); Wijne, R. [Beer advocaten, Amsterdam (Netherlands)


    In 9 articles attention is paid to several aspects with regard to Legionella in cooling towers: representative sampling, the use of copper and silver ionization or hydrogen peroxide to prevent Legionella growth and biofilms, the use of a zero-tolerance model to control a cooling tower installation, detection of DNA of Legionella Pneumophila, legionella safety in air conditioners, the model Legionella risk analysis and control of cooling tower installations, legislation and regulations for the control of cooling tower installations with regard to the Dutch Occupational Health and Safety Act ('Arbo-wet'), and an article about a lawsuit for victims of a Legionella outbreak, caused by careless owners of a cooling tower in Amsterdam, Netherlands. [Dutch] In 9 artikelen wordt in deze aflevering aandacht besteed aan verschillende aspecten m.b.t. Legionella in koeltorens: representatieve monstername, de toepassing van koper en zilver-ionisatie of waterstofperoxide om de groei van Legionella en biofilms te voorkomen, het gebruik van een zero-tolerance model om een koeltoren installatie te controleren, detectie van DNA van Legionella Pneumophila, Legionella veiligheid in luchtbehandelingsinstallaties, het model Legionella risicoanalyse en beheersplan voor koeltoreninstallaties, de rol van de Arbo-wet, en een artikel over een rechtszaak voor slachtoffers van Legionella door onzorgvuldig beheer van een koeltoren in Amsterdam.

  11. Free Cooling in the Water Cooling Towers: a Case Study for Istanbul, Turkey

    KOÇ, İbrahim; PARMAKSIZOGLU, Cem


    Energy saving in cooling towers which is used for cooling to the hot water can be significantly improved by using free cooling application. This application is commonly known economizer cycle and when outside conditions are suitable for cooling, it is used for. In this study, the free cooling is applied for the cold water necessity which is supplied by the chiller of the cooling tower in the factory which is available in Istanbul. The results show that the ...

  12. On synthesis and optimization of cooling water systems with multiple cooling towers

    Gololo, KV


    Full Text Available research on cooling water systems has focused mainly on heat exchanger network thus excluding the interaction between heat exchanger network and the cooling towers. This paper presents a technique for grassroot design of cooling water system for wastewater...

  13. Indiana State University Graduates to Advanced Plastic Cooling Towers

    Sullivan, Ed


    Perhaps more than many other industries, today's universities and colleges are beset by dramatically rising costs on every front. One of the areas where overhead can be contained or reduced is in the operation of the chilled water systems that support air conditioning throughout college campuses, specifically the cooling towers. Like many…

  14. Study of the comparative costs of five wet/dry cooling tower concepts

    Zaloudek, F.R.; Allemann, R.T.; Faletti, D.W.; Johnson, B.M.; Parry, H.L.; Smith, G.C.; Tokarz, R.D.; Walter, R.A.


    The projected cost of five alternative dry/wet power plant heat rejection concepts was studied under conditions imposed by hypothetical use in association with the San Juan Plant Unit 3, a 550-MWe facility currently under construction near the ''Four Corners'' area of New Mexico. The five alternative concepts were: integrated dry/wet tower; separate dry and wet towers; metal fin-tube induced draft tower with deluge water augmentation; plastic heat exchanger tower with deluge water augmentation, and metal fin-tube/deluge augmentation tower with an intermediate ammonia evaporation-condensation condenser and the cooling tower. The integrated dry/wet tower concept, already chosen for service at San Juan Unit 3, was included for reference purposes. All concepts were conceptually designed and estimated using the same bases and employing uniform practices. Each concept was assumed to use all water allocated for consumptive use in Unit 3. The cost estimates obtained showed the following descending order of ''comparable capital cost'': separate dry/wet; metal fin-tube/deluge; integrated dry/wet; plastic tube/deluge; and metal fin-tube/deluge/ammonia. The results indicate that two of the advanced concepts considered, i.e., the plastic tube/deluge concept and the metal fin tube/deluge/ammonia concept, can possibly reduce the overall costs of dry/wet cooling under conditions imposed by the site considered. It was recommended that these two concepts receive additional attention by the ERDA Dry Cooling Tower Program and industry to further quantify their potential benefits and demonstrate their performance and reliability.

  15. Towards Cooling Tower Efficiency-An Energy Audit Approach

    Long Su Weng Alwin


    Full Text Available This research studied the power generation trends from national grid and gas for a period of 4 years. Energy audit of critical systems like this is needful for optimal energy utilization. An energy audit was carried outon 6 industrial cooloing towers and their annual operating cost calculated. Variable speed drive suggested was installed and corresponding annual energy savings of 114,900 kWh/year cost saving of RM30,000 was achieved at a case study plant located in Malaysia. Cooling towers with smart systems was recommended for higher energy savings.

  16. Comparative study on thermal performance of natural draft cooling towers with finned shells

    Goodarzi, Mohsen [Bu-Ali Sina Univ., Hamedan (Iran, Islamic Republic of). Dept. of Mechanical Engineering


    The cooling efficiency of natural draft cooling towers under crosswind condition should be improved. In the present research work three different externally finned shells were considered for a typical natural draft cooling tower to investigate the cooling improvement. They were numerically simulated under normal and crosswind conditions. Numerical results show that twisting four fin plates over the tower shell along the 45 peripheral angle, could improve the cooling efficiency up to 6.5 %. Because of the periodic shape of the fin plates, the cooling efficiency of the cooling tower with finned shell is less sensitive to the change of wind.

  17. Short-term pilot cooling tower tests

    Suciu, D.F.; Miller, R.L.


    Two major problems are associated with the use of cooled geothermal water as coolant for the 5 MW(e) pilot plant at Raft River. They are: (1) a scaling potential owing to the chemical species present in solution, and (2) the corrosive nature of the geothermal water. Tests were conducted to obtain data so that methods can be devised to either reduce or eliminate effects from these problems. Data show that scaling can be prevented, but only by using a high concentration of dispersant. Pitting data, however, are not as conclusive and seem to indicate that pitting control cannot be realized, but this result cannot be substantiated without additional experimentation. Results also demonstrate that chromate can be removed by using either chemical destruction or ion exchange. Whichever method is used, EPA discharge limits for both chromate and zinc can be achieved. A preliminary economic analysis is presented.


    Lee, S; Alfred Garrett, A; James02 Bollinger, J; Larry Koffman, L


    Industrial processes use mechanical draft cooling towers (MDCT's) to dissipate waste heat by transferring heat from water to air via evaporative cooling, which causes air humidification. The Savannah River Site (SRS) has a MDCT consisting of four independent compartments called cells. Each cell has its own fan to help maximize heat transfer between ambient air and circulated water. The primary objective of the work is to conduct a parametric study for cooling tower performance under different fan speeds and ambient air conditions. The Savannah River National Laboratory (SRNL) developed a computational fluid dynamics (CFD) model to achieve the objective. The model uses three-dimensional steady-state momentum, continuity equations, air-vapor species balance equation, and two-equation turbulence as the basic governing equations. It was assumed that vapor phase is always transported by the continuous air phase with no slip velocity. In this case, water droplet component was considered as discrete phase for the interfacial heat and mass transfer via Lagrangian approach. Thus, the air-vapor mixture model with discrete water droplet phase is used for the analysis. A series of the modeling calculations was performed to investigate the impact of ambient and operating conditions on the thermal performance of the cooling tower when fans were operating and when they were turned off. The model was benchmarked against the literature data and the SRS test results for key parameters such as air temperature and humidity at the tower exit and water temperature for given ambient conditions. Detailed results will be presented here.

  19. Legionella control in power station cooling towers using oxidising biocides

    Sailer, Christian; Rawlinson, Julia; Killeen, Paul [Ecolab PTY LTD, Ascot, WA (Australia)


    Power stations have used oxidising biocides such as chlorine or bromine for many years to control microbial growth in their cooling towers. In this paper Ecolab trademark looks at the direct effect halogen concentration has on Legionella populations in order to determine the most effective halogenation rate required to ensure that the site key performance indicator (KPI) of < 100 colony-forming units (cfu) per mL can be maintained. (orig.)

  20. Operational cooling tower model (CTTOOL V1.0)

    Aleman, S. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); LocalDomainServers, L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Garrett, A. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)


    Mechanical draft cooling towers (MDCT’s) are widely used to remove waste heat from industrial processes, including suspected proliferators of weapons of mass destruction (WMD). The temperature of the air being exhausted from the MDCT is proportional to the amount of thermal energy being removed from the process cooling water, although ambient weather conditions and cooling water flow rate must be known or estimated to calculate the rate of thermal energy dissipation (Q). It is theoretically possible to derive MDCT air exhaust temperatures from thermal images taken from a remote sensor. A numerical model of a MDCT is required to translate the air exhaust temperature to a Q. This report describes the MDCT model developed by the Problem Centered Integrated Analysis (PCIA) program that was designed to perform those computational tasks. The PCIA program is a collaborative effort between the Savannah River National Laboratory (SRNL), the Northrop-Grumman Corporation (NG) and the Aerospace Corporation (AERO).

  1. Effects of biocidal treatments to inhibit the growth of legionellae and other microorganisms in cooling towers.

    Yamamoto, H; Ezaki, T; Ikedo, M; Yabuuchi, E


    The effects of biocidal treatments for cooling towers were examined through the use of chemicals and ultraviolet irradiation to inhibit the growth of legionellae and other microorganisms. In the water of cooling towers without continuous biocidal treatments, heterotrophic bacteria and bacterivorous protozoan first appeared, and then legionellae increased up to 10(4) CFU/100 ml. When a UV sterilizer was connected to the cooling tower, the legionellae count was 1/10 or 1/100 of that in the nontreated tower water. In the water of towers supplemented continuously with the biocidal chemicals, legionellae were not found during a 4-month period. The biocidal treatments tested were proved to suppress the increase of legionellae in cooling-tower water, and thus are useful in preventing the outbreak of legionellosis due to inhalation of contaminated aerosol from the cooling tower system.

  2. Analytical Assessment of Environmental Impact for APR1400DC UHS Cooling Tower

    Lee, Jaiho [KHNP-Central Research Institute, Daejeon (Korea, Republic of)


    Hot process water is pumped from the plant process to the cooling towers. Heat is rejected through evaporation of the process water, interacting with ambient air blown upward by fans.. Plumes generated from exit ports of the cooling tower may have adverse effects on the environment, such as deposition of cooling tower drift release, fogging, icing, shadowing, and ground-level temperature and humidity increase. These kinds of environmental impact of the cooling tower are linked closely with the dispersion of the cooling tower plumes. In this respect, predicting the behavior of the plumes has become one of the most important issues in the environmental assessments of the cooling towers. The SACTI (seasonal/annual cooling tower impact) model is an analytical tool to predict the environmental effect of cooling tower, which was developed by Argonne National Laboratory and University of Illinois with support from EPRI (electric power research institute). The initial version of SACTI has been widely used to assess the environmental effect of cooling towers in many industrial fields such as steam power plants and NPPs. Guo et. al. investigated impact of heat rejection and cooling tower height on plume dispersion using the SACTI model, for the purpose of the future construction of inland NPPs. They found that increasing cooling tower height decreases the plume length and height frequencies. Their simulation results showed that the increase in heat rejection increases the plum radius frequency. The APR1400DC is an advanced light water reactor developed for the purpose of NRC-DC (design certification). The cooling towers for APR1400DC UHS consist of two linear mechanical draft cooling towers (LMDCTs). The LMDCT for APR1400DC UHS is conceptually designed because the plant site has not been decided yet. In the present study, the dependency of plume dispersion on the number of cooling towers is investigated using SACTI-2-beta, for predicting annual environmental effect of APR

  3. Wastewater reuse as cooling-tower makeup: Final report

    Goldstein, D.; Wei, I.; Casana, J.


    The objectives of this program are to document electric utility experience and concerns on the use of municipal wastewater as makeup to cooling towers and to identify areas lacking sufficient information for their application as well as to identify problem areas. Current users of municipal wastewater in electric utility cooling towers have been contacted and the literature has been reviewed. In addition, literature on the reuse of industrial wastewater has been reviewed. The findings are summarized in this report with emphasis on the use of municipal wastewater in electric utility cooling towers. It was found that this practice has been going on for sufficient time at sufficient places that the problems are fairly well understood. Scale formation by calcium phosphate is a problem. It is controlled by pH reduction or by removal of phosphate and suggested techniques are given. Fouling by slime is a problem. It is controlled by heavy doses of chlorine and other biocides or by mechanical and other non-chemical means without use of any biocide. Foaming, corrosion and blowdown disposal are not problems. There are a number of problem areas where more information is desired to establish a higher level of confidence in using sewage water as makeup. Three areas of research are recommended: (1) a study comparing the technological and environmental problems and costs of various technologies used to control the formation of biological slime, (2) laboratory and pilot scale testing to verify the prediction techniques for phosphate precipitation, and (3) to determine whether the health hazards of using sewage water are worse than the use of normal waters.

  4. Reducing the risk of Legionnaires' disease associated with cooling towers

    Freije, M.R. [HC Information Resources Inc., Carlsbad, CA (United States)


    To reduce the health and legal risks associated with Legionnaires' disease, facility managers should take steps to minimize Legionella bacteria in plumbing systems, open industrial equipment, water features, cooling towers, and other aerosolizing water systems. The risk of Legionnaires' disease associated with cooling towers can be reduced by controlling Legionella bacteria in cooling water and preventing transmission of the bacteria from towers to people. This paper presents nine reasonable ways to accomplish these goals. (orig.)

  5. Coagulation chemistries for silica removal from cooling tower water.

    Nyman, May Devan; Altman, Susan Jeanne; Stewart, Tom


    The formation of silica scale is a problem for thermoelectric power generating facilities, and this study investigated the potential for removal of silica by means of chemical coagulation from source water before it is subjected to mineral concentration in cooling towers. In Phase I, a screening of many typical as well as novel coagulants was carried out using concentrated cooling tower water, with and without flocculation aids, at concentrations typical for water purification with limited results. In Phase II, it was decided that treatment of source or make up water was more appropriate, and that higher dosing with coagulants delivered promising results. In fact, the less exotic coagulants proved to be more efficacious for reasons not yet fully determined. Some analysis was made of the molecular nature of the precipitated floc, which may aid in process improvements. In Phase III, more detailed study of process conditions for aluminum chloride coagulation was undertaken. Lime-soda water softening and the precipitation of magnesium hydroxide were shown to be too limited in terms of effectiveness, speed, and energy consumption to be considered further for the present application. In Phase IV, sodium aluminate emerged as an effective coagulant for silica, and the most attractive of those tested to date because of its availability, ease of use, and low requirement for additional chemicals. Some process optimization was performed for coagulant concentration and operational pH. It is concluded that silica coagulation with simple aluminum-based agents is effective, simple, and compatible with other industrial processes.

  6. Flue gas injection control of silica in cooling towers.

    Brady, Patrick Vane; Anderson, Howard L., Jr.; Altman, Susan Jeanne


    Injection of CO{sub 2}-laden flue gas can decrease the potential for silica and calcite scale formation in cooling tower blowdown by lowering solution pH to decrease equilibrium calcite solubility and kinetic rates of silica polymerization. Flue gas injection might best inhibit scale formation in power plant cooling towers that use impaired makeup waters - for example, groundwaters that contain relatively high levels of calcium, alkalinity, and silica. Groundwaters brought to the surface for cooling will degas CO{sub 2} and increase their pH by 1-2 units, possibly precipitating calcite in the process. Recarbonation with flue gas can lower the pHs of these fluids back to roughly their initial pH. Flue gas carbonation probably cannot lower pHs to much below pH 6 because the pHs of impaired waters, once outgassed at the surface, are likely to be relatively alkaline. Silica polymerization to form scale occurs most rapidly at pH {approx} 8.3 at 25 C; polymerization is slower at higher and lower pH. pH 7 fluids containing {approx}220 ppm SiO{sub 2} require > 180 hours equilibration to begin forming scale whereas at pH 8.3 scale formation is complete within 36 hours. Flue gas injection that lowers pHs to {approx} 7 should allow substantially higher concentration factors. Periodic cycling to lower recoveries - hence lower silica concentrations - might be required though. Higher concentration factors enabled by flue gas injection should decrease concentrate volumes and disposal costs by roughly half.

  7. Analysis of the evaporative towers cooling system of a coal-fired power plant

    Laković Mirjana S.


    Full Text Available The paper presents a theoretical analysis of the cooling system of a 110 MW coal-fired power plant located in central Serbia, where eight evaporative towers cool down the plant. An updated research on the evaporative tower cooling system has been carried out to show the theoretical analysis of the tower heat and mass balance, taking into account the sensible and latent heat exchanged during the processes which occur inside these towers. Power plants which are using wet cooling towers for cooling condenser cooling water have higher design temperature of cooling water, thus the designed condensing pressure is higher compared to plants with a once-through cooling system. Daily and seasonal changes further deteriorate energy efficiency of these plants, so it can be concluded that these plants have up to 5% less efficiency compared to systems with once-through cooling. The whole analysis permitted to evaluate the optimal conditions, as far as the operation of the towers is concerned, and to suggest an improvement of the plant. Since plant energy efficiency improvement has become a quite common issue today, the evaluation of the cooling system operation was conducted under the hypothesis of an increase in the plant overall energy efficiency due to low cost improvement in cooling tower system.

  8. Mathematical model and calculation of water-cooling efficiency in a film-filled cooling tower

    Laptev, A. G.; Lapteva, E. A.


    Different approaches to simulation of momentum, mass, and energy transfer in packed beds are considered. The mathematical model of heat and mass transfer in a wetted packed bed for turbulent gas flow and laminar wave counter flow of the fluid film in sprinkler units of a water-cooling tower is presented. The packed bed is represented as the set of equivalent channels with correction to twisting. The idea put forward by P. Kapitsa on representation of waves on the interphase film surface as elements of the surface roughness in interaction with the gas flow is used. The temperature and moisture content profiles are found from the solution of differential equations of heat and mass transfer written for the equivalent channel with the volume heat and mass source. The equations for calculation of the average coefficients of heat emission and mass exchange in regular and irregular beds with different contact elements, as well as the expression for calculation of the average turbulent exchange coefficient are presented. The given formulas determine these coefficients for the known hydraulic resistance of the packed bed element. The results of solution of the system of equations are presented, and the water temperature profiles are shown for different sprinkler units in industrial water-cooling towers. The comparison with experimental data on thermal efficiency of the cooling tower is made; this allows one to determine the temperature of the cooled water at the output. The technical solutions on increasing the cooling tower performance by equalization of the air velocity profile at the input and creation of an additional phase contact region using irregular elements "Inzhekhim" are considered.

  9. Numerical simulation on internal and external flow field of a SCAL indirect air cooling tower

    TIAN Songfeng; CHAI Yanqin; XIANG Tongqiong; ZHOU Guangsha


    According to the actual size of cooling tube bundle and the arrangement of cooling triangle of a surface condenser aluminum exchangers (SCAL)natural draft cooling tower,the geometric model of heat transfer elements at the tower bottom was established.On the basis of the RNG k-εturbulence model and porous medium model,three-dimensional numerical simulation was carried out for the inner and external flow field of the air cooling tower,to investigate the influence of environmental conditions on the tower's operation performance.The results show that,with an increase in ambient wind speed,the inlet air speed at windward side of the tower increases gradually,while that at crosswind side and lee side decreases and tends to be obvious;the tower ventilation rate and outlet air speed increases at first and then decreases,and their maximum values appear when the wind speed is 2 m/s.

  10. Fire analog: a comparison between fire plumes and energy center cooling tower plumes

    Orgill, M.M.


    Thermal plumes or convection columns associated with large fires are compared to thermal plumes from cooling towers and proposed energy centers to evaluate the fire analog concept. Energy release rates of mass fires are generally larger than for single or small groups of cooling towers but are comparable to proposed large energy centers. However, significant physical differences exist between cooling tower plumes and fire plumes. Cooling tower plumes are generally dominated by ambient wind, stability and turbulence conditions. Fire plumes, depending on burning rates and other factors, can transform into convective columns which may cause the fire behavior to become more violent. This transformation can cause strong inflow winds and updrafts, turbulence and concentrated vortices. Intense convective columns may interact with ambient winds to create significant downwind effects such as wakes and Karman vortex streets. These characteristics have not been observed with cooling tower plumes to date. The differences in physical characteristics between cooling tower and fire plumes makes the fire analog concept very questionable even though the approximate energy requirements appear to be satisfied in case of large energy centers. Additional research is suggested in studying the upper-level plume characteristics of small experimental fires so this information can be correlated with similar data from cooling towers. Numerical simulation of fires and proposed multiple cooling tower systems could also provide comparative data.

  11. The use of an electrical-fluid dynamic parameter in cooling tower

    Sirena, J.A. [Univ. Nacional de Cordoba (Argentina). Facultad de Ciencias Exactas


    An Electrical-Fluid Dynamic quality parameter is defined for a mechanical draft type cooling tower. It allows to evaluate the efficiency of the transformation of the electrical power input into kinetic energy of the air flow. It could also be used to calculate the active electrical power of the tower at different working conditions. Results obtained through tests in a small counterflow water cooling tower are shown.

  12. Ecological impact of chloro-organics produced by chlorination of cooling tower waters

    Jolley, R L; Cumming, R B; Pitt, W W; Taylor, F G; Thompson, J E; Hartmann, S J


    Experimental results of the initial assessment of chlorine-containing compounds in the blowdown from cooling towers and the possible mutagenic activity of these compounds are reported. High-resolution liquid chromatographic separations were made on concentrates of the blowdown from the cooling tower at the High Flux Isotope Reactor (HFIR) and from the recirculating water system for the cooling towers at the Oak Ridge Gaseous Diffusion Plant (ORGDP), Oak Ridge, Tennessee. The chromatograms of chlorinated cooling waters contained numerous uv-absorbing and cerate-oxidizable constituents that are now being processed through a multicomponent identification procedure. Concentrates of the chlorinated waters are also being examined for mutagenic activity.



    The flow field in the hyperbolic natural draft wet-cooling tower, which has great effects on the economy and security of power plant, was studied through numerical simulation. The mathematical model was established and analyzed in order to optimize the cooling-tower and to evaluate its efficiency. Various working conditions were considered and compared with each other, such as the circulating water flux, air temperature and tower resistance. It is concluded that when the cooling-tower runs without wind, there is a vacuum region inside the tower and the pressure rises with the increase of the tower height. Meanwhile, the inner flow field is axisymmetrical. The air velocity achieves its climax at the axis. It is also found that the effect of circulating water temperature is equivalent to that of the water flux.

  14. Ammonia as an intermediate heat exchange fluid for dry cooled towers

    Allemann, R T; Johnson, B M; Smith, G C


    The feasibility of using ammonia as an intermediate heat exchange fluid, i.e. between the power plant and the dry cooling tower was studied. Information is included on the advantages and disadvantages of using ammonia, design criteria for such a dry cooling system, and a comparative cost projection for the components and overall system. The results showed that the ammonia heat exchange system could save half the cost of transporting the coolant as compared with a conventional indirect cooled dry system, that the heat exchanger cost would be 20 percent less, and the tower would be smaller and cheaper. The condenser/reboiler would be more expensive. Overall a 25 percent saving in total system capital cost and $500 K/yr. in operating costs are projected as compared with wet/dry deluge system of identical capability. Also there are no freezing problems with the ammonia system. It is recommended that: a demonstration unit be designed; performance testing on components be undertaken; a design optimization code for dry/wet systems be developed; and that a test loop be constructed and operated. (LCL)

  15. Counter flow induced draft cooling tower option for supercritical carbon dioxide Brayton cycle

    Pidaparti, Sandeep R., E-mail: [Georgia Institute of Technology, George W. Woodruff School of Mechanical Engineering, Atlanta, GA 30332 (United States); Moisseytsev, Anton; Sienicki, James J. [Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States); Ranjan, Devesh, E-mail: [Georgia Institute of Technology, George W. Woodruff School of Mechanical Engineering, Atlanta, GA 30332 (United States)


    Highlights: • A code was developed to investigate the various aspects of using cooling tower for S-CO{sub 2} Brayton cycles. • Cooling tower option to reject heat is quantitatively compared to the direct water cooling and dry air cooling options. • Optimum water conditions resulting in minimal plant capital cost per unit power consumption are calculated. - Abstract: A simplified qualitative analysis was performed to investigate the possibility of using counter flow induced draft cooling tower option to reject heat from the supercritical carbon dioxide Brayton cycle for advanced fast reactor (AFR)-100 and advanced burner reactor (ABR)-1000 plants. A code was developed to estimate the tower dimensions, power and water consumption, and to perform economic analysis. The code developed was verified against a vendor provided quotation and is used to understand the effect of ambient air and water conditions on the design of cooling tower. The calculations indicated that there exists optimum water conditions for given ambient air conditions which will result in minimum power consumption, thereby increasing the cycle efficiency. A cost-based optimization technique is used to estimate the optimum water conditions which will improve the overall plant economics. A comparison of different cooling options for the S-CO{sub 2} cycle indicated that the cooling tower option is a much more practical and economical option compared to the dry air cooling or direct water cooling options.

  16. Theoretical and experimental study of a cross-flow induced-draft cooling tower

    Abo Elazm Mahmoud Mohamed


    Full Text Available The main objective of this study is to find a proper solution for the cross-flow water cooling tower problem, also to find an empirical correlation's controlling heat and mass transfer coefficients as functions of inlet parameters to the tower. This is achieved by constructing an experimental rig and a computer program. The computer simulation solves the problem numerically. The apparatus used in this study comprises a cross-flow cooling tower. From the results obtained, the 'characteristic curve' of cross-flow cooling towers was constructed. This curve is very helpful for designers in order to find the actual value of the number of transfer units, if the values of inlet water temperature or inlet air wet bulb temperature are changed. Also an empirical correlation was conducted to obtain the required number of transfer units of the tower in hot water operation. Another correlation was found to obtain the effectiveness in the wet bulb operation.

  17. Cooling tower and plume modeling for satellite remote sensing applications

    Powers, B.J.


    It is often useful in nonproliferation studies to be able to remotely estimate the power generated by a power plant. Such information is indirectly available through an examination of the power dissipated by the plant. Power dissipation is generally accomplished either by transferring the excess heat generated into the atmosphere or into bodies of water. It is the former method with which we are exclusively concerned in this report. We discuss in this report the difficulties associated with such a task. In particular, we primarily address the remote detection of the temperature associated with the condensed water plume emitted from the cooling tower. We find that the effective emissivity of the plume is of fundamental importance for this task. Having examined the dependence of the plume emissivity in several IR bands and with varying liquid water content and droplet size distributions, we conclude that the plume emissivity, and consequently the plume brightness temperature, is dependent upon not only the liquid water content and band, but also upon the droplet size distribution. Finally, we discuss models dependent upon a detailed point-by-point description of the hydrodynamics and thermodynamics of the plume dynamics and those based upon spatially integrated models. We describe in detail a new integral model, the LANL Plume Model, which accounts for the evolution of the droplet size distribution. Some typical results obtained from this model are discussed.

  18. 2D study of wind forces around multiple cooling towers using ...


    2D study of wind forces around multiple cooling towers using computational ... Due to the complexity of wind turbulence near ground (Atmospheric Boundary. Layer), the .... In the past, before the computer revolution, the analysis used to be.

  19. Bevel gear drives in cooling tower fans; Kegelstirnradgetriebe in Luefterantrieben fuer Kuehltuerme

    Reichenbach, M.


    Cooling towers of petrochemical systems require high-quality drives which are also energy-saving and require low maintenance. The contribution goes into detail about customized bevel gear drives for cooling tower fans. [German] Um optimale Produkte zu erhalten, sind hochwertige Antriebe unabdingbar. Bei Kuehltuermen in petrochemischen Anlagen kommt es ausserdem auf eine energiesparende und wartungsarme Ausfuehrung von Zahnradgetrieben an. Im Folgenden soll auf das besondere Einsatzgebiet von massgeschneiderten Kegelstirnradgetrieben in Luefterantrieben naeher eingegangen werden. (orig.)

  20. Research on the Flow-Head Characteristics of the Turbine Driving Fan in Cooling tower

    Li Yanpin


    Full Text Available The flow-head characteristics of the special turbine in cooling tower are very different from the general power turbines’. This study has analyzed the former theoretically and proposed the theoretical formula of the head-flow. At the same time, the paper has studied the characteristics of the flow-head using the CFD method. The tests results have proved the principle of the flow-head of the turbine in cooling tower.

  1. Geodetic works on the construction of cooling tower of TEŠ 6

    Kolarič, Andrej


    The thesis discusses with geodetic works on the construction of cooling tower of sixth block in Šoštanj thermal power plant. It presents briefly the thermal power plant and describes the process of construction of the cooling tower. The establishment of basic surveying network stakeout is explained. It is also contains a full description of the stakeout procedures. Paper states the requirements and accuracy of stakeout and describes practical examples. It shows the concrete implementation ...

  2. Heat transfer enhancement in a natural draft dry cooling tower under crosswind operation with heterogeneous water distribution

    Goodarzi, Mohsen; Amooie, Hossein [Bu-Ali Sina Univ., Hamedan (Iran, Islamic Republic of). Dept. of Mechanical Engineering


    Crosswind significantly decreases cooling efficiency of a natural draft dry cooling tower. The possibility of improving cooling efficiency with heterogeneous water distribution within the cooling tower radiators under crosswind condition is analysed. A CFD approach was used to model the flow field and heat transfer phenomena within the cooling tower and airflow surrounding the cooling tower. A mathematical model was developed from various CFD results. Having used a trained Genetic Algorithm with the result of mathematical model, the best water distribution was found among the others. Remodeling the best water distribution with the CFD approach showed that the highest enhancement of the heat transfer compared to the usual uniform water distribution.

  3. Dialogues in the COOL Project

    Stalpers, S.I.P.; Kroeze, C.


    The Climate Options for the Long-term (COOL) Project is a participatory integrated assessment (PIA) comprising extensive dialogues at three levels: national, European and global. The objective of the COOL Project was to ‘develop strategic notions on how to achieve drastic reductions of greenhouse ga

  4. Effect of solar radiation on the performance of cross flow wet cooling tower in hot climate of Iran

    Banooni, Salem; Chitsazan, Ali


    In some cities such as Ahvaz-Iran, the solar radiation is very high and the annual-mean-daily of the global solar radiation is about 17.33 MJ m2 d-1. Solar radiation as an external heat source seems to affect the thermal performance of the cooling towers. Usually, in modeling cooling tower, the effects of solar radiation are ignored. To investigate the effect of sunshade on the performance and modeling of the cooling tower, the experiments were conducted in two different states, cooling towers with and without sunshade. In this study, the Merkel's approach and finite difference technique are used to predict the thermal behavior of cross flow wet cooling tower without sunshade and the results are compared with the data obtained from the cooling towers with and without sunshade. Results showed that the sunshade is very efficient and it reduced the outlet water temperature, the approach and the water exergy of the cooling tower up to 1.2 °C, 15 and 1.1 %, respectively and increased the range and the efficiency of the cooling tower up to 29 and 37 %, respectively. Also, the sunshade decreased the error between the experimental data of the cooling tower with sunshade and the modeling results of the cooling tower without sunshade 1.85 % in average.

  5. A New Cooling Tower of Spraying Ventilation%一种新型喷雾通风冷却塔

    胡国林; 李丽萍


    The distinctive working principle of a new cooling tower with spraying ventilation is elaborated and comparison to the mechanical ventilation based tower is made. Some personal opinions on the pressure regulation in operation of this equipment are alsoproposed.

  6. Simultaneous effects of water spray and crosswind on performance of natural draft dry cooling tower

    Ahmadikia Hossein


    Full Text Available To investigate the effect of water spray and crosswind on the effectiveness of the natural draft dry cooling tower (NDDCT, a three-dimensional model has been developed. Efficiency of NDDCT is improved by water spray system at the cooling tower entrance for high ambient temperature condition with and without crosswind. The natural and forced heat convection flow inside and around the NDDCT is simulated numerically by solving the full Navier-Stokes equations in both air and water droplet phases. Comparison of the numerical results with one-dimensional analytical model and the experimental data illustrates a well-predicted heat transfer rate in the cooling tower. Applying water spray system on the cooling tower radiators enhances the cooling tower efficiency at both no wind and windy conditions. For all values of water spraying rate, NDDCTs operate most effectively at the crosswind velocity of 3m/s and as the wind speed continues to rise to more than 3 m/s up to 12 m/s, the tower efficiency will decrease by approximately 18%, based on no-wind condition. The heat transfer rate of radiator at wind velocity 10 m/s is 11.5% lower than that of the no wind condition. This value is 7.5% for water spray rate of 50kg/s.

  7. Disinfection of bacterial biofilms in pilot-scale cooling tower systems.

    Liu, Yang; Zhang, Wei; Sileika, Tadas; Warta, Richard; Cianciotto, Nicholas P; Packman, Aaron I


    The impact of continuous chlorination and periodic glutaraldehyde treatment on planktonic and biofilm microbial communities was evaluated in pilot-scale cooling towers operated continuously for 3 months. The system was operated at a flow rate of 10,080 l day(-1). Experiments were performed with a well-defined microbial consortium containing three heterotrophic bacteria: Pseudomonas aeruginosa, Klebsiella pneumoniae and Flavobacterium sp. The persistence of each species was monitored in the recirculating cooling water loop and in biofilms on steel and PVC coupons in the cooling tower basin. The observed bacterial colonization in cooling towers did not follow trends in growth rates observed under batch conditions and, instead, reflected differences in the ability of each organism to remain attached and form biofilms under the high-through flow conditions in cooling towers. Flavobacterium was the dominant organism in the community, while P. aeruginosa and K. pneumoniae did not attach well to either PVC or steel coupons in cooling towers and were not able to persist in biofilms. As a result, the much greater ability of Flavobacterium to adhere to surfaces protected it from disinfection, whereas P. aeruginosa and K. pneumoniae were subject to rapid disinfection in the planktonic state.

  8. Water vapour rises from the cooling towers for the ATLAS detector at Point 1

    Brice, Maximilien


    Electronics on the ATLAS detector produce heat when the experiment is running. An elaborate cooling system keeps the detector from overheating. On the surface, the warm water vapour that rises from the detector 100metres underground is clearly visible from the ATLAS cooling towers on the CERN Meyrin site in Switzerland.

  9. Demolition technique of high thin-wall hyperbolic reinforced concrete cool tower by directional controlled blasting

    Luo Yong; Cui Xiaorong; Lu Hua


    Based on blasting demolition of high thin-wall hyperbolic reinforced concrete cool tower,by virtue of engi-neering practice of blasting the tube concrete structures,the analysis and research were made on the mechanism of cool tower collapse through selecting blasting parameters and selecting gap form,gap size and gap angle.The cool tower was twisted,collapsed directionally and broken weU according to the design requirements.The expected results and purpo-ses of blasting were obtained with no back blow,total blasted pile approximates to 4 ~ 5 m,no occurrence of flying stones and no damage to fixed buildings and equipment,the large-sized hyperbolic thin-wall reinforced concrete cool towers are twisted during blasting and it collapses well with good breaking.The test and measurement of blasting vibra-ting velocity was carried out during blasting and the measuring results are much less than critical values specified by Safety Regulations for Blasting.The study shows that gap form,gap size and gap angle are the key factors to cool tower collapse and will give beneficial references to related theoretical study and field application.

  10. Optimum Design and Operation of an HVAC Cooling Tower for Energy and Water Conservation

    Clemente García Cutillas


    Full Text Available The energy consumption increase in the last few years has contributed to developing energy efficiency policies in many countries, the main goal of which is decreasing CO 2 emissions. One of the reasons for this increment has been caused by the use of air conditioning systems due to new comfort standards. In that regard, cooling towers and evaporative condensers are presented as efficient devices that operate with low-level water temperature. Moreover, the energy consumption and the cost of the equipment are lower than other systems like air condensers at the same operation conditions. This work models an air conditioning system in TRNSYS software, the main elements if which are a cooling tower, a water-water chiller and a reference building. The cooling tower model is validated using experimental data in a pilot plant. The main objective is to implement an optimizing control strategy in order to reduce both energy and water consumption. Furthermore a comparison between three typical methods of capacity control is carried out. Additionally, different cooling tower configurations are assessed, involving six drift eliminators and two water distribution systems. Results show the influence of optimizing the control strategy and cooling tower configuration, with a maximum energy savings of 10.8% per story and a reduction of 4.8% in water consumption.

  11. Concept of CFD model of natural draft wet-cooling tower flow

    Hyhlík T.


    Full Text Available The article deals with the development of CFD model of natural draft wet-cooling tower flow. The physical phenomena taking place within a natural draft wet cooling tower are described by the system of conservation law equations along with additional equations. The heat and mass transfer in the counterflow wet-cooling tower fill are described by model [1] which is based on the system of ordinary differential equations. Utilization of model [1] of the fill allows us to apply commonly measured fill characteristics as shown by [2].The boundary value problem resulting from the fill model is solved separately. The system of conservation law equations is interlinked with the system of ordinary differential equations describing the phenomena occurring in the counterflow wet-cooling tower fill via heat and mass sources and via boundary conditions. The concept of numerical solution is presented for the quasi one dimensional model of natural draft wet-cooling tower flow. The simulation results are shown.

  12. A Comparative Analysis of Three Water Treatment Programs for Cooling Tower Systems


    Gallic Acid Powder (item 2063) METHOD: It is necessary to follow the instructions furnished with the conductivity meter that is being used . The...the location and costs of AFLC towers. 2 Definition of Terms Terms commonly used in cooling tower water treatment. Acid : A substance that dissolves...the sulfuric acid program. This program is still indorsed by Air Force Regulation 91-40. System operators use sulfuric acid to lower the pH and


    Lee, S.; Garrett, A.; Bollinger, J.


    Mechanical draft cooling towers are designed to cool process water via sensible and latent heat transfer to air. Heat and mass transfer take place simultaneously. Heat is transferred as sensible heat due to the temperature difference between liquid and gas phases, and as the latent heat of the water as it evaporates. Mass of water vapor is transferred due to the difference between the vapor pressure at the air-liquid interface and the partial pressure of water vapor in the bulk of the air. Equations to govern these phenomena are discussed here. The governing equations are solved by taking a computational fluid dynamics (CFD) approach. The purpose of the work is to develop a three-dimensional CFD model to evaluate the flow patterns inside the cooling tower cell driven by cooling fan and wind, considering the cooling fans to be on or off. Two types of the cooling towers are considered here. One is cross-flow type cooling tower located in A-Area, and the other is counterflow type cooling tower located in H-Area. The cooling tower located in A-Area is mechanical draft cooling tower (MDCT) consisting of four compartment cells as shown in Fig. 1. It is 13.7m wide, 36.8m long, and 9.4m high. Each cell has its own cooling fan and shroud without any flow communications between two adjacent cells. There are water distribution decks on both sides of the fan shroud. The deck floor has an array of about 25mm size holes through which water droplet falls into the cell region cooled by the ambient air driven by fan and wind, and it is eventually collected in basin area. As shown in Fig. 1, about 0.15-m thick drift eliminator allows ambient air to be humidified through the evaporative cooling process without entrainment of water droplets into the shroud exit. The H-Area cooling tower is about 7.3 m wide, 29.3 m long, and 9.0 m high. Each cell has its own cooling fan and shroud, but each of two corner cells has two panels to shield wind at the bottom of the cells. There is some

  14. Influence of thermal flow field of cooling tower on recirculation ratio of a direct air-cooled system for a power plant

    Zhao Wanli; Liu Peiqing


    In order to get thermal flow field of direct air-cooled system,the hot water was supplied to the model of direct air-cooled condenser(ACC).The particle image velocimetery(PIV)experiments were carried out to get thermal flow field of a ACC under different conditions in low velocity wind tunnel,at the same time,the recirculation ratio at cooling tower was measured,so the relationship between flow field characteristics and recirculation ratio of cooling tower can be discussed.From the results we can see that the flow field configuration around cooling tower has great effects on average recirculation ratio under cooling tower.The eddy formed around cooling tower is a key reason that recireulation pro-duces.The eddy intensity relates to velocity magnitude and direction angle,and the configuration of eddy lies on the ge-ometry size of cooling tower.So changing the flow field configuration around cooling tower reasonably can decrease recir-culation ratio under cooling tower,and heat dispel effect of ACC can also be improved.

  15. State of the art cooling tower technology in geothermal power applications

    Mortensen, K.P. [Marley Cooling Tower Company, Overland Park, KS (United States)


    Several cooling tower design configurations, including crossflow and counterflow, splash and film filled, have been used in geothermal applications over the years with varying degrees of longterm success. This paper examines the special water quality conditions expected in geothermal power generation, describes the current theory on materials and fill types most suitable for this application, and relates field experience to the theory. The goal is to arrive at current, but evolving {open_quotes}best practice{close_quotes} application rules for cooling tower designs in geothermal application. This means providing the most economically and thermally efficient cooling towers to end users, and having those selections provide good long-term system viability with reasonable maintenance practices.

  16. Startup of air-cooled condensers and dry cooling towers at low temperatures of the cooling air

    Milman, O. O.; Ptakhin, A. V.; Kondratev, A. V.; Shifrin, B. A.; Yankov, G. G.


    The problems of startup and performance of air-cooled condensers (ACC) and dry cooling towers (DCT) at low cooling air temperatures are considered. Effects of the startup of the ACC at sub-zero temperatures are described. Different options of the ACC heating up are analyzed, and examples of existing technologies are presented (electric heating, heating up with hot air or steam, and internal and external heating). The use of additional heat exchanging sections, steam tracers, in the DCT design is described. The need for high power in cases of electric heating and heating up with hot air is noted. An experimental stand for research and testing of the ACC startup at low temperatures is described. The design of the three-pass ACC unit is given, and its advantages over classical single-pass design at low temperatures are listed. The formation of ice plugs inside the heat exchanging tubes during the start-up of ACC and DCT at low cooling air temperatures is analyzed. Experimental data on the effect of the steam flow rate, steam nozzle distance from the heat-exchange surface, and their orientation in space on the metal temperature were collected, and test results are analyzed. It is noted that the surface temperature at the end of the heat up is almost independent from its initial temperature. Recommendations for the safe start-up of ACCs and DCTs are given. The heating flow necessary to sufficiently heat up heat-exchange surfaces of ACCs and DCTs for the safe startup is estimated. The technology and the process of the heat up of the ACC with the heating steam external supply are described by the example of the startup of the full-scale section of the ACC at sub-zero temperatures of the cooling air, and the advantages of the proposed start-up technology are confirmed.

  17. Discussion on Calculation of Structure Stability of Super Large Cooling Tower%超大型冷却塔结构稳定性计算的探讨

    董胜宪; 戴永志


    Hyperbolic natural draft cooling tower is an important project in construction of electricity, with power construction in China's booming, stand-alone power plants installed capacity increased, cooling tower of power plant have gone from cooling tower of large and medium to very large cooling towers. Very large cooling tower structure stability already mentioned work on our agenda, should be a matter of attention.%双曲线自然通风冷却塔是电力建设中的一项重要工程,随着我国电力建设事业的蓬勃发展,发电厂单机装机容量的增大,电厂内的冷却塔已从过去的大中型冷却塔转为超大型冷却塔。超大型冷却塔结构稳定性工作已提到我们的议事日程上,应该引起各方面的重视。

  18. Startup of Pumping Units in Process Water Supplies with Cooling Towers at Thermal and Nuclear Power Plants

    Berlin, V. V., E-mail:; Murav’ev, O. A., E-mail:; Golubev, A. V., E-mail: [National Research University “Moscow State University of Civil Engineering,” (Russian Federation)


    Aspects of the startup of pumping units in the cooling and process water supply systems for thermal and nuclear power plants with cooling towers, the startup stages, and the limits imposed on the extreme parameters during transients are discussed.

  19. 300 MW机组利旧冷却塔的研究和运用%Utilization of Old Small Cooling Tower in a New 300 MW Generation Unit



    The feasibility of utilizing old smaller cooling tower in the construction pro-cess of large thermal power unit was studied. Utilization of old small cooling tower not only shortened the construction period but also reduced the project cost.%对大机组建设过程中利用小机组冷却塔的可行性进行了研究。利用旧的小机组冷却塔后缩短了施工工期,降低了工程造价。

  20. Pilot-scale cooling tower to evaluate corrosion, scaling, and biofouling control strategies for cooling system makeup water.

    Chien, S H; Hsieh, M K; Li, H; Monnell, J; Dzombak, D; Vidic, R


    Pilot-scale cooling towers can be used to evaluate corrosion, scaling, and biofouling control strategies when using particular cooling system makeup water and particular operating conditions. To study the potential for using a number of different impaired waters as makeup water, a pilot-scale system capable of generating 27,000 kJ∕h heat load and maintaining recirculating water flow with a Reynolds number of 1.92 × 10(4) was designed to study these critical processes under conditions that are similar to full-scale systems. The pilot-scale cooling tower was equipped with an automatic makeup water control system, automatic blowdown control system, semi-automatic biocide feeding system, and corrosion, scaling, and biofouling monitoring systems. Observed operational data revealed that the major operating parameters, including temperature change (6.6 °C), cycles of concentration (N = 4.6), water flow velocity (0.66 m∕s), and air mass velocity (3660 kg∕h m(2)), were controlled quite well for an extended period of time (up to 2 months). Overall, the performance of the pilot-scale cooling towers using treated municipal wastewater was shown to be suitable to study critical processes (corrosion, scaling, biofouling) and evaluate cooling water management strategies for makeup waters of complex quality.

  1. ATLAS' major cooling project


    In 2005, a considerable effort has been put into commissioning the various units of ATLAS' complex cryogenic system. This is in preparation for the imminent cooling of some of the largest components of the detector in their final underground configuration. The liquid helium and nitrogen ATLAS refrigerators in USA 15. Cryogenics plays a vital role in operating massive detectors such as ATLAS. In many ways the liquefied argon, nitrogen and helium are the life-blood of the detector. ATLAS could not function without cryogens that will be constantly pumped via proximity systems to the superconducting magnets and subdetectors. In recent weeks compressors at the surface and underground refrigerators, dewars, pumps, linkages and all manner of other components related to the cryogenic system have been tested and commissioned. Fifty metres underground The helium and nitrogen refrigerators, installed inside the service cavern, are an important part of the ATLAS cryogenic system. Two independent helium refrigerators ...

  2. Cooling Tower Engineering in Thermal Power Generation%火力发电冷却塔工程



    This paper expounds the working principle of thermal power cooling tower and introduces the construction scheme and safety facilities of the cooling tower.%阐述火力发电冷却塔的工作原理。同时,说明冷却塔施工作业方案及安全设施。

  3. Hydraulic design of a low-specific speed Francis runner for a hydraulic cooling tower

    Ruan, H.; Luo, X. Q.; Liao, W. L.; Zhao, Y. P.


    The air blower in a cooling tower is normally driven by an electromotor, and the electric energy consumed by the electromotor is tremendous. The remaining energy at the outlet of the cooling cycle is considerable. This energy can be utilized to drive a hydraulic turbine and consequently to rotate the air blower. The purpose of this project is to recycle energy, lower energy consumption and reduce pollutant discharge. Firstly, a two-order polynomial is proposed to describe the blade setting angle distribution law along the meridional streamline in the streamline equation. The runner is designed by the point-to-point integration method with a specific blade setting angle distribution. Three different ultra-low-specificspeed Francis runners with different wrap angles are obtained in this method. Secondly, based on CFD numerical simulations, the effects of blade setting angle distribution on pressure coefficient distribution and relative efficiency have been analyzed. Finally, blade angles of inlet and outlet and control coefficients of blade setting angle distribution law are optimal variables, efficiency and minimum pressure are objective functions, adopting NSGA-II algorithm, a multi-objective optimization for ultra-low-specific speed Francis runner is carried out. The obtained results show that the optimal runner has higher efficiency and better cavitation performance.


    A. Haddad


    Cooling towers are extensively used to evacuate large quantities of heat at modest temperatures through a change of phase of the flowing cooling fluid. Based on this classical principle, the present study investigates the influence of salty water on the heat exchange produced. For that purpose, experiments are carried out using fresh and salty water. Furthermore, a comparison with the results produced through an approach involving the solution of energy equation involving the flow...

  5. Costs and cost algorithms for dry cooling tower systems

    Ard, P.A.; Henager, C.H.; Pratt, D.R.; Wiles, L.E.


    Costs were obtained and cast models prepared for the major components beyond the turbine exhaust flange of a dry cooling system using either water or ammonia as the intermediate heat exchange fluid. (LCL)


    K. V. Dobrego


    Full Text Available Modern Cooling Towers (CT may utilize different aerodynamic elements (deflectors, windbreak walls etc. aimed to improvement of its heat performance especially at the windy conditions. In this paper the effect of flow rotation in overshower zone of CT and windbreak walls on a capacity of tower evaporating unit in the windy condition is studied numerically. Geometry of the model corresponds to real Woo-Jin Power station, China. Analogy of heat and mass transfer was used that allowed to consider aerodynamic of one-dimension flow and carried out detailed 3D calculations applying modern PC. Heat transfer coefficient of irrigator and its hydrodynamic resistance were established according to experimental data on total air rate in cooling tower. Numerical model is tested and verified with experimental data.Nonlinear dependence of CT thermal performance on wind velocity is demonstrated with the minimum (critical wind velocity at ucr ~ 8 m/s for simulated system. Application of windbreak walls does not change the value of the critical wind velocity, but may improves performance of cooling unit at moderate and strong wind conditions. Simultaneous usage of windbreak walls and overshower deflectors may increase efficiency up to 20–30 % for the deflectors angle a = 60o. Simulation let one analyze aerodynamic patterns, induced inside cooling tower and homogeneity of velocities’ field in irrigator’s area.Presented results may be helpful for the CT aerodynamic design optimization, particularly, for perspective hybrid type CTs.

  7. Prevalence of Legionella strains in cooling towers and legionellosis cases in New Zealand.

    Lau, Robert; Maqsood, Saadia; Harte, David; Caughley, Brian; Deacon, Rob


    Over 3,900 water samples from 688 cooling towers were tested for Legionella in 2008 in New Zealand. Of 80 (2.05% isolation rate) Legionella isolates, 10 (12.5%) were L. pneumophila serogroup 1; 10 (12.5%) were L. anisa; nine (11.2%) were L. pneumophila serogroup 8; and one (1.2%) was L. longbeachae serogroup 2. Forty-one (51.2%) Legionella isolates were L. pneumophila serogroups. Over 3,990 water samples from 606 cooling towers were tested for Legionella in 2009 in New Zealand. Of 51 (1.28% isolation rate) Legionella isolates, 18 (35.3%) were L. pneumophila serogroup 1, and 39 (76.4%) were other L. pneumophila serogroups. L. pneumophila serogroups were significantly associated with legionellosis cases in 2008 and 2009. L. longbeachae serogroups were equally significantly associated with legionellosis cases. This significant association of L. longbeachae with legionellosis particularly of L. longbeachae serogroup 1 is unique in that part of the world. The authors' study also showed that the aqueous environment of the cooling tower is not a natural habitat for pathogenic L. longbeachae. Regular monitoring and maintenance of cooling towers have prevented outbreaks of legionellosis.

  8. Energy Efficient Electronics Cooling Project

    Steve O' Shaughnessey; Tim Louvar; Mike Trumbower; Jessica Hunnicutt; Neil Myers


    Parker Precision Cooling Business Unit was awarded a Department of Energy grant (DE-EE0000412) to support the DOE-ITP goal of reducing industrial energy intensity and GHG emissions. The project proposed by Precision Cooling was to accelerate the development of a cooling technology for high heat generating electronics components. These components are specifically related to power electronics found in power drives focused on the inverter, converter and transformer modules. The proposed cooling system was expected to simultaneously remove heat from all three of the major modules listed above, while remaining dielectric under all operating conditions. Development of the cooling system to meet specific customer's requirements and constraints not only required a robust system design, but also new components to support long system functionality. Components requiring further development and testing during this project included pumps, fluid couplings, cold plates and condensers. All four of these major categories of components are required in every Precision Cooling system. Not only was design a key area of focus, but the process for manufacturing these components had to be determined and proven through the system development.

  9. Coupling model and solving approach for performance evaluation of natural draft counter-flow wet cooling towers

    Wang Wei


    Full Text Available When searching for the optimum condenser cooling water flow in a thermal power plant with natural draft cooling towers, it is essential to evaluate the outlet water temperature of cooling towers when the cooling water flow and inlet water temperature change. However, the air outlet temperature and tower draft or inlet air velocity are strongly coupled for natural draft cooling towers. Traditional methods, such as trial and error method, graphic method and iterative methods are not simple and efficient enough to be used for plant practice. In this paper, we combine Merkel equation with draft equation, and develop the coupled description for performance evaluation of natural draft cooling towers. This model contains two inputs: the cooling water flow, the inlet cooling water temperature and two outputs: the outlet water temperature, the inlet air velocity, equivalent to tower draft. In this model, we furthermore put forward a soft-sensing algorithm to calculate the total drag coefficient instead of empirical correlations. Finally, we design an iterative approach to solve this coupling model, and illustrate three cases to prove that the coupling model and solving approach proposed in our paper are effective for cooling tower performance evaluation.

  10. Study the factors on which efficiency of cooling tower can be critically acclaimed (A case Study

    Krishna S. Vishwakarma


    Full Text Available Water cooling is widely used in many industrial processes to control heat removal from a hot material surface. In order to control the temperature distributions, a deeper understanding more accurate estimation of spray heat transfer rates is needed. In a new technique combining experiment and computational modeling developed for water cooling. It is better to understand the heat transfer mechanisms from the combustion gases to the cooling water and then from the cooling water to the environment. To meet this need a logic tree is developed to provide guidance on how to balance and identify problems within cooling system and schedule appropriate maintenance. Fluid dynamics, Thermodynamics and Heat transfer are involved in developing a cooling system model and the operation is familiar to the general operating companies. There will be the comparison and parametric investigation of the cooling system model in the logic tree and the results are summarized as tables and charts. The objective is to identify the several ways of improving efficiency of cooling tower. In this study we are doing the comparison ofsome calculations regarding the cooling tower.


    Smith, C.; Brigmon, R.


    Legionnaires disease is a pneumonia caused by the inhalation of the bacterium Legionella pneumophila. The majority of illnesses have been associated with cooling towers since these devices can harbor and disseminate the bacterium in the aerosolized mist generated by these systems. Historically, Savannah River Site (SRS) cooling towers have had occurrences of elevated levels of Legionella in all seasons of the year and in patterns that are difficult to predict. Since elevated Legionella in cooling tower water are a potential health concern a question has been raised as to the best control methodology. In this work we analyze available chemical, biological, and atmospheric data to determine the best method or key parameter for control. The SRS 4Q Industrial Hygiene Manual, 4Q-1203, 1 - G Cooling Tower Operation and the SRNL Legionella Sampling Program, states that 'Participation in the SRNL Legionella Sampling Program is MANDATORY for all operating cooling towers'. The resulting reports include L. pneumophila concentration information in cells/L. L. pneumophila concentrations >10{sup 7} cells/L are considered elevated and unsafe so action must be taken to reduce these densities. These remedial actions typically include increase biocide addition or 'shocking'. Sometimes additional actions are required if the problem persists including increase tower maintenance (e.g. cleaning). Evaluation of 14 SRS cooling towers, seven water quality parameters, and five Legionella serogroups over a three-plus year time frame demonstrated that cooling tower water Legionella densities varied widely though out this time period. In fact there was no one common consistent significant variable across all towers. The significant factors that did show up most frequently were related to suspended particulates, conductivity, pH, and dissolved oxygen, not chlorine or bromine as might be expected. Analyses of atmospheric data showed that there were more frequent significant

  12. Prevalence and Molecular Characteristics of Waterborne Pathogen Legionella in Industrial Cooling Tower Environments

    Lijie Li


    Full Text Available Cooling towers are a source of Legionnaires’ disease. It is important from a public health perspective to survey industrial cooling towers for the presence of Legionella. Prospective surveillance of the extent of Legionella pollution was conducted at factories in Shijiazhuang, China between March 2011 and September 2012. Overall, 35.7% of 255 industrial cooling tower water samples showed Legionella-positive, and their concentrations ranged from 100 Colony-Forming Units (CFU/liter to 88,000 CFU/liter, with an average concentration of 9100 CFU/liter. A total of 121 isolates were obtained. All isolates were L. pneumophila, and the isolated serogroups included serogroups 1 (68 isolates, 56.2%, 6 (25, 20.7%, 5 (12, 9.9%, 8 (8, 6.6%, 3 (6, 5.0% and 9 (2, 1.6%. All 121 isolates were analyzed by pulsed-field gel electrophoresis (PFGE and 64 different patterns were obtained. All 121 isolates were analyzed sequence-based typing (SBT, a full 7-allele profile was obtained from 117 isolates. One hundred and seventeen isolates were divided into 49 sequence types. Two virulence genes, lvh and rtxA, are analyzed by polymerase chain reaction (PCR. 92.6% (112/121 and 98.3% (119/121 isolates carried lvh and rtxA respectively and 90.9% (110/121 of tested isolates carried both genes. Our results demonstrated high prevalence and genetic polymorphism of L. pneumophila in industrial cooling tower environments in Shijiazhang, China, and the SBT and virulence gene PCR results suggested that the isolates were pathogenic. Improved control and prevention strategies are urgently needed.

  13. Reduction of Fire Hazard in Materials for Irrigators and Water Collectors in Cooling Towers

    Smirnov, N. V.; Konstantinova, N. I., E-mail: [FGBU VNIIPO of EMERCOM of Russia (All-Russian Scientific-research Institute of Fire Protection) (Russian Federation); Gordon, E. P. [Research and Production Center “Kaustik” (Russian Federation); Poedintsev, E. A. [FGBU VNIIPO of EMERCOM of Russia (All-Russian Scientific-research Institute of Fire Protection) (Russian Federation)


    A way of reducing the fire hazard of PVC film used to make cooling-tower irrigators and water collectors is examined. A new generation of fire retardant, nanostructured magnesium hydroxide, is used to impart fire retardant properties. The fabrication technology is optimized with a roller-calendering manufacturing technique, and the permissible ranges of fire hazard indicators for materials in irrigators and water collectors are determined.

  14. Cooling tower for the cooling water that drains from the condensor of a steam generator or the condensors of a plurality of steam generators

    Jorzyk, S.; Scholl, G.; Hoelter, H.; Igelbuescher, H.; Gresch, H.; Dewert, H.


    This invention relates to a cooling tower for the cooling water that drains from the condenser of a steam generator or from the condensers of a plurality of steam generators. The tower is fitted with large-area inserts and these form a heat-exchange area into which the cooling water is passed. A rising flow of air passes through this zone in counterflow to the cooling water. The cooling tower is provided with a smoke-gas feed to introduce cleaned, preferably wet-cleaned, smoke gas into the flow of cooling air, which is connected to a plurality of gas outlet pipes. The outlet cross-sections of those pipes open out into the cooling tower above the heat-exchange zone. In order to improve the introduction of the cleaned smoke gases into the flow of cooling air within a cooling tower, this invention proposes that rotors be provided in the gas outlet pipes in the area of their outlet cross-sections. To this end, it is also possible to make each gas outlet pipe rotatable about its longitudinal axis, the angle of inclination of the gas outlet pipes being variable.

  15. Optimization of mechanical draft counter flow wet-cooling tower using artificial bee colony algorithm

    Rao, R.V., E-mail: [S.V. National Institute of Technology, Surat, Gujarat State 395 007 (India); Patel, V.K. [S.V. National Institute of Technology, Surat, Gujarat State 395 007 (India)


    Research highlights: {yields} ABC algorithm is used for optimization of counter flow wet-cooling tower. {yields} Minimizing the total annual cost for specific heat duty is the objective function. {yields} Six examples are presented to demonstrate the effectiveness of the proposed algorithm. {yields} The results are compared with the results of GAMS optimization package. {yields} The ABC algorithm can be modified to suit optimization of other thermal systems. -- Abstract: This study explores the use of artificial bee colony (ABC) algorithm for design optimization of mechanical draft counter flow wet-cooling tower. Minimizing the total annual cost for specific heat duty requirement is considered as objective function. Three design variables such as water to air mass ratio, mass velocity of water and mass velocity of air are considered for optimization. Evaluations of the cooling tower geometry and performances are based on an adaptive version of Merkel's method. Temperature and enthalpy constraints are included in the optimization procedure. Six examples are presented to demonstrate the effectiveness and accuracy of the proposed algorithm. The results of optimization using ABC are validated by comparing with those obtained by using GAMS optimization package. The effect of variation of ABC parameters on the convergence and optimum value of the objective function has also been presented.


    A Haddad


    Full Text Available Cooling towers are extensively used to evacuate large quantities of heat at modest temperatures through a change of phase of the flowing cooling fluid. Based on this classical principle, the present study investigates the influence of salty water on the heat exchange produced. For that purpose, experiments are carried out using fresh and salty water. Furthermore, a comparison with the results produced through an approach involving the solution of energy equation involving the flow of air on an evaporating film of fluid. The detailed results show a preponderance of fresh water over the salty.


    WANG Kai; SUN Feng-zhong; ZHAO Yuan-bin; GAO Ming; SHI Yue-tao


    A model for heat and mass transfer in a natural-draft wet cooling tower was established. Numerical simulation with the k-ε turbulent model was conducted. Distribution rules of air inlet aerodynamic field were studied. Field experiments were done in a cooling tower in power plant, and the test data was compared with the related results. The definition of characteristic air velocity was proposed and its influencing factors, such as the cross-wind velocity and circumferential angle, were quantitatively studied. It can be used to evaluate the performance of cooling tower and to calculate the ventilation quantity and resistance of air inlet. It is also a theoretical basis for cooling tower design and performance optimization.

  18. Prediction of ground vibration due to the collapse of a 235 m high cooling tower under accidental loads

    Lin, Feng; Li, Yi [Department of Building Engineering, Tongji University, No. 1239 Siping Road, Shanghai 200092 (China); Gu, Xianglin, E-mail: [Department of Building Engineering, Tongji University, No. 1239 Siping Road, Shanghai 200092 (China); Zhao, Xinyuan [Department of Building Engineering, Tongji University, No. 1239 Siping Road, Shanghai 200092 (China); Tang, Dongsheng [Guangdong Electric Power Design Institute, No. 1 Tianfeng Road, Guangzhou, Guangdong 510663 (China)


    Highlights: ► Ground vibration due to the collapse of a huge cooling tower was predicted. ► Accidental loads with different characteristics caused different collapse modes. ► Effect of ground vibration on the nuclear-related facilities cannot be ignored. -- Abstract: A comprehensive approach is presented in this study for the prediction of the ground vibration due to the collapse of a 235 m high cooling tower, which can be caused by various accidental loads, e.g., explosion or strong wind. The predicted ground motion is to be used in the safety evaluation of nuclear-related facilities adjacent to the cooling tower, as well as the plant planning of a nuclear power station to be constructed in China. Firstly, falling weight tests were conducted at a construction site using the dynamic compaction method. The ground vibrations were measured in the form of acceleration time history. A finite element method based “falling weight-soil” model was then developed and verified by field test results. Meanwhile, the simulated collapse processes of the cooling tower under two accidental loads were completed in a parallel study, the results of which are briefly introduced in this paper. Furthermore, based on the “falling weight-soil” model, “cooling tower-soil” models were developed for the prediction of the ground vibrations induced by two collapse modes of the cooling tower. Finally, for a deep understanding of the vibration characteristics, a parametric study was also conducted with consideration of different collapse profiles, soil geologies as well as the arrangements of an isolation trench. It was found that severe ground vibration occurred in the vicinity of the cooling tower when the collapse happened. However, the vibration attenuated rapidly with the increase in distance from the cooling tower. Moreover, the “collapse in integrity” mode and the rock foundation contributed to exciting intense ground vibration. By appropriately arranging an isolation

  19. Comprehensive study of drift from mechanical draft cooling towers. Final report

    Laulainen, N.S.; Webb, R.O.; Wilber, K.R.; Ulanski, S.L.


    Drift from mechanical draft cooling towers was studied to establish a data base for use in drift deposition model validation. This objective was met by the simultaneous measurement of cooling tower source emission parameters, meteorological variables and drift deposition patterns during seven of eight test runs. Results from six of these test runs are presented and discussed. Source characterization measurements were made of cooling tower emission parameters such as updraft velocity and temperature profiles, liquid and mineral mass drift emission rates, and drift droplet size distributions. The meteorological measurements included wet- and dry-bulb temperature and wind speed and direction at various heights to provide information on the vertical structure of temperature, moisture and mass transport. Surface deposition measurements included both droplet and bulk mineral mass deposition rates. Substantial variation in drift emissions were noticed. Large day-to-day variations for a given cell and large cell-to-cell variations were observed. The problem of deriving a total droplet emission spectrum and rate from one or two towers is complicated and the modeler must decide on the amount of detail he needs to satisfactorily predict downwind deposition patterns. Meteorological conditions during the drift study were characterized by relatively high winds, warm temperatures and moderate humidities. The relatively high winds increased the uncertainty in the measured deposition patterns. In spite of the large (factor of 2 or 3) uncertainty in the measured deposition rates, preliminary calculations of drift deposition rates are in agreement with each other for test run 1. Although the present study did not meet all the requirements for complete validation of various drift models, it has contributed a unique set of data for that purpose.

  20. Knowledge base for the systematic design of wet cooling towers. Pt. 2: Fill and other design parameters

    Mohiuddin, A.K.M. [Bangladesh Inst. of Technology, Dhaka (Bangladesh). Dept. of Mechanical Engineering; Kant, K. [Indian Inst. of Tech., Kanpur (India). Dept. of Mechanical Engineering and Nuclear Centre


    This paper describes the final part of the detailed methodology for the thermal design of wet, counterflow and crossflow types of mechanical and natural draught cooling towers. This part includes the following design steps: the fill or packing, total packed height and the number of decks, water and air loading, pressure drop across the packing, natural draught tower, fan design for a mechanical draught cooling tower, blowdown and make-up water rate, water distribution systems and drift eliminators. Different empirical relations and assumptions are used in this part of the design procedure. (author)

  1. Investigation of Microbial Respirometry for Monitoring Natural Sulfide Abatement in Geothermal Cooling Tower Basins

    Peter A. Pryfogle


    Geothermal plant operators are interested in investigating the ability of micro-organisms found in the cooling tower basin to metabolize and cycle sulfide to less toxic sulfur compounds. If the growth or activity of the organisms participating in sulfur-oxidation could be selectively enhanced, then hydrogen sulfide could be naturally abated in the cooling basin, substantially reducing the costs associated with the chemicals used for abatement. The use of respirometry has been proposed as a technique for monitoring the response of the microbial populations found in geothermal cooling towers to various conditions, including the addition of nutrients such as nitrogen and phosphorus. Respiro-metry is a manometric measurement of dissolved gases that are in equilibrium in a con-fined sample volume. Since microbes expire varying amounts of carbon dioxide or oxygen as they metabolize nutrients, this technique can be used to evaluate their activities in process streams. This report describes a series of experiments designed to determine the suitability of respirometry for tracking microbial activity for evaluating and enhancing natural abatement processes in geothermal cooling basins.

  2. Comparison of the efficacy of free residual chlorine and monochloramine against biofilms in model and full scale cooling towers.

    Türetgen, Irfan


    The presence of microbial cells on surfaces results in the formation of biofilms, which may also give rise to microbiologically influenced corrosion. Biofilms accumulate on all submerged industrial and environmental surfaces. The efficacy of disinfectants is usually evaluated using planktonic cultures, which often leads to an underestimate of the concentration required to control a biofilm. The aim of this study was to investigate the efficacy of monochloramine on biofilms developed in a cooling tower. The disinfectants selected for the study were commercial formulations recommended for controlling microbial growth in cooling towers. A cooling tower and a laboratory model recirculating water system were used as biofilm reactors. Although previous studies have evaluated the efficacy of free chlorine and monochloramine for controlling biofilm growth, there is a lack of published data concerning the use monochloramine in cooling towers. Stainless steel coupons were inserted in each tower basin for a period of 30 d before removal. Monochloramine and free chlorine were tested under identical conditions on mixed biofilms which had been allowed to grow on coupons. Monochloramine was found to be significantly more effective than free chlorine against cooling tower biofilms.

  3. Technology to Facilitate the Use of Impaired Waters in Cooling Towers

    Colborn, Robert


    The project goal was to develop an effective silica removal technology and couple that with existing electro-dialysis reversal (EDR) technology to achieve a cost effective treatment for impaired waters to allow for their use in the cooling towers of coal fired power plants. A quantitative target of the program was a 50% reduction in the fresh water withdrawal at a levelized cost of water of $3.90/Kgal. Over the course of the program, a new molybdenum-modified alumina was developed that significantly outperforms existing alumina materials in silica removal both kinetically and thermodynamically. The Langmuir capacity is 0.11g silica/g adsorbent. Moreover, a low cost recycle/regeneration process was discovered to allow for multiple recycles with minimal loss in activity. On the lab scale, five runs were carried out with no drop in performance between the second and fifth run in ability to absorb the silica from water. The Mo-modified alumina was successfully prepared on a multiple kilogram scale and a bench scale model column was used to remove 100 ppm of silica from 400 liters of simulated impaired water. Significant water savings would result from such a process and the regeneration process could be further optimized to reduce water requirements. Current barriers to implementation are the base cost of the adsorbent material and the fine powder form that would lead to back pressure on a large column. If mesoporous materials become more commonly used in other areas and the price drops from volume and process improvements, then our material would also lower in price because the amount of molybdenum needed is low and no additional processing is required. There may well be engineering solutions to the fine powder issue; in a simple concept experiment, we were able to pelletize our material with Boehmite, but lost performance due to a dramatic decrease in surface area.

  4. NPP planning based on analysis of ground vibration caused by collapse of large-scale cooling towers

    Lin, Feng; Ji, Hongkui [Department of Structural Engineering, Tongji University, No. 1239 Siping Road, Shanghai 200092 (China); Gu, Xianglin, E-mail: [Department of Structural Engineering, Tongji University, No. 1239 Siping Road, Shanghai 200092 (China); Li, Yi [Department of Structural Engineering, Tongji University, No. 1239 Siping Road, Shanghai 200092 (China); Wang, Mingreng; Lin, Tao [East China Electric Power Design Institute Co., Ltd, No. 409 Wuning Road, Shanghai 200063 (China)


    Highlights: • New recommendations for NPP planning were addressed taking into account collapse-induced ground vibration. • Critical factors influencing the collapse-induced ground vibration were investigated. • Comprehensive approach was presented to describe the initiation and propagation of collapse-induced disaster. - Abstract: Ground vibration induced by collapse of large-scale cooling towers can detrimentally influence the safe operation of adjacent nuclear-related facilities. To prevent and mitigate these hazards, new planning methods for nuclear power plants (NPPs) were studied considering the influence of these hazards. First, a “cooling tower-soil” model was developed, verified, and used as a numerical means to investigate ground vibration. Afterwards, five critical factors influencing collapse-induced ground vibration were analyzed in-depth. These influencing factors included the height and weight of the towers, accidental loads, soil properties, overlying soil, and isolation trench. Finally, recommendations relating to the control and mitigation of collapse-induced ground vibration in NPP planning were proposed, which addressed five issues, i.e., appropriate spacing between a cooling tower and the nuclear island, control of collapse modes, sitting of a cooling tower and the nuclear island, application of vibration reduction techniques, and the influence of tower collapse on surroundings.

  5. Measures for noise pollution abatement in existing cooling tower systems; Massnahmen zur Geraeuschminderung an bestehenden Kuehlturmanlagen

    Niessen, R. [Sulzer-Escher Wyss GmbH, Lindau (Germany)


    The operator`s order discussed by the paper was for planning and performance of backfitting measures for noise pollution abatement in an existing cooling tower system equipped with sound attenuation devices. Although the existing plant was operating in compliance with the legal noise emission limits, residents of neighbouring dwellings had been complaining about noise pollution. (orig./CB) [Deutsch] Die Aufgabe, eine nachtraegliche Massnahme zur Laermminderung an einer bestehenden, mit Schalldaempfern ausgeruesteten Anlage zu planen und durchzufuehren, wurde vom Betreiber einer Rueckkuehlanlage gestellt. Der vom Gesetzgeber definierte Grenzwert fuer den Nachtbetrieb wurde mit der bestehenden Anlage zwar erreicht, doch die Anwohner fuehlten eine Belaestigung durch den Anlagenbetrieb. (orig./GL)

  6. Reinforced concrete corrosion: Application of Bayesian networks to the risk management of a cooling tower

    Capra, B.; Le Drogo, J.; Wolff, V.


    Degradation modelling of concrete structures uses uncertain variables and leads, using reliability assessment, to time dependant evolution of failure probabilities. However, only few data are generally available to feed models leading to two types of uncertainties: an intrinsic one depending on the modelled phenomena and one related to the precision of the measurement. Each new data available is a piece of information which allows to update the initial prediction. In this article, an example of updating process, based on a Bayesian network, is presented and applied on the corrosion risk of a cooling tower.

  7. Reinforced concrete corrosion: Application of Bayesian networks to the risk management of a cooling tower

    Capra, B.; Le Drogo, J.; Wolff, V. [OXAND S.A., 36 bis avenue F. Roosevelt, 77210 Avon (France)


    Degradation modelling of concrete structures uses uncertain variables and leads, using reliability assessment, to time dependant evolution of failure probabilities. However, only few data are generally available to feed models leading to two types of uncertainties: an intrinsic one depending on the modelled phenomena and one related to the precision of the measurement. Each new data available is a piece of information which allows to update the initial prediction. In this article, an example of updating process, based on a Bayesian network, is presented and applied on the corrosion risk of a cooling tower. (authors)

  8. Synthesis of some novel sulfonamide derivatives and investigating their biocidal activity in cooling towers

    Badawi, Abdelfattah M.; Mohamed, Dalia Emam; Hafiz, Amal A.; Amed, Sahar M. [Egyptian Petroleum Research Institute (EPRI), Nasr City, Cairo (Egypt). Applied Surfactants Lab.; Gohar, Yousry M. [Alexandria Univ. (Egypt). Microbiology Div.; Soliman, El-Sayed Ahmed [Ain Shams Univ., Cairo (Egypt). Chemistry Dept.; Sanan, Mohamed S. [Alexandria National Refining and Petrochemical Co. (ANRPC), Alexandria (Egypt)


    A novel series of dibenzothiophenedioxide sulphonamide derivatives were synthesized and tested as antimicrobial agents. The chemical structures of the prepared compounds were confirmed by micro elemental analysis, fourier transform infrared (FT-IR) and proton nuclear magnetic resonance spectroscopy (H-NMR). The surface parameters of two of the prepared compounds were determined at 35 C including, surface tension, effectiveness, maximum surface excess and minimum surface area. Also the standard free energy of micellization and adsorption were recorded. The results showed that the prepared sulphonamides have good surface properties and effective antimicrobial activity against thirty three test organisms isolated from cooling towers. (orig.)

  9. Energy saving modification for cooling tower by using water turbine%利用水轮机对冷却塔进行节能改造



    This paper explains the energy saving principles and advantages of electric fan of large scale cooling tower,and introduces the design procedure,modification project,data calculation and analysis,and energy saving calculation as well as static payback time of mixed flow water turbine special for cooling tower instead of motor. After modification,energy-saving purpose is achieved.%阐述了大型冷却塔电动风机节能改造的原理和优点,介绍了以冷却塔专用混流式水轮机取代电机的设计过程、改造工程、数据计算及分析、节能计算、静态投资回收期等,改造后达到了节能目的。

  10. Experimental analysis of heat and mass transfer phenomena in a direct contact evaporative cooling tower

    Lemouari, M. [Department of Processes Engineering, Faculty of Sciences and Engineering, University of Bejaia (Algeria); Boumaza, M. [Department of Chemical Engineering, College of Engineering - King Saud University, P.O. Box 800, Riyadh (Saudi Arabia); Kaabi, A. [Department of Genie Climatique, Faculty of Engineering, University of Constantine, Constantine (Algeria)


    This paper deals with an experimental analysis of simultaneous heat and mass transfer phenomena between water and air by direct contact in a packed cooling tower. The tower is filled with a ''VGA.'' (Vertical Grid Apparatus) type packing. The packing is 0.42 m high and consists of four (04) galvanised sheets having a zigzag form, between which are disposed three (03) metallic vertical grids in parallel with a cross-sectional test area of 0.15 m x 0.148 m. This study investigates the effect of the air and water flow rates on the global heat and mass transfer coefficient as well as the evaporation rate of water into the air stream, for different inlet water temperatures. Two operating regimes were observed during the air/water contact inside the tower, a Pellicular Regime (PR) and a Bubble and Dispersion Regime (BDR). These two regimes can determine the best way to promote the heat and mass transfer phenomena in such device. The BDR regime seems to be more efficient than the Pellicular Regime, as it enables to achieve relatively higher values of the global heat and mass transfer coefficient and larger water evaporation rates. The comparison between the obtained results and some of those available in the literature for other types of packing indicates that this type possesses good heat and mass transfer characteristics. (author)

  11. A Large Community Outbreak of Legionnaires' Disease Associated With a Cooling Tower in New York City, 2015.

    Weiss, Don; Boyd, Christopher; Rakeman, Jennifer L; Greene, Sharon K; Fitzhenry, Robert; McProud, Trevor; Musser, Kimberlee; Huang, Li; Kornblum, John; Nazarian, Elizabeth J; Fine, Annie D; Braunstein, Sarah L; Kass, Daniel; Landman, Keren; Lapierre, Pascal; Hughes, Scott; Tran, Anthony; Taylor, Jill; Baker, Deborah; Jones, Lucretia; Kornstein, Laura; Liu, Boning; Perez, Rodolfo; Lucero, David E; Peterson, Eric; Benowitz, Isaac; Lee, Kristen F; Ngai, Stephanie; Stripling, Mitch; Varma, Jay K

    Infections caused by Legionella are the leading cause of waterborne disease outbreaks in the United States. We investigated a large outbreak of Legionnaires' disease in New York City in summer 2015 to characterize patients, risk factors for mortality, and environmental exposures. We defined cases as patients with pneumonia and laboratory evidence of Legionella infection from July 2 through August 3, 2015, and with a history of residing in or visiting 1 of several South Bronx neighborhoods of New York City. We describe the epidemiologic, environmental, and laboratory investigation that identified the source of the outbreak. We identified 138 patients with outbreak-related Legionnaires' disease, 16 of whom died. The median age of patients was 55. A total of 107 patients had a chronic health condition, including 43 with diabetes, 40 with alcoholism, and 24 with HIV infection. We tested 55 cooling towers for Legionella, and 2 had a strain indistinguishable by pulsed-field gel electrophoresis from 26 patient isolates. Whole-genome sequencing and epidemiologic evidence implicated 1 cooling tower as the source of the outbreak. A large outbreak of Legionnaires' disease caused by a cooling tower occurred in a medically vulnerable community. The outbreak prompted enactment of a new city law on the operation and maintenance of cooling towers. Ongoing surveillance and evaluation of cooling tower process controls will determine if the new law reduces the incidence of Legionnaires' disease in New York City.

  12. Effects of FLONLIZER, ultraviolet sterilizer, on Legionella species inhabiting cooling tower water.

    Yamamoto, H; Urakami, I; Nakano, K; Ikedo, M; Yabuuchi, E


    Legionella pneumophila in sterile distilled water was not detected after ultraviolet irradiation by FLONLIZER, a new-type sterilizer, at a flow rate of 82.5 to 364.8 liters/hr. When irradiated by FLONLIZER at a flow rate of under 324.0 liters/hr, no viable cells of legionellae, other heterotrophic bacteria and bacterivorous protozoa were detected in the cooling tower water, which was found to contain L. pneumophila. No viable cells of L. pneumophila and L. bozemanii suspended in sterile distilled water were detected after the irradiation with UV-doses of over 6.16 X 10(3) micro W.sec/cm2. At the irradiation of low UV-doses under 1.06 X 10(4) micro W.sec/cm2, the viable count of legionellae recuperated by photoreactivation from UV-damage increased with the exposure time under a white fluorescent lamp. However, in the samples irradiated with UV-doses of over 3.52 X 10(4) micro W.sec/cm2, equal to the FLONLIZER, legionellae did not recuperate even after 18 hr illumination with a white fluorescent lamp. FLONLIZER is thus expected to act as a sterilizer which can control the legionellae inhabiting cooling tower systems placed in outdoor space.

  13. Cleaning device for cooling elements of a dry cooling tower consisting of finned tubes

    Kelp, F.


    A nozzle housing is set on to the cooling elements which is equipped with intermediate walls as air guides. A compressed air connection and a suction air connection can be moved vertically in the nozzle housing by a transport spindle. There is a measuring device for dust loading between the two connections.

  14. Mathematical and experimental investigations on dispersion and recirculation of plumes from dry cooling towers at Wyodak Power Plant in Wyoming

    Onishi, Y.; Trent, D.S.


    The study presented was conducted (1) to develop a two-dimensional mathematical simulation model for determination of plume dispersion and recirculation from an existing code; (2) to investigate experimentally and mathematically the recirculation and temperature distributions of plumes from two dry cooling towers at the Wyodak Plant in Wyoming; and (3) to elucidate the effects of wind velocity, temperature of heated effluent, adjacent cooling towers and local topography on plume dispersion and recirculation. The mathematical model is based on solution of the steady flow momentum and energy equations using the stream function-vorticity technique. Experiments were conducted in a 10-foot-wide hydraulic flume, using water as a model flow. The study shows that plume recirculation and dispersion are strongly influenced by local topography and nearby structures such as adjacent cooling towers and buildings, as well as by the ambient wind velocity and effluent exit temperature.

  15. Molecular characterization of viable Legionella spp. in cooling tower water samples by combined use of ethidium monoazide and PCR.

    Inoue, Hiroaki; Fujimura, Reiko; Agata, Kunio; Ohta, Hiroyuki


    Viable Legionella spp. in environmental water samples were characterized phylogenetically by a clone library analysis combining the use of ethidium monoazide and quantitative PCR. To examine the diversity of Legionella spp., six cooling tower water samples and three bath water samples were collected and analyzed. A total of 617 clones were analyzed for their 16S rRNA gene sequences and classified into 99 operational taxonomic units (OTUs). The majority of OTUs were not clustered with currently described Legionella spp., suggesting the wide diversity of not-yet-cultured Legionella groups harbored in cooling tower water environments.

  16. Energy Conservation Applications of Cooling Towers of Telecom Air-Conditions%电信空调冷却塔供冷系统节能应用

    吴捷; 杨志昆; 曹业玲


    Based on the features of air conditioning load of telecommunications engine room, a indirect free cooling air conditioning system, which contains cooling tower and plate heat exchange, is chosen to provide cold for telecommunications engine room in winter and part of the transition seasons. Firstly the affirmance of room air-conditioning supply air temperature in winter and cooling temperature of the cooling tower are introduced. Then the influence of cooling temperature to the operating power of the cooling tower is analyzed. After that the running time and energy saving effects of cooling tower for free cooling are roughly estimated. And the concept of cooling load demand and supply index is introduced. The three factors affecting the index in the second pivot project of Jiangsu Telecom are measured. At last the free refrigeration technology and the potential energy savings of Jiangsu Telecom are summarized.%根据电信机楼的空调负荷特点,在冬季和部分过渡季节,选择使用冷却塔加板式换热器的间接式免费供冷空调系统为电信机楼提供冷量。介绍了冬季机房空调送风温度和冷却塔供冷温度的确定,分析了冷却塔供冷温度对冷却塔运行消耗的影响。通过预测计算确定冷却塔免费制冷的的运行时间及节能效果。并引入了冷负荷供需指数的概念,经过现场测试计算得出江苏电信第二枢纽工程中影响该指数的三个因素,最后总结了江苏电信免费制冷技术的节能情况和应用潜力。

  17. Cooled Ceramic Turbine Vane Project

    National Aeronautics and Space Administration — N&R Engineering will investigate the feasibility of cooled ceramics, such as ceramic matrix composite (CMC) turbine blade concepts that can decrease specific...

  18. Thermal Performance for Wet Cooling Tower with Different Layout Patterns of Fillings under Typical Crosswind Conditions

    Ming Gao


    Full Text Available A thermal-state model experimental study was performed in lab to investigate the thermal performance of a wet cooling tower with different kinds of filling layout patterns under windless and 0.4 m/s crosswind conditions. In this paper, the contrast analysis was focused on comparing a uniform layout pattern and one kind of optimal non-uniform layout pattern when the environmental crosswind speed is 0 m/s and 0.4 m/s. The experimental results proved that under windless conditions, the heat transfer coefficient and total heat rejection of circulating water for the optimal non-uniform layout pattern can enhance by approximately 40% and 28%, respectively, compared with the uniform layout pattern. It was also discovered that the optimal non-uniform pattern can dramatically relieve the influence of crosswind on the thermal performance of the tower when the crosswind speed is equal to 0.4 m/s. For the uniform layout pattern, the heat transfer coefficient under 0.4 m/s crosswind conditions decreased by 9.5% compared with the windless conditions, while that value lowered only by 2.0% for the optimal non-uniform layout pattern. It has been demonstrated that the optimal non-uniform layout pattern has the better thermal performance under 0.4 m/s crosswind condition.

  19. Application of a semi-spectral cloud water parameterization to cooling tower plumes simulations

    Bouzereau, Emmanuel; Musson Genon, Luc; Carissimo, Bertrand


    In order to simulate the plume produced by large natural draft cooling towers, a semi-spectral warm cloud parameterization has been implemented in an anelastic and non-hydrostatic 3D micro-scale meteorological code. The model results are compared to observations from a detailed field experiment carried out in 1980 at Bugey (location of an electrical nuclear power plant in the Rhône valley in East Central France) including airborne dynamical and microphysical measurements. Although we observe a slight overestimation of the liquid-water content, the results are satisfactory for all the 15 different cases simulated, which include different meteorological conditions ranging from low wind speed and convective conditions in clear sky to high wind and very cloudy. Such parameterization, which includes semi-spectral determination for droplet spectra, seems to be promising to describe plume interaction with atmosphere especially for aerosols and cloud droplets.

  20. Research on Cooling Tower Prevent Ice Technology%冷却塔的防冰技术研究



    Cooling tower cooling tower blinds icing is north universal existence question,shutter freeze effects of tower cooling effect,increase the structural load,reduces the life of the structure,destruction of cooling tower packing,the inevitable result of the cooling efficiency to reduce,increase the transformation frequency caused by ice,high energy consumption,fan fault frequently.Based on the cause analysis of cooling tower icing and deicing solutions feasibility study,and study out the specific solutions,and applied to practical,achieved good results and economic benefits,use of chemical ice technology to solve the northern winter blinds icing problems.%冷却塔的百叶窗结冰是北方冷却塔普遍存在的问题。百叶窗结冰会影响塔的冷却效果,增加结构负荷,降低结构的使用寿命,破坏冷却塔的填料,不可避免地造成冷却效率降低,增加反转化冰的频率,造成能耗高、风机故障频繁。通过对冷却塔结冰原因的分析和防冰解决方案的可行性研究,给出了具体解决方案,并应用于实际,取得良好的效果和经济效益。利用该防冰技术可以有效解决冬季北方百叶窗结冰的难题。

  1. Free-living amoebae and their associated bacteria in Austrian cooling towers: a 1-year routine screening.

    Scheikl, Ute; Tsao, Han-Fei; Horn, Matthias; Indra, Alexander; Walochnik, Julia


    Free-living amoebae (FLA) are widely spread in the environment and known to cause rare but often serious infections. Besides this, FLA may serve as vehicles for bacterial pathogens. In particular, Legionella pneumophila is known to replicate within FLA thereby also gaining enhanced infectivity. Cooling towers have been the source of outbreaks of Legionnaires' disease in the past and are thus usually screened for legionellae on a routine basis, not considering, however, FLA and their vehicle function. The aim of this study was to incorporate a screening system for host amoebae into a Legionella routine screening. A new real-time PCR-based screening system for various groups of FLA was established. Three cooling towers were screened every 2 weeks over the period of 1 year for FLA and Legionella spp., by culture and molecular methods in parallel. Altogether, 83.3 % of the cooling tower samples were positive for FLA, Acanthamoeba being the dominating genus. Interestingly, 69.7 % of the cooling tower samples were not suitable for the standard Legionella screening due to their high organic burden. In the remaining samples, positivity for Legionella spp. was 25 % by culture, but overall positivity was 50 % by molecular methods. Several amoebal isolates revealed intracellular bacteria.

  2. Cooling Tower Optimization A Simple Way to Generate Green Megawatts and to Increase the Efficiency of a Power Plant

    Strohmer, F.


    The profitability of nuclear power plants is worldwide challenged by low electricity prices. One hand low cost shale gas is offering a low price electricity production , other hand additional taxes on fuel are reducing the operating income of nuclear power stations. The optimization of cooling towers can help to increase the efficiency and profit of a nuclear power plant. (Author)

  3. Tall towers for large wind turbines. Report from Vindforsk project V-342

    Engstroem, Staffan; Lyrner, Tomas; Hassanzadeh, Manouchehr; Stalin, Thomas; Johansson, John


    The general rule of thumb has been to furnish a wind turbine with a tower as tall as the turbine diameter, with deviations downwards for high wind speed sites. In this report the statement is questioned, with special emphasis for wind turbines sited in forests. The aim of this project was to propose and calculate candidate types of tall towers for on-shore wind turbines in the 3 - 5 MW range, with special reference to siting in forests with a representative wind shear. During the project this scope has been more precisely defined to study 3 and 5 MW wind turbines with hub heights of 80 - 175 meters featuring the following tower solutions: 1. Steel shell tower designed in a conventional way with flanges and both longitudinal and transverse welds. 2. Steel shell tower with bolted friction joints only. 3. Concrete tower with pretensioned steel tendons. 4. Hybrid tower with a lower concrete part and an upper part built as a conventional steel shell. 5. Lattice tower. 6. Wooden tower. During the execution of the project the design of a total of 42 towers was outlined and calculated. Today the welded steel shell tower dominates the wind turbine market. Larger turbines and higher hub heights result in larger optimal tower base diameters. For the road transportation there are limitations due to bridges and other obstacles. In Sweden the limit for transports with special permits in general maximizes the diameter to 4,5 metres. To some extent it is still technically possible to build towers with a less than optimal diameter, but due to the high mass and the large wall thickness they tend to be uneconomical in comparison with other alternatives above a hub height of roughly 100 metres. In this report welded steel shell towers were outlined for 3 MW turbines up to a hub height of 150 metres whereas the limit for the 5 MW towers was 100 metres. When diameter restrictions tend to make welded towers uneconomical, the next logical choice is steel shell towers with bolted friction

  4. Effect of organic on chemical oxidation for biofouling control in pilot-scale seawater cooling towers

    Al-Bloushi, Mohammed


    Due to the scarcity of potable water in many regions of the world, the demand for seawater as an alternative evaporative cooling medium in cooling towers (CTs) has increased significantly in recent years. Seawater make-up in CTs is deemed the most feasible because of its unlimited supply in the coastal areas of Gulf and Red Sea. However, the seawater CTs have higher challenges greatly mitigating their performances because it is an open system where biofouling and bio-corrosion occurring within the fillers and piping of recirculation systems. Their pilot-scale CTs were constructed to assess the performance of three types of oxidizing biocides or oxidants, namely chlorine, chlorine dioxide (ClO2) and ozone, for biofouling control. The test results showed that the addition of organic (5mg/L of methanol (MeOH)) increased the bacterial growth in CT basin. All oxidants were effective in keeping the microbial growth to the minimum. Oxidation increased the oxidation-reduction potential (ORP) level from 270 to 600mV. Total residual oxidant (TRO) was increased with oxidation but it was slightly increased with organic addition. Other parameters including pH, dissolved oxygen (DO), conductivity levels were not changed. However, higher formation of disinfection by-products (DBPs) was detected with chlorination and ozonation. This indicates the organic level should be limited in the oxidation for biofouling control in seawater CTs.

  5. Driving gear for cooling towers - design, noise abatement, maintenance; Antriebssysteme fuer Kuehltuerme - Auslegung, Schallschutz, Instandhaltung

    Niestegge, J.; Plesser, J. [Flender (A.F.) und Co., Bocholt (Germany)


    Any optimal design of a cooling tower driving gear requires as precise as possible information on the operating conditions in practice. In addition, design engineers use verified data warranting reliable operation of the driving gears. From those data together with information on the specific operating environment and position in the cooling system, engineers derive the application-specific design data for the driving mechanisms, such as for instance special protective coatings, or specific bearing geometries. Other requirements considered include aspects of maintenance and noise abatement. (orig./CB) [Deutsch] Eine optimale Auslegung von Kuehlturmantrieben bedingt eine moeglichst exakte Angabe der Betriebsbedingungen. Darueber hinaus fliessen in die Auslegung Erfahrungswerte ein, die einen stoerungsfreien Betrieb der Getriebe gewaehrleisten. Mit diesen Daten und unter Beruecksichtigung des speziellen Aufstellortes ergibt sich ein kuehlturmspezifisches Getriebe, das z.B. durch den vergroesserten Lagerabstand oder durch die Sonderlackierung den Anforderungen im Kuehlturmbau in groesstmoeglicher Weise gerecht wird. Massgaben hinsichtlich der Wartungsfreundlichkeit und des Geraeuschverhaltens werden bei der Auslegung ebenfalls beruecksichtigt. (orig.)

  6. 4. Meeting on cooling towers. From practice - for practice; 4. Kuehlturm-Tagung. Aus der Praxis - Fuer die Praxis



    The 4th Cooling Tower meeting brought into focus aspects of economic efficiency of the water cooling system, i.e. the papers analyse investment cost and operating cost taking into account environmental policy and interests. Numerous examples from practice are discussed in the papers showing how wet cooling tower design and application-specific selection of design features can influence the performance of the entire system. (orig./CB) [Deutsch] Im Mittelpunkt der 4. Kuehlturm-Tagung steht die Wirtschaftlichkeit der Wasserrueckkuehlanlage, d.h. die Betrachtung der Investitions- und Betriebskosten unter Beruecksichtigung der Belange des Umweltschutzes. Mit Beispielen aus der Praxis zeigen die Referenten, wie sich die Auslegung und Auswahl eines Nasskuehlturms auf das Betriebsergebnis der Anlage auswirken. (orig./GL)

  7. Analysis of Free Cooling Technology by Using Cooling Tower%应用冷却塔免费供冷技术的特性分析

    徐欣; 杨木和


      对于单层面积大、内区房间多、冷负荷比较大的建筑,采用冷却塔免费供冷,既环保,又节能。本文以上海某集办公、酒店与商业为一体的玻璃幕墙建筑为研究对象,简要介绍了冷却塔免费供冷的原理与形式,通过对冷却塔免费供冷的分析与计算,确定了冷却塔过渡季节的供冷温度,并从空调机组送风温度、过渡季节冷负荷与夏季设计冷负荷之比、冷却塔供回水温差三个方面出发,研究其对冷却塔供水温度的影响,得出了一些有益的结论%  For the building with large single-floor area, many inner-rooms and high cooling-load, free cooling technology by using cooling tower is environment-protective and energy-saving. Based on a glass curtain wall building with offices, hotels and commercial rooms, the theory and form of free cooling system are introduced, and the supply cooling water temperature during transition season is determined by analysis and calculation. Three factors, including supply air temperature of air handling unit, ratio of cooling load of transition season to that of summer, and temperature difference of cooling tower supply and return water, which influence the cooling tower supply water temperature are studied. Some useful conclusions are obtained in this paper.


    符松; 翟志强


    This article reports the findings on the adverse effect of the crosswind on the performance of natural draft cooling towers through numerical computation with the k-ε eddy-viscosity turbulence model. It is observed here that the cause of the adverse effect of the crosswind on the cooling towers can be attributed to the around flow effect which destroys the radial inflow into the cooling towers when the wind is absent. Hence, a significant deterioration in the heat transfer from the heat exchangers at lateral sides occurs.


    Yu. A. Zenovich-Leshkevich-Olpinskiy


    Full Text Available The method of calculation of economic efficiency that can be universal and is suitable for feasibility study of modernization of irrigation and water distribution system of cooling towers has been developed. The method takes into account the effect of lower pressure exhaust steam in the condenser by lowering the temperature of the cooling water outlet of a cooling tower that aims at improvement of technical and economic indicators of heat power plants. The practical results of the modernization of irrigation and water distribution system of a cooling tower are presented. As a result, the application of new irrigation and water distribution systems of cooling towers will make it possible to increase the cooling efficiency by more than 4 оС and, therefore, to obtain the fuel savings by improving the vacuum in the turbine condensers. In addition, the available capacity of CHP in the summer period is increased. The results of the work, the experience of modernization of irrigation and water distribution systems of the Gomel CHP-2 cooling towers system, as well as the and methods of calculating of its efficiency can be disseminated for upgrading similar facilities at the power plants of the Belarusian energy system. Some measures are prosed to improve recycling systems, cooling towers and their structures; such measures might significantly improve the reliability and efficiency of technical water supply systems of heat power plants.


    Brigmon, R.; Leskinen, S.; Kearns, E.; Jones, W.; Miller, R.; Betivas, C.; Kingsley, M.; Lim, D.


    Detection of Legionella pneumophila in cooling towers and domestic hot water systems involves concentration by centrifugation or membrane filtration prior to inoculation onto growth media or analysis using techniques such as PCR or immunoassays. The Portable Multi-use Automated Concentration System (PMACS) was designed for concentrating microorganisms from large volumes of water in the field and was assessed for enhancing surveillance of L. pneumophila at the Savannah River Site, SC. PMACS samples (100 L; n = 28) were collected from six towers between August 2010 and April 2011 with grab samples (500 ml; n = 56) being collected before and after each PMACS sample. All samples were analyzed for the presence of L. pneumophila by direct fluorescence immunoassay (DFA) using FITC-labeled monoclonal antibodies targeting serogroups 1, 2, 4 and 6. QPCR was utilized for detection of Legionella spp. in the same samples. Counts of L. pneumophila from DFA and of Legionella spp. from qPCR were normalized to cells/L tower water. Concentrations were similar between grab and PMACS samples collected throughout the study by DFA analysis (P = 0.4461; repeated measures ANOVA). The same trend was observed with qPCR. However, PMACS concentration proved advantageous over membrane filtration by providing larger volume, more representative samples of the cooling tower environment, which led to reduced variability among sampling events and increasing the probability of detection of low level targets. These data highlight the utility of the PMACS for enhanced surveillance of L. pneumophila by providing improved sampling of the cooling tower environment.

  11. 我国冷却塔应用现状及面临的挑战%Applications and Challenges of Cooling Tower in Chin



    Cooling tower has been widely used in China. Cooling tower technology started late in China, but experienced rapid development. Several large-scale cooling towers, including natural draft counter-flow cooling tower, seawater cooling tower, tower with flue gas dispersion and indirect dry cooling tower, with nominated water spraying area up to 10,000m2 have been built around China. The large-scale natural draft counter-flow cooling tower for inland nuclear power has also been designing in China. In addition, natural cooling tower with water collecting system and cross flow cooling tower have also been used in small scale and scope. With the dramatic increasing of diameter and height of the cooling tower, how to design large-scale cooling towers with structural safety and high efficiency is the great technical challenge faced by domestic engineers, also creates opportunities for broad international cooperation.%冷却塔在我国火电厂的应用广泛。冷却塔技术在我国的应用起步较晚,但发展极为迅速,尤其是在逆流式通风冷却塔方面,先后建成投产的多座淋水面积超10000m2的超大型自然通风逆流塔(包括海水冷却塔、排烟冷却塔)和超大型间接空冷塔;在内陆核电站冷却塔应用方面,也开展了一系列研究和方案设计;此外,高位收水塔和横流塔方面也有小规模小范围的应用案例。随着冷却塔直径、高度的不断增加,冷却塔已变成火力发电厂内单体体量最大的构筑物,如何设计结构安全、运行安全、冷却效率高的大型冷却塔是我国工程师面临的技术挑战,也给广泛的国际合作创造了条件。

  12. The cool shopping centre of the Netherlands. The realization of four cooling units in Utrecht, Netherlands; Het koele winkelhart van Nederland. Realisatie vier koudecentrales in Utrecht



    A brief description is given of a project to install four cooling machines (absorption cooling, compression cooling, cooling towers, and water treatment units) in the office and shopping centre Hoog Catharijne in Utrecht, Netherlands. 3 ills., 1 tab.

  13. Isolation of Legionella pneumophila from cooling towers, public baths, hospitals, and fountains in Seoul, Korea, from 2010 to 2012.

    Kim, Changkyu; Jeon, Sujin; Jung, Jihun; Oh, Younghee; Kim, Yeonsun; Lee, Jaein; Choi, Sungmin; Chae, Youngzoo; Lee, Young-Ki


    Legionnaire's disease is associated with a high mortality rate. The authors collected 3,495 water samples in Seoul, Korea, between 2010 and 2012 from public facilities (cooling towers, public baths, hospitals, and decorative fountains), which are considered the major habitats of Legionella pneumophila. In all, 527 (15.1%) isolates of L. pneumophila were obtained by microbial culture and polymerase chain reaction. Serological diagnosis and pulsed-field gel electrophoresis (PFGE) analysis were performed for the samples. The authors categorized the samples into four groups (A-D) on the basis of PFGE results. The analysis revealed that cooling towers containing the most samples with L. pneumophila serogroup 1 constituted the highest proportion of isolate. Samples from public facilities and serogroups could be distinctively classified by PFGE patterns. Thus, it is expected that source-specific features revealed through PFGE and serological analyses could serve as the basis for effectively coping with future outbreaks of L. pneumophila.

  14. Optimization Design of Tower Type for Large Natural Draft Exhaust Smoke Cooling Tower%大型自然通风排烟冷却塔塔型优化设计

    万大伟; 王明韧


    在现有的规范规定条件下,本文以某1000MW火电机组为研究目标,开展湿式排烟冷却塔塔型优化工作。以塔高与塔底直径之比RAUZ、喉部直径与塔底直径之比RAUC、进风口高度塔底直径之比RAUL和填料高度RAUE作为塔型的主要变化参数,采用供水系统优化程序对湿式冷却塔进行选型分析。结果表明采用供水系统优化计算结合冷却塔塔型本体优化的选型方式,得到的冷却塔选型方案比较合理,满足工程实际需要,节约工程投资。%This article focuses on the optimization design of tower type for natural draft wet exhaust smoke cooling tower using optimization calculation methods based on a detailed research of typical 1000MW coal fired power units and existing design code. According to the main changes parameters of cooling tower including tower height and bottom diameter ratio、throat diameter and bottom diameter ratio、inlet height and bottom diameter ratio and fill height, the optimization calculation program of water supply system was used to decide the selection and economical allocation of cooling tower.The result shows that the dimension of the natural draft wet cooling tower is relatively more appropriate and practical when the cooling towers are selected using optimization calculation of water supply system and in combination with optimization design of cooling tower body.

  15. Project Profile: Hydrogen Fuel Cell Mobile Lighting Tower (HFCML)

    McLaughlin, Russell


    NASA is committed to finding innovative solutions that improve the operational performance of ground support equipment while providing environment and cost benefits, as well. Through the Hydrogen Fuel Cell Mobile Lighting Tower (HFCML) project, NASA gained operational exposure to a novel application of high efficiency technologies. Traditionally, outdoor lighting and auxiliary power at security gates, launch viewing sites, fallback areas, outage support, and special events is provided by diesel generators with metal halide lights. Diesel generators inherently contribute to C02, NOx, particulate emissions, and are very noisy. In 2010, engineers from NASA's Technology Evaluation for Environmental Risk Mitigation Principal Center (TEERM) introduced KSC operations to a novel technology for outdoor lighting needs. Developed by a team led by Sandia National Laboratory (SNL), the technology pairs a 5kW hydrogen fuel cell with robust high efficiency plasma lights in a towable trailer. Increased efficiency, in both the fuel cell power source and lighting load, yields longer run times between fueling operations while providing greater auxiliary power. Because of the unit's quiet operation and no exhaust fumes, it is capable of being used indoors and in emergency situations, and meets the needs of all other operational roles for metal halide/diesel generators. The only discharge is some water and warm air. Environmental benefits include elimination of diesel particulate emissions and estimated 73% greenhouse gas emissions savings when the hydrogen source is natural gas (per GREET model). As the technology matures the costs could become competitive for the fuel cell units which are approximately 5 times diesel units. Initial operational . concerns included the hydrogen storage tanks and valves, lightning safety/grounding, and required operating and refueling procedures. TEERM facilitated technical information exchange (design drawings, technical standards, and operations

  16. Legionella detection and subgrouping in water air-conditioning cooling tower systems in Kuwait.

    Al-Matawah, Qadreyah; Al-Zenki, Sameer; Al-Azmi, Ahmad; Al-Waalan, Tahani; Al-Salameen, Fadila; Hejji, Ahmad Ben


    The main aim of the study was to test for the presence of Legionnaires' disease-causing microorganisms in air-conditioned buildings in Kuwait using molecular technologies. For this purpose, 547 samples were collected from 38 cooling towers for the analysis of Legionella pneumophila. These samples included those from water (n = 178), air (n = 231), and swabs (n = 138). Out of the 547 samples, 226 (41%) samples were presumptive positive for L. pneumophila, with L. pneumophila viable counts in the positive water samples ranging from 1 to 88 CFU/ml. Of the Legionella culture-positive samples, 204 isolates were examined by latex agglutination. These isolates were predominately identified as L. pneumophila serogroup (sg) 2-14. Using the Dresden panel of monoclonal antibodies, 74 representatives isolates were further serogrouped. Results showed that 51% of the isolates belonged to serogroup 7 followed by 1 (18%) and 3 (18%). Serogroups 4 (4%) and 10 (7%) were isolated at a lower frequency, and two isolates could not be assigned to a serogroup. These results indicate the wide prevalence of L. pneumophila serogroup 7 as the predominant serogroup at the selected sampling sites. Furthermore, the 74 L. pneumophila (sg1 = 13; sg3 = 13; sg4 = 3; sg7 = 38; sg10 = 5; sgX = 2) isolates were genotyped using the seven gene protocol sequence-based typing (SBT) scheme developed by the European Working Group for Legionella Infections (EWGLI). The results show that Legionella isolates were discriminated into nine distinct sequence typing (ST) profiles, five of which were new to the SBT database of EWGLI. Additionally, all of the ST1 serogroup 1 isolates were of the OLDA/Oxford subgroup. These baseline data will form the basis for the development of a Legionella environmental surveillance program and used for future epidemiological investigations.


    Yu. A. Zenovich-Leshkevich-Olpinskiy


    Full Text Available In order to reduce the temperature of cooling water and increase the efficiency of use of power resources the main directions of modernization of systems of technical water supply with cooling towers at steam power plants are presented. The problems of operation of irrigation systems and water distribution systems of cooling towers are reviewed. The design of heat and mass transfer devices, their shortcomings and the impact on the cooling ability of the cooling tower are also under analysis. The use of droplet heat and mass transfer device based on the lattice polypropylene virtually eliminates the shortcomings of the film and droplet-film heat and mass transfer devices of the cooling tower, increasing lifetime, and improving the reliability and efficiency of the operation of the main equipment of thermal power plants. The design of the water distribution devices of cooling towers is also considered. It is noted that the most effective are water-spattering low-pressure nozzles made of polypropylene that provides uniform dispersion of water and are of a high reliability and durability.

  18. Legionnaires’ disease from a cooling tower in a community outbreak in Lidköping, Sweden- epidemiological, environmental and microbiological investigation supported by meteorological modelling

    Ulleryd Peter


    Full Text Available Abstract Background An outbreak of Legionnaires’ Disease took place in the Swedish town Lidköping on Lake Vänern in August 2004 and the number of pneumonia cases at the local hospital increased markedly. As soon as the first patients were diagnosed, health care providers were informed and an outbreak investigation was launched. Methods Classical epidemiological investigation, diagnostic tests, environmental analyses, epidemiological typing and meteorological methods. Results Thirty-two cases were found. The median age was 62 years (range 36 – 88 and 22 (69% were males. No common indoor exposure was found. Legionella pneumophila serogroup 1 was found at two industries, each with two cooling towers. In one cooling tower exceptionally high concentrations, 1.2 × 109 cfu/L, were found. Smaller amounts were also found in the other tower of the first industry and in one tower of the second plant. Sero- and genotyping of isolated L. pneumophila serogroup 1 from three patients and epidemiologically suspected environmental strains supported the cooling tower with the high concentration as the source. In all, two L. pneumophila strains were isolated from three culture confirmed cases and both these strains were detected in the cooling tower, but one strain in another cooling tower as well. Meteorological modelling demonstrated probable spread from the most suspected cooling tower towards the town centre and the precise location of four cases that were stray visitors to Lidköping. Conclusions Classical epidemiological, environmental and microbiological investigation of an LD outbreak can be supported by meteorological modelling methods. The broad competence and cooperation capabilities in the investigation team from different authorities were of paramount importance in stopping this outbreak.

  19. Comparison of plate counts, Petrifilm, dipslides, and adenosine triphosphate bioluminescence for monitoring bacteria in cooling-tower waters.

    Mueller, Sherry A; Anderson, James E; Kim, Byung R; Ball, James C


    Effective bacterial control in cooling-tower systems requires accurate and timely methods to count bacteria. Plate-count methods are difficult to implement on-site, because they are time- and labor-intensive and require sterile techniques. Several field-applicable methods (dipslides, Petrifilm, and adenosine triphosphate [ATP] bioluminescence) were compared with the plate count for two sample matrices--phosphate-buffered saline solution containing a pure culture of Pseudomonas fluorescens and cooling-tower water containing an undefined mixed bacterial culture. For the pure culture, (1) counts determined on nutrient agar and plate-count agar (PCA) media and expressed as colony-forming units (CFU) per milliliter were equivalent to those on R2A medium (p = 1.0 and p = 1.0, respectively); (2) Petrifilm counts were not significantly different from R2A plate counts (p = 0.99); (3) the dipslide counts were up to 2 log units higher than R2A plate counts, but this discrepancy was not statistically significant (p = 0.06); and (4) a discernable correlation (r2 = 0.67) existed between ATP readings and plate counts. For cooling-tower water samples (n = 62), (1) bacterial counts using R2A medium were higher (but not significant; p = 0.63) than nutrient agar and significantly higher than tryptone-glucose yeast extract (TGE; p = 0.03) and PCA (p ATP readings and plate counts varied from system to system, was poor (r2 values ranged from ATP method was not sufficiently sensitive to measure counts below approximately 10(4) CFU/mL.

  20. Noise control of counterflow cooling towers%逆流式冷却塔的噪声治理

    费朝阳; 陈长征; 周勃


    根据逆流式冷却塔辐射噪声的实测频谱图,分析了冷却塔的主要噪声来源和频谱特征.分别从吸声、消声和隔声等方面制定了降噪方案,取得了良好的降噪效果.%Based on the measured radiation noise frequency spectrogram, analyses the main noise source and noise spectrum characteristics of cooling tower.Makes a noise control scheme from the aspects of sound absorption, attenuation and insulation.The effect of the noise control is satisfactory.

  1. Solving the heat transfer in the cold rain of a cross flow cooling tower. N3S code - cooling tower release; Traitement thermique de la zone de pluie des aerorefrigerants a contre-courant. Code N3S - version aerorefrigerants

    Grange, J.L.


    A simplified model for heat and mass transfer in the lower rainfall of a counter-flow cooling toward had to be implemented in the N3S code-cooling tower release It is built from an old code: ZOPLU. The air velocity field is calculated by N3S. The air and water temperature fields are solved by a Runge-Kutta method on a mesh in an adequate number of vertical plans. Heat exchange and drags correlations are given. And all the necessary parameters are specified. All the subroutines are described. They are taken from ZOPLU and modified in order to adapt their abilities to the N3S requirements. (author). 6 refs., 3 figs., 3 tabs., 3 appends.

  2. Acidity of vapor plume from cooling tower mixed with flue gases emitted from coal-fired power plant.

    Hlawiczka, Stanislaw; Korszun, Katarzyna; Fudala, Janina


    Acidity of products resulting from the reaction of flue gas components emitted from a coal-fired power plant with water contained in a vapor plume from a wet cooling tower was analyzed in a close vicinity of a power plant (710 m from the stack and 315 m from the cooling tower). Samples of this mixture were collected using a precipitation funnel where components of the mixed plumes were discharged from the atmosphere with the rainfall. To identify situations when the precipitation occurred at the same time as the wind directed the mixed vapor and flue gas plumes above the precipitation funnel, an ultrasound anemometer designed for 3D measurements of the wind field located near the funnel was used. Precipitation samples of extremely high acidity were identified - about 5% of samples collected during 12 months showed the acidity below pH=3 and the lowest recorded pH was 1.4. During the measurement period the value of pH characterizing the background acidity of the precipitation was about 6. The main outcome of this study was to demonstrate a very high, and so far completely underestimated, potential of occurrence of episodes of extremely acid depositions in the immediate vicinity of a coal-fired power plant.

  3. Research on Group Tower Effectiveness of Super Large Cooling Towe%超大型冷却塔的群塔效应研究



     In the structural design of cooling towers, the group tower effect relates to the plane location of the cooling tower layout and structural design of the cooling tower itself. Different position of the plane causes different group tower effect. In the actual engineer, the unfavorable layout should be avoided, and the effect of the group tower should be taken fully into account.%  在冷却塔结构设计中,群塔效应的影响关系到整个冷却塔平面位置的布置以及冷却塔本身的结构设计。不同的平面位置,群塔效应影响不同。在实际工程中,应尽量避免不利的平面布置,同时应充分考虑群塔效应影响。

  4. Combined Application of Silencer and Sound Barrier in Cooling Tower Noise Control%消声装置和声屏障在冷却塔降噪治理中的组合应用



    针对火电厂自然通风冷却塔的噪声污染,通过分析研究冷却塔噪声特性,以辽宁某电厂冷却塔噪声控制为例,根据厂界及敏感点噪声控制目标,利用CADNA_ A软件进行分析和预测,采取消声装置和声屏障相结合的噪声控制技术,使厂界及敏感点噪声达到相关标准,取得了理想效果,为同类工程噪声治理提供参考。%This paper focused on the noise pollution of natural ventilation cooling tower in power plant. Taking cooling towers in a power plant in Liaoning as an example,the noise characteristics and noise control of cooling towers were analyzed and studied. According to the noise control target of factory circle and sensitive points,the noise distribution was analyzed and forecasted by CADNA_ A software. The result showed that the noise in factory circle and sensitive points reached the relevant standards and achieved the desired results by the combined applica-tion of silencer and sound barrier. This approach provides a reference for similar project.

  5. Application of Noise Reduction Technology in Cooling Tower to Power Plant%冷却塔声源降噪技术在电厂的应用

    金康华; 居国腾


    Based on the noise analysis of characteristics and frequency spectrums in a 5500 m2 Reverse Flow Natural-Ventilation Cooling Tower of Power Plants. By an application example of noise control equipment and technology,A new method for noise control of the cooling tower is proposed.%通过对某电厂5500 m2逆流式自然通风冷却塔的噪声特点和频谱分析,以声源降噪设备和技术应用实例,提出了一种冷却塔噪声治理的新办法。

  6. Proposal for an alternative operative method for determination of polarisation resistance for the quantitative evaluation of corrosion of reinforcing steel in concrete cooling towers

    Mitzithra, M.E., E-mail: [EDF R& D, 6 quai Watier, 78401 Chatou Cedex (France); Université de Toulouse, UPS, INSA, LMDC, 135, Avenue de Rangueil, 31077 Toulouse Cedex 4 (France); Deby, F.; Balayssac, J.P. [Université de Toulouse, UPS, INSA, LMDC, 135, Avenue de Rangueil, 31077 Toulouse Cedex 4 (France); Salin, J. [EDF R& D, 6 quai Watier, 78401 Chatou Cedex (France)


    This paper summarises the results obtained from numerical simulations of an operational measurement mode of polarisation resistance adapted for evaluating corrosion of reinforcing steel in concrete on cooling towers. A simple operational measurement mode of R{sub p} is proposed, adapted for cooling towers prone to corrosion due to carbonation. By means of numerical experimentations, calculation diagrams and semi-empirical equations are built involving the different influencing parameters: concrete cover to steel reinforcement, concrete resistivity and current intensity injected from the counter electrode. Finally, a first application of the proposed procedure for calculating the real value of R{sub p} in laboratory conditions is presented.

  7. Wastewater reuse in a cascade based system of a petrochemical industry for the replacement of losses in cooling towers.

    Hansen, Everton; Rodrigues, Marco Antônio Siqueira; Aquim, Patrice Monteiro de


    This article discusses the mapping of opportunities for the water reuse in a cascade based system in a petrochemical industry in southern Brazil. This industrial sector has a large demand for water for its operation. In the studied industry, for example, approximately 24 million cubic meters of water were collected directly from the source in 2014. The objective of this study was to evaluate the implementation of the reuse of water in cascade in a petrochemical industry, focusing on the reuse of aqueous streams to replenish losses in the cooling towers. This is an industrial scale case study with real data collected during the years 2014 and 2015. Water reuse was performed using heuristic approach based on the exploitation of knowledge acquired during the search process. The methodology of work consisted of the construction of a process map identifying the stages of production and water consumption, as well as the characterization of the aqueous streams involved in the process. For the application of the industrial water reuse as cooling water, mass balances were carried out considering the maximum concentration levels of turbidity, pH, conductivity, alkalinity, calcium hardness, chlorides, sulfates, silica, chemical oxygen demand and suspended solids as parameters turbidity, pH, conductivity, alkalinity, calcium hardness, chlorides, sulfates, silica, chemical oxygen demand and suspended solids as parameters. The adopted guideline was the fulfillment of the water quality criteria for each application in the industrial process. The study showed the feasibility for the reuse of internal streams as makeup water in cooling towers, and the implementation of the reuse presented in this paper totaled savings of 385,440 m(3)/year of water, which means a sufficient volume to supply 6350 inhabitants for a period of one year, considering the average water consumption per capita in Brazil; in addition to 201,480 m(3)/year of wastewater that would no longer be generated.

  8. Low energy cooling of the White Tower, functioning as a contemporary museum

    Papadopoulos, A.M.; Avgelis, A.; Anastaselos, D. [Laboratory of Heat Transfer and Environmental Engineering, Department of Mechanical Engineering, School of Engineering, Aristotle University of Thessaloniki, Thessaloniki (Greece)


    Historical buildings are of significance not only because they preserve the cultural heritage of nations but also because of their representative character. However, as buildings they not necessarily provide satisfactory comfort and health conditions, despite the fact that they can be high-energy consumers. The Museum of Byzantine Culture in Thessaloniki has decided to convert the White Tower, a six-floor fortress dating back to the 15th century, into a contemporary city museum with means of audiovisual, virtual and information technologies. A study has been carried out in 2005-2006 to determine the possibilities, given the restrictions applying, to implement measures in order to establish and maintain satisfactory thermal comfort and indoor air quality conditions in the White Tower, whilst ensuring its unobstructed function as a contemporary city museum. The measurements and simulations carried out, together with the resulting suggested interventions are discussed in this paper. (author)

  9. Controlled cooling of an electronic system based on projected conditions

    David, Milnes P.; Iyengar, Madhusudan K.; Schmidt, Roger R.


    Energy efficient control of a cooling system cooling an electronic system is provided based, in part, on projected conditions. The control includes automatically determining an adjusted control setting(s) for an adjustable cooling component(s) of the cooling system. The automatically determining is based, at least in part, on projected power consumed by the electronic system at a future time and projected temperature at the future time of a heat sink to which heat extracted is rejected. The automatically determining operates to reduce power consumption of the cooling system and/or the electronic system while ensuring that at least one targeted temperature associated with the cooling system or the electronic system is within a desired range. The automatically determining may be based, at least in part, on an experimentally obtained model(s) relating the targeted temperature and power consumption of the adjustable cooling component(s) of the cooling system.

  10. Controlled cooling of an electronic system based on projected conditions

    David, Milnes P.; Iyengar, Madhusudan K.; Schmidt, Roger R.


    Energy efficient control of a cooling system cooling an electronic system is provided based, in part, on projected conditions. The control includes automatically determining an adjusted control setting(s) for an adjustable cooling component(s) of the cooling system. The automatically determining is based, at least in part, on projected power consumed by the electronic system at a future time and projected temperature at the future time of a heat sink to which heat extracted is rejected. The automatically determining operates to reduce power consumption of the cooling system and/or the electronic system while ensuring that at least one targeted temperature associated with the cooling system or the electronic system is within a desired range. The automatically determining may be based, at least in part, on an experimentally obtained model(s) relating the targeted temperature and power consumption of the adjustable cooling component(s) of the cooling system.

  11. An experimental investigation on air-side performances of finned tube heat exchangers for indirect air-cooling tower

    Du Xueping


    Full Text Available A tremendous quantity of water can be saved if the air cooling system is used, comparing with the ordinary water-cooling technology. In this study, two kinds of finned tube heat exchangers in an indirect air-cooling tower are experimentally studied, which are a plain finned oval-tube heat exchanger and a wavy-finned flat-tube heat exchanger in a cross flow of air. Four different air inlet angles (90°, 60 °, 45°, and 30° are tested separately to obtain the heat transfer and resistance performance. Then the air-side experimental correlations of the Nusselt number and friction factor are acquired. The comprehensive heat transfer performances for two finned tube heat exchangers under four air inlet angles are compared. For the plain finned oval-tube heat exchanger, the vertical angle (90° has the worst performance while 45° and 30° has the best performance at small ReDc and at large ReDc, respectively. For the wavy-finned flat-tube heat exchanger, the worst performance occurred at 60°, while the best performance occurred at 45° and 90° at small ReDc and at large ReDc, respectively. From the comparative results, it can be found that the air inlet angle has completely different effects on the comprehensive heat transfer performance for the heat exchangers with different structures.

  12. One hundred years of natural-draught cooling tower. The `cool end` of electricity generation celebrates its centennial; 100 Jahre Naturzug-Kuehlturm. Das ``kuehle Ende`` der Stromerzeugung feiert Jubilaeum



    Looming upto 200 m high into the sky like waisted giant tubes, natural-draught cooling towers typify the appearance of power plants throughout the world. In shape and statics these grey-shelled core-cooled giants are relatives of the Eiffel Tower in Paris. One thing the natural-draught cooling tower reflects more than anything else in the 100 years` development since its introduction to the market is the advance of power plant technology and industrialisation. (orig.) [Deutsch] Sie ragen wie dynamisch geschwungene Riesen-Roehren bis zu 200 Meter hoch in den Himmel und praegen das Erscheinungsbild von Kraftwerken in aller Welt: Naturzug-Kuehltuerme. In Form und Statik sind diese Giganten mit grauer Schale und kuehlem Kern Verwandte des Pariser Eiffelturms. Seit seiner Markteinfuehrung vor 100 Jahren spiegelt die Entwicklung des Naturzug-Kuehlturms aber vor allem eines wieder: Den Fortschritt der Kraftwerkstechnik und der Industrialisierung. (orig.)

  13. Mathematical Model of Two Phase Flow in Natural Draft Wet-Cooling Tower Including Flue Gas Injection

    Hyhlík Tomáš


    Full Text Available The previously developed model of natural draft wet-cooling tower flow, heat and mass transfer is extended to be able to take into account the flow of supersaturated moist air. The two phase flow model is based on void fraction of gas phase which is included in the governing equations. Homogeneous equilibrium model, where the two phases are well mixed and have the same velocity, is used. The effect of flue gas injection is included into the developed mathematical model by using source terms in governing equations and by using momentum flux coefficient and kinetic energy flux coefficient. Heat and mass transfer in the fill zone is described by the system of ordinary differential equations, where the mass transfer is represented by measured fill Merkel number and heat transfer is calculated using prescribed Lewis factor.

  14. A Spanish 'power tower' solar system - Project CESA-1

    Munoz Torralbo, A.; Hernandez Gonzalvez, C.; Ortiz Roses, C.; Avellaner Lacal, J.; Sanchez, F.


    Attention is given to the design features, development and construction status, and performance capabilities of the CESA-1 solar thermal central receiver system project. The heliostat field includes 300 units of two different types, and the central receiver is of water-steam cavity type. Power conversion is by means of a regenerative Rankine cycle whose primary component is a turbogenerator with multistage condensing turbine. A molten salt sensible heat storage system is incorporated. Detailed specifications are given for all operating parameters.

  15. Lattice Regenerative Cooling Methods (LRCM) Project

    National Aeronautics and Space Administration — ORBITEC proposes to develop and demonstrate a novel cooling concept called Lattice Regenerative Cooling Methods (LRCM) for future high thrust in-space propulsion...

  16. Distribution of sequence-based types of legionella pneumophila serogroup 1 strains isolated from cooling towers, hot springs, and potable water systems in China.

    Qin, Tian; Zhou, Haijian; Ren, Hongyu; Guan, Hong; Li, Machao; Zhu, Bingqing; Shao, Zhujun


    Legionella pneumophila serogroup 1 causes Legionnaires' disease. Water systems contaminated with Legionella are the implicated sources of Legionnaires' disease. This study analyzed L. pneumophila serogroup 1 strains in China using sequence-based typing. Strains were isolated from cooling towers (n = 96), hot springs (n = 42), and potable water systems (n = 26). Isolates from cooling towers, hot springs, and potable water systems were divided into 25 sequence types (STs; index of discrimination [IOD], 0.711), 19 STs (IOD, 0.934), and 3 STs (IOD, 0.151), respectively. The genetic variation among the potable water isolates was lower than that among cooling tower and hot spring isolates. ST1 was the predominant type, accounting for 49.4% of analyzed strains (n = 81), followed by ST154. With the exception of two strains, all potable water isolates (92.3%) belonged to ST1. In contrast, 53.1% (51/96) and only 14.3% (6/42) of cooling tower and hot spring, respectively, isolates belonged to ST1. There were differences in the distributions of clone groups among the water sources. The comparisons among L. pneumophila strains isolated in China, Japan, and South Korea revealed that similar clones (ST1 complex and ST154 complex) exist in these countries. In conclusion, in China, STs had several unique allelic profiles, and ST1 was the most prevalent sequence type of environmental L. pneumophila serogroup 1 isolates, similar to its prevalence in Japan and South Korea.

  17. The necessity of Energy-Saving Reconstruct of Circulating Water Cooling Tower%循环水冷却塔节能改造必要性



    The article introduces the traditional cooling tower motor reducer drive and newly developed energy-saving water power during the 12th Five Year Plan Period. Taking the circulating water cooling tower transformation technology of Guixi smelter for exam-ple, the cooling tower fan rotating was driven by water power machine instead of the motor, coupling and reducer in traditional cooling tower. Thus, the equipment investment and electricity load were reduced to realize the energy-saving effect.%介绍传统冷却塔电机减速机传动和十二五期间新研发的节能水能机,并以贵溪冶炼厂循环水冷却塔改造技术为例,即将冷却塔由水能机驱动风机旋转,代替传统冷却塔中的电机、联轴器、减速机,以减少设备投入,降低用电负荷,达到预期节能效果。

  18. A descaling treatment for aerated water, especially in cooling towers; Procede de traitement antitartre d`eau aeree, notamment dans les refrigerants atmospheriques

    Delemont, F.; Mureau, P.


    Carbon dioxide is injected into the water aerating air, for example in the water flowing in a cooling tower; the dissolved carbon dioxide prevents scaling to take place on the heat exchange surfaces or leads to the dissolution of the deposited scale. This system has the advantage to avoid any acid use and thus polluting effluents. 2 refs.

  19. A comparison of cooling tower systems. Analysis of high-efficiency closed hybrid-medium counter-current cooling system; Koeltorensystemen vergeleken. Analyse hoog rendement gesloten hybride-mediumterugkoeler

    Huizinga, H.T. [Heat Transfer Holland, Zuidwolde (Netherlands)


    Cooling towers are also utilized in climate technique to dispose of process heat. Water use, the added chemicals and the cleaning cost constitute the largest debit items in exploitation. Open wet cooling towers use water all through the year. The closed hybrid medium blast cooler only uses water in the summer. (mk) [Dutch] Koeltorens worden, ook in de klimaattechniek, ingezet om proceswarmte af te voeren. Het waterverbruik, de toegevoegde chemicalien en de schoonmaakkosten behoren tot de grotere kostenposten in de exploitatie. Open natte koeltorens verbruiken het hele jaar door water. De gesloten hybride-mediumterugkoeler verbruikt alleen water in de zomer.

  20. Combined thermal storage pond and dry cooling tower waste heat rejection system for solar-thermal steam-electric power plants. Final report

    Guyer, E.C.; Bourne, J.G.; Brownell, D.L.; Rose, R.M.


    The thermal performance and economics of the combined thermal storage pond and dry cooling tower waste heat rejection system concept for solar-thermal steam-electric plants have been evaluated. Based on the computer simulation of the operation of southwest-sited solar-thermal plants, it has been determined that the combined pond-tower concept has significant cost and performance advantages over conventional dry cooling systems. Use of a thermal storage pond as a component of the dry cooling system allows a significant reduction in the required dry cooling heat exchange capacity and the associated parasitic power consumption. Importantly, it has been concluded that the combined pond-tower dry cooling system concept can be employed to economically maintain steam condensing temperatures at levels normally achieved with conventional evaporative cooling systems. An evaluation of alternative thermal storage pond design concepts has revealed that a stratified vertical-flow cut-and-fill reservoir with conventional membrane lining and covering would yield the best overall system performance at the least cost.

  1. Controlled Blasting Demolition of Two Cooling Towers under Complicated Environment%复杂环境下2座冷却塔控制爆破拆除

    祁亚静; 杨小林; 褚怀保; 张英才


    Two cooling towers with 75 meters in height and 62. 84 meters in diameter in the complicated circumstances were dem- olished by directional blasting. According to the structural features,the surrounding environment and safety requirements of the cooling tower, nine shock absorption windows were opened on the front tower in the dumped direction of cooling tower,only the pillar of the cooling tower was blasted so that the wall of the cooling tower landing lightly, and the blasting take the Security measures such as duplex burst gap that pre-open a dormer and offload tank. Combined with the collapsed reasons of bursting of the cooling tower, take the method of two cooling lowers collapsed oppositely. In addition, the measured data are analyzed for the vibration, which verifies that the vibration damping effects are significantly,the measured vibration value is less than the theoretical calculated value.%采用定向倾倒控制爆破技术成功地拆除了复杂环境下2座高度分别为75 m、底部直径为62.63 m的冷却塔.针对冷却塔结构的特点,周围环境及安全要求,在冷却塔倾倒方向的正面塔体上开了9个减震窗口,仅对冷却塔人字支柱进行爆破,实现冷却塔壁体轻着落,并采取了封闭式防护和开挖减振沟及铺设缓冲垫层等安全防护措施.结合冷却塔爆破自身垮落原因,采取两冷却塔相向倒塌.此外,利用实测数据对触地振动进行了分析,验证了控振措施减振效果明显,实测振速值小于理论计算振速.

  2. Status of the Fermilab electron cooling project

    Nagaitsev, S. E-mail:; Burov, A.; Carlson, K.; Dudnikov, V.; Kramper, B.; Kroc, T.; Leibfritz, J.; McGee, M.; Saewert, G.; Schmidt, C.W.; Shemyakin, A.; Warner, A.; Seletsky, S.; Tupikov, V


    A prototype of a 4.3-MeV electron cooling system has been assembled at Fermilab as part of the on-going R and D program in high-energy electron cooling. This electron cooler prototype will not demonstrate the actual cooling but it would allow to determine if the electron beam properties are suitable for antiproton beam cooling. An electron beam is accelerated by a 5-MV Pelletron (Van de Graaff type) accelerator and transported to a prototype cooling section. The cooling would take place in a 20-m long solenoid flanked on both sides by supply and return beam-lines--a total of 60 m of transport channel. This paper describes the status of the electron cooling R and D program.

  3. Testing and numerical simulation of natural draft cooling tower%自然通风冷却塔运行实测与模拟

    胡天乐; 谢晓云; 江亿


    Through practical measurement on a natural draft cooling tower in a 150 MW unit,the efficiency and coefficient of heat and mass transfer in the tower were obtained,and several problems during the tower operation and its performance optimization direction were found.On this basis,the temperature and pres-sure distribution in rain area and filling area of the cooling tower were numerically simulated.The results show that,with the filling material thickness of 3.0 m inside the cooling tower,42.1% temperature drop needs 55.8% pressure loss,and the optimum thickness of the padding is around 2.5 m.The optimum oper-ation strategy of this circulating cooling water pump is one pump with two towers,and the wet bulb effi-ciency of the cooling tower can reach 75.0%,the net power generation can increase by 3.007 MW com-pared with the unit using two pumps with one tower strategy.%通过对某150 MW机组的自然通风冷却塔进行实际测试,得到该冷却塔的热质交换效率与系数,并发现其运行过程中的一些问题及性能优化方向;基于此,采用微元差分法对该冷却塔的雨区和填料区进行温度及压力分布的数值模拟.结果表明:在该冷却塔的填料厚度为3.0 m时,其仅贡献42.1%的温降却需要损耗55.8%的空气压降,冷却塔最优填料厚度约为2.5 m;该机组的最优循环冷却水泵运行策略为1泵拖2塔,此时冷却塔的湿球效率可达75.0%,机组净发电量比其他循环冷却水泵运行策略多3.007 MW.

  4. An Energy-Saving Optimisation of the Large-Scale Cross-Flow Cooling Tower%大型横流塔的节能优化方案



    大型横流冷却塔一般采用钢筋混凝土结构,近年来在我国发展迅速。本研究旨在通过消除气场涡流降低风阻及改进填料等手段提高冷却塔冷却效率。原塔设计填料为75mm×35mm×30°P.V.C薄膜式填料,实际运行冷却效率0.623,与设计要求的0.75相比差距较大。通过优化改造设计,单塔风量提高50%以上,单位千瓦电耗产风量提高40%,单塔出水温度降低2℃,冷却效率达0.788。%The large-scale cross-flow cooling tower generally using reinforced concrete structure has recently been developed rapidly in China. A study was carried out to improve its cooling efficiency through eliminating eddy in the air-flow field to reduce drag, improving packing, and etc. The filler of the original tower design was 75 mm ×35 mm×30° PVC film packing. The cooling efficiency of practical operation was only 0.623, far lower than 0.75 of the design specification. By an optimal renovation in design of the cross-flow cooling tower, air volume of a single tower increased by 50%, air output per kilowatt power consumption raised 40% and outlet water temperature of the single tower decreased 2 ℃ whilst the cooling efficiency reached 0.788.

  5. Natural Pathogen Control Chemistry to Replace Toxic Treatment of Microbes and Biofilm in Cooling Towers.

    Brouse, Lon; Brouse, Richard; Brouse, Daniel


    Application of toxic antibacterial agents is considered necessary to control prevalent fresh water microorganisms that grow in evaporative cooling water systems, but can adversely affect the environment and human health. However, natural antibacterial water chemistry has been applied in industrial cooling water systems for over 10 years to inhibit microorganisms with excellent results. The water chemistry method concentrates natural minerals in highly-softened water to produce elevated pH and dissolved solids, while maintaining low calcium and magnesium content. The method provides further benefits in water conservation, and generates a small volume of non-toxic natural salt concentrate for cost efficient separation and disposal if required. This report describes the antimicrobial effects of these chemistry modifications in the cooling water environment and the resultant collective inhibition of microbes, biofilm, and pathogen growth. This article also presents a novel perspective of parasitic microbiome functional relationships, including "Trojan Protozoans" and biofilms, and the function of polyvalent metal ions in the formation and inhibition of biofilms. Reducing global dependence on toxic antibacterial agents discharged to the environment is an emerging concern due to their impact on the natural microbiome, plants, animals and humans. Concurrently, scientists have concluded that discharge of antibacterial agents plays a key role in development of pathogen resistance to antimicrobials as well as antibiotics. Use of natural antibacterial chemistry can play a key role in managing the cooling water environment in a more ecologically sustainable manner.

  6. Analysis and Application of Noise Reduction in Metro Cooling Tower%地铁冷却塔消声降噪分析及应用探讨



    由于部分敏感区域的声环境质量标准与冷却塔产品的国家标准存在差异性,容易引起二类声环境区噪声超标,本文以广佛地铁某站点冷却塔降噪方案及广州地铁六号线某站点冷却塔降噪方案为实例,从冷却塔设计及设置、冷却塔增设消声围蔽、冷却塔噪声源消声治理等方面进行研究,并结合治理效果对城市冷却塔消声治理提出建议。%Because of the diversity between environmental quality standard for noise and cooling tower′s national standard in some susceptible area , the second category of acoustic environment noise will be over standard easi-ly.This paper , taking cooling tower noise reduction scheme in a metro station of GuangZhou Metro Line 6 and Guangfo Line as an example , studies the design and placement of cooling tower , the addition of noise reduction en-closure , noise silencing governance , etc.Furthermore , combined with the treatment effect , it put forward sugges-tions for the control of the cooling tower noise elimination .

  7. Cooled Bolometer IR Monolithic FPA Project

    National Aeronautics and Space Administration — Future space-based observatories imaging in the 4-40 lm spectral regime will be passively cooled. The objective of this research effort is to demonstrate near...

  8. Performance Analysis of XCPC Powered Solar Cooling Demonstration Project

    Widyolar, Bennett K.

    A solar thermal cooling system using novel non-tracking External Compound Parabolic Concentrators (XCPC) has been built at the University of California, Merced and operated for two cooling seasons. Its performance in providing power for space cooling has been analyzed. This solar cooling system is comprised of 53.3 m2 of XCPC trough collectors which are used to power a 23 kW double effect (LiBr) absorption chiller. This is the first system that combines both XCPC and absorption chilling technologies. Performance of the system was measured in both sunny and cloudy conditions, with both clean and dirty collectors. It was found that these collectors are well suited at providing thermal power to drive absorption cooling systems and that both the coinciding of available thermal power with cooling demand and the simplicity of the XCPC collectors compared to other solar thermal collectors makes them a highly attractive candidate for cooling projects.

  9. Corrosion control when using secondary treated municipal wastewater as alternative makeup water for cooling tower systems.

    Hsieh, Ming-Kai; Li, Heng; Chien, Shih-Hsiang; Monnell, Jason D; Chowdhury, Indranil; Dzombak, David A; Vidic, Radisav D


    Secondary treated municipal wastewater is a promising alternative to fresh water as power plant cooling water system makeup water, especially in arid regions. Laboratory and field testing was conducted in this study to evaluate the corrosiveness of secondary treated municipal wastewater for various metals and metal alloys in cooling systems. Different corrosion control strategies were evaluated based on varied chemical treatment. Orthophosphate, which is abundant in secondary treated municipal wastewater, contributed to more than 80% precipitative removal of phosphorous-based corrosion inhibitors. Tolyltriazole worked effectively to reduce corrosion of copper (greater than 95% inhibition effectiveness). The corrosion rate of mild steel in the presence of free chlorine 1 mg/L (as Cl2) was approximately 50% higher than in the presence of monochloramine 1 mg/L (as Cl2), indicating that monochloramine is a less corrosive biocide than free chlorine. The scaling layers observed on the metal alloys contributed to corrosion inhibition, which could be seen by comparing the mild steel 21-day average corrosion rate with the last 5-day average corrosion rate, the latter being approximately 50% lower than the former.

  10. Solar heating and cooling. Research and development: project summaries


    The Conservation and Solar Applications Solar Heating and Cooling Research and Development Program is described. The evolution of the R and D program is described and the present program is outlined. A series of project descriptions summarizes the research and development presently supported for further development of collectors, thermal energy storage and heat exchangers, heat pumps, solar cooling, controls, and systems. (MHR)

  11. The design of the optical modules of the KM3NeT-Italia project towers

    Leonora, Emanuele; Aiello, Sebastiano; Giordano, Valentina


    The KM3NeT-Italia project aims to construct a large volume underwater neutrino telescope, to be installed in the depths of the Mediterranean Sea. The R&D and mass production phases of the detection elements of the telescope, the optical modules, were entirely performed in the INFN-LNS site in the harbour of Catania. In November 2014 a first tower of 14 storeys equipped with 84 optical modules was successfully deployed in the Mediterranean Sea site. The design of the optical modules and their main components are described in this paper.

  12. Enhanced Biocide Treatments with D-amino Acid Mixtures against a Biofilm Consortium from a Water Cooling Tower

    Ru Jia


    Full Text Available Different species of microbes form mixed-culture biofilms in cooling water systems. They cause microbiologically influenced corrosion (MIC and biofouling, leading to increased operational and maintenance costs. In this work, two D-amino acid mixtures were found to enhance two non-oxidizing biocides [tetrakis hydroxymethyl phosphonium sulfate (THPS and NALCO 7330 (isothiazoline derivatives] and one oxidizing biocide [bleach (NaClO] against a biofilm consortium from a water cooling tower in lab tests. Fifty ppm (w/w of an equimass mixture of D-methionine, D-leucine, D-tyrosine, D-tryptophan, D-serine, D-threonine, D-phenylalanine, and D-valine (D8 enhanced 15 ppm THPS and 15 ppm NALCO 7330 with similar efficacies achieved by the 30 ppm THPS alone treatment and the 30 ppm NALCO 7330 alone treatment, respectively in the single-batch 3-h biofilm removal test. A sequential treatment method was used to enhance bleach because D-amino acids react with bleach. After a 4-h biofilm removal test, the sequential treatment of 5 ppm bleach followed by 50 ppm D8 achieved extra 1-log reduction in sessile cell counts of acid producing bacteria, sulfate reducing bacteria, and general heterotrophic bacteria compared with the 5 ppm bleach alone treatment. The 10 ppm bleach alone treatment showed a similar efficacy with the sequential treatment of 5 ppm bleach followed by 50 ppm D8. The efficacy of D8 was found better than that of D4 (an equimass mixture of D-methionine, D-leucine, D-tyrosine, and D-tryptophan in the enhancement of the three individual biocides against the biofilm consortium.

  13. Cooling tower restoration in the joint nuclear power station Neckar 1; Kuehlturmsanierung im Gemeinschaftskernkraftwerk Neckar 1

    Ernst, G. [Karlsruhe Univ. (T.H.) (Germany). Inst. fuer Technische Thermodynamik; Braeuning, G. [Karlsruhe Univ. (T.H.) (Germany). Inst. fuer Technische Thermodynamik; Dekker, G. [Marley Kuehlturm GmbH, Duesseldorf (Germany). Bereich Vertrieb neuer Kuhlturm-Anlagen


    Since the starting operation of the Power Station GKN I (Joint Nuclear Power Station Neckar I) in the year 1976, the cell cooler of the plant was, except for those cases in which continuous-flow cooling was possible, continually in operation. Aim of the restoration, after an operational time of 17 years, is a further constructional and thermal service life of about 15 to 20 years. (orig.) [Deutsch] Seit der Inbetriebnahme des Kraftwerkes GKN I im Jahr 1976 war der Zellenkuehler der Anlage bis auf die Faelle, in denen Durchlaufkuehlung moeglich war, ununterbrochen in Betrieb. Ziel der Sanierung nach ueber 17jaehriger Betriebszeit ist eine weitere bauliche und thermische Nutzungsdauer von etwa 15 bis 20 Jahren. (orig.)

  14. Modular Spray-Cooled Assemblies for High Heat Fluxes Project

    National Aeronautics and Space Administration — This NASA SBIR Phase II project will produce a flight suitable test bench based on a modular spray-cooled assembly that considers NASA power and mass budgets and can...

  15. Characteristics of a pink-pigmented bacterium isolated from biofilm in a cooling tower in Tokyo, Japan.

    Furuhata, Katsunori; Goto, Keiichi; Kato, Yuko; Saitou, Keiko; Sugiyama, Jun-ichi; Hara, Motonobu; Yoshida, Shin-ichi; Fukuyama, Masafumi


    Strain K-20, a Gram-negative, non-motile, non-spore-forming and strictly aerobic rod, which produces a pale pink pigment, was isolated from biofilm in a cooling tower in Tokyo, Japan. The taxonomic feature of the strain was studied using phenotypic tests and phylogenetic analysis. Phylogenetic analysis of 16S rRNA gene sequences showed that the strain was related to Roseomonas gilardii subsp. rosea, Roseomonas gilardii subsp. gilardii, Roseomonas cervicalis and Roseomonas mucosa at 94.3-94.6 sequence similarities. Growth occurred at 25-40 C and pH 5.0-10.0, optimal at 35 C and pH 7.0. Growth did not occur in the presence of >or=2% NaCl. The API 20NE identification system gave a positive result for urease, L-arabinose, potassium gluconate, adipic acid, malic acid and trisodium citrate (API code number 0201465). The predominant fatty acids of strain K-20 were C18:1Delta11 (50.8%) and C16:1 (17.2%). Cells contained ubiquinone 10 (Q-10) as the major quinone and the G+C content was 72.0 mol%. Based on phenotypic, chemotaxonomic and phylogenetic data, it was assumed that strain K-20 (=JCM 14634) is a novel species of the genus Roseomonas.

  16. Roseomonas tokyonensis sp. nov. isolated from a biofilm sample obtained from a cooling tower in Tokyo, Japan.

    Furuhata, Katsunori; Ishizaki, Naoto; Edagawa, Akiko; Fukuyama, Masafumi


    Strain K-20(T), a Gram-negative, nonmotile, nonspore-forming and strictly aerobic coccobacillus, which produces a pale pink pigment (R2A agar medium, 30℃, seven days) was isolated from a sample of biofilm obtained from a cooling tower in Tokyo, Japan. A phylogenetic analysis of the 16S rRNA partial gene sequences (1,439 bp) showed that the strain (accession number: AB297501) was related to Roseomonas frigidaquae CW67(T) and Roseomonas stagni HS-69(T) with 97.4% and 96.9% sequence similarity, respectively. Strain K-20(T) formed a distinct cluster with Roseomonas frigidaquae CW67(T) in the phylogenetic tree at a high bootstrap value (93%); however, distance was recognized between the strains. In addition, the DNA-DNA hybridization level between strain K-20(T) and Roseomonas frigidaquae JCM 15073(T) was 33%. The taxonomic data indicate that K-20(T) (=JCM 14634(T) =KCTC 32152(T)) should be classified in the genus Roseomonas as the type strain of a novel species, Roseomonas tokyonensis sp. nov.

  17. Biocide efficiency against Legionellae and amoebae in cooling towers - the necessity to control the risk of Legionnaires' disease

    Guhl, W.; Hater, W.; Stumpe, S. [Henkel KGaA, Duesseldorf (Germany)


    Legionella, known to be the causative agent of Legionnaires' disease, is a wide-spread bacteria occurring naturally in water. Favorable growing conditions in man-made systems can lead to massive growth and thus to a considerable risk for human beings. Evaporative cooling towers provide good living conditions due to their operational conditions. As a consequence, the growth of Legionella in these systems has to be controlled. Amongst other measures biocides are dosed to control the growth of the microbiological population and thus the possible risk of an infection by Legionellae. However, Legionella preferably lives in biofilms and/or amoebae, which strongly shelter this microbe. Furthermore, amoebae by themselves can be harmful to humans as well. Therefore, a biocide treatment should control Legionella (planktonic in water and in biofilms/amoebae) as well as the amoebae. This paper shows that an adapted biocide treatment can increase the efficiency of a biocide against Legionellae and amoebae und therefore minimize the risk of an infection by Legionella. (orig.)

  18. Suncatcher and cool pool. Project report

    Hammond, J.


    The Suncatcher is a simple, conical solar concentrating device that captures light entering clerestory windows and directs it onto thermal storage elements at the back of a south facing living space. The cone shape and inclination are designed to capture low angle winter sunlight and to reflect away higher angle summer sunlight. It is found that winter radiation through a Suncatcher window is 40 to 50% higher than through an ordinary window, and that the average solar fraction is 59%. Water-filled steal culvert pipes used for thermal storage are found to undergo less stratification, and thus to be more effective, when located where sunlight strikes the bottom rather than the top. Five Suncatcher buildings are described. Designs are considered for 32/sup 0/, 40/sup 0/ and 48/sup 0/ north latitude, and as the latitude increases, the inclination angle of the cone should be lowered. The Cool Pool is an evaporating, shaded roof pond which thermosiphons cool water into water-filled columns within a building. Preliminary experiments indicate that the best shade design has unimpeded north sky view, good ventilation, complete summer shading, a low architectural profile, and low cost attic vent lowers work. Another series of experiments established the satisfactory performance of the Cool Pool on a test building using four water-filled cylinders, two cylinders, and two cylinders connected to the Cool Pool through a heat exchanger. Although an unshaded pool cools better at night than a shaded one, daytime heat gain far offsets this advantage. A vinyl waterbag heat exchanger was developed for use with the Cool Pool. (LEW)

  19. Solar heating and cooling demonstration project summaries


    Brief descriptive overviews are presented of the design and operating characteristics of all commercial and Federal residential solar heating and cooling systems and of the structures themselves. Also included are available pictures of the buildings and simplified solar system diagrams. A list of non-Federal residential installations is provided.

  20. Analysis of Cooling System for UHVDC Transmission Thyristor Valve Tower%向家坝—上海特高压直流输电换流阀塔水路的分析

    焦秀英; 刘宁


    Of all the faults about system breakdown in 18 UHVDC transmission projects in China, about one third is attributed to the cooling system of HVDC transmission thyristor valve. Therefore, the modification of the water-way structure in the Fulong substation's thyristor valve tower in 800 kV Xiangjiaba-to-Shanghai UHVDC project is described, and the difference between the valve towers in 800 kV Xiangjiaba-to-Shanghai UHVDC project and 500 kV Guizhou-to-Guangdong UHVDC project is analyzed, in order to provide some information for the design of similar valve towers.%纵观目前国内已投运和在建的18个直流输电工程,关于直流停运的事故原因中,由于直流输电换流阀水冷系统故障而停运几乎占到所有事故原因的1/3.笔者主要通过对800 kV向家坝—上海直流输电工程复龙站换流阀塔内水路结构改进的描述,以及分析向家坝—上海直流输电换流阀中与贵州—广东500 kV直流输电换流阀的区别,希望能够对今后直流输电换流阀的设计提供一些经验和方法.

  1. More iPhone Cool Projects

    Smith, B; Palm, Leon; Smith, David; Smith, Charles; Hoefele, Claus; Pflug, Florian; Colgan, Tony; Mora, Saul; de Vries, Arne


    Everyone is developing iPhone applications, and it's clear why. The iPhone is the coolest mobile device available, and the App Store makes it simple to get an application out into the unstoppable iPhone app market. With hundreds of thousands of app developers entering the game, it's crucial to learn from those who have actually succeeded. This book shows you how some of the most innovative and creative iPhone application developers have developed cool, best-selling apps. Not only does every successful application have a story, but behind every great app is excellent code. In this book, you'll




    The main performance limitation for RHIC is emittance growth caused by IntraBeam Scattering during the store. We have developed a longitudinal bunched-beam stochastic cooling system in the 5-8 GHz band which will be used to counteract IBS longitudinal emittance growth and prevent de-bunching during the store. Solutions to the technical problems of achieving sufficient kicker voltage and overcoming the electronic saturation effects caused by coherent components within the Schottky spectrum are described. Results from tests with copper ions in RHIC during the FY05 physics run, including the observation of signal suppression, are presented.

  3. Actively Cooled Ceramic Composite Nozzle Material Project

    National Aeronautics and Space Administration — The Phase I Project demonstrated the capability of the Pyrowave? manufacturing process to produce fiber-reinforced ceramics (FRCs) with integral metal features, such...

  4. Lawrence Livermore National Laboratory (LLNL) Experimental Test Site (Site 300) Salinity Evaluation and Minimization Plan for Cooling Towers and Mechanical Equipment Discharges

    Daily III, W D


    This document was created to comply with the Central Valley Regional Water Quality Control Board (CVRWQCB) Waste Discharge Requirement (Order No. 98-148). This order established new requirements to assess the effect of and effort required to reduce salts in process water discharged to the subsurface. This includes the review of technical, operational, and management options available to reduce total dissolved solids (TDS) concentrations in cooling tower and mechanical equipment water discharges at Lawrence Livermore National Laboratory's (LLNL's) Experimental Test Site (Site 300) facility. It was observed that for the six cooling towers currently in operation, the total volume of groundwater used as make up water is about 27 gallons per minute and the discharge to the subsurface via percolation pits is 13 gallons per minute. The extracted groundwater has a TDS concentration of 700 mg/L. The cooling tower discharge concentrations range from 700 to 1,400 mg/L. There is also a small volume of mechanical equipment effluent being discharged to percolation pits, with a TDS range from 400 to 3,300 mg/L. The cooling towers and mechanical equipment are maintained and operated in a satisfactory manner. No major leaks were identified. Currently, there are no re-use options being employed. Several approaches known to reduce the blow down flow rate and/or TDS concentration being discharged to the percolation pits and septic systems were reviewed for technical feasibility and cost efficiency. These options range from efforts as simple as eliminating leaks to implementing advanced and innovative treatment methods. The various options considered, and their anticipated effect on water consumption, discharge volumes, and reduced concentrations are listed and compared in this report. Based on the assessment, it was recommended that there is enough variability in equipment usage, chemistry, flow rate, and discharge configurations that each discharge location at Site 300

  5. 节能降噪冷却塔的应用综述%Summary on Energy-saving and Noise Reduction Cooling Tower

    杨护洲; 杨若松


    节能型自然通风冷却塔带有高位收水器和高位集水池,具有降噪的特点。超大高位收水冷却塔是从大型核电工程开始应用的,也适用大型火电工程;掌握其适用条件十分重要。%Energy-saving nature draft cooling tower with high-level cold water collectors and high-level basin, there are noise reduction characteristic. The super large tower with high-level cold water collectors are used begin from a large-scale nuclear power engineering applications, is also applicable to fossil fuel power plant;Master the applicable conditions is very important.

  6. Successful implementation of ageing management exemplified at the cooling tower of Emsland nuclear power plant; Erfolgreiche Umsetzung von Alterungsmanagement am Beispiel Kuehlturm des Kernkraftwerkes Emsland

    Fischer, Alexander [Hochtief Solutions AG, Consult IKS Energy, Frankfurt am Main (Germany). Design Kraftwerke; Dueweling, Carsten [Kernkraftwerke Lippe-Ems GmbH, Lingen (Germany). Abschnitt Bautechnik


    The present paper describes the successful implementation of the restoration of water-distribution channels at the cooling tower of the Emsland nuclear power plant under the aspect of ageing management. The main challenge of aging management is the determination of potential aging mechanism and to avoid systematically and effectively their damaging influences. In the course of the annual site inspections abnormalities at the lower side of the water-distribution channels of the cooling tower were detected, analysed, and repaired. The extraordinary high chlorine equivalent of the cooling water was identified as main reason of the damages located. Due to extensive infiltration into the concrete structure, chloride-induced corrosion generates a volume expansion of the reinforcement and thereby to a blast off of the concrete covering. According to the restoration concept, the damaged concrete was removed by maximum pressure water jet blasting; where necessary the reinforcement was retrofitted and a layered concrete substitution was applied by synthetic cement mortar. The realised procedures conserve the load bearing reinforcement only for a certain period, because the permanent chloride infiltration could not be stopped. Therefore, the structure has to be monitored permanently. (orig.)

  7. Basic regulations and standards for and performance of measurements in wet cooling towers; Norm-Grundlagen und praktische Durchfuehrung von Leistungsmessungen an Nasskuehltuermen

    Tesche, W. [Balcke-Duerr GmbH, Ratingen (Germany). Geschaeftsbereich Nasskuehlung


    Performance measurement in wet cooling towers is a process well covered and specified by national standards, which meanwhile have been harmonized. The European standard recently eleaborated by the cooling tower manufacturing firms that are members of the VDMA association reflects the state of the art and presents a regulatory framework for applications that has been well tuned to conditions met in practice. Evaluation of measurements relies on a comparative analysis of measured data with the cooling characteristics supplied by the manufacturer, either in the form of a diagram, a computer program, or as tabulated information. (orig./CB) [Deutsch] Leistungsmessungen am Nasskuehlturm sind in laenderspezifischen Normen genau spezifiziert. Die Normen haben sich mittlerweile angeglichen. Die von dem im VDMA zusammengeschlossenen Kuehlturmfirmen erarbeitete Euronorm zu diesem Thema spiegelt den aktuellen Stand in einer praxisnahen Durchfuehrungsverordnung wieder. Die Bewertung der Messung erfolgt im Vergleich mit der vor Messbeginn bekannten Kuehlcharakteristik, die entweder als Diagramm, Rechenprogramm oder zumindest als Tabelle vom Lieferanten erstellt wurde. (orig./GL)

  8. A short study on imaging new towers within the city. Students projects

    Ştefan Mihăilescu


    Full Text Available Present article aims to discuss project proposals on the thematic of new towers from the teaching point of view in architecture. The debate regarding high office buildings is released from its financial constrains mainly by the use of a theoretical process focused on conceptual approach regarding the urban integration of the design to better address the concerns of the relation between the new object and the city. Tutoring a complex architecture project involves lectures and interdisciplinary debates on the theme of constituted urban landscape and morphology, culture, identity, history, memory, place and people – all these being important for the project inception. Sustainable urban management and increased density could be very strong arguments in motivating the analysis of city tendencies, its evolution, nature and its structure. All these are only exercises which synthesize a wide range of knowledge from different domains, the lecture of the dedicated site, and the best answer to a specific brief considering a very complex context of future sustainable approach as the suitable attitude regarding the city and its built environment, as well as using the necessary skills and methods to stimulate creativity and research by design.

  9. Analysis on Application of Dry Cooling Tower for Freeze Protection in Winter%干式冷却塔冬季防冻的应用分析



    A mathematical model is presented to predict the condensing and frost formation characteristics on the heat transfer surfaces by simultaneously considering the condensing and frost layer. The model employs one-dimensional transient formulation based upon the local averaging technique, taking into account the variation of the frost density and thickness. The presented model is validated by comparing with the experimental data provided by the dry cooling tower manufacturer. It is found that, the model can predict the heat transfer performance of the dry cooling tower with accuracy within 2.19%. Dry cooling tower heat transfer performance at different air and water flow rates are predicted when it operates with water as heat transfer fluid during the winter period. The mathematical model and research results are helpful to the operation of such kind of dry cooling tower with water as the coolant during the winter period.%本文通过同时考虑冷凝和结霜层提出了一个能预测换热表面冷凝和结霜特性的数值模型。该模型采用基于局部平均的一维瞬态的数值方法,同时考虑了霜层密度和厚度的变化。该模型通过干式冷却塔制造商提供的实验数据来进行验证。模拟结果表明,该模型能有效预测干式冷却塔的传热性能,其精度在2.19%的范围内。同时计算了在冬季以水为传热工质情况下,不同空气和水流速的干式冷却塔的传热性能。本文的数值模型和研究结果将有助于以水为传热工质的干式冷却塔在冬季的运营和操作。

  10. 冷却塔风机水轮机拖动改造%Transformation of Water Turbine to Drive Cooling Tower Fan



    The throttling loss in circulative water system was studied and analyzed. Us-ing water turbine to replace motor by utilizing surplus water head in circulating water system to drive water turbine and in turn the cooling tower fan, achieving energy saving goal.%对循环水系统的节流损失进行了研究分析.利用循环水系统中的富余水头,推动水轮机转动,驱动冷却塔风机转动.从而由水轮机取代电机,达到节能目的.

  11. Application of Energy-saving Technology of No Filler Spray Cooling Tower with Free Electricity%无填料免电喷雾冷却塔节能技术的应用

    盖素霞; 刘立友; 王歌飞


    No filler spray cooling tower with free electricity is a new kind of industrial circulating water cooling equipment, and its cooling effect is more ideal than ordinary packing cooling tower. Its cooling capacity increases 8-10% than the conventional mechanical ventilation filler cooling tower, and it has lower requirements for the over affluent injecting distance of system, and saves more than 95%of the filler, and reduces the maintenance costs of the equipment. So it saves more energy tan the ordinary no filler spray cooling tower, saving above 70KW, so its energy-saving effect is obvious.%  无填料免电喷雾冷却塔是一种新型的工业循环水降温设备,它比普通的填料冷却塔降温效果理想,冷量比普通机械通风填料降温塔提高8-10%,免电喷雾冷却塔对系统的富裕扬程要求偏低,节省95%以上的填料,降低了设备的维修费用。比普通无填料喷雾冷却塔更节能,单塔节约70KW以上,节电效果明显。

  12. The WACMOS-ET project – Part 1: Tower-scale evaluation of four remote sensing-based evapotranspiration algorithms

    Michel, D.


    The WACMOS-ET project has compiled a forcing data set covering the period 2005–2007 that aims to maximize the exploitation of European Earth Observations data sets for evapotranspiration (ET) estimation. The data set was used to run 4 established ET algorithms: the Priestley–Taylor Jet Propulsion Laboratory model (PT-JPL), the Penman–Monteith algorithm from the MODIS evaporation product (PM-MOD), the Surface Energy Balance System (SEBS) and the Global Land Evaporation Amsterdam Model (GLEAM). In addition, in-situ meteorological data from 24 FLUXNET towers was used to force the models, with results from both forcing sets compared to tower-based flux observations. Model performance was assessed across several time scales using both sub-daily and daily forcings. The PT-JPL model and GLEAM provide the best performance for both satellite- and tower-based forcing as well as for the considered temporal resolutions. Simulations using the PM-MOD were mostly underestimated, while the SEBS performance was characterized by a systematic overestimation. In general, all four algorithms produce the best results in wet and moderately wet climate regimes. In dry regimes, the correlation and the absolute agreement to the reference tower ET observations were consistently lower. While ET derived with in situ forcing data agrees best with the tower measurements (R2 = 0.67), the agreement of the satellite-based ET estimates is only marginally lower (R2 = 0.58). Results also show similar model performance at daily and sub-daily (3-hourly) resolutions. Overall, our validation experiments against in situ measurements indicate that there is no single best-performing algorithm across all biome and forcing types. An extension of the evaluation to a larger selection of 85 towers (model inputs re-sampled to a common grid to facilitate global estimates) confirmed the original findings.

  13. The WACMOS-ET project – Part 1: Tower-scale evaluation of four remote sensing-based evapotranspiration algorithms

    D. Michel


    Full Text Available The WACMOS-ET project has compiled a forcing data set covering the period 2005–2007 that aims to maximize the exploitation of European Earth Observations data sets for evapotranspiration (ET estimation. The data set was used to run 4 established ET algorithms: the Priestley–Taylor Jet Propulsion Laboratory model (PT-JPL, the Penman–Monteith algorithm from the MODIS evaporation product (PM-MOD, the Surface Energy Balance System (SEBS and the Global Land Evaporation Amsterdam Model (GLEAM. In addition, in-situ meteorological data from 24 FLUXNET towers was used to force the models, with results from both forcing sets compared to tower-based flux observations. Model performance was assessed across several time scales using both sub-daily and daily forcings. The PT-JPL model and GLEAM provide the best performance for both satellite- and tower-based forcing as well as for the considered temporal resolutions. Simulations using the PM-MOD were mostly underestimated, while the SEBS performance was characterized by a systematic overestimation. In general, all four algorithms produce the best results in wet and moderately wet climate regimes. In dry regimes, the correlation and the absolute agreement to the reference tower ET observations were consistently lower. While ET derived with in situ forcing data agrees best with the tower measurements (R2 = 0.67, the agreement of the satellite-based ET estimates is only marginally lower (R2 = 0.58. Results also show similar model performance at daily and sub-daily (3-hourly resolutions. Overall, our validation experiments against in situ measurements indicate that there is no single best-performing algorithm across all biome and forcing types. An extension of the evaluation to a larger selection of 85 towers (model inputs re-sampled to a common grid to facilitate global estimates confirmed the original findings.

  14. An Analysis Method of Cooling Tower Supplemental Water Cost%冷却塔补水成本的一种分析方法



    The paper proposes the idea of converting the cooling tower supplement water of central air conditioning system to the corresponding electricity energy cost , as well as the concept of electrical equivalent price in water sup-plement cost.According to research , it is found that the water prices among different cities in China are quite dis-tinct, which suggests that the operation cost of cooling tower needs to be fully considered in air conditioning system selection.%本文提出了将集中空调系统冷却塔补水量换算成同等电费的电量来参与空调系统运行能耗成本计算的思路,提出了水的电当量概念。通过对比全国部分城市的水价,发现各城市之间水价差异大,认为在选择空调方案时,应充分重视冷却塔补水的运行成本。

  15. 采用风机盘管的办公建筑冷却塔供冷温度计算与分析%Analysis and Calculation of the cold Water Supply Temperature of Free Cooling by Cooling Tower in the Office Building with Fan Coil



    选取办公建筑内的一个计算单元为分析对象,建立了办公建筑的冷却塔供冷温度计算模型,分析了室内冷却塔供冷工况下冷源侧供冷温度的影响因素,提出了办公建筑冷却塔供冷系统运行的适宜运行工况。%Selected an calculation unit in the office building for analysis, Setup an calculation model for the cold water supply temperature of free cooling by cooling tower , analysis the influence factor of the cooling tower side to the old water supply temperature, proposed an suitable working condition for the free cooling by cooling tower.

  16. Reconstruction project of a bell tower of Joseph of Volokolamsk monastery: architectural, town-planning and structural aspects

    Tsvetkov Konstantin Aleksandrovich


    Full Text Available ASPECTS All over the world a lot of unique architectural monuments are lost according to different reasons. The role of cultural objects can hardly be overestimated and their total loss is irretrievable. Preservation of architectural monuments and complexity of their investigation and design solutions development depend on many factors: age of the monument, structural peculiarities, geographical position, their value as objects of cultural heritage, etc. The article offers the description of a reconstruction project of a bell tower in Joseph of Volokolamsk Monastery, which had been destructed in 1941. The bell tower in Joseph of Volokolamsk Monastery situated in Volokolamsk region of the Moscow Region near village Teryaevo is an outstanding example of the architecture and construction technologies of the 16th-17th centuries. The design group conducted extensive research, made a conclusion on the state of the surviving elements and offered several variants of bell tower reconstruction. It was decided to reconstruct the bell tower over the surviving first tier with transferring the loads to the new bearing structure. The first tier is being reconstructed and preserved.

  17. Field Plot Points for Devils Tower National Monument Vegetation Mapping Project

    National Park Service, Department of the Interior — Vegetation field plots at Devils Tower NM were visited, described, and documented in a digital database. The database consists of 2 parts - (1) Physical Descriptive...

  18. Experimental Research on Wet-cooling Tower Performance Under Cross-wind Conditions%侧风作用下火电厂冷却塔性能的实验研究

    刘剑涛; 曾宪平; 任建兴; 李芳芹; 杨涌文


    Cooling tower is one of the most important equipment of thermal power plant,the cooling performance of cooling towers will affect the efficiency and. safety of units. An experimental platform of cooling water system in power plant had been established to study the wet-cooling tower performance under cross-wind conditions. Researches show that with cross-wind velocity increasing,cooling temperature difference and cooling efficiency decrease first then increase at the knee point when the velocity value is 0.8m/s; the inlet wind at the windward side velocity increases, the leeward side of ventilation decreases. It also analysis the effect from the cross-wind to the performance of cooling towers with Froude number.%冷却塔是火电厂重要设备之一,冷却塔冷却性能的优劣直接影响机组效率与安全.通过建立火电厂冷却水系统实验平台,研究了侧风作用下冷却塔的冷却性能.研究发现:随着环境侧风的增加,冷却温差和效率呈先减小后增大的趋势,拐点风速值为0.8m/s;迎风面的进塔风速随之变大,背风面的通风量减小;并采用弗劳德准则数分析了环境侧风对冷却塔性能的影响.

  19. Design and application-specific design features of wet cooling towers and their impact on economic efficiency of the cooling system; Einfluss der Auslegung und Auswahl eines Nasskuehlturms auf die Wirtschaftlichkeit der Wasserrueckkuehlanlage

    Knopf, M. [GEA Management Gesellschaft fuer Waerme- und Energietechnik mbH, Nonnenhorn (Germany)


    Cooling towers and their required and appropriate design features continue to be an issue of debate among owners/operators, planning engineers and manufacturers. Often, the requirements and interests of the parties involved cannot be reconciled. Such incompatible requirements for instance are all as-low-as-possible requirements, relating to cold water temperatures - investment cost - performance requirements - noise emissions. Any requirement on its own can be met without problems, but their combination is the crucial aspect, and of course the compromise to be found has to be as near to an optimal solution as possible. Meeting the requirement of low cold water temperature for instance, with a close approach (a), implies that the cooling tower must be a large structure, needing high investment, which in turn can be justified if the design ensures a higher performance efficiency of the system or equipment to be cooled while reducing operating costs. (orig./CB) [Deutsch] Kuehltuerme und ihre Auslegung geben immer wieder Anlass zu Diskussionen zwischen Betreibern, Planern und Herstellern. Oft stehen sich Forderungen gegenueber, die miteinander nicht in Einklang zu bringen sind, wie z.B. - Kaltwassertemperatur so tief wie moeglich - Investitionskosten so niedrig wie moeglich - Leistungsbedarf so gering wie moeglich - Schallemission so wenig wie moeglich. Jede Forderung fuer sich betrachtet, kann erfuellt werden. Gefragt ist jedoch ein Kompromiss, der - bezogen auf die Gesamtanlage - ein Optimum darstellt. So bedeutet beispielsweise eine geringe Kaltwassertemperatur mit einem kleinen Kuehlgrenzabstand (a) die Wahl eines grossen Kuehlturms mit einer hohen Investitionssumme. Diese ist gerechtfertigt, wenn dadurch der Wirkungsgrad der zu kuehlenden Anlage oder Maschine vergroessert und die Betriebskosten damit verringert werden. (orig.)

  20. The Applicability Analysis about Free Cooling by Using Cooling Tower for Interior Zones of Large Commercial Building in Chengdu%冷却塔免费供冷在成都地区大型商业内区的适用性分析



    The theory and form of free cooling system are introduced. Through the analysis about cooling load of interior zones in winter, fan coil unit condition modification,the temperature of cooling tower supply and return water and outdoor climatic parameter of Chengdu, discussion the applicability of the technique in the area of large commercial area in Chengdu. Taking an example project of economic and suggestions for the design and operation are given.%简要介绍了冷却塔免费供冷的原理及形式,通过对冬季商业内区冷负荷,风机盘管的工况修正,冷却塔供回水温度及成都地区室外气象参数等因素的分析,探讨了该技术在成都地区大型商业内区的适用性。并结合实际工程案例进行了经济性分析并给出设计及运行建议。

  1. Development of Modular Spray-Cooled Assemblies for High Heat Fluxes Project

    National Aeronautics and Space Administration — This NASA SBIR project will develop modular spray-cooled assemblies that satisfy NASA power and mass budgets and can be scaled to cool multiple heat sources...

  2. Annual DOE active solar heating and cooling contractors' review meeting. Premeeting proceedings and project summaries



    Ninety-three project summaries are presented which discuss the following aspects of active solar heating and cooling: Rankine solar cooling systems; absorption solar cooling systems; desiccant solar cooling systems; solar heat pump systems; solar hot water systems; special projects (such as the National Solar Data Network, hybrid solar thermal/photovoltaic applications, and heat transfer and water migration in soils); administrative/management support; and solar collector, storage, controls, analysis, and materials technology. (LEW)

  3. Baca geothermal demonstration project baseline ecosystem studies of cooling tower emission effects

    Leitner, P.; Osterling, R.; Price, D.; Westermeier, J.


    Results of baseline studies for boron, arsenic, mercury, and fluorine in vegetation and soil near the Baca Geothermal Demonstration Power Plant are provided for the 1980 sampling season. Preliminary results of visual vegetation assessments and population density studies of soil invertebrate fauna are also provided. Foliage samples were collected for chemical analysis on a total of 17 plots on 5 transects. Two to five plant species were sampled at each plot. Samples were collected in June-July and September. Soil samples were collected at each plot during September. Visual vegetation inspections were conducted along each transect. Eighty-eight soil samples were collected for soil invertebrate studies. Boron, arsenic, mercury, and fluorine levels in vegetation were within normal range for natural vegetation and crops. Concentrations of soil arsenic and mercury were comparable to foliage concentrations. Boron concentrations were lower in soil than in foliage, whereas soil fluorine concentrations were considerably higher than foliage concentrations. With the exception of heavy insect infestations in June-July, no vegetation abnormalities were noted. Preliminary soil invertebrate analysis indicated an overall arthropod density of approximately 100,000/m/sup 2/ which appears within the normal range encountered in forest and meadow soil.

  4. Clean cooling; Saubere Kuehlung



    The round hybrid cooling towers which Balcke-Duerr GmbH is currently building for the 550-MW-IGCC-power-station of a refinery project on Sardinia have to meet particularly stringent requirements as seawater is used for cooling. The advantages are: Avoidance of visible plume with minimal energy consumption, optimal plume exit velocity and discharge, greatest possible stability of the plume column, avoidance of interference and recirculation, high operating reliability of the cooling tower. (orig.) [Deutsch] Derzeit werden die Kuehltuerme fuer ein 550-MW-IGCC-Kraftwerk einer Raffinierie auf Sardinien errichtet. Die Anforderungen an die Technik sind hoch, denn gekuehlt wird mit Seewasser. Zum Einsatz kommen Hybridrundkuehltuerme der Balcke-Duerr GmbH, Ratingen. Damit setzt das Unternehmen diesen Typ erstmals ausserhalb von Deutschland ein. (orig.)

  5. Tower Camera

    Oak Ridge National Laboratory — The tower camera in Barrow provides hourly images of ground surrounding the tower. These images may be used to determine fractional snow cover as winter arrives, for...

  6. Application of CAD Secondary Development in Cooling Tower Software Development%CAD二次开发在冷却塔软件开发中的应用

    郑鸿飞; 王小松; 毛国辉


    介绍了利用ObjectARX. NET对AutoCAD二次开发的基本技术的概述。针对ObjectARX. NET开发工具的特点,介绍了CAD二次开发对图形数据库的访问技术,着重探讨了动态块技术在CAD二次开发中的应用。程序通过识别块体参数名修改相应的参数值实现了对动态块参照的修改,在参数化数据文件的组织和读取中,根据信息参数化的思想组织数据文件。程序采用基于关键字的方式读取相关数据便于数据文件进行扩充,并把这些技术应用到冷却塔软件开发出图程序中,实现冷却塔程序参数化和快速化设计,提高设计人员的工作效率。%Introduce the basic technique of CAD secondary development on the basis of ObjectARX. NET. For the features of Object-ARX. NET development tool,introduce the technique of using CAD secondary development to access to graphical database,especially ex-plore the application of dynamic blocks in CAD secondary development. The program can recognize the name of dynamic block and mod-ify the corresponding parameter value,thus modifying the reference of dynamic block. The program organizes data files according to the thinking of transferring information to parameters,and reads corresponding data through keywords,making it convenient to extend the da-ta files. All these methods and techniques can be applied in cooling tower software to develop the diagram program. Thus designers can work efficiently as the realization of cooling tower software program parametric and rapid design.

  7. Hybrid Cooling Loop Technology for Robust High Heat Flux Cooling Project

    National Aeronautics and Space Administration — Advanced Cooling Technologies, Inc. proposes to develop a hybrid cooling loop technology for space thermal control. The proposed technology combines the high heat...

  8. Hybrid Cooling Loop Technology for Robust High Heat Flux Cooling Project

    National Aeronautics and Space Administration — Advanced Cooling Technologies, Inc. (ACT) proposes to develop a hybrid cooling loop and cold plate technology for space systems thermal management. The proposed...

  9. Analysis on anti-erosion problems of exhaust cooling tower steel reinforced concrete structure of coal-fired power plants%燃煤火电厂排烟冷却塔钢筋混凝土结构防腐蚀问题



    The paper studies the erosion mechanism of exhaust cooling tower,puts forward major steel reinforced concrete structure anti-erosion methods of exhaust cooling tower,and achieves the effect of improving concrete durability and anti-erosion performance of exhaust cooling tower.%对排烟冷却塔混凝土腐蚀机理进行了研究,介绍了排烟冷却塔钢筋混凝土结构防腐蚀的方法,达到了提高排烟冷却塔混凝土耐腐蚀性和耐久性的效果。

  10. Prevention of Legionella in cooling towers and evaporation condensers. Avoiding risks by good practices; Preventie Legionella bij koeltorens en verdampingscondensors. Risico's vermijden door Good Practices te gebruiken

    Blok, H. (ed.)


    Risks of evaporation coolers and more in particular cooling towers with a closed circuit and energy efficient evaporation condensors, are very low. Well-maintained installations are practically risk-free. Cooling towers and evaporation coolers need to be cleaned on a regular basis and require anti-bacteria treatment. In this article recommendations are formulated. [Dutch] Risico's die kleven aan verdampingskoelers en in het bijzonder aan de koeltorens met een gesloten circuit en de verdampingscondensors, welke een aanzienlijke energiebesparing opleveren, zijn zeer laag en goed onderhouden installaties vormen praktisch geen enkel risico. Koeltorens en verdampingscondensors moeten regelmatig gereinigd worden en behoeven een antibacteriele behandeling. In dit artikel worden hiervoor enkele aanbevelingen gegeven.

  11. The GEWEX LandFlux project: evaluation of model evaporation using tower-based and globally gridded forcing data

    McCabe, Matthew


    Determining the spatial distribution and temporal development of evaporation at regional and global scales is required to improve our understanding of the coupled water and energy cycles and to better monitor any changes in observed trends and variability of linked hydrological processes. With recent international efforts guiding the development of long-term and globally distributed flux estimates, continued product assessments are required to inform upon the selection of suitable model structures and also to establish the appropriateness of these multi-model simulations for global application. In support of the objectives of the Global Energy and Water Cycle Exchanges (GEWEX) LandFlux project, four commonly used evaporation models are evaluated against data from tower-based eddy-covariance observations, distributed across a range of biomes and climate zones. The selected schemes include the Surface Energy Balance System (SEBS) approach, the Priestley–Taylor Jet Propulsion Laboratory (PT-JPL) model, the Penman–Monteith-based Mu model (PM-Mu) and the Global Land Evaporation Amsterdam Model (GLEAM). Here we seek to examine the fidelity of global evaporation simulations by examining the multi-model response to varying sources of forcing data. To do this, we perform parallel and collocated model simulations using tower-based data together with a global-scale grid-based forcing product. Through quantifying the multi-model response to high-quality tower data, a better understanding of the subsequent model response to the coarse-scale globally gridded data that underlies the LandFlux product can be obtained, while also providing a relative evaluation and assessment of model performance.

    Using surface flux observations from 45 globally distributed eddy-covariance stations as independent metrics of performance, the tower-based analysis indicated that PT-JPL provided the highest overall statistical performance (0.72; 61 W m−2; 0.65), followed

  12. The GEWEX LandFlux project: evaluation of model evaporation using tower-based and globally-gridded forcing data

    McCabe, Matthew


    Determining the spatial distribution and temporal development of evaporation at regional and global scales is required to improve our understanding of the coupled water and energy cycles and to better monitor any changes in observed trends and variability of linked hydrological processes. With recent international efforts guiding the development of long-term and globally distributed flux estimates, continued product assessments are required to inform upon the selection of suitable model structures and also to establish the appropriateness of these multi-model simulations for global application. In support of the objectives of the GEWEX LandFlux project, four commonly used evaporation models are evaluated against data from tower-based eddy-covariance observations, distributed across a range of biomes and climate zones. The selected schemes include the Surface Energy Balance System (SEBS) approach, the Priestley-Taylor Jet Propulsion Laboratory (PT-JPL) model, the Penman-Monteith based Mu model (PM-Mu) and the Global Land Evaporation: the Amsterdam Methodology (GLEAM). Here we seek to examine the fidelity of global evaporation simulations by examining the multi-model response to varying sources of forcing data. To do this, we perform parallel and collocated model simulations using tower-based data together with a global-scale grid-based forcing product. Through quantifying the multi-model response to high-quality tower data, a better understanding of the subsequent model response to coarse-scale globally gridded data that underlies the LandFlux product can be obtained, while also providing a relative evaluation and assessment of model performance.

    Using surface flux observations from forty-five globally distributed eddy-covariance stations as independent metrics of performance, the tower-based analysis indicated that PT-JPL provided the highest overally statistical performance (0.72; 61 W m−2; 0.65), followed closely by GLEAM (0.68; 64 W m

  13. The GEWEX LandFlux project: evaluation of model evaporation using tower-based and globally-gridded forcing data

    McCabe, M. F.; Ershadi, A.; Jimenez, C.; Miralles, D. G.; Michel, D.; Wood, E. F.


    Determining the spatial distribution and temporal development of evaporation at regional and global scales is required to improve our understanding of the coupled water and energy cycles and to better monitor any changes in observed trends and variability of linked hydrological processes. With recent international efforts guiding the development of long-term and globally distributed flux estimates, continued product assessments are required to inform upon the selection of suitable model structures and also to establish the appropriateness of these multi-model simulations for global application. In support of the objectives of the GEWEX LandFlux project, four commonly used evaporation models are evaluated against data from tower-based eddy-covariance observations, distributed across a range of biomes and climate zones. The selected schemes include the Surface Energy Balance System (SEBS) approach, the Priestley-Taylor Jet Propulsion Laboratory (PT-JPL) model, the Penman-Monteith based Mu model (PM-Mu) and the Global Land Evaporation: the Amsterdam Methodology (GLEAM). Here we seek to examine the fidelity of global evaporation simulations by examining the multi-model response to varying sources of forcing data. To do this, we perform parallel and collocated model simulations using tower-based data together with a global-scale grid-based forcing product. Through quantifying the multi-model response to high-quality tower data, a better understanding of the subsequent model response to coarse-scale globally gridded data that underlies the LandFlux product can be obtained, while also providing a relative evaluation and assessment of model performance. Using surface flux observations from forty-five globally distributed eddy-covariance stations as independent metrics of performance, the tower-based analysis indicated that PT-JPL provided the highest overally statistical performance (0.72; 61 W m-2; 0.65), followed closely by GLEAM (0.68; 64 W m-2; 0.62), with values in

  14. The GEWEX LandFlux project: evaluation of model evaporation using tower-based and globally gridded forcing data

    McCabe, M. F.; Ershadi, A.; Jimenez, C.; Miralles, D. G.; Michel, D.; Wood, E. F.


    Determining the spatial distribution and temporal development of evaporation at regional and global scales is required to improve our understanding of the coupled water and energy cycles and to better monitor any changes in observed trends and variability of linked hydrological processes. With recent international efforts guiding the development of long-term and globally distributed flux estimates, continued product assessments are required to inform upon the selection of suitable model structures and also to establish the appropriateness of these multi-model simulations for global application. In support of the objectives of the Global Energy and Water Cycle Exchanges (GEWEX) LandFlux project, four commonly used evaporation models are evaluated against data from tower-based eddy-covariance observations, distributed across a range of biomes and climate zones. The selected schemes include the Surface Energy Balance System (SEBS) approach, the Priestley-Taylor Jet Propulsion Laboratory (PT-JPL) model, the Penman-Monteith-based Mu model (PM-Mu) and the Global Land Evaporation Amsterdam Model (GLEAM). Here we seek to examine the fidelity of global evaporation simulations by examining the multi-model response to varying sources of forcing data. To do this, we perform parallel and collocated model simulations using tower-based data together with a global-scale grid-based forcing product. Through quantifying the multi-model response to high-quality tower data, a better understanding of the subsequent model response to the coarse-scale globally gridded data that underlies the LandFlux product can be obtained, while also providing a relative evaluation and assessment of model performance. Using surface flux observations from 45 globally distributed eddy-covariance stations as independent metrics of performance, the tower-based analysis indicated that PT-JPL provided the highest overall statistical performance (0.72; 61 W m-2; 0.65), followed closely by GLEAM (0.68; 64 W m-2

  15. Demonstration and Validation of Corrosion-Mitigation Technologies for Mechanical Room Utility Piping and Cooling-Tower Pumps


    ready to install using standard scissors. TBD Manufactured from silicone impregnated woven fiberglass cloth. Fits standard pipe and tubing sizes...this project. Furthermore, less work is involved in cleaning and repainting joints than replacing them, which is now estimated at $6,000,000

  16. 国电库车发电厂空冷塔X柱及筒壁施工工艺%Construction Craft of the Air-cooling Tower X Column and Cylinder Wall in Guodian Kuche Power Plant


    The Guodian Kuche power plant air-cooling tower is the largest air-cooling tower in Xinjiang, the height of air-cooling tower X pil ar is 26m, section is big and inclined 70 DEG, supporting rack erection is complex; the height of cylin-der wal is 157 m, vertical transportation difficulty is big, quan-tities is large, radius is large, horizontal transportation has gr-eat dif iculty. We use the advanced construction technology, improve the efficiency of work.%  国电库车发电厂空冷塔为全疆最大的空冷塔,空冷塔 X 支柱高度26 m、截面大并倾斜70°,支撑排架搭设复杂;筒壁高度157m、垂直运输难度大、工程量大、半径大、水平运输难度大。我们采用了先进的施工工艺,提高了工作效益。

  17. Numerical simulation on internal and external flow field of a SCAL indirect air cooling tower%SCAL型间接空冷塔内外流场数值模拟

    田松峰; 柴艳琴; 向同琼; 周广沙


    根据某SCAL型自然通风空气冷却塔(空冷塔)散热管束的实际尺寸和冷却三角的布置方式,对塔底换热单元建立了几何模型,并基于 RNG k-ε紊流模型和多孔介质模型,对塔内外流场进行了三维数值模拟,探究了环境条件对其运行特性的影响。研究结果表明:随着环境风速的增加,空冷塔迎风面进口风速逐渐增加,而侧风面和背风面的进口风速则呈下降趋势,且该趋势随温度的上升愈加明显;空冷塔的通风量和塔出口速度随环境风速的增加先增大后减小,且在风速为2m/s 时,其通风量和出口速度最大。%According to the actual size of cooling tube bundle and the arrangement of cooling trian-gle of a surface condenser aluminum exchangers (SCAL)natural draft cooling tower,the geomet-ric model of heat transfer elements at the tower bottom was established.On the basis of the RNG k-εturbulence model and porous medium model,three-dimensional numerical simulation was car-ried out for the inner and external flow field of the air cooling tower,to investigate the influence of environmental conditions on the tower's operation performance.The results show that,with an increase in ambient wind speed,the inlet air speed at windward side of the tower increases gradu-ally,while that at crosswind side and lee side decreases and tends to be obvious;the tower ventila-tion rate and outlet air speed increases at first and then decreases,and their maximum values ap-pear when the wind speed is 2 m/s.

  18. 清远市空调冷却塔水军团菌污染状况调查%The investigation of Legionella pollution with cooling tower water of air conditioning in Qingyuan city

    黄惠兴; 李桂霞; 王平原; 禤汝流; 徐国洪; 陈丽萍


    Objective:To understand the detection of Legionella in public place in Qingyuan city and the relation between the result with the consecutively using time and environment including the water temperature of cooling tower, relative humidity inside cooling tower, pH value, chlorine residual, identification and typing of Leginoella.Methods: Water samples were collected from 32 public places in Qingyuan following the health specification of central air conditioning ventilating system in public places.Then the samples for Legionella detection.Results: The isolating rate of Legionella is 51.42% in public places in Qingyuan.There was relation between isolating rate and environment including the water temperature of cooling tower, relative humidity, pH value.There were six serotypes of Legionella isolated in Qingyuan, including serotypes 1,2, 3, 6, 7 and 10, of which the most frequent is serotype 1.Conclution: The Legionella pollution with cooling tower water of air conditioning in Qingyuan city is in a serious situtation.Measures should be taken to strengthen the monitoring of the water of cooling tower.%目的:了解清远市区空调冷却塔水军团菌的检出情况、军团菌检出与环境(冷却塔水温度、冷却塔内相对湿度、pH值、余氯含量)和连续使用时间的关系以及军团菌的分型、鉴定.方法:根据随机抽取清远市区公共场所32家,对其冷却塔水进行军团菌检测.结果:清远市空调冷却塔水军团菌检出率为51.42%,军团菌的检出与环境(冷却塔水温度、冷却塔内相对湿度、pH值)有关,军团菌菌型为嗜肺军团菌1型、2型、3型、6型、7型和10型,其中1型为优势菌株.结论:清远市区空调冷却塔水军团菌污染严重,应加强冷却塔水监测.

  19. 填料加盘管型闭式冷却塔的性能试验研究%Experimental research on performance of closed cooling tower with packing material and coil

    谢卫; 周亚素; 张恒钦


    Through designing and constructing closed cooling tower with packing material and coil, its performance was tested. The results showed that, for the closed cooling tower with packing material and coil which had fixed structure and design parameters, air wet bulb temperature and air flow rate had the most significant influence on its cooling performance, cooling water flow rate and inlet temperature had a great influence, the influence of spray density was essentially unchanged after it had achieved the best value, and air dry bulb temperature had only a minor influence. Due to the addition of packing material, the best spray density of closed cooling tower with packing material and coil was relatively small, which could be set to any value between 0.025 and 0.035 kg/(m·s).%通过设计和搭建填料加盘管型闭式冷却塔对其进行了性能测试.试验结果表明,对于结构和设计参数确定的填料加盘管型闭式冷却塔,空气湿球温度和空气流量对其冷却性能的影响最为显著,冷却水流量和进口温度则有较大影响,而喷淋密度在达到最佳值后对其冷却性能的影响基本保持不变,空气干球温度只有较小影响.由于填料的加入,填料加盘管型闭式冷却塔的最佳喷淋密度相对偏小,可以在0.025 ~ 0.035 kg/(m·s)之间取值.

  20. 一种提高喷雾通风冷却塔换热效果的方法%A Method for Improving Heat Transfer in Spray Cooling Tower

    葛海标; 柴才明; 祝易松


    Cooling tower is the core equipment in the circulative water system of CDQ and its performance directly influences the power output and water consumption rate in the coke dry quenching system. Problems such as poor heat transfer, serious wall flow and tower body vibration occurred during operation of the spray cooling tower at the coke dry quench-ing system of Masteel. In the paper the basic principle of spray cooling tower was analyzed, a mathematical model was established and numerical simulations were carried out with fluid dynamics calculation software to found out the direct relationship between poor transfer and wall flow. A solution to increase the injecting angle and reduce wall flow by injector hole shrinkage was finally put forward, which effectively improved heat transfer.%冷却塔是干熄焦循环水系统的核心设备,其换热效果直接影响干熄焦发电量和耗水率。马钢干熄焦系统中应用的喷雾通风冷却塔在使用中出现换热效果不佳、壁流严重以及塔体振动等问题。分析了喷雾通风冷却塔的基本原理,建立其物理模型,并使用计算流体力学软件进行数值计算,找出了其换热效果差与壁流有直接的关系。最后提出了一种解决方案,通过对喷嘴缩径提高射流角度,减少了壁流,从而有效地提高了换热效果。

  1. Effect of chlorine and temperature on free-living protozoa in operational man-made water systems (cooling towers and hot sanitary water systems) in Catalonia.

    Canals, Oriol; Serrano-Suárez, Alejandra; Salvadó, Humbert; Méndez, Javier; Cervero-Aragó, Sílvia; Ruiz de Porras, Vicenç; Dellundé, Jordi; Araujo, Rosa


    In recent decades, free-living protozoa (FLP) have gained prominence as the focus of research studies due to their pathogenicity to humans and their close relationship with the survival and growth of pathogenic amoeba-resisting bacteria. In the present work, we studied the presence of FLP in operational man-made water systems, i.e. cooling towers (CT) and hot sanitary water systems (HSWS), related to a high risk of Legionella spp. outbreaks, as well as the effect of the biocides used, i.e. chlorine in CT and high temperature in HSWS, on FLP. In CT samples, high-chlorine concentrations (7.5 ± 1.5 mg chlorine L(-1)) reduced the presence of FLP by 63.8 % compared to samples with low-chlorine concentrations (0.04 ± 0.08 mg chlorine L(-1)). Flagellates and amoebae were observed in samples collected with a level of 8 mg chlorine L(-1), which would indicate that some FLP, including the free-living amoeba (FLA) Acanthamoeba spp., are resistant to the discontinuous chlorine disinfection method used in the CT studied. Regarding HSWS samples, the amount of FLP detected in high-temperatures samples (53.1 ± 5.7 °C) was 38 % lower than in low-temperature samples (27.8 ± 5.8 °C). The effect of high temperature on FLP was chiefly observed in the results obtained by the culture method, in which there was a clear reduction in the presence of FLP at temperatures higher than 50 °C, but not in those obtained by PCR. The findings presented here show that the presence of FLP in operational man-made water systems should be taken into account in future regulations.

  2. Simulación de una Torre de Enfriamiento Mecánica Comparada con Curvas Experimentales Simulation of a Mechanical Cooling Tower Compared with Experimental Curves

    Jader D Alean


    Full Text Available El objetivo del trabajo es modelar y simular una torre de enfriamiento mecánica forzada a escala piloto. Las variables físicas se correlacionaron a partir de la transferencia de calor y materia y los resultados de la simulación son analizados mediante graficas que muestran la variación de la humedad, flujo de agua, calor latente, calor sensible, calor total, temperatura del agua y del aire. El coeficiente de transferencia de materia se obtuvo a partir de los datos experimentales y la solución numérica del modelo se obtuvo con el método Runge-Kutta en Matlab. La verificación de los resultados fue realizada, comparando las curvas simuladas con las curvas experimentales. Se concluye que la cercanía entre las curvas depende del coeficiente de transferencia de materia.The objective of this work was the modeling and simulation of a pilot-scale mechanical enforced cooling tower. The physical variables were correlated from the heat and mass transfer and the simulation results were analyzed using graphs showing the change in humidity, water flow, latent heat, heat sensitive, total heat, water temperature and air. The mass transfer coefficient was obtained from experimental data and the numerical solution of the model was obtained using Runge-Kutta method in Matlab. Comparison between stimulation results and experimental data was done. It is concluded that the shape of the curves and the deviations of the simulated results depend on the mass transfer coefficient.

  3. Water tower


    The water tower, being built on the highest point of the site, 460.5 m above the sea level. The tank will hold 750 m3 of water, and the tower will be topped by a knob which can serve as a geological survey reference mark.

  4. Characteristic Study on Cool Storage in Transition Period of Cooling Tower-Ground Coupled Heat Pump in Hot-summer and Cold-winter Zone%夏热冬冷地区冷却塔—土壤耦合热泵过渡季蓄冷特性研究

    谢莉; 刘金祥; 刘凯


    This paper proposes a soil cool storage model for cooling tower-ground coupled heat pump in transition period based on cooling and heating load characteristics in hot-summer and cold-winter zone,establishes a simulation model for the soil cool storage system of cooling tower-ground coupled heat pump in transition period by means of software TRNSYS,conducts working condition simulation analysis of the two main influencing factors of the model regarding soil cool storage in transition period and proposes a control strategy regarding soil cool storage in transition period for cooling tower-ground coupled heat pump.Besides,this paper also strives to explore an effective method to relieve yearly thermal imbalance of ground-source heat pump in hot-summer and cold-winter zone and improve system operation efficiency based on the researches above.%本文针对夏热冬冷地区冷热负荷特性,提出了冷却塔—土壤耦合热泵过渡季土壤蓄冷模式,采用软件TRNSYS建立了冷却塔—土壤耦合热泵过渡季土壤蓄冷系统仿真模型,并利用该模型针对过渡季土壤蓄冷的两个主要影响因素进行了工况模拟分析,,在此基础上提出了冷却塔—土壤耦合热泵过渡季节土壤蓄冷的控制策略.本文力图通过上述研究探索出缓解夏热冬冷地区土壤源热泵系统全年热失衡问题、提高该系统运行效率的有效途径.

  5. LOX/Methane Regeneratively-Cooled Rocket Engine Development Project

    National Aeronautics and Space Administration — Design, build, and test a 5,000 lbf thrust regeneratively cooled combustion chamber at JSC for a low pressure liquid oxygen/methane engine. The engine demonstrates...

  6. Ultralightweight, Regeneratively Cooled Combustion Chamber for Mars Ascent Vehicles Project

    National Aeronautics and Space Administration — We propose a high-pressure, regeneratively-cooled combustion chamber that uses novel material selection for extreme reductions in mass. These materials are...

  7. Hybrid Cooling for Geothermal Power Plants: Final ARRA Project Report

    Bharathan, D.


    Many binary-cycle geothermal plants use air as the heat rejection medium. Usually this is accomplished by using an air-cooled condenser (ACC) system to condense the vapor of the working fluid in the cycle. Many air-cooled plants suffer a loss of production capacity of up to 50% during times of high ambient temperatures. Use of limited amounts of water to supplement the performance of ACCs is investigated. Deluge cooling is found to be one of the least-cost options. Limiting the use of water in such an application to less than one thousand operating hours per year can boost plant output during critical high-demand periods while minimizing water use in binary-cycle geothermal power plants.

  8. Virtueller Tower

    Fürstenau, Norbert


    Es wird ein Überblick über den Stand der Forschung und Entwicklung zum Remote Tower Experimentalsystem gegeben, des im Rahmen des DLR-Projekts RapTOr am Forschungsflughafen Braunschweig aufgebaut wird.

  9. Project EXCEL: San Francisco Hilton and Towers, Stewarding Department. English Communication, Module 1.

    Career Resources Development Center, Inc., San Francisco, CA.

    Project EXCEL is a federally-funded workplace literacy program involving hotel enterprises in the San Francisco (California) Bay area. Its focus is on identification and instruction of literacy skills essential to job success for limited-English-proficient (LEP) workers. Training is intended to enable employees to understand written work orders,…

  10. The Contractor Perception Towers Industrialised Building System Risk in Construction Projects in Malaysia

    Salihudin Hassim


    Full Text Available The use of IBS (Industrialised Building System has attracted a lot of countries like Singapore, Sweden, Germany, Japan and the United Kingdom. This system can replace the conventional building system which is labour oriented. However, since the first project of IBS in year 1964 till today, IBS in Malaysia is not well accepted by the construction parties because of failure to adequately deal with risks in the IBS projects. To address this matter, this study had identified the risks faced by contractor in IBS construction projects. The risk identification techniques used were brainstorming, analysis of journal and conference papers and discussion with practitioners and data were collected by a questionnaire survey on contractors. It was found that there are twelve major risks in construction using IBS which are; acts of God, change in work and defective design, changes in government regulation, contractor competence, delayed payment and resolving contractual issues, financial failure-any party, labour and equipment productivity, labour, equipment and material availability, quality of work, safety, site access/right of way and suppliers/manufacturers poor performance. Therefore, it is hoped that the finding of this research could assist Malaysian contractors in making risk management planning besides improving decisions making to achieve project.

  11. 快速喷雾结冰技术在循环冷却水塔中的应用%Application of Rapid Spray-Freezing Technology in the Anti-icing of Circulating Cooling Towers

    郭民臣; 马英; 梅勇; 陈文飞; 王卜平


    针对我国北方地区发电厂中冷却水塔冬季防冻问题,提出了循环冷却水塔快速喷雾结冰技术.通过与悬挂挡风板冷却塔的对比,论证了快速啧雾结冰技术在优化调节循环水温度及循环冷却水塔防寒防冻方面的明显优势.结果表明:采用快速喷雾结冰技术能够使冷却水塔在严寒季节或天气情况突变时安全运行,可以使机组循环水温度随着环境温度高低和机组负荷大小而自动调整,以达到最佳值,从而提高了机组的经济性.%To realize the anti-icing purpose for power plant cooling towers in northern China, a rapid spray- freezing technology is proposed. By comparing the cooling tower adopting the rapid spray-freezing technol- ogy with that protected by suspension windshields, the former one is found to be more superior to the lat- ter one in the adjustment of circulating water temperature and in the anti-icing protection of cooling tower. Results show that with the rapid spray-freezing technology, the circulating water temperature may be ad- justed automatically to optimal data according to the variation of both the environmental temperature and the unit load, which therefore makes it possible for the unit to safely and economically operate during days of bitter cold or with sudden change in weather.

  12. Reinforced concrete corrosion: application of Bayesian networks to the risk management of cooling towers in nuclear plants; Corrosion du beton arme: application des reseaux bayesiens a la gestion du risque des aerorefrigerants des centrales nucleaires

    Capra, B.; Le Drogo, J.; Wolff, V. [OXAND S.A., 77 - Avon (France)


    Degradation modeling of concrete structures uses uncertain variables and leads, using reliability assessment, to time dependant evolution of failure probabilities. However, only few data are generally available to feed models leading to two types of uncertainties: an intrinsic one depending on the modeled phenomena and one related to the precision of the measurements. Each new data available is a piece of information which allows updating the initial prediction. In this article, an example of updating process, based on a Bayesian network, is presented and applied on the corrosion risk of a cooling tower in a nuclear plant. (authors)

  13. 公共场所中央空调冷却塔水军团菌生态学研究%Study on ecology of legionella in cooling tower water of air-conditioning systems in public place

    林朝; 宋晓荷


    Objective: To explore the ecological distributional characteristics of legionella in cooling tower water of air - conditioning systems. Methods: The distribution of legionella in cooling tower water of air - conditioning systems in public place in Xiangshan was investigated through separation culture. Results: The detection rate of legionella was increased in summer and autumn, and decreased to zero in winter and spring. The positive rates from different public places were not concordant, with 78.95% and 50.70% in hospital and guesthouse separately. The bacterium type was varied, Lp 1 with a percentage of 68.7% was the predominant type. Detection rate was also related to base type of cooling tower, because it was only found to be positive in platform type. Conclusion: The growth and decline of legionella in cooling tower water of air - conditioning systems was related to season, and the bacterium type was varied. The air - conditioning systems with platform base in hospital and guesthouse should be the key site for monitoring.%目的:了解中央空调冷却塔水军团菌生态学分布特征.方法:采用分离培养方法,对象山县公共场所中央空调冷却塔水中的军团菌分布进行研究.结果:夏秋季军团菌检出率高,冬春季节未能检出.不同场所军团菌检出率不同,医院、宾馆酒店阳性率分别达78.95%、50.70%.菌型分布为多样性,主要为嗜肺军团菌Lp1型,占68.7%.检出率还与中央空调冷却塔基座类型相关,漏斗型未检出军团菌,只有平台型检出军团菌.结论:中央空调冷却塔水中军团菌消长有季节性,菌型分布多样性,以医院、宾馆等公共场所,冷却塔基座为平台型的中央空调为重点.

  14. Mechanical Properties of UHPFRC Joint for FORIDA Wind Turbine Tower

    Sørensen, Eigil Verner

    FORIDA Development, Vestas and Aalborg University are currently undertaking the project “FORIDA Hybrid Towers – The towers for next generation of wind turbines”, aiming to develop a new wind turbine tower structure (The FORIDA Tower) for very tall turbines. The tower is going to be a hybrid...... of materials combining steel and Ultra High Performance Fibre Reinforced Concrete (UHPFRC), applied as precast units. The FORIDA Tower is competitive regarding price, design, flexibility and durability....

  15. 无锡市2009年部分冷却塔水军团菌污染状况调查%Survey on Contamination of Legionella Bacteria in Water of Cooling Towers in Wuxi in 2009

    周伟杰; 吴湧兴; 肖勇


    目的 了解无锡市不同类型场所冷却塔水中军团菌污染状况和血清型别.方法 2009年按照无锡市地理分布抽取32家公共场所和8家工厂作为监测点,共抽取冷却塔水89份,按照卫生部附录B"空调系统军团菌的检验分析方法"进行检测.结果 89份冷却塔水军团菌检出率达26.97%(24/89),阳性率以宾馆和医院为高,分别为33.33%(8/24)和33.36%(4/11).军团菌血清型以LP1和LP6为主,分别占54.2%(13/24)和29.2%(7/24).冷却塔水消毒与不消毒、有无藻类生长军团菌检出差异有统计学意义.结论 无锡市不同场所冷却塔水中存在军团菌的污染,军团菌生长可能与冷却塔水不消毒、有藻类生长有关,可作为控制冷却水军团菌的依据.%Objective To explore the contamination status and serological typing in water of various cooling towers in Wuxi. Methods Legionella was detected in cooling water from 32 public places and 8 factories in Wuxi in 2009. There were 89 samples total. Legionella was tested according to “Central Air Conditioning Ventilation System Hygiene Norms of Public Health Appendix B”. Results The detection rate of legionella in water of cooling towers was 26.97% (24/89). The positive rate was the highest in cooling water of hotels and hospitals, which was 33.33% (8/24) and 33.36(4/11 ), respectively. The Lp1 and Lp6 were the main serotypes, accounted for 54.2% ( 13/24)and 29.2% (7/24), respectively. There were statistically significant differences in the positive rate of legionella between disinfected and non - disinfected water of cooling towers and between water with or without colonized algae. Conclusions The water of cooling towers in Wuxi was contaminated severely. The proliferation of legionella is presumed due to unsatisfactory disinfection and colonized algae. The results provide the evidence for control of legionella in water of cooling tower.

  16. TacTower

    Rasmussen, Majken Kirkegaard; Jürgensen, Christine


    Learning from the multiplayer interaction in sports, we describe our project TacTower; a flexible system for professional elite handball players to train game perception and kinesthetic em- pathy. The design is founded in ideas of Collective Interaction and qualities that is inherent in sport...

  17. Assessment of requirements for dry towers

    Peterson, D E; Sonnichsen, J C


    The regional limitations of surface water supplies in the U.S. were assessed with respect to the consumptive use requirements of wet cooling towers. The study simulated unit consumptive use factors by region, assessed regional water supplies, and examined electric load projections through 2000 A.D. to ascertain where and when water limitations may occur and, therefore, where dry cooling may be required. It was concluded that the cooling water supply situation in the United States through the year 2000 is adequate in most areas, but is uncertain over much of the Southwest. The uncertainty is related to increasing competition for the available supplies and to potential Federal and/or State policy decisions that may have a significant effect on power plant cooling. Limitations on coastal siting, seismic zone constraints, and state constraints on the purchase and transfer of water rights from other uses to cooling supply have the potential of bringing wet/dry or dry cooling into relatively common use in the 1990's. (LCL)

  18. High Performance Mars Liquid Cooling and Ventilation Garment Project

    Terrier, Douglas; Clayton, Ronald; Whitlock, David; Conger, Bruce


    EVA space suit mobility in micro-gravity is enough of a challenge and in the gravity of Mars, improvements in mobility will enable the suited crew member to efficiently complete EVA objectives. The idea proposed is to improve thermal efficiencies of the liquid cooling and ventilation garment (LCVG) in the torso area in order to free up the arms and legs by removing the liquid tubes currently used in the ISS EVA suit in the limbs. By using shaped water tubes that greatly increase the contact area with the skin in the torso region of the body, the heat transfer efficiency can be increased to provide the entire liquid cooling requirement and increase mobility by freeing up the arms and legs. Additional potential benefits of this approach include reduced LCVG mass, enhanced evaporation cooling, increased comfort during Mars EVA tasks, and easing of the overly dry condition in the helmet associated with the Advanced Extravehicular Mobility Unit (EMU) ventilation loop currently under development.

  19. Cooling vest for improving surgeons' thermal comfort: a multidisciplinary design project.

    Langø, Thomas; Nesbakken, Ragnhild; Faerevik, Hilde; Holbø, Kristine; Reitan, Jarl; Yavuz, Yunus; Mårvik, Ronald


    A laparoscopic surgeon sometimes experiences heat-related discomfort even though the temperature situation is moderate. The aim of this project was to design a cooling vest using a phase change material to increase thermal comfort for the surgeon. The project focused on the design process to reveal the most important parameters for the design of a cooling vest that could be demonstrated in a clinical setting. We performed an entire design process, from problem analysis, situation observations, concept for a prototype, temperature measurements, and a final design based on clinical testing. The project was conducted by a multidisciplinary team consisting of product designers, engineers, physiologists, and surgeons. We carried out four physiological demonstrations of one surgeon's skin temperatures and heart rate during different laparoscopic procedures. A commercially available cooling vest for firemen and two proof-of-concept prototypes were tested alongside a reference operation without cooling. To aid the final design, one person went through a climate chamber test with two different set-ups of cooling elements. The final design was found to improve the conditions of our test subject. It was found that whole trunk cooling was more effective than only upper trunk cooling. A final design was proposed based on the design process and the findings in the operating room and in the laboratory. Although the experiences using the vest seemed positive, further studies on several operators and more surgical procedures are needed to determine the true benefits for the operator.

  20. Process integration: Cooling water systems design

    Gololo, KV


    Full Text Available This paper presents a technique for grassroot design of cooling water system for wastewater minimization which incorporates the performances of the cooling towers involved. The study focuses mainly on cooling systems consisting of multiple cooling...

  1. Cooling water systems design using process integration

    Gololo, KV


    Full Text Available Cooling water systems are generally designed with a set of heat exchangers arranged in parallel. This arrangement results in higher cooling water flowrate and low cooling water return temperature thus reducing cooling tower efficiency. Previous...




    Through analysis and research of the test data of CFRP fan and GFRP fan in 2 cooling towers in the same chemical factory, compared with the models of international advanced level of glass fiber reinforced plastic fan, air volume flow rate is 13% more. Carbon fiber reinforced fan applied in industrial cooling tower causes the fan performance of a leap, is a world leading level in output, energy saving.%通过对碳纤维风机和玻璃钢风机在某化工厂的实塔对比测试的数据进行整理和分析,碳纤维风机比同型号国际先进水平的玻璃钢风机的风量高13%.碳纤维风机在工业冷却塔中的应用使风机的性能有了飞跃,在出力、节能方面处于世界领先水平.

  3. Solar heating and cooling demonstration project at the Florida solar energy center


    The retrofitted solar heating and cooling system installed at the Florida Solar Energy Center is described. The system was designed to supply approximately 70 percent of the annual cooling and 100 percent of the heating load. The project provides unique high temperature, nonimaging, nontracking, evacuated tube collectors. The design of the system was kept simple and employs five hydronic loops. They are energy collection, chilled water production, space cooling, space heating and energy rejection. Information is provided on the system's acceptance test results operation, controls, hardware and installation, including detailed drawings.

  4. Solar project description: South Bridge Towers no. 6 multi-family cooperative, New York City, New York


    The South Bridge Towers, Inc. solar energy system is a high-rise cooperative apartments subdivision located in New York City, New York. The solar energy collector subsystem is located on the roof of the 27-story tower and consists of 150 flat plate collectors arranged in six arrays. The collectors have a total gross area of 3790 square feed and a net aperture area of 3150 square feet. The collectors are inclined at an angle of 40 deg to horizontal, and oriented to face 14 degrees west of south. Solar energy is stored in a 4000 gallon carbon steel tank located on the tower roof. The system uses a solar energy transport medium of one-half water and one-half propylene glycol in the collector loop. Solar energy, gathered in the collector loop, is transferred to the domestic water storage subsystem by circulating the water through the collector loop heat exchanger and the storage tank.

  5. Practical Arduino Cool Projects for Open Source Hardware

    Oxer, Jonathan


    Create your own Arduino-based designs, gain in-depth knowledge of the architecture of Arduino, and learn the user-friendly Arduino language all in the context of practical projects that you can build yourself at home. Get hands-on experience using a variety of projects and recipes for everything from home automation to test equipment. Arduino has taken off as an incredibly popular building block among ubicomp (ubiquitous computing) enthusiasts, robotics hobbyists, and DIY home automation developers. Authors Jonathan Oxer and Hugh Blemings provide detailed instructions for building a wide range

  6. An experimental system for thermal performance test of large-scale air-cooling towers%大型间接空冷机组空冷塔热力性能实验系统

    席新铭; 郭永红; 杜小泽; 杨立军; 杨勇平


    On the basis of a 600 MW indirect air cooling unit,an experimental system for large-scale air-coo-ing tower was designed by means of the similarity principles,with a proportion of 1 to 30.This system con-sists of modeling air cooling tower,air cooling modeling radiator,heat load power control system and data collection system.During the experiment,the heat load can be regulated by the control system,according to the parameters'value and experimental purpose.The calculation shows the measurement error of heat transfer coefficient of this experimental system is less than 20%.Through this system,the flow and heat transfer characteristics at inside and outside of the dry-cooling tower under various environmental condi-tions can be measured.Moreover,the correlations of flow and heat transfer of air-cooled heat exchanger and the off-design performance of the indirect dry cooling system can be obtained.The hot plume recirculation flows,anti-freezing in winter and the thermo-hydraulic performances for stack and tower integration design can be investigated using this experimental system.The design principle,basic parameters and measuring errors were analyzed.%以某600 MW间接空冷机组的空冷塔为原型,按1∶30的比例,根据相似原理设计了1套自然环境条件下大型间接空冷塔的实验系统。该系统由模型空冷塔、空冷模型散热器、散热热负荷控制系统及数据采集系统等组成。实验期间可根据数值大小及实验目的利用控制系统调整热负荷。对实验数据计算及分析,表明:该空冷塔实验系统的换热系数测量误差小于20%;利用该实验系统,可获得不同环境气象条件下,空冷塔内部空气流场特性,以及散热负荷的空间分布规律;可进行间接空冷系统热空气回流、冬季防冻及烟塔合一条件下塔内气体流动传热机理的研究。

  7. Cooling unit for the AmpaCity project - One year successful operation

    Herzog, Friedhelm; Kutz, Thomas; Stemmle, Mark; Kugel, Torsten


    High temperature super conductors (HTS) can efficiently be cooled with liquid nitrogen down to a temperature of 64 K (-209 °C). Lower temperatures are not practical, because at 63 K (-210 °C) nitrogen becomes solid. To achieve this temperature level the coolant has to be vaporized below atmospheric pressure. Messer has developed a cooling unit with an adequate vacuum subcooler, a liquid nitrogen circulation system, and a storage vessel for cooling an HTS-power cable. Liquid nitrogen is circulated through the superconducting cable to take out the heat, and afterward it is pumped through the subcooler to be recooled. In the circulation system liquid nitrogen is used as a dielectric fluid and as a heat transfer medium. It stays always liquid (subcooled) and does not vaporize. On the secondary side of the subcooler liquid nitrogen from the storage vessel is used as refrigerant. It is vaporized under a pressure of 150 mbar to achieve the desired low temperatures. The cooling unit was delivered in 2013 for the German AmpaCity project of RWE Deutschland AG, Nexans and Karlsruhe Institute of Technology. Within this project RWE and Nexans installed the worldwide longest superconducting power cable in the city of Essen, Germany. The cooling unit cools a 10 kV concentric HTS cable (40 MV A) with a length of 1000 m. The cable is in operation since March 10th, 2014. After more than one year of practical operation many important figures from cable and cooling unit are available. These figures are discussed and a total energy balance is shown to compare liquid nitrogen cooling with alternative mechanical cooling systems.

  8. The WACMOS-ET project – Part 1: Tower-scale evaluation of four remote-sensing-based evapotranspiration algorithms

    Michel, D.


    The WAter Cycle Multi-mission Observation Strategy – EvapoTranspiration (WACMOS-ET) project has compiled a forcing data set covering the period 2005–2007 that aims to maximize the exploitation of European Earth Observations data sets for evapotranspiration (ET) estimation. The data set was used to run four established ET algorithms: the Priestley–Taylor Jet Propulsion Laboratory model (PT-JPL), the Penman–Monteith algorithm from the MODerate resolution Imaging Spectroradiometer (MODIS) evaporation product (PM-MOD), the Surface Energy Balance System (SEBS) and the Global Land Evaporation Amsterdam Model (GLEAM). In addition, in situ meteorological data from 24 FLUXNET towers were used to force the models, with results from both forcing sets compared to tower-based flux observations. Model performance was assessed on several timescales using both sub-daily and daily forcings. The PT-JPL model and GLEAM provide the best performance for both satellite- and tower-based forcing as well as for the considered temporal resolutions. Simulations using the PM-MOD were mostly underestimated, while the SEBS performance was characterized by a systematic overestimation. In general, all four algorithms produce the best results in wet and moderately wet climate regimes. In dry regimes, the correlation and the absolute agreement with the reference tower ET observations were consistently lower. While ET derived with in situ forcing data agrees best with the tower measurements (R2  =  0.67), the agreement of the satellite-based ET estimates is only marginally lower (R2  =  0.58). Results also show similar model performance at daily and sub-daily (3-hourly) resolutions. Overall, our validation experiments against in situ measurements indicate that there is no single best-performing algorithm across all biome and forcing types. An extension of the evaluation to a larger selection of 85 towers (model inputs resampled to a

  9. A cool 'win-win' for Matra

    Wolff, V. [Alstom, Budapest (Hungary)


    In 2004 the Matra plant management initiated a 60 M euro investment programme to increase the generating capacity of units 4 and 5 of the lignite fuelled plant and to give it greater flexibility. This has been achieved by adding a 30 MW natural gas-fired topping gas turbine to each of the 230 MW units, for commissioning by 2007. The power uprate meant the capacity of the dry-tower based cooling system was increased by 24 W for each unit. This has now undergone a major upgrade, involving addition of a wet cooling tower to create a 'hybrid' system. It is one of the largest such projects ever carried out, and the first involving a dry-tower cooling system of the Heller type. The result is increased competitiveness and efficiency, with a 250,000 t reduction in annual carbon dioxide emissions. 3 figs.

  10. Virtual Tower

    Wayne, R.A. [Sandia National Labs., Albuquerque, NM (United States). Security Engineering Dept.


    The primary responsibility of an intrusion detection system (IDS) operator is to monitor the system, assess alarms, and summon and coordinate the response team when a threat is acknowledged. The tools currently provided to the operator are somewhat limited: monitors must be switched, keystrokes must be entered to call up intrusion sensor data, and communication with the response force must be maintained. The Virtual tower is an operator interface assembled from low-cost commercial-off-the-shelf hardware and software; it enables large amounts of data to be displayed in a virtual manner that provides instant recognition for the operator and increases assessment accuracy in alarm annunciator and control systems. This is accomplished by correlating and fusing the data into a 360-degree visual representation that employs color, auxiliary attributes, video, and directional audio to prompt the operator. The Virtual Tower would be a valuable low-cost enhancement to existing systems.

  11. Genotypic variability and persistence of Legionella pulsed-field gel electrophoresis patterns in 16 cooling towers in Shanghai, China%上海市16个冷却塔水中军团菌脉冲场凝胶电泳分型及基因型监测

    陈明亮; 王刚毅; 陈敏; 周海健; 邵祝军; 张曦; 吴凡


    目的 研究上海市公共场所16个空调冷却塔水中军团菌的脉冲场凝胶电泳(PFGE)分型,并连续监测该菌基因型变化.方法 2007年5-10月连续6个月以每月1次的频率采样,从16个公共场所空调冷却塔水中分离军团菌,经血清学凝集试验、胶乳凝集试验分型后,使用PFGE技术对酶切后的军团菌全染色体DNA进行电泳获得指纹图谱,利用BioNumerics软件进行聚类分析.结果 16个冷却塔水中共分离出131株军团菌,包括嗜肺军团菌、博杰曼军团菌、米克戴德军团菌和茴香军团菌,分为52个PFGE型别,其中37个PFGE型别(71.15%)仅分布于1个冷却塔中,即为该冷却塔所特有;15个PFGE型别(28.85%)分布于2个或以上冷却塔中.16个冷却塔具有2个或以上的PFGE型,13个冷却塔(81.25%)中多次出现相同的PFGE型别.2007年6-10月连续5个月从6个冷却塔中分离出18株PFGE型为LPAs.SH0078型的军团菌.结论 冷却塔水中的军团菌基因型具有多样性和复杂性,81.25%的冷却塔水中PFGE型具有持续性,且LPAs.SH0078型广泛分布,可能为优势PFGE型.%Objective To investigate the genotypic characteristics and persistence of Legionella pulsed-field gel electrophoresis (PFGE) patterns in 16 air-conditioner cooling towers in six different public sites of Shanghai. Methods From May to October, continuous sampling was operated once per month in 2007. Legionella strains isolated from the 16 cooling towers were confirmed by serological and latex agglutination. PFGE was applied for the fingerprinting of the isolates, while the culster results of PFGE were analyzed by BioNumerics software. Results 131 strains of Legionella were isolated, including L. pneumophila, L. bozemanae, L. micdadei and L anisa.52 distinguishable PFGE patterns were differentiated among the 16 cooling towers, with 37 patterns were owned by just one cooling tower, which was not shared with other cooling towers, while 15 patterns were shared by more

  12. Seismic analysis of cooling tower under near-fault ground motions%近断层地震动作用下冷却塔地震反应分析

    李辉; 张俊发


    According to characteristics of near-fault ground motions,A 3D finite element model is established for cooling tower in power plant.Multi-strip seismic motion record is selected for inputs.Seismic analysis has been made for cooling tower by time history analysis method.Results has been analyzed under input of velocity pulse records and no velocity pulse records,comparative analysis has been made for results under general seismic action,indicating that this kind of structures are sensitive under the near-fault earthquake motion effect.The influence degree under seismic damage was even larger in near fault area.%针对近断层地震动特征,以火电厂冷却塔为例,建立了三维有限元模型.选取多条近断层地震动记录作为地震动输入,采用时程分析方法对冷却塔进行地震反应分析,分析了含速度脉冲和无速度脉冲地震动输入下的结果,并与一般地震动作用下的结果进行了对比分析.结果表明,该类构筑物对近断层地震动作用较为敏感,近断层处冷却塔的地震破坏影响程度更大.

  13. Comparison between high-efficiency closed hybrid medium re-coolers and open wet cooling towers; Vergelijk tussen hoogrendement gesloten hybride-mediumterugkoelers en open natte-koeltorens

    Huizinga, H.T. [Heat Transfer Holland, Zuidwolde (Netherlands)


    A brief overview is given of the principles in and differences of the cooling systems in the title. [Dutch] Een kort overzicht wordt gegeven van de werking van en de verschillen tussen de in de titel genoemde koelsystemen.

  14. ARRA FEMP Technical Assistance -- Federal Aviation Administration Project 209 -- Control Tower and Support Building, Palm Springs, CA

    Arends, J.; Sandusky, William F.


    This report represents findings of a design review team that evaluated construction documents (at the 100% level) and operating specifications for a new control tower and support building that will be built in Palm Springs, California by the Federal Aviation Administration (FAA). The focus of the review was to identify measures that could be incorporated into the final design and operating specifications that would result in additional energy savings for the FAA that would not have otherwise occurred.

  15. Solar heating and cooling demonstration project at the Florida Solar Energy Center

    Hankins, J.D.


    The retrofitted solar heating and cooling system installed at the Florida Solar Energy Center is described. Information is provided on the system's test, operation, controls, hardware and installation, including detailed drawings. The Center's office building, approximately 5000 square feet of space, with solar air conditioning and heating as a demonstration of the technical feasibility is located just north of Port Canaveral, Florida. The system was designed to supply approximately 70% of the annual cooling and 100% of the heating load. The project provides unique high-temperature, non-imaging, non-tracking, evacuated-tube collectors. The design of the system was kept simple and employs five hydronic loops. They are energy collection, chilled water production, space cooling, space heating and energy rejection.

  16. The inhibition effect of isothiazolone on Legionella in the cooling tower water%异噻唑啉酮对冷却塔水军团菌的抑菌效果

    周伟杰; 吴滂兴; 肖勇; 陈茸; 刘斌


    目的 观察异噻唑啉酮消毒剂对冷却塔水中嗜肺军团菌杀灭效果.方法 选择某公司2个全年连续运行的冷却塔循环水,加入1mg/L异噻唑啉酮活性物质,间隔不同时间采集冷却塔水进行军团茵计数和嗜肺军团茵检测.结果 冷却水消毒间隔时间1、2、3、4和5周以上的嗜肺军团茵阳性率分别为0.00、28.57、40.00、50.00和100.00%.采取的a级行动水平率是28.57%,b级行动水平率4.76%,c和d级行动水平率均为0.00%.结论用1mg/L异噻唑啉酮活性成分消毒冷却水,消毒间隔1周可起到抑军团菌作用,消毒间隔2-5周以上抑军团菌效果下降,需要采取增加杀菌剂添加量.%Objective To observe the effect of isothiazolone disinfectant in killing Legionella pneumophila in cooling tower water. Methods The isothiazolone at concentration of lmg/L was put in the wate of two cooling towers which worked yearly chosen as the for observation the effect on legionella and the samples were sampled at various intervals and detected. Results The positive rates of Legionella pneumophila were 0.00%, 28.57%, 40.00%, 50.00% and 100.00% one, two .three, four and over five weeks after experiment,respectively. The action levels of grade A and B were 28.57% ,and 4.76% , respectively,and the action levels of grade C and D were all 0. Conclusion The active ingredient of isothiazolone at concentration of lmg/L and after acted for a week is eeffective for killing legionella in cooling water. The inhibition effect is not ideal over a period of two to five weeks unless the concentration of isothiazolone is increased and repeated count the quantity of Legionella is indicated until reaching the level of less than 10cfu/L.

  17. Electron cooling

    Meshkov, I.; Sidorin, A.


    The brief review of the most significant and interesting achievements in electron cooling method, which took place during last two years, is presented. The description of the electron cooling facilities-storage rings and traps being in operation or under development-is given. The applications of the electron cooling method are considered. The following modern fields of the method development are discussed: crystalline beam formation, expansion into middle and high energy electron cooling (the Fermilab Recycler Electron Cooler, the BNL cooler-recuperator, cooling with circulating electron beam, the GSI project), electron cooling in traps, antihydrogen generation, electron cooling of positrons (the LEPTA project).

  18. FORIDA Towers - Analysis of UHPFRC Tower

    Jensen, Lars Rom; Dollerup, Niels; Damkilde, Lars

    This report is a detailed analysis of the UHPFRC tower in the hybrid wind turbine tower. The analysis of the UHPFRC tower includes a validation of the Service Limit State (SLS) for both characteristic and frequent load cases, the Ultimate Limit State (ULS) and the Fatigue load state. The analysis...

  19. Arkona measuring tower; Messmast Arkona



    On 18 September 2006, e.on Energy Projects were forced to interrupt the construction of the Arkona measuring tower because of adverse weather conditions. The measuring tower is the first step in the construction of Arkona wind park, which will comprise 80 units of the 5 MW range. The owner is the AWE - Arkona Windpark Entwicklungs GmbH, which is a 98 percent subsidiary of e.on Energy Projects. Work had to be interrupted through November because of bad weather. (orig.)

  20. Microecoenvironment of Legionella pneumophila with its Vitality Overwintering in Air-conditioning Cooling Tower%空调循环水系统军团菌微生态与其存活力研究

    阮素云; 郭常义; 许慧慧; 吴立明


    [Objective]To explore microecoenvironment of Legionella pneutnophila with its vitality overwintering and to provide reference for preventing proliferation and propagation of Legionella pneumophila in air-conditioning cooling tower. [Methods] Two air-conditioning cooling towers with numerous Legionella pneumophila in August were selected to perform spot investigation, meanwhile the environment of cooling tower was imitated to constitute two different ecopatterns of Legionella pneumophila, in which the water and lichen-alga mixture on container surface were periodically and respectively sampled for Legionella pneumophila detection and scanning electron microscope observation. The concentration of total organic carbon (TOC), No3--N and alga in water sample were also tested. [ Results ] In late October, after the air-conditioner was turned off, no Legionella pneumophila was detected in the water sample but as much as 104 CFU/4 cm2 in the lichen-alga mixture, on the biomembrane of which numerous Legionella pneumophila was observed under scanning electron microscope. In the end of December, Legionella pneumophila was not detected in the alga reduction ecopattern but was detected in the cooling tower and the alga addition ecopattern. -In the end of February next year, Legionella pneumophila was not detected in the cooling tower and the alga reduction ecopattern but was detected in alga addition ecopattern. Under scanning electron microscope it was observed that a couple of Legionella pneumophila adhered to the wall of filiform alga in the end of December, but at the end of February next year there was only fungi and its mycelium. [ Conclusion ] It is suggested that the lichen-alga mixture on container surface is the overwintering refuge for Legionella pneumophila which probably gain nutrition from the biomembrane of filiform alga. The fewer algae exist when air-conditioner is turned off and the longer circulating water keeps still, the less the possibility of Legionella

  1. High Temperature Gas-cooled Reactor Projected Markets and Scoping Economics

    Larry Demick


    The NGNP Project has the objective of developing the high temperature gas-cooled reactor (HTGR) technology to supply high temperature process heat to industrial processes as a substitute for burning of fossil fuels, such as natural gas. Applications of the HTGR technology that have been evaluated by the NGNP Project for supply of process heat include supply of electricity, steam and high-temperature gas to a wide range of industrial processes, and production of hydrogen and oxygen for use in petrochemical, refining, coal to liquid fuels, chemical, and fertilizer plants.

  2. 无锡市冷却塔水军团菌污染状况及菌型分析%Contamination and serum type of Legionella in cooling tower water in Wuxi city

    周伟杰; 吴湧兴; 肖勇; 陈茸


    Objective To understand the contamination status and serum type of Legionella in cooling tower water from various places in Wuxi city. Methods Legionella was detected in cooling water from 32 public places and 8 factories in Wuxi from 2004 to 2009. There were total 529 samples. Legionella was tested according to "Central Air Conditioning Ventilation System Hygiene Norms of Public Health Appendix A". Results 75 samples were found Legionella among 529 samples. The total positive rate was 14.18% (75/529). The positive rates were the highest in hospital and market place cooling water, of 27.45% (14/51)and 24.00%(18/75), respectively. In public place the positive rates were highest in July and August, of 18.75% (9/48)and 25.25%(25/99) , respectively. Meanwhile, Legionella was detected in all months in process cooling water in factory. The LP1 was the main type among all the LP, which accounted for 78.67% (59/75). Conclusion Legionella contamination of cooling tower water is serious in various places in Wuxi city. Some measures should be taken to improve the contamination status and prevent the outbreak of Legionnaires' disease.%目的 了解无锡市不同场所冷却塔水中军团菌污染状况和血清型别.方法 按照无锡市地理分布抽取32家公共场所和8家工厂作为监测点,共抽取冷却塔水529份,按照卫生部《集中空调通风系统卫生规范》附录A“空调系统军团菌的检验分析方法”进行检测.结果 529份冷却塔水军团菌的检出率达14.18%(75/529),阳性率以商场和医院为高,分别为27.45%(14/51)和24.00%(18/75).公共场所以7、8月份的阳性率为高,分别为18.75%(9/48)和25.25%(25/99);工厂工艺性冷却塔水军团菌在全年各月份均有检出.军团菌血清型以LP1为主,占78.67%(59/75).结论 无锡市不同场所冷却塔水中存在军团菌污染,对人群健康构成潜在威胁,需引起重视.

  3. Basic factors for efficient cooling ability projects; Grundlaeggande faktorer foer lyckosamma avkylningsprojekt

    Walletun, Haakan [ZW Energiteknik AB, Nykoeping (Sweden); Johnsson, John [Profu AB, Goeteborg (Sweden)


    The aim of the project was to investigate why the question of cooling ability and efficient heat transfer of customer substations do not arouse large interest in the district heating companies. Our main goal in the project group has been to get answered the following question by means of personal interviews and questionnaires: Why do Swedish district heating companies exert relatively low activities concerning cooling ability of substations in spite of the fact that these activities very often have been shown to be very profitable? Totally 13 interviews have been performed and 95 personally addressed questionnaires have been sent out to district heating companies. 52% have responded to the questionnaire, which we consider is an acceptable rate. From the interviews and the answers in the questionnaires, three main problems have emerged: 1. Lack of competence and resources in the individual companies. In this context, this means that problems exist in the company regarding the possibility of managing complex or abstract projects dealing with improvement of efficiency. In some cases, there is just lack of suitable personnel for the project management or for the control of substations. Some time it is just lack of scrutinizing routines for available statistics of district heat consumption and substation operation. 2. Organization of district heating companies. It turned out that projects dealing with the cooling ability concern the whole district heating company. That means that all touched departments should get involved in the project from the very beginning. Because this is not always the case and distinct project goals are sometimes lacking, situations can occur where peoples involved will question the project. 3. Relations to the customers. Both from interviews and the answers of questionnaire one can derive that the discussion of substation operation with the customer is understood as complicated. The reason for that is not - in our opinion - a negative customer

  4. iPhone Cool Projects Ten Great Development Projects for Your iPhone

    Bennett, G


    The iPhone and iPod touch have provided all software developers with a level playing field-developers working alone have the same access to consumers as multinational software publishers. Very cool indeed! To make your application stand out from the crowd, though, it has to have that something extra. You must learn the skills to take your apps from being App Store filler to download chart-topping blockbusters. Developers with years of experience helped write this book. Spend some time understanding their code and why they took the approach they did. You will find the writing, illustrations, co

  5. Impact of urban heat island on cooling and environment: A demonstration project


    Landscaping has been shown in simulation and field studies to reduce building cooling loads by affecting microclimatic factors such as solar radiation, wind speed and air temperature. A demonstration project was undertaken to determine the magnitude of landscape induced changes in microclimate on building cooling loads and water use on four typical residences in Phoenix, Arizona. The energy use and microclimate of three unlandscaped (bare soil, rock mulch) and one landscaped (turf) home were monitored during summer 1990. In the fall, turf was placed around one of the unlandscaped houses, and shade trees planted on the west and south sides of another. Measurements continued during the summer of 1991. Total house air conditioning and selected appliance electrical data were collected, as well as inside and outside air temperatures. Detailed microclimate measurements were obtained for one to two week periods during both summers. Maximum reductions of hourly outside air temperatures of 1 to 1.5{degrees}C, and of daily average air temperatures of up to 1{degrees}C, resulted from the addition of turf landscaping. Addition of small trees to the south and west sides of another treatment did not have a noticeable effect on air temperature. Cooling load reductions of 10% to 17% were observed between years when well-watered turf landscaping was added to a house previously surrounded by bare soil. Addition of small trees to another bare landscape did not produce a detectable change in cooling load. The results of the study are used as input to a standard building energy use simulation model to predict landscape effects on cooling load and water usage for three typical houses, and to develop guidelines for use of energy efficient residential landscapes in Phoenix, Arizona.

  6. 冷却塔风机电机绕组烧毁及控制系统优化%Cooling tower fan motor winding burn and optimization of control system

    宋辉; 陈梅; 姜楠


      Motor winding burn is common fault. Signs before winding burned is not easy to find, and after burned, some direct cause which lead to burn was hidden, analysis difficulty was increased. The motor sealing, winding insulation damage and other aspects were analyzed,At the same time, temperature change of the heat exchanger which did this closed cooling tower system optimization brought for motor timely maintenance and avoiding circulating water temperature.%  绕组烧毁是电机常见故障。绕组烧毁前的迹象不容易发现,而烧毁后一些导致烧毁的直接原因又被掩盖,给事后分析增加了难度。文章就电机密封、绕组绝缘破坏等几方面进行了分析,同时阐述闭式冷却塔系统优化对于电机及时维修和避免循环水温度带来换热器温度变化。

  7. White Tower, London, England

    William the Conqueror; William Rufus; Henry I


    White Tower (Tower of London), London, England. Photograph taken by Terry Barry. There is restoration work being carried out on one of the towers. The White Tower is a central tower at the Tower of London. The great central keep was built by William the Conqueror and finished by his sons and successors, William Rufus and Henry I, around 1087. It is 90 feet high and is of massive construction, the walls varying from 15 feet thickness at the base to almost 11 feet in the upper parts. Above ...

  8. Grohnde. Documentation of the police operation during the demonstration against the NPP Grohnde on 19.03.1977 and the evacuation of the occupied cooling tower site on 23.08.1977; Grohnde. Dokumentation der Polizeieinsaetze anlaesslich der Demonstration gegen das Kernkraftwerk Grohnde am 19.03.1977 und der Raeumung des besetzten Kuehlturmgelaendes am 23.08.1977

    Stricker, Michael


    The documentation of the police operation during the demonstration against the NPP Grohnde on 16.03.1977 and the evacuation of the occupied cooling tower site on 23.08.1977 covers the following issues: involved action forces: police Niedersachsen, police Nordrhein-Westfalen, police Schleswig-Holstein, police Bremen and the Bundesgrenzschutz; concept of the police operation, provisions (lodging and board) for the police, operating resources, details of the operation sequence; post-processing of the operation; the Grohnde trials.

  9. Desinfection of cooling towers and cooling water by UV-treatment on the example of a chemical company; Desinfektion von Kuehltuermen und Kuehlkreislaeufen durch UV-Behandlung am Beispiel eines Chemiebetriebs

    Peuters, J.; Carbone, J. [Sadepan Chimica NV (Belgium); Daele, D. van (DVD Technology); Dams, S.; Weckenmann, J.; Soerensen, M. [a.c.k. aqua concept GmbH, Karlsruhe (Germany)


    Using a Belgian adhesives manufacturer as example, it is shown how formation and growth of micro-organisms can adversely affect a modern manufacturing process. The problem lies not with the actual process solution, but in the cooling section. Installation of a suitably-configured UV reactor allowed long-term operation without any problems from micro-organisms. The outcome was a much more stable process at acceptable cost and with significantly lower volumes of solid waste. (orig.)

  10. Reuso de efluentes em torres de resfriamento - estudo conceitual: Aeroporto Internacional do Rio de Janeiro = Water reuse for cooling towers – conceptual study: Rio de Janeiro International Airport

    Denize Dias de Carvalho


    Full Text Available O reuso de água é ferramenta valiosa na gestão da água, que promove a otimização da utilização do recurso desta, que reduz e, muitas vezes, até elimina os impactos no meio ambiente. Neste trabalho foi investigada a composição do efluente secundário da estação de tratamento de efluentes (ETE APOIO do Aeroporto Internacional do Rio de Janeiro, com o objetivo de propor o processo adequado à reutilização deste efluente como água de reposição nas torres de resfriamento desse Aeroporto. Com base nas análises de cátions, ânions, DBO e DQO, verificou-se o parâmetro SDT - Cl- como crítico para processamento do efluente. Foi proposta uma sequência para reutilização do efluente que continha o tratamento de osmose inversa, o custo do m3 produzido por essa sequência foi estimado em R$ 2,90 m-3. Water reuse is an important tool in water management; it is a conceptthat promotes optimization of the water resource, reducing and often even eliminating environmental impacts. In this work, the composition of a secondary effluent (from the effluent treatment station (ETE APOIO at Rio de Janeiro International Airport was analyzed, with theaim of determining an adequate process for the reutilization of this effluent as replacement cooling water. Chemical analyses such as cation and anion analysis, BOD and COD were performed. Based on these analyses, it was found that TDS - Cl- was the critical parameter foreffluent processing. A treatment system was proposed for effluent reuse including reverse osmosis; the cost estimate per m3 produced by this system was R$ 2.90 m-3.

  11. Final Technical Report on STTR Project DE-FG02-04ER86191 Hydrogen Cryostat for Muon Beam Cooling

    Johnson, Rolland P.


    The project was to develop cryostat designs that could be used for muon beam cooling channels where hydrogen would circulate through refrigerators and the beam-cooling channel to simultaneously refrigerate 1) high-temperature-superconductor (HTS) magnet coils, 2) cold copper RF cavities, and 3) the hydrogen that is heated by the muon beam. In an application where a large amount of hydrogen is naturally present because it is the optimum ionization cooling material, it was reasonable to explore its use with HTS magnets and cold, but not superconducting, RF cavities. In this project we developed computer programs for simulations and analysis and conducted experimental programs to examine the parameters and technological limitations of the materials and designs of Helical Cooling Channel (HCC) components (magnet conductor, RF cavities, absorber windows, heat transport, energy absorber, and refrigerant).The project showed that although a hydrogen cryostat is not the optimum solution for muon ionization cooling channels, the studies of the cooling channel components that define the cryostat requirements led to fundamental advances. In particular, two new lines of promising development were opened up, regarding very high field HTS magnets and the HS concept, that have led to new proposals and funded projects.

  12. Satellite Cloud Data Validation through MAGIC Ground Observation and the S'COOL Project: Scientific Benefits grounded in Citizen Science

    Crecelius, S.; Chambers, L. H.; Lewis, P. M.; Rogerson, T.


    The Students' Cloud Observation On-Line (S'COOL) Project was launched in 1997 as the Formal Education and Public Outreach arm of the Clouds and the Earth's Radiant Energy System (CERES) Mission. ROVER, the Citizen Scientist area of S'COOL, started in 2007 and allows participants to make 'roving' observations from any location as opposed to a fixed, registered classroom. The S'COOL Project aids the CERES Mission in trying to answer the research question: 'What is the Effect of Clouds on the Earth's Climate'. Participants from all 50 states, most U.S. Territories, and 63 countries have reported more than 100,500 observations to the S'COOL Project over the past 16 years. The Project is supported by an intuitive website that provides curriculum support and guidance through the observation steps; 1) Request satellite overpass schedule, 2) Observe clouds, and 3) Report cloud observations. The S'COOL Website also hosts a robust database housing all participants' observations as well as the matching satellite data. While the S'COOL observation parameters are based on the data collected by 5 satellite missions, ground observations provide a unique perspective to data validation. Specifically, low to mid level clouds can be obscured by overcast high-level clouds, or difficult to observe from a satellite's perspective due to surface cover or albedo. In these cases, ground observations play an important role in filling the data gaps and providing a better, global picture of our atmosphere and clouds. S'COOL participants, operating within the boundary layer, have an advantage when observing low-level clouds that affect the area we live in, regional weather patterns, and climate change. S'COOL's long-term data set provides a valuable resource to the scientific community in improving the "poorly characterized and poorly represented [clouds] in climate and weather prediction models'. The MAGIC Team contacted S'COOL in early 2012 about making cloud observations as part of the MAGIC

  13. Preoperational test report, recirculation condenser cooling systems

    Clifton, F.T.


    This represents a preoperational test report for Recirculation Condenser Systems, Project W-030. Project W-030 provides a ventilation upgrade for the four Aging Waste Facility tanks. The four system provide condenser cooling water for vapor space cooling of tanks AY1O1, AY102, AZ1O1, AZ102. Each system consists of a valved piping loop, a pair of redundant recirculation pumps, a closed-loop evaporative cooling tower, and supporting instrumentation; equipment is located outside the farm on concrete slabs. Piping is routed to the each ventilation condenser inside the farm via below-grade concrete trenches. The tests verify correct system operation and correct indications displayed by the central Monitor and Control System.

  14. Preoperational test report, recirculation condenser cooling systems

    Clifton, F.T.


    This represents a preoperational test report for Recirculation Condenser Systems, Project W-030. Project W-030 provides a ventilation upgrade for the four Aging Waste Facility tanks. The four system provide condenser cooling water for vapor space cooling of tanks AY1O1, AY102, AZ1O1, AZ102. Each system consists of a valved piping loop, a pair of redundant recirculation pumps, a closed-loop evaporative cooling tower, and supporting instrumentation; equipment is located outside the farm on concrete slabs. Piping is routed to the each ventilation condenser inside the farm via below-grade concrete trenches. The tests verify correct system operation and correct indications displayed by the central Monitor and Control System.

  15. 蓄能式中央空调冷却水系统横流湿式冷却塔环保降噪的治理方法%The Administrative Methods for the Noise treatment FSR of the many sets of Mechanical Draft crossfolw Cooling Towers in Water Storage Central Air Conditioning System

    冯荣贞; 刘晓东; 周玉琼


    This article takes noise treatment for the many sets of mechanical draft crossflow cooling towers noise for example ,which was layed on the housetop of water storage central air conditioning system. The plans of the noise treatment were given, and the analysis was also brought forward-which including single and united plan.The best plan was selected, the plan was to build the half obturated set of sound insulation and noise elimination, on which there were sound barriers, and to set noise suppressors in cistern of cooling tower. This set was used of light quality structure. Its load was transited by the steel column transmission to the original building column, so that the reinforcement processing measure to the housetop was omitted. Noise treatment measure was few effect of resistance losing for cooling towers, and kept cooling towers thermal performance and normal operation. This paper affords theorical basis for engineering, and a new way was found in decreasing noise of cooling tower.%本文针对蓄冷中央空调系统机力横流湿式冷却塔夜间低谷电满负荷蓄冷运行,白天电力峰值时部分释冷运行的特点及冷却塔自身的噪声污染进行了分析,提出了噪声治理方案,就单个方案及多方案联合进行了综合分析,最终选定了最优实施方案,即“半封闭式声屏导风板降噪+风机消音装置+落水消能降噪器”。半封闭式隔声屏导风板采用轻质结构,屋面增加的荷载通过钢立柱传递至原有建筑物砼立柱上,省去了对原有结构的加固处理措施。并且所采取的降噪措施对冷却塔进排风的阻力损失影响控制在允许范围之内,保证了冷却塔的热工性能及正常运行。本文对工程实际中的冷却塔的降噪提供了新思路。

  16. 广州市公共场所中央空调冷却塔水中军团菌mip基因分型%Mip genotyping of Legionella isolated from central air-conditioning cooling towers in Guangzhou public places

    巩向丽; 张颖; 屈平华; 陈守义


    [Objective] To analyze the genetic characteristics and dominant types of Legionella isolated from central air-conditioning cooling towers in public places in Guangzhou from 2008 to 2010. [Methods] Genomic DNA was extracted from 140 strains of Legionella (119 strains of pneumophila and 21 strains of non-pneumophila). Subsequently, the mip (macrophage in-fectivity potentiator) gene was PCR amplified, purified and sequenced. Those nucleotide sequences were blasted in the European Working Group for Legionella Infections (EWGLI) Database for the mip typing. Phylogenetic trees were constructed with the Neighbor-Joining (NJ) method using MEGA 5.0. [Results] Approximately 700 bp fragments of the mip gene was obtained from 140 Legionella strains. The 119 L. Peumophila were found to be in 10 mip types, with L. Pneumophila-phil-l as the dominant accounting for 52.9% (63/119). The 21 non-L. Pe-numophila from the isolates were found to be in 6 mip types, with L. Feeleii-D3131 as the dominant accounting for 47.6% (10/21). [Conclusion] Great diversity was observed among Legionella strains in central air-conditioning cooling towers of Guangzhou public places, while the mip typing techniques used in this study could be used for fast genotyping of Legionella.%[目的]研究广州市公共场所中央空调冷却塔水中军团菌的基因特征和优势型别.[方法]采用军团菌巨噬细胞感染力增强因子(Macrophage infectivity potentiator,mip)基因分型方法.提取广州市2008-2010年分离的140株(119株嗜肺,21株非嗜肺)军团菌基因组DNA,针对mip基因进行PCR扩增并测序,将核苷酸序列上传至欧洲军团菌感染工作组(EWGLI)数据库进行比对,得到mip型别,并构建系统发育进化树.[结果]140株军团菌均可扩增出700 bp左右的目的条带.119株嗜肺军团菌分为10个mip型别,L.pneumophila-phil-1为优势型别,占52.9% (63/119); 21株非嗜肺军团菌分为6个mip型别,L.feeleii-D3131为优势型别,占47.6% (10

  17. In vitro drug sensitivity analysis of Legionella pneumophila isolated from cooling tower in Shijiazhuang%石家庄市冷却塔水中嗜肺军团菌体外药物敏感性分析

    郭玉梅; 秦丽云; 张慧贤; 王苋; 周吉坤


    Objective To study the drug sensitivity and resistance of Legionella pneumophila isolated from six hospital cooling towers of Shijizhuang. Methods Eight major categories and 26 kinds of antibiotics drug test on 30 strains of Legionella pneumophila isolated from hospital cooling tower by using K-B disk diffusion method. The drug susceptibility testing results were reported refer to the national Health Industry Standard Paper film method (antimicrobial WS/T125 -1999). Results The sensitivity of 30 strains of Legionella pneumophila to Cefuroxime, doxycycline, tetracycline, streptomycin, ciprofloxacin, levofloxacin, moxifloxacin, erythromycin, azithromycin, clarithromycin, rifampicin and ofloxacin was 100%, and they presented different levels of resistance to cefazolin, aztreonam, ampicillin, cephalothin, ceftazidime, tobramycin and cefoxitin. Experimental strains produced eight kinds of resistance spectrum, they were multi-drug resistant strains. Conclusion Resistance is more common to penicillins, cephalosporins, aminoglycosides among 30 starins of Legionella pneumophila. Macrolides, quinolones, rifampicin is superior to the other kinds of antibiotics in vitro susceptibility test, respectively, and these antibiotics can be used as the first choice in clinical therapy of Legionella infections.%目的 了解分离自石家庄市6家医院冷却塔水的嗜肺军团菌的药物敏感性.方法 采用K-B纸片扩散法对30株分离自冷却塔水的嗜肺军团菌进行8大类26种抗生素的药敏实验,参照WS/T125-1999《中华人民共和国卫生行业标准纸片法抗菌药物敏感试验标准》读取结果.结果 30株嗜肺军团菌均对头孢呋辛、强力霉素、四环素、链霉素、环丙沙星、左旋氧氟沙星、莫西沙星、红霉素、阿奇霉素、克拉霉素、利福平、氧氟沙星共12种抗生素敏感,对头孢唑林、氨曲南、氨苄西林、头孢噻吩、头孢他啶、妥布霉素、头孢西丁共7种抗生素均产生

  18. The Leaning Tower



    W hy does the Leaning Tower of Pisa in Italy lean?It leans because of a m istake.It has leanedalm ostsince the day the tower was built.In1173,the people ofPisa,Italy,wanted to build a belltower.They wanted the tower to be them ost beautiful bell tower in all of Italy.The city also needed a bell tower because the church did nothave one.H owever,there was a problem.As soon as the firstfloor ofthe building was finished,the towerstarted to lean.Builders tried to m ake the building straight again as they added m...

  19. Comparative cost study of four wet/dry cooling concepts that use ammonia as the intermediate heat exchange fluid

    Tokarz, R.D.; Braun, D.J.; Johnson, B.M.; Allemann, R.T.; Braun, D.J.; Parry, H.L.; Smith, G.C.; Zaloudek, F.R.


    The projected costs of five alternative wet/dry power plant heat rejection concepts were studied under conditions imposed by hypothetical use in association with the San Juan Unit 3 plant, a fossil-fuel 550-MWe facility currently under construction near the ''Four Corners'' area of New Mexico. Four of the cooling systems use ammonia as a heat transfer medium between the steam condenser and the heat rejection tower, while the fifth uses the condenser cooling water for heat transport. The four alternative concepts were: the HOTERV plate fin with deluge augmented cooling (vertical round towers); the HOTERV plate fin with deluge augmented cooling (horizontal configuration); the separate channel augmented tower (SCAT); a Curtiss-Wright extruded tube with integral fins, augmented with water flowing internally through separate channels, and the augmenting ammonia condenser (AAC); Curtiss-Wright tube augmented with a separate water-cooled condenser close-coupled to a conventional wet tower. The state-of-the-art method was the integrated wet/dry tower currently being constructed at the San Juan Unit 3 station. The comparable capital cost of each of the five concepts was calculated. Fuel savings resulting from using each of the advanced concepts vis-a-vis the reference integrated wet-dry cooling towers, expressed in barrels of oil per year, were calculated. The study indicates that the ammonia system with either the deluge scheme for wet/dry cooling, using the HOTERV plate fin heat exchange, or the Curtiss-Wright chipped-fin surface, (using either the SCAT arrangement or the separate water-cooled ammonia condenser for augmentation) are potentially more cost-effective than the state-of-the-art system for use in a power plant heat rejection system. This has been shown specifically only under conditions imposed by the site at the San Juan plant.

  20. SACTI 模式在核电厂冷却塔环境影响预测的应用研究%The Application of SACTI Model in Environmental Impact Forecast of Cooling Tower in Nuclear Power Plant

    魏国良; 游春华; 王一川; 谭承军; 张琨; 魏新渝


    介绍了SACTI模式的原理和计算程序,以某内陆核电厂为案例预测了冷却塔的环境影响。结果表明:冷却塔可见雾羽、荫屏、太阳能损失、水沉积、盐沉积等环境影响主要分布在厂址主导风向下风向的几百米之内,随距离增加影响逐渐减小,盐沉积量最大值出现在距离300 m处。在冷却塔环境影响评价准则和预测模型改进方面还需开展进一步的研究。%The principle and calculation procedures of SACTI model are described .And the environmental im-pacts from the cooling towers in a nuclear power plant inland are assessed .The results show that visible plume , plume shadowing , solar energy loss , water deposition and salt deposition mainly distribute within a few hundred meters downwind to the study plant site .The adverse environmental effects gradually decrease with the increas-ing of distance , but the maximum value of salt deposit appears at the distance of 300 m.More research is re-quired to determine evaluation criteria and to improve prediction models to better understand the adverse envi -ronmental effects .

  1. Craft-joule project: air-cooled water LiBr absorption cooling machine of low capacity for air conditioning (ACABMA)

    Oliva, A; Castro, J; Perez Segarra, C.D [Universitat Politecnica de Catalunya, Barcelona (Spain); Lucena, M.A [Instituto Nacional de Tecnica Aeroespecial (Spain)] (and others)


    The ACABMA (Air-Cooled water-LiBr Absorption cooling Machine of low capacity for Air- conditioning) 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 basic objective of this project is the development of a new air-cooled absorption cooling machine for air-conditioning, in the low power sector market. Making use of water-LiBr technology together with the air-cooling feature, it is possible to reach a better relationship between quality (in terms of performance, ecology, etc.) and price of such absorption machines, than the ones existing on the market. Air-cooling instead of water cooling saves installation costs specially in small systems and removes the demand for cooling water (an important aspect in Southern-European countries), thus increasing the possible application range. The main interest for the SME proposers is to take advantage of the increasing cooling demand in Europe, specially in southern countries. Another point of interest for the SME proposers is the development of a cheaper cooling and heating system in terms of energy and installation costs. In this moment the solar cooling systems are approx. 30% more expensive than the conventional ones. A cheaper absorption machine due to the air-cooling feature together with the possibility of energy savings due to low generator temperatures, that allow the absorption machine for solar applications or waste heat, will lead to solar cooling and heating systems more competitive to the conventional ones. In order to achieve the above mentioned goal, the following step are necessary and will be carried out in this project: i)solution of the air-cooling of the water-LiBr machine, the main problem that up to now has not allowed commercialization, ii)reduction of the size of the air-cooled elements of the machine in order to reduce the machine costs, iii)development of an efficient control

  2. S/P模式计算的冷却塔烟气抬升高度敏感性试验%Sensitivity test of uplifted height of flue gas from cooling tower based on S/P model

    杨洪斌; 刘玉彻; 汪宏宇; 邹旭东; 张云海


    德国VDI3784的S/P模式为三维流体动力学积分模式,其方程主要描述了无穷小体积元素的质量、动量、静态污染物质量浓度及能量的守恒。利用德国模式进行了冷却塔烟气排放不同参数、不同大气条件下烟气抬升高度的敏感性试验。结果表明:在影响烟气抬升高度的3个气象要素(风速、气温和湿度)中,风速和气温的变化对结果影响较大,而湿度影响较小。在D类稳定度,当环境风速从0.1 m/s增加到15.0 m/s时,抬升高度从711.7 m变为38.5 m。随着环境温度的升高,抬升高度明显单调变小;当稳定度为A类,环境温度从10升到40时,烟气抬升最大高度从688.9 m降低到45.1 m,降低了14倍多。而环境湿度的变化,对抬升高度的影响不是很明显。对于E类稳定度和F类稳定度,当环境湿度从20%增加到70%,最大抬升高度分别从115.3 m和84.6 m降到112.9 m和81.7 m,分别降低了3.43%和2.08%。在影响烟气抬升高度的其他3个因素(凉水塔直径、烟气出口速度和混合气体温度)中,混合气体温度的变化对结果影响较大,而凉水塔直径和烟气出口速度的影响较小。在各类稳定度条件下,当出口温度从20变到90时,烟气抬升高度增加1.2—13.3倍;在各类稳定度条件下,当凉水塔直径从30 m变到90 m,烟气抬升高度仅增加0.63—1.40倍;在各类稳定度条件下,当出口速度从2.5 m/s变到8.0 m/s,烟气抬升高度增加了0.24—0.74倍。%The S/P model from German VDI3784 is a three-dimensional liquid dynamic integral model.Mass and momentum of infinitesimal element,mass concentration of static pollutant and energy balance were described.The sensitivity of uplifted height of flue gas from cooling tower was tested by the S/P model under different parameters and atmospheric conditions.The results indicate that wind speed,air temperature and humidity could influence the uplifted height of flue gas,especially wind speed

  3. Using Roving Cloud Observations from the S'COOL Project to Engage Citizen Scientists

    Lewis, P. M.; Oostra, D.; Moore, S. W.; Rogerson, T. M.; Crecelius, S. A.; Chambers, L. H.


    Students' Clouds Observations On-Line (S'COOL) is a hands-on project, which supports NASA research on the Earth's climate. Through their observations, participants are engaged in identifying cloud-types and levels and sending that information to NASA. The two main groups of S'COOL observers are permanent locations such as regularly participating classrooms, and non-permanent locations or Rovers. These non-permanent locations can be a field trip, vacation, or just an occasional observation from a backyard. S'COOL welcomes participation from any interested observers, especially from places where official weather observations are few and far between. This program is offered to citizen scientists all over the world. They are participating in climate research by reporting cloud types and levels within +/- 15 minutes of a satellite overpass and sending that information back to NASA. When a participant's cloud observation coincides with a satellite overpass, the project sends them an email with a MODIS image of the overpass location, and a comparison of the satellite's cloud data results next to their ground-based report. This allows for the students and citizen scientists to participate in ground-truthing the CERES satellite data, to determine the level of agreement/disagreement. A new tool slated for future use in cloud identification, developed by the S'COOL team, is a mobile application. The application is entitled "Cloud Identification for Students" or "CITRUS". The mobile application utilizes a cloud dichotomous key with images to help with cloud identification. Also included in the application is a link to the project's cloud-reporting page to help with data submission in the field. One of the project's recent and most unique roving observers is a solo ocean rower who has traversed many of the world's ocean basins alone in a rowboat. While rowing across the oceans, she has recently been making cloud observations, which she sends back to us for analysis. In doing so

  4. High Temperature Gas-Cooled Reactor Projected Markets and Preliminary Economics

    Larry Demick


    This paper summarizes the potential market for process heat produced by a high temperature gas-cooled reactor (HTGR), the environmental benefits reduced CO2 emissions will have on these markets, and the typical economics of projects using these applications. It gives examples of HTGR technological applications to industrial processes in the typical co-generation supply of process heat and electricity, the conversion of coal to transportation fuels and chemical process feedstock, and the production of ammonia as a feedstock for the production of ammonia derivatives, including fertilizer. It also demonstrates how uncertainties in capital costs and financial factors affect the economics of HTGR technology by analyzing the use of HTGR technology in the application of HTGR and high temperature steam electrolysis processes to produce hydrogen.

  5. The CERES S'COOL Project: Dynamic NASA Earth Science Education and Public Outreach for Formal and Informal Audiences.

    Crecelius, S.; Chambers, L. H.; Lewis, P. M., Jr.; Harte, T.


    The Clouds and the Earth's Radiant Energy System (CERES) Students' Cloud Observations On-Line (S'COOL) Project began in 1997 as a collaboration between a Virginia Middle School teacher, and several NASA Langley Research Center scientists. The project's aim is to involve classroom students in observing and reporting cloud parameters to assist in the validation of NASA's CERES satellite instruments, thus connecting classroom science work to the outside world. In 2007, S'COOL added a Citizen Science component called ROVER. ROVER is geared toward informal observers not tied to one observation location. The S'COOL Project has been successful due to a combination of its flexibility of implementation, training and involvement opportunities, intuitive and free resources, and this authentic connection to an ongoing scientific activity. Through S'COOL's multiple participation avenues, all participants are invited to collect cloud data following S'COOL guidelines. Their cloud data is later matched with corresponding satellite data. Within a week of submitting their report, a participant will be sent a "match" email, if their observation aligns to a satellite overpass. This "match" shows their ground report next to the satellite data for comparison and analysis. All ground observations and satellite matches are archived in a S'COOL database, accessible to the public. This multi-step process enables an on-going, two-way interaction between students and NASA, which is much more engaging than more typical one-way outreach experiences. To complement and enable the cloud observation component, the S'COOL website offers formal and informal education communities a wide variety of atmospheric science related learning resources. These educator created resources are supplemented with carefully crafted background information from the science team. Alignment of the project to the Next Generation Science Standards is underway now, and will highlight the many science process skills involved

  6. Steam-Electric Power-Plant-Cooling Handbook

    Sonnichsen, J.C.; Carlson, H.A.; Charles, P.D.; Jacobson, L.D.; Tadlock, L.A.


    The Steam-Electric Power Plant Cooling Handbook provides summary data on steam-electric power plant capacity, generation and number of plants for each cooling means, by Electric Regions, Water Resource Regions and National Electric Reliability Council Areas. Water consumption by once-through cooling, cooling ponds and wet evaporative towers is discussed and a methodology for computation of water consumption is provided for a typical steam-electric plant which uses a wet evaporative tower or cooling pond for cooling.

  7. Offshore lattice tower; Gittermast im Meer

    Vries, E. de [Smart Tower, Arnheim (Netherlands)


    The projected offshore wind park has turned out to be a challenge also for non-experts in wind power. A new tower construction was developed in the Netherlands. The contribution points out the advantages of a concrete lattice tower. [German] Die geplante Errichtung von Windparks auf See fordert jetzt auch branchenfremde Ingenieurbueros heraus. In den Niederlanden wurde nun ein voellig neuer Turm entwickelt. Im Beitrag werden die Vorteile der Verwendung eines Betongittermastes aufgezaehlt. (orig.)

  8. Influence of Geometrical Imperfections on Analyses of Door Openings in Tubular Steel Towers for Wind Turbines.

    Tran, Anh Tuan; Veljkovic, Milan, ed. lit.; Rebelo, Carlos; Da Silva, Luís Simões


    Towers for wind turbines are very sensitive to geometrical imperfections. Pattern and amplitude of imperfections significantly influence the strength of the towers. Rather limited number of experiments exists on a tubular tower like structure and no experiments are available considering door opening in towers with cylindrical or polygonal cross-section. One of the objectives of the RFCS research project “HIGH STEEL TUBULAR TOWERS FOR WIND TURBINES, HISTIWIN2” was to investigate current practi...

  9. Experimental study of swirl flow patterns in Gas Conditioning Tower at various entry conditions

    Jinov, Andrei A.; Larsen, Poul Scheel


    In a gas conditioning tower hot flue gas with relatively high dust loads is cooled by injecting water spray near the top. For satisfactory operation wet particles should be kept off walls and all water should have evaporated to yield a uniformly cooled flow before it reaches the bottom of the tower...

  10. A framework for identifying the applicability of heating or cooling technologies based on initial project information

    Cacace, Katie Meng

    In order to fully achieve the energy savings and human comfort benefits of many alternative heating and cooling technologies, design considerations for these technologies must be made during the conceptual design stage. However, at this stage architects are often faced with challenges that inhibit the integration of such technologies. At the early stages of design, architects have limited time and technical knowledge to research alternative technologies and mechanical engineers are typically not yet part of the design team to offer their expertise. To address these problems, this research developed a framework for a Technology Identifier that would inform an architect about alternative heating and cooling technologies that are applicable to their specific project at the conceptual design stage. The framework is based on the premise that a quantitative relationship between the initial project information and a technology's critical output variable(s) for heat transfer to the space can be established. Therefore, to be included in the framework a technology must possess a component that provides direct heat transfer to the space for the framework to determine if the technology can maintain the desired space temperature. The climatic influences on a technology's performance and the effect of changing a technology's input variables on the heat transfer output variable(s) were also quantified. Existing building energy simulation programs were used in these analyses. The framework develops simulation input files for multiple technologies, utilizes existing simulation programs to predict the performance of these technologies, and then displays the output results along with other information that is useful to designers at the conceptual stage. Each simulation input file is compiled from a template that queries databases and requires minimal user input. The output display includes the space temperature, energy consumption, and design considerations of each technology. A

  11. Salt Water Drift From Cooling Towers

    This document may be of assistance in applying the New Source Review (NSR) air permitting regulations including the Prevention of Significant Deterioration (PSD) requirements. This document is part of the NSR Policy and Guidance Database. Some documents in the database are a scanned or retyped version of a paper photocopy of the original. Although we have taken considerable effort to quality assure the documents, some may contain typographical errors. Contact the office that issued the document if you need a copy of the original.

  12. Performance evaluation of an active solar cooling system utilizing low cost plastic collectors and an evaporatively-cooled absorption chiller

    Lof, G. O.; Westhoff, M. A.; Karaki, S.


    During the summer of 1982, air conditioning in Solar House 3 at Colorado State University was provided by an evaporatively-cooled absorption chiller. The single-effect lithium bromide chiller is an experimental three-ton unit from which heat is rejected by direct evaporative cooling of the condenser and absorber walls, thereby eliminating the need for a separate cooling tower. Domestic hot water was also provided by use of a double-walled heat exchanger and 80-gal hot water tank. A schematic of the system is given. Objectives of the project were: (1) evaluation of system performance over the course of one cooling season in Fort Collins, Colorado; (2) optimization of system operation and control; (3) development of a TRNSYS compatible model of the chiller; and (4) determination of cooling system performance in several U.S. climates by use of the model.




    High energy electron cooling [1] is essential to meet the luminosity specification for RHIC II [2]. In preparation for electron cooling, an Energy Recovery Linac (ERL) test facility [3] is under construction at BNL. A preliminary description of Diagnostics for the ERL was presented at an earlier workshop [4]. A significant portion of the eCooling Diagnostics will be a simple extension of those developed for the ERL test facility. In this paper we present a preliminary report on eCooling Diagnostics. We summarize the planned conventional Diagnostics, and follow with more detailed descriptions of Diagnostics specialized to the requirements of high-energy magnetized cooling.


    何国富; 姜颜宁; 杨青; 金微


    以某石油化工工程中的大长径比框架式高塔为对象,采用时程分析法,分析地震作用下设置限位导向支架的框架式高塔的结构响应,并与采用组合结构模型的框架塔进行对比分析。分析表明,设置限位导向支架的框架式高塔,塔体水平位移幅值变化具有时段性增大特征,最大塔顶位移比组合结构模型的框架塔增大约50%;地震作用将导致框架与塔之间产生振荡接触,接触产生的压力以脉冲方式作用到塔体上,并在塔体局部区域产生应力集中和应力幅值极速变化;框架塔的结构模型对塔体底部的应力变化和框架支座反力变化的稳定性影响不大。分析同时认为,设置限位导向支架的框架塔属于多体系结构,采用单一组合结构模型进行工程设计存在一定的安全隐患,建议在目前缺乏设计标准明确规定的条件下,地震作用分析宜采用时程分析法。%Taking a practical high framed-tower with large long-diameter ratio for petro-chemical project as the object, the structure response of high framed-tower with gap limiting support under the seismic effect was analyzed with time-history analysis, whose results were compared with a combined structure model.The analysis indicated that the change in horizontal displacement of the high framed-tower with gap limiting support had the characteristics of increase in time step, max top displacement of tower was 50% greater than that of the high framed-tower of the combined structure model; and the seismic effect would also cause oscillation contact between tower and frame, and the pressure generated by the contact acted on the tower shell in mode of pulse force, which caused stress concentration in local area and a rapid change in stress amplitude.The type of structure model had low influence on stability of the stress variation of tower bottom and reaction variation of frame support.Based on the analysis

  15. High power beam dump project for the accelerator prototype LIPAc: cooling design and analysis

    Parro Albeniz, M.


    In the nuclear fusion field running in parallel to ITER (International Thermonuclear Experimental Reactor) as one of the complementary activities headed towards solving the technological barriers, IFMIF (International Fusion Material Irradiation Facility) project aims to provide an irradiation facility to qualify advanced materials resistant to extreme conditions like the ones expected in future fusion reactors like DEMO (DEMOnstration Power Plant). IFMIF consists of two constant wave deuteron accelerators delivering a 125 mA and 40 MeV beam each that will collide on a lithium target producing an intense neutron fluence (1017 neutrons/s) with a similar spectra to that of fusion neutrons [1], [2]. This neutron flux is employed to irradiate the different material candidates to be employed in the future fusion reactors, and the samples examined after irradiation at the so called post-irradiative facilities. As a first step in such an ambitious project, an engineering validation and engineering design activity phase called IFMIF-EVEDA (Engineering Validation and Engineering Design Activities) is presently going on. One of the activities consists on the construction and operation of an accelerator prototype named LIPAc (Linear IFMIF Prototype Accelerator). It is a high intensity deuteron accelerator identical to the low energy part of the IFMIF accelerators. The LIPAc components, which will be installed in Japan, are delivered by different european countries. The accelerator supplies a 9 MeV constant wave beam of deuterons with a power of 1.125 MW, which after being characterized by different instruments has to be stopped safely. For such task a beam dump to absorb the beam energy and take it to a heat sink is needed. Spain has the compromise of delivering such device and CIEMAT (Centro de Investigaciones Energéticas Medioambientales y Tecnológicas) is responsible for such task. The central piece of the beam dump, where the ion beam is stopped, is a copper cone with

  16. Confusion at the Tower

    Li, Loretta F.


    This study will explore the omission of the Tower of Babel narrative from middle and secondary school world history, world studies, and world geography textbooks and will consider what might be learned from inclusion of the story in the curriculum. A total of 17 textbooks are analyzed. The Tower of Babel narrative is examined within the context of…

  17. 公共场所冷却塔水嗜肺军团菌的基因序列分型研究%Sequence-based typing of Legionella pneumophila isolates from the water of public cooling tower

    章乐怡; 李毅; 郑文力; 马雪莲


    The aim was to investigate the genetic characteristics of Legionellapneumophila (LP) isolated from cooling tower water of the central air conditioning systems in public place of Wenzhou City by the sequence -based typing (SBT) . Seven housekeeping genes including flak , asd, mip, pilE, mompS, proA , and neuA were amplified by PCR from 31 strains of LP, and then the amplified products were sequenced and the results were compared with the database of EWGLI . Furthermore, genotyping results were analyzed by DNAsp 5 .0 , BioNumerics 5 .1, and SplitsTree . Results showed that among 31 LP strains , 11 strains of LP1 were divided into 2 sequence types (STs), and 17 strains of non-LPl were divided into 8 STs , including 7 new STs and one new allele gene. The neuA gene was not amplified from 3 strains , and hence they were not assigned to a specific genotype . The range of 7 housekeeping genes' nucleotide polymorphism (Pi) was 0 .00995 (mip) to 0 .02311 {flaA ) with that flaA has the highest nucleotide polymorphism . The genetic evolutionary relationship of the local isolates was obtained by using cluster analysis . In brief, L . pneumophila strains from the cooling tower water in public place in Wenzhou City are relat -ed to other domestic and foreign strains , and also have region-specific and genetic diversity .%目的 为了解温州市中央空调冷却塔水中嗜肺军团菌(Legionella pneumophila,LP)基因特征,采用序列分型方法(sequenced-based typing,SBT)对公共场所中央空调冷却塔水中的嗜肺军团菌进行分子分型研究.方法选择嗜肺军团菌的7 个管家基因 flaA、asd、mip、pilE、mompS、proA 和 neuA 作为目的 基因,对温州市公共场所中央空调冷却塔水中分离的31株嗜肺军团菌进行PCR扩增并测序.测序结果上传欧盟军团菌感染工作组(EWGLI)数据库进行比对、分型.运用DNAsp 5.0 、Bionumerics5.1及SplitsTree 等软件对分型结果进行分析.结果 31株嗜肺军团菌中,11

  18. Design of an electron cooling device for the accumulator cooler ring in MUSES project

    Tanabé, T; Ohtomo, K; Katayama, T; Yamashita, A; Syresin, E M; Meshkov, I N


    As a part of new experimental facility in the Radio Isotope Beam Factory (RIBF) project at RIKEN, the Multi-Use Experimental Storage rings (MUSES) have an Accumulator Cooler Ring (ACR) which is used for both the accumulation and cooling of RI beams and various experiments. Besides a stochastic cooler, an electron cooler (EC) is presently under development. The ion energy in the ACR ranges from 60 to 400 MeV/u which corresponds to the electron beam (e-beam) energy for the EC from 30 to 250 kV. The maximum current from a 12.7 mm cathode is 4.1 A with a gun perveance of 0.79 mu P. A superconducting solenoid in the gun section generates a magnetic field of 4 T which corresponds to a factor of 20 in adiabatic expansion. The design issues of the gun section, collector, toroidal magnets and compensation solenoids are discussed in detail with some retrospection of the development.

  19. Energy efficiency enhancements for semiconductors, communications, sensors and software achieved in cool silicon cluster project

    Ellinger, Frank; Mikolajick, Thomas; Fettweis, Gerhard; Hentschel, Dieter; Kolodinski, Sabine; Warnecke, Helmut; Reppe, Thomas; Tzschoppe, Christoph; Dohl, Jan; Carta, Corrado; Fritsche, David; Tretter, Gregor; Wiatr, Maciej; Detlef Kronholz, Stefan; Mikalo, Ricardo Pablo; Heinrich, Harald; Paulo, Robert; Wolf, Robert; Hübner, Johannes; Waltsgott, Johannes; Meißner, Klaus; Richter, Robert; Michler, Oliver; Bausinger, Markus; Mehlich, Heiko; Hahmann, Martin; Möller, Henning; Wiemer, Maik; Holland, Hans-Jürgen; Gärtner, Roberto; Schubert, Stefan; Richter, Alexander; Strobel, Axel; Fehske, Albrecht; Cech, Sebastian; Aßmann, Uwe; Pawlak, Andreas; Schröter, Michael; Finger, Wolfgang; Schumann, Stefan; Höppner, Sebastian; Walter, Dennis; Eisenreich, Holger; Schüffny, René


    An overview about the German cluster project Cool Silicon aiming at increasing the energy efficiency for semiconductors, communications, sensors and software is presented. Examples for achievements are: 1000 times reduced gate leakage in transistors using high-fc (HKMG) materials compared to conventional poly-gate (SiON) devices at the same technology node; 700 V transistors integrated in standard 0.35 μm CMOS; solar cell efficiencies above 19% at e-Commerce applications; processors and corresponding data links with 40% and 70% energy savings, respectively, by adaption of clock frequency and supply voltage in less than 20 ns; clock generator chip with tunable frequency from 83-666 MHz and 0.62-1.6 mW dc power; 90 Gb/s on-chip link over 6 mm and efficiency of 174 fJ/mm; dynamic biasing system doubling efficiency in power amplifiers; 60 GHz BiCMOS frontends with dc power to bandwidth ratio of 0.17 mW/MHz; driver assistance systems reducing energy consumption by 10% in cars Contribution to the Topical Issue “International Semiconductor Conference Dresden-Grenoble - ISCDG 2012”, Edited by Gérard Ghibaudo, Francis Balestra and Simon Deleonibus.

  20. Wind tower service lift

    Oliphant, David; Quilter, Jared; Andersen, Todd; Conroy, Thomas


    An apparatus used for maintaining a wind tower structure wherein the wind tower structure may have a plurality of legs and may be configured to support a wind turbine above the ground in a better position to interface with winds. The lift structure may be configured for carrying objects and have a guide system and drive system for mechanically communicating with a primary cable, rail or other first elongate member attached to the wind tower structure. The drive system and guide system may transmit forces that move the lift relative to the cable and thereby relative to the wind tower structure. A control interface may be included for controlling the amount and direction of the power into the guide system and drive system thereby causing the guide system and drive system to move the lift relative to said first elongate member such that said lift moves relative to said wind tower structure.

  1. Verification survey report of the south waste tank farm training/test tower and hazardous waste storage lockers at the West Valley demonstration project, West Valley, New York

    Weaver, Phyllis C.


    A team from ORAU's Independent Environmental Assessment and Verification Program performed verification survey activities on the South Test Tower and four Hazardous Waste Storage Lockers. Scan data collected by ORAU determined that both the alpha and alpha-plus-beta activity was representative of radiological background conditions. The count rate distribution showed no outliers that would be indicative of alpha or alpha-plus-beta count rates in excess of background. It is the opinion of ORAU that independent verification data collected support the site?s conclusions that the South Tower and Lockers sufficiently meet the site criteria for release to recycle and reuse.

  2. Flexible Transpiration Cooled Thermal Protection System for Inflatable Atmospheric Capture and Entry Systems Project

    National Aeronautics and Space Administration — Andrews Space, Inc. proposes an innovative transpiration cooled aerobrake TPS design that is thermally protective, structurally flexible, and lightweight. This...

  3. Advanced Pumps and Cold Plates for Two-Phase Cooling Loops Project

    National Aeronautics and Space Administration — Advanced instruments used for earth science missions require improved cooling systems to remove heat from high power electronic components and maintain tight...

  4. Advanced Pumps and Cold Plates for Two-Phase Cooling Loops Project

    National Aeronautics and Space Administration — Advanced instruments used for earth science missions require improved cooling systems to remove heat from high power electronic components and maintain tight...

  5. Detectors with Improved Near-to-Mid IR Performance and Reduced Cooling Requirements Project

    National Aeronautics and Space Administration — This program will develop an ultra-high performance infrared detector manufacturing technology with improved performance and cost effectiveness, and reduced cooling...

  6. Drop Tower Physics

    Dittrich, William A. Toby


    The drop towers of yesteryear were used to make lead shot for muskets, as described in The Physics Teacher1 in April 2012. However, modern drop towers are essentially elevators designed so that the cable can "break" on demand, creating an environment with microgravity for a short period of time, currently up to nine seconds at the drop tower in Bremen, Germany. Using these drop towers, one can briefly investigate various physical systems operating in this near zero-g environment. The resulting "Drop Tower Physics" is a new and exciting way to challenge students with a physical example that requires solid knowledge of many basic physics principles, and it forces them to practice the scientific method. The question is, "How would a simple toy, like a pendulum, behave when it is suddenly exposed to a zero-g environment?" The student must then postulate a particular behavior, test the hypothesis against physical principles, and if the hypothesis conforms to these chosen physical laws, the student can formulate a final conclusion. At that point having access to a drop tower is very convenient, in that the student can then experimentally test his or her conclusion. The purpose of this discussion is to explain the response of these physical systems ("toys") when the transition is made to a zero-g environment and to provide video demonstrations of this behavior to support in-class discussions of Drop Tower Physics.

  7. Exergy Analysis of a Heat Pump Heating System with a Reversibly Used Cooling Tower%基于冷却塔逆用的热泵制热系统分析

    李毅; 刘小湘


    A mechanical draft cooling tower may be reversibly used, as part of a heat pump system for service hot water, to extract free heat from ambient air. It is advantageous in minimizing the total installation and operating cost. The research focused on the analysis and the evaluation of the exergy performance of the heating system and its components. The second law of thermodynamics performance analysis, also called the exergy performance analysis, can point out the inefficient components of the system with great improvement potential more accurately. And experimental study of a heat pump system is presented, and the analytical formulas of exergy loss, exergy efficiency, exergy loss rate and exergy loss coefficient were derived, respectively. According to the comparison, the most exergy is consumed by the AHU and the compressor, whose exergy destruction ratios are about 14% and 12%, respectively. To achieve better whole system's exergy performance, the recommend improvements should focus on these two kind of components. Furthermore, the results can draw an engineer's attention towards the components where the most availability is being destroyed and quantify the extent to which modification of one component affects, favorably or unfavorably, the performance of other components of the system.%冷却塔逆用已经在热泵制热系统中得到实际应用并取得了一定的节能效果。本文从热力学第二定律的角度,对冷却塔逆用作为低温热源的热泵制热系统进行了火用分析。构建了系统各部件火用分析数学模型,并结合实验系统现场测试数据进行分析,分析过程中采用火用损失、火用效率、火用损失率、火用损失系数评价指标综合评价。结果表明在系统制热工况下,末端空气处理机组与压缩机火用损失、火肭员失率明显高于整个系统中其他设备及部件,火用损失率分别为14%和12%,是整个系统改进的主要对象。该研究有

  8. Optimal Inflatable Space Towers with 3 - 100 km Height

    Bolonkin, Alexander


    Theory and computations are provided for building inflatable space towers up to one hundred kilometers in height. These towers can be used for tourism, scientific observation of space, observation of the Earth's surface, weather and upper atmosphere, and for radio, television, and communication transmissions. These towers can also be used to launch space ships and Earth satellites. These projects are not expensive and do not require rockets. They require thin strong films composed from artificial fibers and fabricated by current industry. The towers can be built using present technology. The towers can be used (for tourism, communication, etc.) during the construction process and provide self-financing for further construction. The tower design does not require work at high altitudes; all construction can be done at the Earth's surface. The transport system for a tower consists of a small engine (used only for friction compensation) located at the Earth's surface. The tower is separated into sections and has special protection mechanisms in case of damage. Problems involving security, control, repair, and stability of the proposed towers are addressed in other publications. The author is prepared to discuss these and other problems with serious organizations desiring to research and develop these projects.

  9. Ejection Tower Lab

    Federal Laboratory Consortium — The Ejection Tower Facility's mission is to test and evaluate new ejection seat technology being researched and developed for future defense forces. The captive and...

  10. Development of an Anti-Vibration Controller for Magnetic Bearing Cooling Systems Project

    National Aeronautics and Space Administration — This proposal outlines a program to develop a vibration-free reverse-Brayton cycle cooling system using specially-tuned magnetic bearings. Such a system is critical...

  11. Sensitivity-Based Simulation Software for Optimization of Turbine Blade Cooling Strategies Project

    National Aeronautics and Space Administration — In recent years, there has been a tendency to use ever-higher gas turbine inlet temperatures, resulting in ever-higher heat loads necessitating efficient cooling....

  12. A Reusable, Oxidizer-Cooled, Hybrid Aerospike Rocket Motor for Flight Test Project

    National Aeronautics and Space Administration — The proposed innovation is to use the refrigerant capabilities of nitrous oxide (N2O) to provide the cooling required for reusable operation of an aerospike nozzle...

  13. CTE-Matched, Liquid-Cooled, High Thermal Conductivity Heat Sink Project

    National Aeronautics and Space Administration — We propose the development of a CTE-matched, liquid-cooled, high thermal conductivity heat sink for use in spacecraft thermal management applications. The material...

  14. A Liquid Hydrogen Cooler with a Cooling Capacity of 20 Watts Project

    National Aeronautics and Space Administration — For the future spaceport and long-term storage of liquid hydrogen NASA requires cryocoolers that can provide cooling power in the range of 20 watts at 20 K. The...

  15. Low-Cost and Light-Weight Transpiration-Cooled Thrust Chambers Project

    National Aeronautics and Space Administration — The proposed effort aims to evaluate the feasibility of using transpiration-cooled Titanium as the primary material in small-scale thrust chambers for in-space...

  16. Actively Cooled Silicon Lightweight Mirrors for Far Infrared and Submillimeter Optical Systems Project

    National Aeronautics and Space Administration — Schafer proposes to demonstrate 2 different methods for actively cooling our 5-7.5 kg/m2 areal density Silicon Lightweight Mirrors (SLMS?) technology for future NASA...

  17. Demonstration of a Passive Thermal Management System for Cooling Electronics in Extreme Environments Project

    National Aeronautics and Space Administration — Extended operation of exploratory systems on the surface of planets like Venus, means that techniques to cool system electronics to essentially room temperature...

  18. Recycler Electron Cooling Project: Mechanical vibrations in the Pelletron and their effect on the beam

    Kazakevich, Grigory M.; Burov, A.; Boffo, C.; Joireman, P.; Saewert, G.; Schmidt, C.W.; Shemyakin, A.; /Fermilab


    The Fermilab's Recycler ring will employ an electron cooler to cool stored 8.9 GeV antiprotons [1]. The cooler is based on an electrostatic accelerator, Pelletron [2], working in an energy-recovery regime. A full-scale prototype of the cooler has been assembled and commissioned in a separate building [3]. The main goal of the experiments with the prototype was to demonstrate stable operation with a 3.5 MeV, 0.5 A DC electron beam while preserving a high beam quality in the cooling section. The quality is characterized, first of all, by a spread of electron velocities in the cooling section, which may be significantly affected by mechanical vibration of the Pelletron elements. This paper describes the results of vibration measurements in the Pelletron terminal and correlates them with the beam motion in the cooling section.

  19. Thermoacoustic Duplex Technology for Cooling and Powering a Venus Lander Project

    National Aeronautics and Space Administration — Sierra Lobo proposes to develop a technology that can provide both cooling and electric power generation using heat. When coupled with a radioisotope heat source,...

  20. History of stochastic beam cooling and its application in many different projects

    Caspers, F


    This paper gives an overview of the evolution of stochastic beam cooling from the very beginning (in 1968) until the present-day (2011). The early history, the main achievements and the growing number of the worldwide applications are outlined.

  1. Low-Cost Manufacturing Technique for Advanced Regenerative Cooling for In-Space Cryogenic Engines Project

    National Aeronautics and Space Administration — The goal of the proposed effort is to use selective laser melting (SLM, an additive manufacturing technique) to manufacture a hot fire-capable, water-cooled spool...

  2. Design and Fabrication of a Breadboard, Fully Conductively Cooled, 2-Micron, Pulsed Laser for the 3-D Winds Decadal Survey Mission Project

    National Aeronautics and Space Administration — Design and fabricate a space-qualifiable, fully conductively cooled, 2-micron pulsed laser breadboard meeting the projected 3-D Winds mission requirements. Utilize...

  3. Projected Benefits of New Residential Evaporative Cooling Systems: Progress Report #2

    Kutscher, C.; Eastment, M.; Hancock, E.; Reeves, P.


    The use of conventional evaporative cooling has rapidly declined in the United States despite the fact that it has high potential for energy savings in dry climates. Evaporative systems are very competitive in terms of first cost and provide significant reductions in operating energy use, as well as peak-load reduction benefits. Significant market barriers still remain and can be addressed through improved systems integration. This report investigates the first of these approaches, exploring innovative components. The U.S. Department of Energy (DOE) Building America research teams are investigating the use of two promising new pieces of residential cooling equipment that employ evaporative cooling as a part of their system design. The OASys unit, which is a combination of direct and indirect evaporative cooling stages developed by Davis Energy Group (DEG) and manufactured by Speakman CRS, is used to ultimately provide outside air to the living space. The outdoor air provided is indirectly and directly evaporatively cooled in two stages to a condition that can be below the wet-bulb (wb) temperature of the outside air, thus outperforming a conventional single-stage direct evaporative cooler.

  4. The Effect Analysis of Strain Rate on Power Transmission Tower-Line System under Seismic Excitation

    Li Tian; Wenming Wang; Hui Qian


    The effect analysis of strain rate on power transmission tower-line system under seismic excitation is studied in this paper. A three-dimensional finite element model of a transmission tower-line system is created based on a real project. Using theoretical analysis and numerical simulation, incremental dynamic analysis of the power transmission tower-line system is conducted to investigate the effect of strain rate on the nonlinear responses of the transmission tower and line. The results sho...

  5. Cellular Phone Towers, Towers, Published in 2008, Duchesne County.

    NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, was produced all or in part from Other information as of 2008. It is described as 'Towers'. Data by this publisher are often...

  6. YouTube Video Project: A "Cool" Way to Learn Communication Ethics

    Lehman, Carol M.; DuFrene, Debbie D.; Lehman, Mark W.


    The millennial generation embraces new technologies as a natural way of accessing and exchanging information, staying connected, and having fun. YouTube, a video-sharing site that allows users to upload, view, and share video clips, is among the latest "cool" technologies for enjoying quick laughs, employing a wide variety of corporate activities,…

  7. American Recovery and Reinvestment Act (ARRA) - FEMP Technical Assistance - Federal Aviation Administration - Project 209 - Control Tower and Support Building, Boise, Idaho

    Arends, J.; Sandusky, William F.


    This report documents an energy audit performed by Pacific Northwest National Laboratory (PNNL) and Redhorse Corporation (Redhorse) conducted on the Federal Aviation Administration (FAA) control tower and base building in Boise, Idaho. This report presents findings of the energy audit team that evaluated construction documents and operating specifications (at the 100% level) followed by a site visit of the facility under construction. The focus of the review was to identify measures that could be incorporated into the final design and operating specifications that would result in additional energy savings for FAA that would not have otherwise occurred.

  8. Drop Tower Facility at Queensland University of Technology

    Plagens, Owen; Castillo, Martin; Steinberg, Theodore; Ong, Teng-Cheong

    The Queensland University of Technology (QUT) Drop Tower Facility is a {raise.17exscriptstyle˜}2.1 second, 21.3 m fall, dual capsule drop tower system. The dual capsule comprises of an uncoupled exterior hollow drag shield that experiences drag by the ambient atmosphere with the experimental capsule falling within the drag shield. The dual capsule system is lifted to the top of the drop tower via a mechanical crane and the dropping process is initiated by the cutting of a wire coupling the experimental package and suspending the drag shield. The internal experimental capsule reaches the bottom of the drag shield floor just prior to the deceleration stage at the air bag and during this time experience gravity levels of {raise.17exscriptstyle˜}10textsuperscript{-6} g. The deceleration system utilizes an inflatable airbag where experimental packages can be designed to experience a maximum deceleration of {raise.17exscriptstyle˜}10textsuperscript{18} g for {raise.17exscriptstyle˜}0.1 seconds. The drag shield can house experimental packages with a maximum diameter of 0.8 m and height of 0.9 m. The drag shield can also be used in foam mode, where the walls are lined with foam and small experiments can be dropped completely untethered. This mode is generally used for the study of microsatellite manipulation. Payloads can be powered by on-board power systems with power delivered to the experiment until free fall occurs. Experimental data that can be collected includes but is not limited to video, temperature, pressure, voltage/current from the power supply, and triggering mechanisms outputs which are simultaneously collected via data logging systems and high speed video recording systems. Academic and commercial projects are currently under investigation at the QUT Drop Tower Facility and collaboration is openly welcome at this facility. Current research includes the study of heterogeneously burning metals in oxygen which is aimed at fire safety applications and

  9. The TALE Tower Detector

    Bergman, D. R.

    The TA Low Energy Extension will include a Tower FluorescenceDetector. Extensive air showers at the lowest usful energies for fluorescence detectors will in general be close to the detector. This requires viewing all elevation angles to be able to reconstruct showers. The TALE Tower Detector, operating in conjunction with other TALE detectors will view elevation angles up to above 70 degrees, with an azimuthal coverage of about 90 degrees. Results from a prototype mirror operated in conjunction with the HiRes detector will also be presented.

  10. Developing Young Researchers: 15 Years of Authentic Science Experiences for K-12 with NASA's S'COOL Project

    Chambers, L. H.; Crecelius, S.; Rogerson, T.; Lewis, P. M.; Moore, S.; Madigan, J. J.; Deller, C.; Taylor, J.


    In late 1996, members of the Atmospheric Science Directorate at NASA's Langley Research Center decided that there had to be a better way to share the excitement of our research than black and white, text-heavy Fact Sheets. We invited a group of local teachers to a half-day session on Center to help guide an improved approach. We suggested a variety of approaches to them, and asked for feedback. They were eager for anything other than black and white Fact Sheets! Fortunately, one local middle school science teacher took us up on the offer to stick around and talk over lunch. In that conversation, she said that anything that would connect the science her kids studied in the classroom to the outside world - especially to NASA! - would be very motivating to her students. From that conversation was born the Students' Cloud Observations On-Line (S'COOL Project), now a nearly 16-year experiment in K-12 science, technology, engineering, and math (STEM) engagement. S'COOL is the Education and Public Outreach (EPO) arm of the Clouds and the Earth's Radiant Energy System (CERES) project, and involves K-12 students as a source of ground truth for satellite cloud retrievals. It was designed from the beginning as a 2-way project, with communication of information from the students to NASA, but also from NASA back to the students. With technology evolution since the project began, we have continued to enhance this focus on 2-way interaction. S'COOL involves students with observation skills, math skills (to compute cloud cover from multiple observers or convert units), geography skills (locating their school on a map and comparing to satellite imagery), and exposes them to cutting edge engineering in the form of a series of NASA satellites. As a priority Earth Observing Instrument, CERES currently flies on Terra, Aqua and NPP, with an additional instrument in development for JPSS. Students are involved in occasional Intensive Observing Periods (as with the launch of NPP), and are

  11. Risk Evaluation and Warning of Legionella Contamination in Aerosols and Cooling Towers in Centralized Air Conditioning System in Public Places%公共场所中央空调系统冷却塔水及气溶胶军团菌污染的风险评估和预警研究

    陈健; 赵志荣; 施明美; 彭志行; 董坤; 张大伟; 刘洋; 赵锴; 陈道利


    Objective To develop risk evaluation index system and warning model of Legionella contamination in aerosols and cooling towers in centralized air conditioning systems in public places. Methods During May -Sep.2008 and 2009, 70 water samples and 110 aerosol samples were collected from cooling towers for isolated culture and PCR of Legionella. The relationships between Legionella detection from cooling waters and from aerosols were analyzed. Eighteen variables of affecting Legionella contamination of cooling waters and aerosols were screened, the cumulative odds models were constructed by ordinal logistic regression. Results Integrated risk evaluation index system of Legionella contamination was constructed based on the results of isolated culture and PCR of Legionella for water samples from cooling towers and PCR of Legionella for aerosol samples from cooling towers. According to the three indexes mentioned above, Legionella contamination risk levels were divided into four ranks,such as none, low, moderate and high risk level. The risk warning model had been constructed, which included 4 variables, such as water temperature of cooling tower, residual chlorine, pH value and relative humidity of aerosols sampling points. Conclusion The model has formed scientific evaluation of Legionella contamination risk in cooling waters and aerosols, completes quick field monitoring with sensitive and simple measure indexes, decides risk levels of Legionella contamination of cooling waters and aerosols. The sensitivity and specificity of the model prediction attains to the demand of risk precaution.%目的 构建中央空调系统冷却塔水及气溶胶军团菌污染的风险评估指标体系和风险预警模型.方法 于2008、2009年的5-9月采集马鞍山市16户宾馆、商场、公共浴室冷却塔水样70份,冷却塔气溶胶样品110份,分别进行军团菌分离培养和嗜肺军团菌mip基因的PCR检测.分析冷却塔水军团菌检出与气溶胶军团菌检

  12. 广州市荔湾区集中空调系统冷却水塔铜绿假单胞菌污染状况%Pseudomonas Aeruginosa Contamination in Cooling Tower of Central Air Conditioning System in Liwan District of Guangzhou City

    方强; 谭志熹


    [Objective]To learn the contamination statues of Pseudomonas aeruginosa in cooling tower of central air conditioning system, provide scientific basis for the prevention and control of Pseudomonas aeruginosa.[Methods]From April to September 2010, 28 water samples were collected from the cooling towers of central air conditioning system in public places of Liwan district, and the indexes of pH value, Legionella pneumophila and Pseudomonas aeruginosa were tested.The Sanitation criterion of centralized air ventilation system in public places (2006) was adopted to test the Legionella pneumophila, the Methods for examination of drinking natural mineral water ( GB8538 - 2008 ) was applied to test the Pseudomonas aeruginosa, and the Standard examination methods for chinking water ( GB/T5750 - 2006) was adopted to test the pH value.[Results]Among 28 samples, the total positive rate of Pseudomonas aeruginosa was57.14%, that of Legionella pneumophila was 60.71%, and the difference was not significant ( P > 0.05 ).There was negative correlation between the positive rate of Pseudomonas aeruginosa and the PH value.[Conclusion]Pseudomonas aeruginosa contamination is serious in cooling tower of central air conditioning system, and it is necessary to strengthen the cleaning and disinfection of cooling towers.%目的 了解集中空调冷却水塔铜绿假单胞菌污染状况,为铜绿假单胞菌的防控工作提供科学依据.方法 2010年4-9月,对荔湾区公共场所28个集中空调冷却水塔水样的pH值、嗜肺军团菌、铜绿假单胞菌等微生物指标进行检测,嗜肺军团菌按照卫生部(2006)检测,铜绿假单胞菌分析按照GB 8538-2008饮用天然矿泉水检验方法进行,pH值按照(GB/T 5750-2006)中检验方法进行.结果 检测的28份冷却水塔中的水样品,铜绿假单胞菌总阳性检出率为57.14%,嗜肺军团菌阳性检出率为60.71%,两者比较,差异无统计学意义(P>0.05),铜绿假单胞菌的阳性检出率和p

  13. Cooler than air. Evaporative cooling makes it possible; Kuehler als die Luft erlaubt.. Verdunstungskuehlung macht's moeglich

    Sturies, Hubert [EVAPCO Europe GmbH, Meerbusch (Germany)


    The contribution outlines the variants of evaporation cooling aggregates that are commercially available. It should be mentioned that cooling towers of 200 kW to 20 MW can be constructed in serial production. Over 20 MW, modular cooling towers comprised of cooling cells are used that can be assembled on site. (orig.)

  14. TacTowers

    Ludvigsen, Martin; Fogtmann, Maiken Hillerup; Grønbæk, Kaj


    The interactive training equipment, TacTower, is aimed at supporting multiple elite athletes, such as handball players in training their micro-tactical skills in close-contact situations. It focuses on psychomotor abilities and trains the skills involved in reading the opponents’ actions...

  15. Final Technical Report on STTR Project DE-FG02-06ER86282 Development and Demonstration of 6-Dimensional Muon Beam Cooling

    Muons, Inc.


    The overarching purpose of this project was to prepare a proposal for an experiment to demonstrate 6-dimensional muon beam cooling. The technical objectives were all steps in preparing the proposal, which was successfully presented to the Fermilab Accelerator Advisory Committee in February 2009. All primary goals of this project have been met.

  16. Singular Strategic Project on bio climatic architecture and solar cooling (PSE-ARFRISOL); Proyecto Singular Estrategico sobre arquitectura bioclimatica y frio solar (PSE-ARFRISOL)

    Heras Celemin, M. R.


    The R and D activities for the scientific-technological singular strategic Project on Bio climatic Architecture and Solar Cooling PSE-ARFRISOL are being carried out from November 2005 to December 2010. This project aims to demonstrate that bio climatic architecture and low-temperature solar energy are the appropriate basic elements for climatization of future buildings. (Author) 12 refs.

  17. 电视塔桅钢结构工程的监理质量安全控制信息读析%Supervision of Quality and Safety Control of TV Tower Masted Steel Projects



    With the expansion of communication supervision business scope, simply mastering the knowledge of communication tower is not enough; it is also necessary to learn about the professional knowledge of television transmitting tower. This paper aims to discuss how to deal with television tower business. First, be clear about the situation. There are many risks and uncertainty in foreign business operation environment. Domestically, the economic structure strategic adjustment is ongoing. How to adapt to the rapidly developing society and unpredictable market under the economic developing mode transferring environment is the key to the company. In order to keep the market share, the company must intensify efforts to expand market and solicit new business, thinking carefully, seizing opportunities and improving its ability. Second, improve service quality. Customer service goal is the starting point and objective of the company's service, and the effect of customer service goal is reflected in the optimization of service knowledge, service experience and service management and customer's satisfaction. Third, due to the specialty of broadcasting and TV industry and the difference between television tower construction and communication tower, this kind of project occupy a small proportion of the construction projects in the same period, so there is specialty and challenge for the existing communications supervision industry.%  根据通信监理业务范围的不断扩大,不光要对通信铁塔知识的掌握,而且对广电行业的电视发射塔的专业知识也要逐步进行了解,如何应对广电的电视塔业务是本文的主要研讨目的。首先、认清形式:国外业务运营环境风险大,存在着不确定性;国内在推进经济结构战略性调整,加快转变经济发展方式的导向下,公司如何适应社会快速发展和市场变化莫测的严峻形势。为了保持公司市场占有率,加大力度持续拓展市

  18. Good Towers of Function Fields

    Bassa, Alp; Beelen, Peter; Nguyen, Nhut


    In this paper, we will give an overview of known and new techniques on how one can obtain explicit equations for candidates of good towers of function fields. The techniques are founded in modular theory (both the classical modular theory and the Drinfeld modular theory). In the classical modular...... setup, optimal towers can be obtained, while in the Drinfeld modular setup, good towers over any non-prime field may be found. We illustrate the theory with several examples, thus explaining some known towers as well as giving new examples of good explicitly defined towers of function fields....

  19. Current and Projected Capabilities of the Solar Tower Atmospheric Cherenkov Effect Experiment (STACEE) for gamma -ray Astronomy below 100 GeV

    Chantell, M. C.; Covault, C. E.; Dragovan, M.; Ong, R. A.; Oser, S.; Bhattacharya, D.; Tumer, O. T.; Gregorich, D. T.; Hanna, D. S.; Williams, D. A.


    There are currently no experiments, either satellite or ground-based, that are sensitive to astrophysical gamma -rays in the energy range between 20 and 250 GeV. We are developing the Solar Tower Atmospheric Cherenkov Effect Experiment (STACEE) to explore this energy range. STACEE will use heliostat mirrors at the National Solar Thermal Test Facility, located at Sandia National Laboratorys near Albuquerque NM., to collect Cherenkov light produced by extensive air showers initiated by high energy gamma -rays. The STACEE collaboration has recently completed a series of tests at this site that demonstrate the ability of this experiment to operate with a gamma -ray energy threshold well below 100 GeV. We present the results of these tests and use them to predict the scientific potential of a 32 heliostat experiment operating for a full winter-spring observing season.

  20. Linux toys II 9 Cool New Projects for Home, Office, and Entertainment

    Negus, Christopher


    Builds on the success of the original Linux Toys (0-7645-2508-5) and adds projects using different Linux distributionsAll-new toys in this edition include a car computer system with built-in entertainment and navigation features, bootable movies, a home surveillance monitor, a LEGO Mindstorms robot, and a weather mapping stationIntroduces small business opportunities with an Internet radio station and Internet caf ̌projectsCompanion Web site features specialized hardware drivers, software interfaces, music and game software, project descriptions, and discussion forumsIncludes a CD-ROM with scr

  1. Cool snacks

    Grunert, Klaus G; Brock, Steen; Brunsø, Karen


    such a product requires an interdisciplinary effort where researchers with backgrounds in psychology, anthropology, media science, philosophy, sensory science and food science join forces. We present the COOL SNACKS project, where such a blend of competences was used first to obtain thorough insight into young...

  2. TacTowers

    Ludvigsen, Martin; Fogtmann, Maiken Hillerup; Grønbæk, Kaj


    The interactive training equipment, TacTower, is aimed at supporting multiple elite athletes, such as handball players in training their micro-tactical skills in close-contact situations. It focuses on psychomotor abilities and trains the skills involved in reading the opponents’ actions and anti...... for the elite athletic community, as this domain holds interesting challenges while also inspiring relevant, new forms of interaction design for other domains....

  3. Motivating and Constructing Understanding through Observation and Data Analysis: The S`COOL and MY NASA DATA Projects

    Chambers, L. H.; Rogerson, T. M.; Diones, D. D.; Moore, S. W.; Oots, P. C.; Phelps, C. S.


    Inquiry is widely recognized as an effective method for science teaching. Exploration of the local environment lends itself well to this method. However, to foster understanding about the broader global scale of the Earth system, another approach is needed. Here we present two projects that seek to provide motivation and resources for helping K-12 students construct their own understanding of our Earth system. The S`COOL Project, begun in 1997, seeks to motivate students across the entire K-12 spectrum (with a particular focus on upper elementary grades) to learn relevant science basics and how these basics tie in to a larger picture. The project uses a connection to an on-going NASA science investigation, the Clouds and the Earth`s Radiant Energy System (CERES) project, as a powerful motivator. Student cloud observations coordinated with the passage of orbiting satellite instruments provide useful validation information for the CERES science team. The students receive timely feedback, with a simple and direct link to the corresponding piece of satellite data. Finally, students are encouraged to perform data analysis through an on-line database and the provision of simple tools that allow students to look at not only their own familiar observations, but also those from other participants around the world. The project is placed in the context of our efforts to understand the Earth's energy balance, which controls our climate. The MY NASA DATA project, begun in 2004, provides K-12 students (with a particular focus on middle and high school) with direct on-line access to Earth system science data for global inquiry. The project collects over 140 Earth system science parameters from NASA and other government resources through a single, relatively simple, web-based visualization interface. In addition to offering a large number of contributed lesson plans and science projects on specific topics, this website enables students to explore their own inquiry questions to

  4. Cooling and crystallization of rhyolite-obsidian lava: Insights from micron-scale projections on plagioclase microlites

    Sano, Kyohei; Toramaru, Atsushi


    To reveal the cooling process of a rhyolite-obsidian flow, we studied the morphology of plagioclase microlites in the Tokachi-Ishizawa lava of Shirataki, northern Hokkaido, Japan, where the structure of the lava can be observed from obsidian at the base of the flow to the innermost rhyolite. Needle-like micron-scale textures, known as ;projections;, occur on the short side surfaces of the plagioclase microlites. Using FE-SEM we discovered a positive correlation between the lengths and spacings of these projections. On the basis of the instability theory of an interface between melt and crystal, and to understand the length and spacing data, we developed a model that explains the positive correlation and allows us to simultaneously estimate growth rates and growth times. Applying the model to our morphological data and the estimated growth rates and growth times, we suggest that the characteristics of the projections reflect the degree of undercooling, which in turn correlates with lava structure (the obsidian at the margin of the flow experienced a higher degree of undercooling than the interior rhyolite). The newly developed method provides insights into the degree of undercooling during the final stages of crystallization of a rhyolitic lava flow.

  5. Distributed power from solar tower systems : a MIUS approach

    Romero, M.; Marcos, M.J.; Tellez, F.M.; Blanco, M. [CIEMAT/DER-PSA, Madrid (Spain); Fernandez, V. [AICIA, Escuela Superior de Ingenieros, Seville (Spain); Baonza, F. [Escuela Politecnica Superior, Madrid (Spain). Dpto. Ingenieria Mecanica; Berger, S. [Ecole Nat. des Ponts et Chaussees, Marne-la-Vallee (France)


    One of the short-term priorities for renewable energies in Europe is their integration into communities and energy islands for local power supply (blocks of buildings, new neighborhoods in residential areas, shopping centers, hospitals, recreational areas, ecoparks, small rural areas or isolated ones such as islands or mountain communities). Following this strategy, the integration of small solar tower fields into so-called MIUS (Modular Integrated Utility Systems) is proposed. This application strongly influences field concepts leading to modular multi-tower systems able to more closely track demand, meet reliability requirements with fewer megawatts of installed power and spread construction costs over time after output has begun. In addition, integration into single-cycle high-efficiency gas turbines plus waste-heat applications clearly increments the solar share. The main questions are whether solar towers can be redesigned for such distributed markets and how to make them feasible. This paper includes the design and performance analysis of a 1.36 MW plant and its integration in the MIUS system, as well as the expected cost of electricity and a sensitivity analysis of the small tower plant's performance with design parameters like heliostat configuration and tower height. A practical application is analyzed for a shopping center with a solar tower producing electricity and waste heat for hot water and heating and cooling of spaces. (Author)

  6. Optimization of Overall Project of ChinaLEad-Alloy Cooled Reactor

    DUAN; Tian-ying; LONG; Bin; HU; Yun; LIU; Xing-ming; SUN; Gang; LIU; Yi-zhe; YANG; Yong; PEI; Zhi-yong; FENG; Wei-wei; YU; Xiao


    <正>The application of accelerator driven sub-critical reactor which is able to transmute spent fuel and long-lived radioactive fission products is highly concerned in the international research projects. Lots of researches have been done in many countries. While China Institute of Atomic Energy has built a fast

  7. Projective rectification of infrared images from air-cooled condenser temperature measurement by using projection profile features and cross-ratio invariability.

    Xu, Lijun; Chen, Lulu; Li, Xiaolu; He, Tao


    In this paper, we propose a projective rectification method for infrared images obtained from the measurement of temperature distribution on an air-cooled condenser (ACC) surface by using projection profile features and cross-ratio invariability. In the research, the infrared (IR) images acquired by the four IR cameras utilized are distorted to different degrees. To rectify the distorted IR images, the sizes of the acquired images are first enlarged by means of bicubic interpolation. Then, uniformly distributed control points are extracted in the enlarged images by constructing quadrangles with detected vertical lines and detected or constructed horizontal lines. The corresponding control points in the anticipated undistorted IR images are extracted by using projection profile features and cross-ratio invariability. Finally, a third-order polynomial rectification model is established and the coefficients of the model are computed with the mapping relationship between the control points in the distorted and anticipated undistorted images. Experimental results obtained from an industrial ACC unit show that the proposed method performs much better than any previous method we have adopted. Furthermore, all rectified images are stitched together to obtain a complete image of the whole ACC surface with a much higher spatial resolution than that obtained by using a single camera, which is not only useful but also necessary for more accurate and comprehensive analysis of ACC performance and more reliable optimization of ACC operations.

  8. 石家庄市集中空调冷却塔水中嗜肺军团菌的基因序列分型研究%Sequence-based typing research for Legionella pneumophila isolated from the air-conditioning cooling towers in Shijiazhuang

    郭玉梅; 周吉坤; 剧慧栋; 秦丽云; 王苋; 徐保红; 吕国平


    Objective To evaluate the gene characteristics of Legionella pneumophila isolated from the water samples of air—conditioning cooling towers in public places of Shijiazhuang, Hebei by sequence—based typing (SBT). Methods Genomic DNA was extracted from 35 strains of Lpl from the water samples of cooling towers in Shijiazhuang. Seven kinds of housekeeping genes including flaA , pilE, asd, mip, mompS, proA , neuA of Legionella pneumophila were amplified by PCR. Amplified products were purified and sequenced and the results were compared with the database of EWGLI,and the genotype (sequence type, ST) was get, typing and analyzing of the phylogenetic were conducted. Results A total of 35 strains of serotype Lpl Legionella pneumophila were divided into four ST types,one was not typed due to absence of neuA gene, one was new ST type, and was newly assigned (ST1021) by EWGLI, the remaining was 32 strains of ST1 , one strain of ST345. MEGA4.0 software was used to establish the phylogenetic tree. Conclusion The dominant ST type is ST1, while ST345 and ST1021 are unique type of Legionella pneumophila isolated from the water samples of air-conditioning cooling tower in Shijiazhuang. SBT typing can be used as one of the important means to study Legionella pneumophila evolutionary relationships.%目的 采用基因序列分型方法(sequence-basedtyping,SBT)研究石家庄市集中空调冷却塔水中军团菌基因特征.方法 将石家庄市集中空调冷却塔水中分离出的35株Lp1血清型嗜肺军团菌提取基因组DNA,选取嗜肺军团菌7个管家基因flaA、pilE、asd、mip、mompS、p roA、neuA进行PCR扩增,将扩增产物纯化后测序.测序结果上传欧盟军团菌感染工作组( EWGLI)数据库进行比对,得到基因型别(sequence type,ST),对结果进行基因序列分型和系统进化分析.结果 35株Lp1血清型嗜肺军团菌共分为4个ST型,其中1株由于neuA基因不能被扩增而未分型;1株为

  9. SACTI模型在核电厂大型自然通风冷却塔对局地环境影响预测评价中的应用%Application of SACTI Model in Environmental Impact Prediction and Assessment of NPP's Large Scale Natural Draft Cooling Tower

    王炫; 杜风雷


    The environmental impacts caused by the large scale natural draft cooling tower such as shadowing,solar energy loss,water deposition and salt deposition has become a popular subject of research in China.As there is no large scale natural draft cooling tower in nuclear power plant built in China yet,model prediction thusly becomes a common method to solve this problem.This paper presents basic principles and structure of SACTI model,from which the simulation results derived of China Pengze NPP and US Amos Power Plant is compared then demonstrating its practical application and main factors affecting the results.Conclusions show that simulation results of SACTI model have a great potential when lack input of monitoring data,this research work will provide reference to future research.%大型自然通风冷却塔造成的荫屏、太阳辐射损失、水沉积和盐沉积等环境影响已逐渐成为当前国内研究的热点.由于国内目前尚未有已建成的核电厂大型自然通风冷却塔,所以利用预测模型研究大型自然通风冷却塔的环境影响成为当前的一个关注点.首先介绍了美国Argonne国家实验室开发的冷却塔评价模型SACTI的基本原理和结构组成,以江西彭泽核电厂为例,与美国Amos电厂的预测结果进行比较分析,说明了SACTI模型在实际工作中的应用及影响其计算结果的主要因素.结果表明,在缺乏监测数据的情况下,SACTI模型的模拟结果具有重要的参考意义,同时本文的研究成果为深入开展该项研究工作提供了有意义的基础.

  10. A cooling system for buildings using wind energy

    Daiyan, H. [Islamic Azad Univ., Semnan Branch (Iran)


    In Iranian historical architecture wind towers are used for cooling and ventilation. A wind tower is a tall structure that stands on the building. A wind tower is used in dray land, and only uses wind energy for conditioning. Its technology dates back over 1000 years. Wind towers were designed according to several parameters, some of the most important of which were building type, cooling space volume, wind direction and velocity and ambient temperature. This paper studies wind towers and characterizes airflow route and explains how to decrease temperature. To confirm the quality of the wind tower, some experiments in a case study shows it can decrease room temperature on comfort range and room temperature is almost constant on during day. (au)

  11. The European JASMIN Project for the Development of a New Safety Simulation Code, ASTEC-Na, for Na-cooled Fast Neutron Reactors

    GIRAULT N.; VAN DORSSELAERE J.p.; Jacq, F.; BRILLANT G.; KISSANE Martin; BANDINI, G; Buck,M.; CHAMPIGNY J.; Hering, W; Perez-Martin, S.; Herranz, L; RAISON Philippe; Reinke, N; TUCEK Kamil; VERWAERDE D.


    The 4-year JASMIN collaborative project, involving 9 organizations, was launched by IRSN end of 2011 within the 7th European R&D Framework Programme on the enhancement of Na-cooled Fast Neutron Reactors (SFR) safety for a higher resistance to severe accidents. The project aims at developing a new European simulation code, ASTEC-Na, with a modern architecture, sufficiently flexible to account for innovative reactor designs and eventually new types of fuel and claddings and accounting for resul...

  12. Final Technical Report on STTR Project DE-FG02-02ER86145 Pressurized RF Cavities for Muon Ionization Cooling

    Rolland Johnson


    This project was to design and build an RF test cell (TC), which could be operated at 800 MHz, filled with high pressure gases including hydrogen, at temperatures down to that of liquid nitrogen, in strong magnetic fields, in a strong radiation environment, and with interchangeable electrodes, in order to examine the use of high-pressure RF cavities for muon beam cooling.




    The Florida Footprint experiments were a series of field programs in which perfluorocarbon tracers were released in different configurations centered on a flux tower to generate a data set that can be used to test transport and dispersion models. These models are used to determine the sources of the CO{sub 2} that cause the fluxes measured at eddy covariance towers. Experiments were conducted in a managed slash pine forest, 10 km northeast of Gainesville, Florida, in 2002, 2004, and 2006 and in atmospheric conditions that ranged from well mixed, to very stable, including the transition period between convective conditions at midday to stable conditions after sun set. There were a total of 15 experiments. The characteristics of the PFTs, details of sampling and analysis methods, quality control measures, and analytical statistics including confidence limits are presented. Details of the field programs including tracer release rates, tracer source configurations, and configuration of the samplers are discussed. The result of this experiment is a high quality, well documented tracer and meteorological data set that can be used to improve and validate canopy dispersion models.

  14. The Mercury Project: A High Average Power, Gas-Cooled Laser For Inertial Fusion Energy Development

    Bayramian, A; Armstrong, P; Ault, E; Beach, R; Bibeau, C; Caird, J; Campbell, R; Chai, B; Dawson, J; Ebbers, C; Erlandson, A; Fei, Y; Freitas, B; Kent, R; Liao, Z; Ladran, T; Menapace, J; Molander, B; Payne, S; Peterson, N; Randles, M; Schaffers, K; Sutton, S; Tassano, J; Telford, S; Utterback, E


    Hundred-joule, kilowatt-class lasers based on diode-pumped solid-state technologies, are being developed worldwide for laser-plasma interactions and as prototypes for fusion energy drivers. The goal of the Mercury Laser Project is to develop key technologies within an architectural framework that demonstrates basic building blocks for scaling to larger multi-kilojoule systems for inertial fusion energy (IFE) applications. Mercury has requirements that include: scalability to IFE beamlines, 10 Hz repetition rate, high efficiency, and 10{sup 9} shot reliability. The Mercury laser has operated continuously for several hours at 55 J and 10 Hz with fourteen 4 x 6 cm{sup 2} ytterbium doped strontium fluoroapatite (Yb:S-FAP) amplifier slabs pumped by eight 100 kW diode arrays. The 1047 nm fundamental wavelength was converted to 523 nm at 160 W average power with 73% conversion efficiency using yttrium calcium oxy-borate (YCOB).

  15. NKS-R ExCoolSe mid-term report KTH severe accidents research relevant to the NKS-ExCoolSe project[KTH = Royal Institute of Technology, Sweden

    Hyun Sun Park; Truc-Nam Dinh [Royal Inst. of Technology (Sweden)


    The present mid-term progress report is prepared on the recent results from the KTH severe accident research program relevant to the objective of the ExCoolSe project sponsored by the NKS-R program. The previous PRE-MELT-DEL project at KTH sponsored by NKS provided an extensive assessment on the remaining issues of severe accidents in general and suggested the key issues to be resolved such as coolability and steam explosion energetics in ex-vessel which became a backbone of the ExCoolSe project in NKS. The EXCOOLSE project has been integrated with, and leveraged on, parallel research program at KTH on severe accident phenomena the MSWI project which is funded by the APRI program, SKI in Sweden and HSK in Switzerland and produced more understanding of the key remaining issues. During last year, the critical assessment of the existing knowledge and current SAMG and designs of Nordic BWRs identified the research focus and initiated the new series of research activities toward the resolution of the key remaining issues specifically pertaining to the Nordic BWRs.(au)

  16. The Numerical Analysis of Transmission Tower-Line System Wind-Induced Collapsed Performance

    Zhuoqun Zhang; Hongnan Li; Gang Li; Wenming Wang; Li Tian


    The numerical simulation of transmission tower-line systems' progressive collapse performance is considered as a major research hotspot and significant project, due to the increasing number of wind-induced collapse accidents recently. In this study, the finite element models for single tower and transmission tower-line system were established to simulate wind-induced progressive collapse by birth-to-death element technique in ABAQUS/Explicit. The wind field, based on the Kaimal fluctuating wi...

  17. Operational cost minimization in cooling water systems

    Castro M.M.


    Full Text Available In this work, an optimization model that considers thermal and hydraulic interactions is developed for a cooling water system. It is a closed loop consisting of a cooling tower unit, circulation pump, blower and heat exchanger-pipe network. Aside from process disturbances, climatic fluctuations are considered. Model constraints include relations concerning tower performance, air flowrate requirement, make-up flowrate, circulating pump performance, heat load in each cooler, pressure drop constraints and climatic conditions. The objective function is operating cost minimization. Optimization variables are air flowrate, forced water withdrawal upstream the tower, and valve adjustment in each branch. It is found that the most significant operating cost is related to electricity. However, for cooled water temperatures lower than a specific target, there must be a forced withdrawal of circulating water and further makeup to enhance the cooling tower capacity. Additionally, the system is optimized along the months. The results corroborate the fact that the most important variable on cooling tower performance is not the air temperature itself, but its humidity.

  18. New developments on preparation of cooled and bunched Radioactive Ion beams at ISOL facilities the ISCOOL project and the rotating wall cooling

    Podadera-Aliseda, I


    The future of physics research with radioactive isotopes is linked to the development of more accurate and specific experiments which will work with more exotic and energetic nuclei. Requirements from experiments are getting more and more stringent and represent a big challenge for the preparation of ion beams, since each one demands different optical specifications to optimize its setup and improve its results. This thesis focuses on the new developments achieved in preparation of RIB's (Radioactive Ion Beams) at ISOL facilities. Optical beam improvements based on cooling and bunching are the main points of the work. The design of a new general purpose second generation RFQCB (Radio Frequency ion Quadrupole Cooler and Buncher) for ISOLDE, the oldest ISOL facility, will be completely described. Nowadays, RFQCB's are one of the most important devices in the beam preparation stage thanks to the capacity to cool and bunch low-intensity ion beams quickly, easily and with great efficiency. The thesis will detail t...

  19. 对北京地区利用冷却塔进行冬季空调制冷的分析%Analysis of Winter Air-Conditioning Refrigeration Using Cooling Tower in Beijing Area



    冷却塔制冷在国外叫做FREE COOLING,直译过来就是免费制冷,因取消了冷水机组的运转,节省了能量,从而达到节能的效果.北京地区大型的商场、办公楼、计算机中心等都有内区需要在冬季进行空调制冷,也有不少采用冷却塔进行冬季空调制冷的方式,现将笔者做冷却塔冬季制冷设计的一些经验做一总结.

  20. Recovery Act: Federspiel Controls (now Vigilent) and State of California Department of General Services Data Center Energy Efficient Cooling Control Demonstration. Final technical project report

    Federspiel, Clifford; Evers, Myah


    Eight State of California data centers were equipped with an intelligent energy management system to evaluate the effectiveness, energy savings, dollar savings and benefits that arise when powerful artificial intelligence-based technology measures, monitors and actively controls cooling operations. Control software, wireless sensors and mesh networks were used at all sites. Most sites used variable frequency drives as well. The system dynamically adjusts temperature and airflow on the fly by analyzing real-time demands, thermal behavior and historical data collected on site. Taking into account the chaotic interrelationships of hundreds to thousands of variables in a data center, the system optimizes the temperature distribution across a facility while also intelligently balancing loads, outputs, and airflow. The overall project will provide a reduction in energy consumption of more than 2.3 million kWh each year, which translates to $240,000 saved and a reduction of 1.58 million pounds of carbon emissions. Across all sites, the cooling energy consumption was reduced by 41%. The average reduction in energy savings across all the sites that use VFDs is higher at 58%. Before this case study, all eight data centers ran the cooling fans at 100% capacity all of the time. Because of the new technology, cooling fans run at the optimum fan speed maintaining stable air equilibrium while also expending the least amount of electricity. With lower fan speeds, the life of the capital investment made on cooling equipment improves, and the cooling capacity of the data center increases. This case study depicts a rare technological feat: The same process and technology worked cost effectively in eight very different environments. The results show that savings were achieved in centers with diverse specifications for the sizes, ages and types of cooling equipment. The percentage of cooling energy reduction ranged from 19% to 78% while keeping temperatures substantially within the

  1. SENER molten salt tower technology. Ouarzazate NOOR III case

    Relloso, Sergio; Gutiérrez, Yolanda


    NOOR III 150 MWe project is the evolution of Gemasolar (19.9 MWe) to large scale Molten Salt Tower plants. With more than 5 years of operational experience, Gemasolar lessons learned have been the starting point for the optimization of this technology, considered the leader of potential cost reduction in CSP. In addition, prototypes of plant key components (heliostat and receiver) were manufactured and thoroughly tested before project launch in order to prove the new engineering solutions adopted. The SENER proprietary technology of NOOR III will be applied in the next Molten Salt Tower plants that will follow in other countries, such as South Africa, Chile and Australia.

  2. Design of Fire Auto-alarm and Control System of the Container Tower for the Second-phase Project of Shanghai Waigaoqiao Port Area%上海外高桥港区二期工程集装箱调度中心火灾报警系统设计介绍



    简要介绍上海外高桥港区二期工程集装箱调度中心火灾报警系统的设计及体会。%It briefly introduces design and understandings of the fire auto-alarm and control system of the Container Tower for the 2nd-phase Project of Shanghai Waigaoqiao Port Area.

  3. Seismic Performance Research of Transmission Tower in Consideration of the Pile-soil-structure System

    Liu, Chuncheng; Mao, Long; Wang, Chongyang; Zha, Chuanming


    The seismic performance of transmission tower in consideration of pile-soil- structure dynamic interaction is researched through numerical simulation. Based on a transmission tower of a specific project, pile-soil-transmission tower coupled system is established. By using the method of time history, the pile-soil- transmission tower system dynamic response under seismic load were calculated, and comparing with the results without considering interaction system. Results show that, after considering interaction of the system, the period of the structure have extended and the mode of the structure lagged. On soft sites, compare with no considering the interaction, the results have a big difference, the relative increment of the maximum displacement at the top of the tower is 39.82%, respectively. Therefore it is suggested that the pile-soil-structure dynamic interaction should be fully considered in aseismic design of transmission tower on soft sites and medium soft sites.

  4. Monitoring peak power and cooling energy savings of shade trees and white surfaces in the Sacramento Municipal Utility District (SMUD) service area: Project design and preliminary results

    Akbari, H.; Bretz, S.; Hanford, J.; Rosenfeld, A.; Sailor, D.; Taha, H. [Lawrence Berkeley Lab., CA (United States); Bos, W. [Sacramento Municipal Utility District, CA (United States)


    Urban areas in warm climates create summer heat islands of daily average intensity of 3--5{degrees}C, adding to discomfort and increasing air-conditioning loads. Two important factors contributing to urban heat islands are reductions in albedo (lower overall city reflectance) and loss of vegetation (less evapotranspiration). Reducing summer heat islands by planting vegetation (shade trees) and increasing surface albedos, saves cooling energy, allows down-sizing of air conditioners, lowers air-conditioning peak demand, and reduces the emission of CO{sub 2} and other pollutants from electric power plants. The focus of this multi-year project, jointly sponsored by SMUD and the California Institute for Energy Efficiency (CIEE), was to measure the direct cooling effects of trees and white surfaces (mainly roofs) in a few buildings in Sacramento. The first-year project was to design the experiment and obtain base case data. We also obtained limited post retrofit data for some sites. This report provides an overview of the project activities during the first year at six sites. The measurement period for some of the sites was limited to September and October, which are transitional cooling months in Sacramento and hence the interpretation of results only apply to this period. In one house, recoating the dark roof with a high-albedo coating rendered air conditioning unnecessary for the month of September (possible savings of up to 10 kWh per day and 2 kW of non-coincidental peak power). Savings of 50% relative to an identical base case bungalow were achieved when a school bungalow`s roof and southeast wall were coated with a high-albedo coating during the same period. Our measured data for the vegetation sites do not indicate conclusive results because shade trees were small and the cooling period was almost over. We need to collect more data over a longer cooling season in order to demonstrate savings conclusively.

  5. Allegheny County Cell Tower Points

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset portrays cell tower locations as points in Allegheny County. The dataset is based on outbuilding codes in the Property Assessment Parcel Database used...

  6. Allegheny County Cell Tower Points

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset portrays cell tower locations as points in Allegheny County. The dataset is based on outbuilding codes in the Property Assessment Parcel Database used...


    Federal Laboratory Consortium — The Drop Tower is used to simulate and measure the impact shocks that are exerted on parachute loads when they hit the ground. It is also used for HSL static lift to...


    Valderi D. Leite


    Full Text Available About 245 thousand tones of municipal solid w aste are collected daily in Brazil. Nearly 32 thousand tones of the collected amount are treated in sanitary landfill, which generates biogas and leachate as byproduct. The leachate resulting from sanitary landfill contains high concentration of carbonaceous and nitrogenized material. The crucial question is that the biodegradation of the carbonaceous material is difficult as long as the nitrogenized material is presen t in the form of ammoniacal nitrogen (NH 4 + , which compromises performance of biological tr eatment process. Therefore, a physical and chemical treatment of the leachate should be done before its biological treatment, especially for reduction of ammoniacal nitr ogen concentration and for propitiating the realization of application of biological treatment. The treatment of leachate requires specific consideration, which is not needed fo r other types of waste. In the specific case in this study, where ammoniacal nitrogen concentration was about 2,200 mgN L -1 and the BOD 5 /COD ratio was 0.3, the study of ammonia stripping process was performed. Ammonia stripping process was studied in pack ed towers of 35 L capacity each and the parameters investigated were pH, ratio of contact area/leach volume and the aeration time. One of the parameters that influenced most in efficiency of ammonia stripping process was pH of the leachate since it contributes in conversion of ammoniacal nitrogen from NH 4 + to NH 3 .

  9. Tower Temperature and Humidity Sensors (TWR) Handbook

    Cook, DR


    Three tall towers are installed at the Atmospheric Radiation Measurement (ARM) Climate Research Facility: a 60-meter triangular tower at the Southern Great Plains (SGP) Central Facility (CF), a 21-meter walkup scaffolding tower at the SGP Okmulgee forest site (E21), and a 40-meter triangular tower at the North Slope of Alaska (NSA) Barrow site. The towers are used for meteorological, radiological, and other measurements.

  10. Performance analysis and improvement of the use of wind tower in hot dry climate

    Bouchahm, Yasmina; Bourbia, Fatiha [Universite Mentouri, Departement d' Architecture, Laboratoire d' architecture bioclimatique et d' environnement, Constantine (Algeria); Belhamri, Azeddine [Universite Mentouri, Departement de Genie Climatique, Constantine (Algeria)


    Wind towers for passive evaporative cooling offer real opportunity for improving the ambient comfort conditions in building whilst reducing the energy consumption of air-conditioning systems. This study aims at assessing the thermal performance of a bioclimatic housing using wind towers realized in a hot dry region of Algeria. Performance monitoring and site measurement of the system provide data which assist model validation. The analysis and site measurement are encouraging, and they confirm the advantage of the application of this passive cooling strategies in hot dry climate. A mathematical model is developed using heat and mass transfer balances. For a more effective evaporative cooling, a number of improvements on wind tower configurations are proposed. (author)

  11. User's manual for the BNW-I optimization code for dry-cooled power plants. Volume III. [PLCIRI

    Braun, D.J.; Daniel, D.J.; De Mier, W.V.; Faletti, D.W.; Wiles, L.E.


    This appendix to User's Manual for the BNW-1 Optimization Code for Dry-Cooled Power Plants provides a listing of the BNW-I optimization code for determining, for a particular size power plant, the optimum dry cooling tower design using a plastic tube cooling surface and circular tower arrangement of the tube bundles. (LCL)

  12. Survey of Legionella pneumophila in cooling tower water of central air conditioning system in guangxi in 2009-2012%广西2009~2012年集中式中央空调冷却塔水嗜肺军团菌调查

    廖和壮; 林玫; 权怡; 周凌云


    目的 了解广西公共场所集中式中央空调冷却塔水嗜肺军团菌污染状况,为科学防制提供依据.方法 采集2009~2012年广西14个地级市公共场所301份集中式中央空调冷却塔水进行嗜肺军团菌培养及鉴定.结果 共检出嗜肺军团菌95株,阳性率31.56%(95/301),LP1型占54.74% (52/95),LP2-15型占45.26%(43/95).中央空调系统使用单位(酒店、宾馆、超市和医院)该菌阳性率40.29% (83/206).45株嗜肺军团菌1型经脉冲场凝胶电泳(PFGE)分型,获得了41种基因型别,带型比较分散,未发现绝对优势带型.结论 广西公共场所水体嗜肺军团菌污染普遍存在且较严重,对人群健康构成潜在威胁,需要引起重视,以防军团菌病的暴发流行.%Objective To understand the prevalence of Legionella pneumophila in cooling tower water in public places of Guangxi,.Methods A total of 301 samples of cooling tower water were collected from the central air-conditioning system in 14 prefectures of Guangxi during 2009 and 2012.Bacterial culture and identification for Legionella pneumophila was carried out on the samples collected.Results A total of 95 strains of Legionella pneumophlla (LP) were isolated with a positive rate of 31.56%(95 / 301).LP1 accounted for 54.74% (52/95)and LP2-15 for 45.26%(43/95).The prevalence of this organism was 40.29% (83/206)in facilities using central air-conditioning system,including restaurants,hotels,supermarkets and hospitals.A total of 41 genotypes were identified in the 45 strains of LP1 assayed by pulsed field gel electrophoresis (PFGE),suggesting that diverse genotypes has been found and no predominant genotype has been detected.Conclusions The high prevalence of legionella bacteria in water in public places is a potential threat to the health of the population.Attention should be drawn on the contamination of legionella to avoid outbreak caused by this organism.

  13. Integration of Small Solar tower Systems into Distributed Power Islands

    Romero, M.; Marcos, M. J.; Tellez, F. M.; Blanco, M.; Fernandez, V.; Baonza, F.; Berger, S. [Ciemat, Madrid (Spain)


    One of the short-term priorities for renewable energies in Europe is their integration for local power supply into communities and energy islands (blocks of buildings, new neighborhoods in residential areas, shopping centers, hospitals, recreational areas, eco-paks, small rural areas or isolated ones such as islands or mountain communities). Following this strategy, the integration of small tower fields into so-called MIUS (Modular Integrated Utility Systems) is proposed. This application strongly influences field concepts leadings to modular multi-tower systems able to more closely track demand, meet reliability requirements with fewer megawatts of installed power and spread construction costs over time after output has begum. In addition, integration into single-cycle high-efficiency gas turbines plus waste-heat applications clearly increments the solar share. The chief questions are whether solar towers can be redesigned for such distributed markets and the keys to their feasibility. This paper includes the design and performance analysis of a 1.36-MW plant and integration in the MIUS system, as well as the expected cost of electricity and a sensitivity analysis of the small tower plant's performance with design parameters like heliostat configuration and tower height. A practical application is analyzed for a shopping center with 85% power demand during day-time by using a hybrid solar tower and a gas turbine producing electricity and waste heat for hot water and heating and cooling of spaces. The operation mode proposed is covering night demand with power from the grid and solar-gas power island mode during 14 hours daytime with a maximum power production of 1.36 MW. (Author) 26 refs.

  14. Guided design of heating and cooling mains for lower water and energy consumption and increased efficiency

    Gololo, V


    Full Text Available in higher cooling water flowrate and low cooling water return temperature thus reducing cooling towers efficiency. This indicates the importance of the system structure, the possibility of mixing of heating or cooling water; recycling and reuse of heating...

  15. Liquid Cooled Garments


    Astronauts working on the surface of the moon had to wear liquid-cooled garments under their space suits as protection from lunar temperatures which sometimes reach 250 degrees Fahrenheit. In community service projects conducted by NASA's Ames Research Center, the technology developed for astronaut needs has been adapted to portable cooling systems which will permit two youngsters to lead more normal lives.

  16. Novel solar tower structure to lower plant cost and construction risk

    Peterseim, J. H.; White, S.; Hellwig, U.


    In recent times the interest in solar tower power plants is increasing with various plants being built in the last years and currently under construction, e.g. Ivanpah and Crescent Dunes in the US and Khi Solar One in South Africa. The higher cycle efficiency leads to lower levelised cost of electricity. However, further cost reductions are required and this paper compares a novel and patented solar tower structure with a conventional concrete tower. The novel solar tower design is cable-stayed which has the benefit that the cables absorb a large part of the wind and buckling loads. A tower that has to cope with fewer wind and buckling forces can have a significantly smaller diameter than a concrete tower, which enables workshop manufacture, sea and road transport, and rapid on-site installation. The case study provided in this paper finds that the tower area affected by wind can be reduced by up to 45%, installation time shortened by up to 66%, and tower cost by 20-40%. The novel design allows the construction and transport of the solar tower in few large modules, which are pre-manufactured including piping, cables, platform, ladders etc. The few modules can be assembled and installed rapidly not only lowering plant cost and construction time but also project risk.

  17. Justifying plans to improve performance of an existing cooling system

    Burns, J. [Stone & Webster Engineering Corp., Boston, MA (United States); Godard, D.; Randall, R. [Niagara-Mohawk Power Company, Syracuse, NY (United States); Cooper, J. [Cooper & Associates, P.A., Tampa, FL (United States)


    This paper discusses the kinds of quantitative justification needed to convince today`s cost-conscious, informed utility management that proposed improvements to the cooling system are feasible and will be of strong economic benefit to the station. It summarizes the evaluations developed during the review of circulating water system improvement candidates that accompanied the recent 4.5% power uprate of an existing large station with a closed cycle cooling system which utilizes a natural draft cooling tower. Presented in the paper are the capital costs and turbine performance improvements related to: air blanketing reduction by baffle plate additions to the condenser air coolers; minimizing costs of waterbox/bundle cleaning programs; cooling system performance monitoring enhancements; the prudency of tube staking after uprate; the benefits of a circulating water flow increase; better cooling tower hot water distribution; adding a layer of fill to the cooling tower; and finally the value of a helper tower. Considered too in this paper are the performance test surveys of both the condenser and cooling tower that identified the cause and/or performance deficiencies. The general principles to be discussed will be applicable to all sizes and types of power plant cooling systems. The paper however, will focus on the 1994-1995 case study of a 675,000 GPM closed cooling system with a 537 ft. counterflow natural draft cooling tower and a 670,000 sq. ft. six bundle single pass condenser which serves the six flow low pressure (LP) turbine of an 1100 MW nuclear plant. One example of the outcome of the program was an approximate 20% increase in condenser cleanliness from 55% to 75%. 9 refs., 7 figs.

  18. Use of Air2Air Technology to Recover Fresh-Water from the Normal Evaporative Cooling Loss at Coal-Based Thermoelectric Power Plants

    Ken Mortensen


    This program was undertaken to build and operate the first Air2Air{trademark} Water Conservation Cooling Tower at a power plant, giving a validated basis and capability for water conservation by this method. Air2Air{trademark} water conservation technology recovers a portion of the traditional cooling tower evaporate. The Condensing Module provides an air-to-air heat exchanger above the wet fill media, extracting the heat from the hot saturated moist air leaving in the cooling tower and condensing water. The rate of evaporate water recovery is typically 10%-25% annually, depending on the cooling tower location (climate).

  19. One-year dynamic monitoring of a masonry tower

    Guidobaldi Marco


    Full Text Available The paper presents some results of the continuous dynamic monitoring program carried out on the tallest historic tower in Mantua, Italy. This project follows an extensive diagnostic investigation aimed at assessing the structural condition of the tower after the Italian earthquakes of May 2012. A simple dynamic monitoring system was permanently installed in the upper part of the building and automatic modal identification was performed. The results allow to evaluate the effects of changing temperature on automatically identified natural frequencies, to verify the practical feasibility of damage detection methods based on natural frequencies shifts and provide clear evidence of the possible key role of continuous dynamic monitoring in the preventive conservation of historic towers.

  20. A modular restoration tower for electric power line transmission

    Nicolazzi, L.C.; Pereira, J.C.; Leonel, C.E.L.; Rocha, G.B.; Bianchezzi, V.; Mendes, F. [Universidade Federal Santa Catarina (UFSC), Florianopolis, SC (Brazil). Dept. de Engenharia Mecanica], Emails:,; Luz, R.L. [ELETROSUL Centrais Eletricas S.A., Florianopolis, SC (Brazil)], Email:


    The main target of this R and D project is to develop an restoration tower for electric energy lines transmission. Whereas these towers should present the main features like transport facility, easiest assembling associated with a low cost of manufacture, it was applied the single-column tower concepts supported by stays, modularized, framed and articulated at the base. The concepts used for this development was a design methodology. From the different definition situations of load, numerical models have been developed focusing the design to the best of structural element arrangements of its modules. Then, tests were performed in laboratory to determine the module structural performance for different work load situations. These tests served to identify inconsistencies in the numerical models and proposed adjustments in its design to improve its performance on the strength and stability. (author)

  1. Ozonation of cooling water prevents biofilms and legionella. Hygiene; Kuehlwasserbehandlung mit Ozon haelt Biofilme und Legionellen in Schach. Hygiene

    Hackl, W.; Hoffmann, M. [BWT Wassertechnik GmbH, Schriesheim (Germany). Forschung und Entwicklung


    Legionella in plumes of evaporation cooling towers have often caused serious illnesses and even deaths. To prevent the growth of microorganisms in cooling towers, operators often use hazardous and toxic biocides or chlorine. There is an ecologically and also technically efficient alternative: In the Briey plant of the international Norma group, biofilm and legionella prophylaxis is achieved by ozonation. (orig.)

  2. The Tower Shielding Facility: Its glorious past

    Muckenthaler, F.J.


    The Tower Shielding Facility (TSF) is the only reactor facility in the US that was designed and built for radiation-shielding studies in which both the reactor source and shield samples could be raised into the air to allow measurements to be made without interference from ground scattering or other spurious effects. The TSF proved its usefulness as many different programs were successfully completed. It became active in work for the Defense Atomic Support Agency (DASA) Space Nuclear Auxiliary Power, Defense Nuclear Agency, Liquid Metal Fast Breeder Reactor Program, the Gas-Cooled and High-Temperature Gas-Cooled Reactor programs, and the Japanese-American Shielding Program of Experimental Research, just to mention a few of the more extensive ones. The history of the TSF as presented in this report describes the various experiments that were performed using the different reactors. The experiments are categorized as to the programs which they supported and placed in corresponding chapters. The experiments are described in modest detail, along with their purpose when appropriate. Discussion of the results is minimal, but references are given to more extensive topical reports.

  3. Survey of power tower technology

    Hildebrandt, A. F.; Dasgupta, S.


    The history of the power tower programs is reviewed, and attention is given to the current state of heliostat, receiver, and storage design. Economic considerations are discussed, as are simulation studies and implications. Also dealt with are alternate applications for the power tower and some financing and energy aspects of solar electric conversion. It is noted that with a national commitment to solar energy, the power tower concept could generate 40 GW of electricity and double this amount in process heat by the year 2000. Calculations show an energy amplification factor of 20 for solar energy plants; that is, the ratio of the electric energy produced over the lifetime of a power plant to the thermal energy required to produce the plant.

  4. Initial Cooling Experiment (ICE)

    Photographic Service


    In 1977, in a record-time of 9 months, the magnets of the g-2 experiment were modified and used to build a proton/antiproton storage ring: the "Initial Cooling Experiment" (ICE). It served for the verification of the cooling methods to be used for the "Antiproton Project". Stochastic cooling was proven the same year, electron cooling followed later. Also, with ICE the experimental lower limit for the antiproton lifetime was raised by 9 orders of magnitude: from 2 microseconds to 32 hours. For its previous life as g-2 storage ring, see 7405430. More on ICE: 7711282, 7809081, 7908242.

  5. High energy electron cooling

    Parkhomchuk, V. [Budker Institute of Nuclear Physics, Novosibirsk (Russian Federation)


    High energy electron cooling requires a very cold electron beam. The questions of using electron cooling with and without a magnetic field are presented for discussion at this workshop. The electron cooling method was suggested by G. Budker in the middle sixties. The original idea of the electron cooling was published in 1966. The design activities for the NAP-M project was started in November 1971 and the first run using a proton beam occurred in September 1973. The first experiment with both electron and proton beams was started in May 1974. In this experiment good result was achieved very close to theoretical prediction for a usual two component plasma heat exchange.

  6. Report of the George A. Towns Elementary School solar heating and cooling project, Atlanta, Georgia. United States special format report


    The design, construction, and performance analysis of an experimental solar heating and cooling system to accommodate a building of approximately 3,000 m/sup 2/ in area are described. The objectives of the experiment are to: make a significant contribution to solar design, technology, and acceptability; conduct an advanced experiment on an integrated large-scale solar heating and cooling system, determine its performance, reliability, and maintainability, and compare these actual results with predicted performance; identify subsystem interface problems that cannot adequately be predicted by theoretical analysis; operationally test major components and identify improvements required; and identify cost reducing materials and techniques which may improve the economic viability of solar heating and cooling systems. (WDM)

  7. Modelling of Bending of Windturbine Tower

    Andersen, Kurt


    Describes a model of a windturbine tower's transverse oscillation depending of turbulence in the wind.......Describes a model of a windturbine tower's transverse oscillation depending of turbulence in the wind....



    ICE was built in 1977, using the modified bending magnets of the g-2 muon storage ring (see 7405430). Its purpose was to verify the validity of stochastic and electron cooling for the antiproton project. Stochastic cooling proved a resounding success early in 1978 and the antiproton project could go ahead, now entirely based on stochastic cooling. Electron cooling was experimented with in 1979. The 26 kV equipment is housed in the cage to the left of the picture, adjacent to the "e-cooler" located in a straight section of the ring. With some modifications, the cooler was later transplanted into LEAR (Low Energy Antiproton Ring) and then, with further modifications, into the AD (Antiproton Decelerator), where it cools antiprotons to this day (2006). See also: 7711282, 7802099, 7809081.



    ICE was built in 1977, in a record time of 9 months, using the modified bending magnets of the g-2 muon storage ring. Its purpose was to verify the validity of stochastic and electron cooling for the antiproton project, to be launched in 1978. Already early in 1978, stochastic cooling proved a resounding success, such that the antiproton (p-pbar)project was entirely based on it. Tests of electron cooling followed later: protons of 46 MeV kinetic energy were cooled with an electron beam of 26 kV and 1.3 A. The cage seen prominently in the foreground houses the HV equipment, adjacent to the "cooler" installed in a straight section of the ring. With some modifications, the cooler was later transplanted into LEAR (Low Energy Antiproton Ring) and then, with further modifications, into the AD (Antiproton Decelerator), where it cools antiprotons to this day (2006). See also: 7711282, 7802099, 7908242.

  10. Hexcrete Tower for Harvesting Wind Energy at Taller Hub Heights - Budget Period 2

    Sritharan, Sri [Iowa State Univ., Ames, IA (United States)


    Interest in designing taller towers for wind energy production in the United States (U.S.) has been steadily growing. In May 2015, it was revealed that taller towers will make wind energy production a reality in all 50 states, including some states that have nearly zero renewables in their energy portfolio. Facilitating wind energy production feasibility in all 50 states will no doubt contribute to increasing the electricity produced by wind from 4.5% in 2013 to a targeted scenario of 35% by 2050 in the Wind Vision report. This project focuses on the Hexcrete tower concept developed for tall towers using High Strength Concrete (HSC) and/or Ultra-High Performance Concrete (UHPC). Among other benefits, the Hexcrete concept overcomes transportation and logistical challenges, thus facilitating construction of towers with hub heights of 100-m (328-ft) and higher. The goal of this project is to facilitate widespread deployment of Hexcrete towers for harvesting wind energy at 120 to 140-m (394 to 459-ft) hub heights and reduce the Levelized Cost of Energy (LCOE) of wind energy production in the U.S. The technical scope of the project includes detailed design and optimization of at least three wind turbine towers using the Hexcrete concept together with experimental validation and LCOE analyses and development of a commercialization plan.

  11. 76 FR 490 - Marking Meteorological Evaluation Towers


    ... Federal Aviation Administration 14 CFR Part 77 Marking Meteorological Evaluation Towers AGENCY: Federal.... SUMMARY: The FAA is considering revising its current Advisory Circular on Obstruction Marking and Lighting to include guidance for Meteorological Evaluation Towers (METs). These towers are erected in...

  12. The solar towers of Chankillo

    Sparavigna, Amelia Carolina


    An ancient solar observatory is composed by thirteen towers lined on a hill of a coastal desert of Peru. This is the Chankillo observatory. Here we discuss it, showing some simulations of the local sun direction. An analysis of the behaviour of shadows is also proposed.

  13. Good towers of function Fields

    Nguyen, Nhut

    of q. In this thesis, we study a construction using Drinfeld modules that produces explicitly defined families of algebraic curves that asymptotically achieve Ihara’s constant. Such families of curves can also be described using towers of function fields. Restated in this language the aim...

  14. Stochastic Cooling

    Blaskiewicz, M.


    Stochastic Cooling was invented by Simon van der Meer and was demonstrated at the CERN ISR and ICE (Initial Cooling Experiment). Operational systems were developed at Fermilab and CERN. A complete theory of cooling of unbunched beams was developed, and was applied at CERN and Fermilab. Several new and existing rings employ coasting beam cooling. Bunched beam cooling was demonstrated in ICE and has been observed in several rings designed for coasting beam cooling. High energy bunched beams have proven more difficult. Signal suppression was achieved in the Tevatron, though operational cooling was not pursued at Fermilab. Longitudinal cooling was achieved in the RHIC collider. More recently a vertical cooling system in RHIC cooled both transverse dimensions via betatron coupling.

  15. Solar Power Tower Design Basis Document, Revision 0



    This report contains the design basis for a generic molten-salt solar power tower. A solar power tower uses a field of tracking mirrors (heliostats) that redirect sunlight on to a centrally located receiver mounted on top a tower, which absorbs the concentrated sunlight. Molten nitrate salt, pumped from a tank at ground level, absorbs the sunlight, heating it up to 565 C. The heated salt flows back to ground level into another tank where it is stored, then pumped through a steam generator to produce steam and make electricity. This report establishes a set of criteria upon which the next generation of solar power towers will be designed. The report contains detailed criteria for each of the major systems: Collector System, Receiver System, Thermal Storage System, Steam Generator System, Master Control System, and Electric Heat Tracing System. The Electric Power Generation System and Balance of Plant discussions are limited to interface requirements. This design basis builds on the extensive experience gained from the Solar Two project and includes potential design innovations that will improve reliability and lower technical risk. This design basis document is a living document and contains several areas that require trade-studies and design analysis to fully complete the design basis. Project- and site-specific conditions and requirements will also resolve open To Be Determined issues.

  16. The shape of the Eiffel Tower

    Gallant, Joseph


    The distinctive shape of the Eiffel Tower is based on simple physics and is designed so that the maximum torque created by the wind is balanced by the torque due to the Tower's weight. We use this idea to generate an equation for the shape of the Tower. The solution depends only on the width of the base and the maximum wind pressure. We parametrize the wind pressure and reproduce the shape of the Tower. We also discuss some of the Tower's interesting history and characteristics.

  17. Analysis of radiological accident emissions of a lead-cooled experimental reactor. LEADER Project; Analisis radiologico de las emisiones en caso de accidente de un reactor experimental refrigerado por plomo. Proyecto LEADER

    Gomez Salcedo, F.; Cortes Martin, A.


    The LEADER project develops a conceptual level industrial size reactor cooled lead and a demonstration plant of this technology. The project objectives are to define the characteristics and design to installation scale reactor using available technologies and short-term components and assess safety aspects conducting a preliminary analysis of the impact of the facility.

  18. The Metric Documentation of Cham Towers in Vietnam by Spherical Photogrammetry

    Fangi, G.; Malinverni, E. S.; Tassetti, A. N.


    The Università Politecnica delle Marche is charged of the study, survey and documentation of the Chan towers in Vietnam. The towers are spread near the coastline from latitude 16° 30', to latitude of 10° 56'. The Champa civilization flourished from 8th century till 17th century produced the Cham towers, places of religious worship. The ancient Cham people created a developed culture expressed in the architecture in the towers, which were Buddhist temples. Roughly there are six different architectonic styles and two different layouts in plan. One lay-out is that one main tower is surrounded by smaller service buildings, like walls, doors, gates; the other layout is a set of three aligned towers. We carried out the documentation with three different techniques, laser scanning, dense point clouds generation with SfM (Structure from Motion) algorithm, and mainly by Panoramic Spherical Photogrammetry (PSP). Laser scanning is indeed the best instrument but sometimes its availability is very limited for different practical and logistic reasons. The point cloud generation produced good results, but it has some problems and limitations of management too. On the other hand PSP is very quick technique in the taking phase, but the restitution is rather slow. PSP is suitable for a good metric documentation, making the Cham tower project the main project of documentation executed with spherical photogrammetry.

  19. Laboratory Experiment and Numerical Analysis of a New Type of Solar Tower Efficiently Generating a Thermal Updraft

    Yuji Ohya


    Full Text Available A new type of solar tower was developed through laboratory experiments and numerical analyses. The solar tower mainly consists of three components. The transparent collector area is an aboveground glass roof, with increasing height toward the center. Attached to the center of the inside of the collector is a vertical tower within which a wind turbine is mounted at the lower entry to the tower. When solar radiation heats the ground through the glass roof, ascending warm air is guided to the center and into the tower. A solar tower that can generate electricity using a simple structure that enables easy and less costly maintenance has considerable advantages. However, conversion efficiency from sunshine energy to mechanical turbine energy is very low. Aiming to improve this efficiency, the research project developed a diffuser-type tower instead of a cylindrical tower, and investigated a suitable diffuser shape for practical use. After changing the tower height and diffuser open angle, with a temperature difference between the ambient air aloft and within the collector, various diffuser tower shapes were tested by laboratory experiments and numerical analyses. As a result, it was found that a diffuser tower with a semi-open angle of 4° is an optimal shape, producing the fastest updraft at each temperature difference in both the laboratory experiments and numerical analyses. The relationships between thermal updraft speed and temperature difference and/or tower height were confirmed. It was found that the thermal updraft velocity is proportional to the square root of the tower height and/or temperature difference.

  20. Irreducibility of The Igusa Tower

    Haruzo HIDA


    We shall give a simple (basically) purely in characteristic p proof of the irreducibility of the Igusa tower over Shimura varieties of PEL type. Our result covers Shimura variety of type A and type C classical groups, in particular, the Siegel modular varieties, the Hilbert-Siegel modular varieties, Picard surfaces and Shimura varieties of inner forms of unitary and symplectic groups over totally real fields.

  1. Hybrid Tower, Designing Soft Structures

    Ramsgaard Thomsen, Mette; Tamke, Martin; Holden Deleuran, Anders;


    predictions about the inherent interdependency and material dependent performance of the hybrid structure and (2) the inter-scalar design strategies for specification and fabrication. The first investigation focuses on the design pipelines developed between the implementation of realtime physics...... (membrane reinforcement strategy) and micro scale (design of bespoke textile membrane). The paper concludes with a post construction analysis. Comparing structural and environmental data, the predicted and the actual performance of tower are evaluated and discussed....

  2. Self-assembled granular towers

    Pacheco-Vazquez, Felipe; Moreau, Florian; Vandewalle, Nicolas; Dorbolo, Stephan; GroupResearch; Applications in Statistical Physics Team


    When some water is added to sand, cohesion among the grains is induced. In fact, only 1% of liquid volume respect to the total pore space of the sand is necessary to built impressive sandcastles. Inspired on this experience, the mechanical properties of wet piles and sand columns have been widely studied during the last years. However, most of these studies only consider wet materials with less than 35% of liquid volume. Here we report the spontaneous formation of granular towers produced when dry sand is poured on a highly wet sand bed: The impacting grains stick on the wet grains due to instantaneous liquid bridges created during the impact. The grains become wet by the capillary ascension of water and the process continues, giving rise to stable narrow sand towers. Actually, the towers can reach the maximum theoretical limit of stability predicted by previous models, only expected for low liquid volumes. The authors would like to thank FNRS and Conacyt Mexico for financial support. FPV is a beneficiary of a movility grant from BELSPO/Marie Curie and the University of Liege.

  3. Cooling with Superfluid Helium

    Lebrun, P


    The technical properties of helium II (‘superfluid’ helium) are presented in view of its applications to the cooling of superconducting devices, particularly in particle accelerators. Cooling schemes are discussed in terms of heat transfer performance and limitations. Large-capacity refrigeration techniques below 2 K are reviewed, with regard to thermodynamic cycles as well as process machinery. Examples drawn from existing or planned projects illustrate the presentation. Keywords: superfluid helium, cryogenics

  4. A Refined Model for the Behavior of Nitrous Oxide to Assess the Limits of N2O Cooling Project

    National Aeronautics and Space Administration — The proposed project is crucial to enabling safe flight research on a rocket nozzle that is based on our recent innovation, which is to use the refrigerant...

  5. 'Towers in the Tempest' Computer Animation Submission

    Shirah, Greg


    The following describes a computer animation that has been submitted to the ACM/SIGGRAPH 2008 computer graphics conference: 'Towers in the Tempest' clearly communicates recent scientific research into how hurricanes intensify. This intensification can be caused by a phenomenon called a 'hot tower.' For the first time, research meteorologists have run complex atmospheric simulations at a very fine temporal resolution of 3 minutes. Combining this simulation data with satellite observations enables detailed study of 'hot towers.' The science of 'hot towers' is described using: satellite observation data, conceptual illustrations, and a volumetric atmospheric simulation data. The movie starts by showing a 'hot tower' observed by NASA's Tropical Rainfall Measuring Mission (TRMM) spacecraft's three dimensional precipitation radar data of Hurricane Bonnie. Next, the dynamics of a hurricane and the formation of 'hot towers' are briefly explained using conceptual illustrations. Finally, volumetric cloud, wind, and vorticity data from a supercomputer simulation of Hurricane Bonnie are shown using volume techniques such as ray marching.

  6. Evaluating transmission towers potentials during ground faults


    During ground faults on transmission lines, a number of towers near the fault are likely to acquire high potentials to ground. These tower voltages, if excessive, may present a hazard to humans and animals. This paper presents analytical methods in order to determine the transmission towers potentials during ground faults, for long and short lines. The author developed a global systematic approach to calculate these voltages, which are dependent of a number of factors. Some of the most important factors are: magnitudes of fault currents, fault location with respect to the line terminals, conductor arrangement on the tower and the location of the faulted phase, the ground resistance of the faulted tower, soil resistivity, number, material and size of ground wires. The effects of these factors on the faulted tower voltages have been also examined for different types of power lines.

  7. Spent nuclear fuel project cold vacuum drying facility tempered water and tempered water cooling system design description

    IRWIN, J.J.


    This document provides the System Design Description (SDD) for the Cold Vacuum Drying Facility (CVDF) Tempered Water (TW) and Tempered Water Cooling (TWC) System . The SDD was developed in conjunction with HNF-SD-SNF-SAR-002, Safety Analysis Report for the Cold Vacuum Drying Facility, Phase 2, Supporting Installation of Processing Systems (Garvin 1998), The HNF-SD-SNF-DRD-O02, 1998, Cold Vacuum Drying Facility Design Requirements, and the CVDF Design Summary Report. The SDD contains general descriptions of the TW and TWC equipment, the system functions, requirements and interfaces. The SDD provides references for design and fabrication details, operation sequences and maintenance. This SOD has been developed for the SNFP Operations Organization and shall be updated, expanded, and revised in accordance with future design, construction and startup phases of the CVDF until the CVDF final ORR is approved.


    杨秉钧; 焦勇; 徐德林; 付雅娣


    The Watch Tower Project in Beijing Olympic Park is a high-rise steel structure with a huge volume. After careful calculation, it is determined to use steel sheet composite shear wall structure, which could not only bear the load of upper part, but also integrate with the tower base to stabilize the tower body. Under precondition of ensuring structure safety, building functions are successfully realized and ideal application effects are obtained through adoption of a series construction techniques, including steel column installation, steel sheet wall installation, steel bar binding, formwork installation, concrete pouring, formwork dismantlement and next steel bar binding, as well as successful disposal of difficulties in connection between steel bar and steel sheet.%北京奥林匹克公园瞭望塔工程为高耸钢结构,塔体总量很大,经过详细计算,决定采用钢板组合剪力墙结构,既能承受上部荷载,还能与塔座组成整体形成对塔身的嵌固.通过采取钢柱安装、钢板墙安装、钢筋绑扎、模板安装、混凝土浇筑、模板拆除、下一步钢筋绑扎等一系列施工技术,以及对钢筋与钢板之间的连接这一难点问题进行处理,在保证结构安全性的前提下,很好地实现了建筑功能,取得了理想的应用效果.

  9. Improvement to Air2Air Technology to Reduce Fresh-Water Evaporative Cooling Loss at Coal-Based Thermoelectric Power Plants

    Ken Mortensen


    This program was undertaken to enhance the manufacturability, constructability, and cost of the Air2Air{TM} Water Conservation and Plume Abatement Cooling Tower, giving a validated cost basis and capability. Air2Air{TM} water conservation technology recovers a portion of the traditional cooling tower evaporate. The Condensing Module provides an air-to-air heat exchanger above the wet fill media, extracting the heat from the hot saturated moist air leaving in the cooling tower and condensing water. The rate of evaporate water recovery is typically 10% - 25% annually, depending on the cooling tower location (climate). This program improved the efficiency and cost of the Air2Air{TM} Water Conservation Cooling Tower capability, and led to the first commercial sale of the product, as described.

  10. Cellular Phone Towers, Cell Towers, Published in unknown, Norton County Appraisal Office.

    NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, was produced all or in part from Other information as of unknown. It is described as 'Cell Towers'. Data by this publisher are...

  11. An Optimal Unramified Tower of Function Fields

    Efficient construction of long AG--codes resulting from optimal towers of function fields is known to be difficult. In the following a tower which is both optimal and unramified, that is a tower in which all places are unramified after some level, is investigated in the hope that its simple ramif...... ramification structure can be exploited in the construction of AG--codes. Results are mostly negative, but helps clarifying the difficulties in computing bases of Riemann--Roch spaces....

  12. The effect analysis of strain rate on power transmission tower-line system under seismic excitation.

    Tian, Li; Wang, Wenming; Qian, Hui


    The effect analysis of strain rate on power transmission tower-line system under seismic excitation is studied in this paper. A three-dimensional finite element model of a transmission tower-line system is created based on a real project. Using theoretical analysis and numerical simulation, incremental dynamic analysis of the power transmission tower-line system is conducted to investigate the effect of strain rate on the nonlinear responses of the transmission tower and line. The results show that the effect of strain rate on the transmission tower generally decreases the maximum top displacements, but it would increase the maximum base shear forces, and thus it is necessary to consider the effect of strain rate on the seismic analysis of the transmission tower. The effect of strain rate could be ignored for the seismic analysis of the conductors and ground lines, but the responses of the ground lines considering strain rate effect are larger than those of the conductors. The results could provide a reference for the seismic design of the transmission tower-line system.

  13. Seismic response of a full-scale wind turbine tower using experimental and numerical modal analysis

    Kandil, Kamel Sayed Ahmad; Saudi, Ghada N.; Eltaly, Boshra Aboul-Anen; El-khier, Mostafa Mahmoud Abo


    Wind turbine technology has developed tremendously over the past years. In Egypt, the Zafarana wind farm is currently generating at a capacity of 517 MW, making it one of the largest onshore wind farms in the world. It is located in an active seismic zone along the west side of the Gulf of Suez. Accordingly, seismic risk assessment is demanded for studying the structural integrity of wind towers under expected seismic hazard events. In the context of ongoing joint Egypt-US research project "Seismic Risk Assessment of Wind Turbine Towers in Zafarana wind Farm Egypt" (Project ID: 4588), this paper describes the dynamic performance investigation of an existing Nordex N43 wind turbine tower. Both experimental and numerical work are illustrated explaining the methodology adopted to investigate the dynamic behavior of the tower under seismic load. Field dynamic testing of the full-scale tower was performed using ambient vibration techniques (AVT). Both frequency domain and time domain methods were utilized to identify the actual dynamic properties of the tower as built in the site. Mainly, the natural frequencies, their corresponding mode shapes and damping ratios of the tower were successfully identified using AVT. A vibration-based finite element model (FEM) was constructed using ANSYS V.12 software. The numerical and experimental results of modal analysis were both compared for matching purpose. Using different simulation considerations, the initial FEM was updated to finally match the experimental results with good agreement. Using the final updated FEM, the response of the tower under the AQABA earthquake excitation was investigated. Time history analysis was conducted to define the seismic response of the tower in terms of the structural stresses and displacements. This work is considered as one of the pioneer structural studies of the wind turbine towers in Egypt. Identification of the actual dynamic properties of the existing tower was successfully performed

  14. Seismic response of a full-scale wind turbine tower using experimental and numerical modal analysis

    Kandil, Kamel Sayed Ahmad; Saudi, Ghada N.; Eltaly, Boshra Aboul-Anen; El-khier, Mostafa Mahmoud Abo


    Wind turbine technology has developed tremendously over the past years. In Egypt, the Zafarana wind farm is currently generating at a capacity of 517 MW, making it one of the largest onshore wind farms in the world. It is located in an active seismic zone along the west side of the Gulf of Suez. Accordingly, seismic risk assessment is demanded for studying the structural integrity of wind towers under expected seismic hazard events. In the context of ongoing joint Egypt-US research project "Seismic Risk Assessment of Wind Turbine Towers in Zafarana wind Farm Egypt" (Project ID: 4588), this paper describes the dynamic performance investigation of an existing Nordex N43 wind turbine tower. Both experimental and numerical work are illustrated explaining the methodology adopted to investigate the dynamic behavior of the tower under seismic load. Field dynamic testing of the full-scale tower was performed using ambient vibration techniques (AVT). Both frequency domain and time domain methods were utilized to identify the actual dynamic properties of the tower as built in the site. Mainly, the natural frequencies, their corresponding mode shapes and damping ratios of the tower were successfully identified using AVT. A vibration-based finite element model (FEM) was constructed using ANSYS V.12 software. The numerical and experimental results of modal analysis were both compared for matching purpose. Using different simulation considerations, the initial FEM was updated to finally match the experimental results with good agreement. Using the final updated FEM, the response of the tower under the AQABA earthquake excitation was investigated. Time history analysis was conducted to define the seismic response of the tower in terms of the structural stresses and displacements. This work is considered as one of the pioneer structural studies of the wind turbine towers in Egypt. Identification of the actual dynamic properties of the existing tower was successfully performed

  15. 多塔结构的等效单塔抗震计算方法%Equivalent Single Tower Method for Aseismic Design of Multi-tower Structure



    针对多塔高层超限结构抗震验算计算量大的问题,提出了一种多塔结构等效为单塔结构的验算思路。通过多塔结构和单塔结构的振型周期和基底剪力的计算结果的比较,得到了等效单塔结构的地震响应偏差,从而在单塔结构的计算结果的基础上加上偏差以包络多塔结果,达到快速可靠地验算多塔结构的目的,同时保证了安全性。上海真如副中心的两栋超限结构的抗震验算的实例中采用了本文提出的方法,结果表明该工程的设计符合规范要求,达到预计的抗震目标。%To address the issue of large amount of calculation for aseismic design of multi-tower high-rise structure, an equivalent single tower method is suggested in this paper. Through comparing the periods of the vibration modes and the base shear between the single tower and multi-tower, the response deviation of the result is estimated. The estimated deviation is added to the response of the single tower to cover the response of multi-tower, thus to ensure safety and reliability. The application of the two towers in the Shanghai Zhenru sub-center shows that the proposed method is capable for multi-tower structures, and that the design of the project meets the requirements of the code.

  16. The ACS LCID project. X. The Star Formation History of IC 1613: Revisiting the Over-Cooling Problem

    Skillman, Evan D; Weisz, Daniel R; Monelli, Matteo; Gallart, Carme; Aparicio, Antonio; Bernard, Edouard J; Boylan-Kolchin, Michael; Cassisi, Santi; Cole, Andrew A; Dolphin, Andrew E; Ferguson, Henry C; Mayer, Lucio; Navarro, Julio F; Stetson, Peter B; Tolstoy, Eline


    We present an analysis of the star formation history (SFH) of a field near the half light radius in the Local Group dwarf irregular galaxy IC 1613 based on deep Hubble Space Telescope Advanced Camera for Surveys imaging. Our observations reach the oldest main sequence turn-off, allowing a time resolution at the oldest ages of ~1 Gyr. Our analysis shows that the SFH of the observed field in IC 1613 is consistent with being constant over the entire lifetime of the galaxy. These observations rule out an early dominant episode of star formation in IC 1613. We compare the SFH of IC 1613 with expectations from cosmological models. Since most of the mass is in place at early times for low mass halos, a naive expectation is that most of the star formation should have taken place at early times. Models in which star formation follows mass accretion result in too many stars formed early and gas mass fractions which are too low today (the "over-cooling problem"). The depth of the present photometry of IC 1613 shows that...

  17. The ACS LCID project. X. the star formation history of IC 1613: Revisiting the over-cooling problem

    Skillman, Evan D. [Minnesota Institute for Astrophysics, University of Minnesota, Minneapolis, MN 55455 (United States); Hidalgo, Sebastian L.; Monelli, Matteo; Gallart, Carme; Aparicio, Antonio, E-mail:, E-mail:, E-mail:, E-mail:, E-mail: [Instituto de Astrofísica de Canarias, Vía Láctea s/n, E-38200 La Laguna, Tenerife, Canary Islands (Spain); and others


    We present an analysis of the star formation history (SFH) of a field near the half-light radius in the Local Group dwarf irregular galaxy IC 1613 based on deep Hubble Space Telescope Advanced Camera for Surveys imaging. Our observations reach the oldest main sequence turn-off, allowing a time resolution at the oldest ages of ∼1 Gyr. Our analysis shows that the SFH of the observed field in IC 1613 is consistent with being constant over the entire lifetime of the galaxy. These observations rule out an early dominant episode of star formation in IC 1613. We compare the SFH of IC 1613 with expectations from cosmological models. Since most of the mass is in place at early times for low-mass halos, a naive expectation is that most of the star formation should have taken place at early times. Models in which star formation follows mass accretion result in too many stars formed early and gas mass fractions that are too low today (the 'over-cooling problem'). The depth of the present photometry of IC 1613 shows that, at a resolution of ∼1 Gyr, the star formation rate is consistent with being constant, at even the earliest times, which is difficult to achieve in models where star formation follows mass assembly.

  18. Validation of the dynamic wake meander model with focus on tower loads

    Larsen, Torben J.; Larsen, Gunner Chr.; Pedersen, Mads Mølgaard


    of wind speeds. In general, tower loads in wake conditions are very challenging to predict correctly in simulations. The Nysted project offers an improved insight to this field as six wind turbines located in the Nysted II wind farm have been instrumented to measure tower top and tower bottom moments. All...... a period extending over a time span of more than 3 years. Based on the recorded data basic mechanisms driving the increased loading experienced by wind turbines operating in offshore wind farm conditions have been identified, characterized and modeled. The modeling is based on the Dynamic Wake Meandering...... (DWM) approach in combination with the state-of-the-art aeroelastic model HAWC2, and has previously as well as in this study shown good agreement with the measurements. The conclusions from the study have several parts. In general the tower bending and yaw loads show a good agreement between...

  19. Solar assisted ventilation tower, Frederiksberg[Denmark]; Ventilationsanlaeggenes betydning for ejendommens varmeforbrug. Delrapport 1



    The project has demonstrated a building integrated ventilation system with the ducts system installed outside the facade. The air ducts are installed in a solar tower parallel to the staircases in the courtyard. The towers utilise the solar energy for preheating the ventilation air. An air handling unit with counterflow heat exchanger is installed in the roof space. The system is designed for old building block, which are going to be renovated with mechanical ventilation. The system saves room space for the installations of the ventilation ducts. The monitoring of the system performance shows energy saving of 40% caused by new windows, individual heat meters and ventilation with heat recovery and solar tower. The system efficiency of the solar tower is high compared with other traditional solar wall constructions. The ventilation system is designed with a very low electricity consumption of the fans. The monitored electricity consumption is 22 W per dwellings. (au)

  20. KM3NeT tower data acquisition and data transport electronics

    Nicolau, C. A.; Ameli, F.; Biagioni, A.; Capone, A.; Frezza, O.; Lonardo, A.; Masullo, R.; Mollo, C. M.; Orlando, A.; Simeone, F.; Vicini, P.


    In the framework of the KM3Net European project, the production stage of a large volume underwater neutrino telescope has started. The forthcoming installation includes 8 towers and 24 strings, that will be installed 100 km off-shore Capo Passero (Italy) at 3500 m depth. The KM3NeT tower, whose layout is strongly based on the NEMO Phase-2 prototype tower deployed in March 2013, has been re-engineered and partially re-designed in order to optimize production costs, power consumption, and usability. This contribution gives a description of the main electronics, including front-end, data transport and clock distribution system, of the KM3NeT tower detection unit.

  1. KM3NeT tower data acquisition and data transport electronics

    Nicolau C.A.


    Full Text Available In the framework of the KM3Net European project, the production stage of a large volume underwater neutrino telescope has started. The forthcoming installation includes 8 towers and 24 strings, that will be installed 100 km off-shore Capo Passero (Italy at 3500 m depth. The KM3NeT tower, whose layout is strongly based on the NEMO Phase-2 prototype tower deployed in March 2013, has been re-engineered and partially re-designed in order to optimize production costs, power consumption, and usability. This contribution gives a description of the main electronics, including front-end, data transport and clock distribution system, of the KM3NeT tower detection unit.

  2. Green towers and green walls

    Sharp, R. [Sharp and Diamond Landscape Architecture and Planning, Vancouver, BC (Canada)


    North American cities face many major environmental and health issues such as urban heat island effect, the intensity of storms, microclimate around buildings, imperviousness of sites, poor air quality and increases in respiratory disease. Several new technologies are starting to address global impacts and community level issues as well as the personal health and comfort of building occupants. These include green towers, living walls, vegetated rooftops and ecological site developments. This paper examined these forms of eco-development and presented their benefits. It discussed green walls in Japan; green towers in Malaysia, Singapore and Great Britain; green facades of climbing plants; active living walls in Canada; and passive living walls in France and Canada. It also discussed thermal walls; thematic walls; vertical gardens and structured wildlife habitat. Last, it presented testing, monitoring, research and conclusions. The Centre for the Advancement of Green Roof Technology is setting up a program to test thermal performance, to assess plant survival and to monitor green walls at the British Columbia Institute of Technology in Vancouver, Canada as much of the research out of Japan is only available in Japanese script. It was concluded that green architecture can provide shade, food, rainwater, shelter for wildlife and mimic natural systems. 15 refs.

  3. Wind turbine tower for storing hydrogen and energy

    Fingersh, Lee Jay [Westminster, CO


    A wind turbine tower assembly for storing compressed gas such as hydrogen. The tower assembly includes a wind turbine having a rotor, a generator driven by the rotor, and a nacelle housing the generator. The tower assembly includes a foundation and a tubular tower with one end mounted to the foundation and another end attached to the nacelle. The tower includes an in-tower storage configured for storing a pressurized gas and defined at least in part by inner surfaces of the tower wall. In one embodiment, the tower wall is steel and has a circular cross section. The in-tower storage may be defined by first and second end caps welded to the inner surface of the tower wall or by an end cap near the top of the tower and by a sealing element attached to the tower wall adjacent the foundation, with the sealing element abutting the foundation.

  4. 76 FR 36983 - Marking Meteorological Evaluation Towers


    ... terrain. Without a similar evaluation process, the FAA cannot recommend lighting for METs. It is important... Federal Aviation Administration 14 CFR Part 77 Marking Meteorological Evaluation Towers AGENCY: Federal... recommended guidance for the voluntary marking of Meteorological Evaluation Towers (METs) erected in...

  5. Atmospheric Extenction in Solar Tower Plants


    Atmospheric attenuation of solar energy between heliostat and receiver in a solar tower plant can vary strongly with site and time - How strong can this loss be? - Which instruments can be used to measure this loss? - How can one connect accessible meteorological parameters with this loss? - Influence on output and design of Tower plants

  6. Fire ants perpetually rebuild sinking towers

    Phonekeo, Sulisay; Mlot, Nathan; Monaenkova, Daria; Hu, David L.; Tovey, Craig


    In the aftermath of a flood, fire ants, Solenopsis invicta, cluster into temporary encampments. The encampments can contain hundreds of thousands of ants and reach over 30 ants high. How do ants build such tall structures without being crushed? In this combined experimental and theoretical study, we investigate the shape and rate of construction of ant towers around a central support. The towers are bell shaped, consistent with towers of constant strength such as the Eiffel tower, where each element bears an equal load. However, unlike the Eiffel tower, the ant tower is built through a process of trial and error, whereby failed portions avalanche until the final shape emerges. High-speed and novel X-ray videography reveal that the tower constantly sinks and is rebuilt, reminiscent of large multicellular systems such as human skin. We combine the behavioural rules that produce rafts on water with measurements of adhesion and attachment strength to model the rate of growth of the tower. The model correctly predicts that the growth rate decreases as the support diameter increases. This work may inspire the design of synthetic swarms capable of building in vertical layers.

  7. Evaluation of the performance of the systems cooling auxiliary of the Almaraz NPP turbine building; Evaluacion del rendimiento de los sistemas de refrigeracion auxiliar del edificio de turbinas de CNA

    Vilar Carmona, G.


    After the successive performance improvements, to evacuate the thermal loads, and maintain acceptable temperatures throughout the year, added an auxiliary cooling system of the building of turbine, TCA system, composed of 5 shot forced by unit cooling towers.

  8. Danish Cool

    Toft, Anne Elisabeth


    Danish Cool. Keld Helmer-Petersen, Photography and the Photobook Handout exhibition text in English and Chinese by Anne Elisabeth Toft, Curator The exhibition Danish Cool. Keld Helmer-Petersen, Photography and the Photobook presents the ground-breaking work of late Danish photographer Keld Helmer...

  9. Carbon Nanotube Tower-Based Supercapacitor

    Meyyappan, Meyya (Inventor)


    A supercapacitor system, including (i) first and second, spaced apart planar collectors, (ii) first and second arrays of multi-wall carbon nanotube (MWCNT) towers or single wall carbon nanotube (SWCNT) towers, serving as electrodes, that extend between the first and second collectors where the nanotube towers are grown directly on the collector surfaces without deposition of a catalyst and without deposition of a binder material on the collector surfaces, and (iii) a porous separator module having a transverse area that is substantially the same as the transverse area of at least one electrode, where (iv) at least one nanotube tower is functionalized to permit or encourage the tower to behave as a hydrophilic structure, with increased surface wettability.

  10. Flux Sampling Errors for Aircraft and Towers

    Mahrt, Larry


    Various errors and influences leading to differences between tower- and aircraft-measured fluxes are surveyed. This survey is motivated by reports in the literature that aircraft fluxes are sometimes smaller than tower-measured fluxes. Both tower and aircraft flux errors are larger with surface heterogeneity due to several independent effects. Surface heterogeneity may cause tower flux errors to increase with decreasing wind speed. Techniques to assess flux sampling error are reviewed. Such error estimates suffer various degrees of inapplicability in real geophysical time series due to nonstationarity of tower time series (or inhomogeneity of aircraft data). A new measure for nonstationarity is developed that eliminates assumptions on the form of the nonstationarity inherent in previous methods. When this nonstationarity measure becomes large, the surface energy imbalance increases sharply. Finally, strategies for obtaining adequate flux sampling using repeated aircraft passes and grid patterns are outlined.

  11. Optimal Environmental Performance of Water-cooled Chiller System with All Variable Speed Configurations

    Yu, Fu Wing; Chan, Kwok Tai

    This study investigates how the environmental performance of water-cooled chiller systems can be optimized by applying load-based speed control to all the system components. New chiller and cooling tower models were developed using a transient systems simulation program called TRNSYS 15 in order to assess the electricity and water consumption of a chiller plant operating for a building cooling load profile. The chiller model was calibrated using manufacturer's performance data and used to analyze the coefficient of performance when the design and control of chiller components are changed. The NTU-effectiveness approach was used for the cooling tower model to consider the heat transfer effectiveness at various air-to-water flow ratios and to identify the makeup water rate. Applying load-based speed control to the cooling tower fans and pumps could save an annual plant operating cost by around 15% relative to an equivalent system with constant speed configurations.

  12. Augmented Reality Tower Technology Assessment

    Reisman, Ronald J.; Brown, David M.


    Augmented Reality technology may help improve Air Traffic Control Tower efficiency and safety during low-visibility conditions. This paper presents the assessments of five off-duty controllers who shadow-controlled' with an augmented reality prototype in their own facility. Initial studies indicated unanimous agreement that this technology is potentially beneficial, though the prototype used in the study was not adequate for operational use. Some controllers agreed that augmented reality technology improved situational awareness, had potential to benefit clearance, control, and coordination tasks and duties and could be very useful for acquiring aircraft and weather information, particularly aircraft location, heading, and identification. The strongest objections to the prototype used in this study were directed at aircraft registration errors, unacceptable optical transparency, insufficient display performance in sunlight, inadequate representation of the static environment and insufficient symbology.

  13. Application of Heat Pump in Cooling Water System of HIRFL


    Accelerator generates a lot of heat when it is working.It must be cooled by the circulating cooling water.Generally the heat was released to atimosphere by the cooling water tower.Because the heat energy is very huge(about 2M watts for HIRFL),it is big waste and the machine can’t be cooled to appropriate temperature when ambient temperature is high in summer.In order to solve the problems,the heat pump has been used

  14. Blasting response of the Eiffel Tower

    Horlyck, Lachlan; Hayes, Kieran; Caetano, Ryan; Tahmasebinia, Faham; Ansourian, Peter; Alonso-Marroquin, Fernando


    A finite element model of the Eiffel Tower was constructed using Strand7 software. The model replicates the existing tower, with dimensions justified through the use of original design drawings. A static and dynamic analysis was conducted to determine the actions of the tower under permanent, imposed and wind loadings, as well as under blast pressure loads and earthquake loads due to an explosion. It was observed that the tower utilises the full axial capacity of individual members by acting as a `truss of trusses'. As such, permanent and imposed loads are efficiently transferred to the primary columns through compression, while wind loads induce tensile forces in the windward legs and compressive forces in the leeward. Under blast loading, the tower experienced both ground vibrations and blast pressures. Ground vibrations induced a negligibly small earthquake loading into the structure which was ignored in subsequent analyses. The blast pressure was significant, and a dynamic analysis of this revealed that further research is required into the damping qualities of the structure due to soil and mechanical properties. In the worst case scenario, the blast was assumed to completely destroy several members in the adjacent leg. Despite this weakened condition, it was observed that the tower would still be able to sustain static loads, at least for enough time for occupant evacuation. Further, an optimised design revealed the structure was structurally sound under a 46% reduction of the metal tower's mass.

  15. Airborne LIDAR point cloud tower inclination judgment

    liang, Chen; zhengjun, Liu; jianguo, Qian


    Inclined transmission line towers for the safe operation of the line caused a great threat, how to effectively, quickly and accurately perform inclined judgment tower of power supply company safety and security of supply has played a key role. In recent years, with the development of unmanned aerial vehicles, unmanned aerial vehicles equipped with a laser scanner, GPS, inertial navigation is one of the high-precision 3D Remote Sensing System in the electricity sector more and more. By airborne radar scan point cloud to visually show the whole picture of the three-dimensional spatial information of the power line corridors, such as the line facilities and equipment, terrain and trees. Currently, LIDAR point cloud research in the field has not yet formed an algorithm to determine tower inclination, the paper through the existing power line corridor on the tower base extraction, through their own tower shape characteristic analysis, a vertical stratification the method of combining convex hull algorithm for point cloud tower scarce two cases using two different methods for the tower was Inclined to judge, and the results with high reliability.

  16. Tall Tower Wind Energy Monitoring and Numerical Model Validation in Northern Nevada

    Koracin, D. [Desert Research Inst. (DRI), Las Vegas, NV (United States); Kaplan, M. [Desert Research Inst. (DRI), Las Vegas, NV (United States); Smith, C. [Desert Research Inst. (DRI), Las Vegas, NV (United States); McCurdy, G. [Desert Research Inst. (DRI), Las Vegas, NV (United States); Wolf, A. [Desert Research Inst. (DRI), Las Vegas, NV (United States); McCord, T. [Desert Research Inst. (DRI), Las Vegas, NV (United States); King, K. [Desert Research Inst. (DRI), Las Vegas, NV (United States); Belu, R. [Drexel Univ., Philadelphia, PA (United States); Horvath, K. [Croatian Meteorological and Hydrological Service, Zagreb (Croatia)


    The main objectives of this project were to conduct a tall-tower and sodar field campaign in complex terrain, investigate wind properties relevant to wind energy assessment, and evaluate high-resolution models with fixed and adaptive grid structures. Two 60-m towers at Virginia Peak ridges near Washoe Valley, Nevada, were instrumented with cup and vane anemometers as well as sonic anemometers, and an acoustic sounder (hereafter sodar) was installed near one of the towers. The towers were located 2,700 m apart with a vertical distance of 140 m elevation between their bases. Each tower had a downhill exposure of rolling complex terrain, with the nearby valley floor 3,200 m to the west and 800 m below the summit. Cup anemometers were installed at both towers at 20, 40, and 60 m, wind vanes at 20 and 60 m, and sonic anemometers at 20 and 60 m. The sodar measurements were nominally provided every 10 m in vertical distance from 40 to 200 m with the quality of the data generally decreasing with height. Surface air temperature, atmospheric pressure, and radiation measurements were conducted at 1.5 m AGL at both of the towers. Although the plan was to conduct a 1-year period of data collection, we extended the period (October 5, 2012 through February 24, 2014) to cover for possible data loss from instrument or communication problems. We also present a preliminary analysis of the towers and sodar data, including a detailed inventory of available and missing data as well as outliers. The analysis additionally includes calculation of the Weibull parameters, turbulence intensity, and initial computation of wind power density at various heights.

  17. Implementation of gas district cooling and cogeneration systems in Malaysia; Mise en oeuvre de systemes de gas district cooling et de cogeneration en Malaisie

    Haron, S. [Gas District Cooling, M, Sdn Bhd (Malaysia)


    With its energy demand in the early 1990's growing at a high rate due to the country's strong economic growth, Malaysia studied various options to improve the efficiency of its energy use. Since its natural gas reserves are almost four times that of its crude oil reserves, efforts were therefore centered on seeking ways to boost the use of natural gas to mitigate the growing domestic energy need. PETRONAS, the national oil company, subsequently studied and chose the District Cooling System using natural gas as the primary source of fuel. The Kuala Lumpur City Center development, which houses the PETRONAS Twin Towers, was subsequently chosen as the first project to use the Gas District Cooling (GDC) System. To acquire the technology and implement this project, PETRONAS created a new subsidiary, Gas District Cooling (Malaysia) Sendirian Berhad (GDC(M)). In the process of improving the plant's efficiency, GDC(M) discovered that the GDC system's efficiency and project economics would be significantly enhanced if its is coupled to a Cogeneration system. Having proven the success of the GDC/Cogeneration system, GDC(M) embarked on a campaign to aggressively promote and seek new opportunities to implement the system, both in Malaysia-and abroad. Apart from enhancing efficiency of energy use, and providing better project economics, the GDC/Cogeneration system also is environment friendly. Today, the GDC/Cogeneration systems is the system of choice for several important developments in Malaysia, which also includes the country's prestigious projects such as the Kuala Lumpur International Airport and the New Federal Government Administrative Center in Putrajaya. (author)

  18. Numerical Analysis of the Safety Performance of the Intake Tower of Water Conservancy Project%肯斯瓦特水电站进水塔安全性能数值研究

    贺万莹; 郭德发


    This article had carried on the three-dimensional finite element analysis for the intake tower of Kenswat water conservancy engineering. The stress distribution during the periods of completion,construction and normal operation was calculated. Besides,the explicit and implicit meth-ods of dynamic calculation were applied to investigate the dynamic response of intake tower. The results show that in the static condition,stress near the gate slot is larger in the condition that access door is closed,the corresponding measures should be taken to reduce stress;explicit analysis found that the top acceleration is bigger than the ground acceleration,and the stress value is greatly raised,which may cause damage to buildings;Spectral analysis has a clear physical meaning with intuitive,and the calculation amount is much smaller,which is suitable for use in general engi-neering design.%对肯斯瓦特水电站进水塔进行了三维有限元计算分析,计算了结构在完建期、正常运行期以及检修期静力工况下的应力分布情况。因其地处8度地震区,故综合采用显式与隐式动力学方法计算考察了进水塔的动力响应。结果表明:静力工况中发现检修门关闭时,门槽附近的应力较大,应采取相应措施减小应力;瞬态分析发现塔顶部加速度比地面加速度要大,且应力值有较大幅度提高,可能导致建筑物损伤;谱分析的物理意义直观明确,且计算量较小,适合一般工程设计时使用。

  19. Wind towers architecture, climate and sustainability

    Bahadori, Mehdi N; Sayigh, Ali


    This book offers a holistic treatment of wind towers, from their underlying scientific principles to design and operation. Includes suggestions for optimization based on the authors' own research findings from recent analytical studies.

  20. Critical point wetting drop tower experiment

    Kaukler, W. F.; Tcherneshoff, L. M.; Straits, S. R.


    Preliminary results for the Critical Point Wetting CPW Drop Tower Experiment are produced with immiscible systems. Much of the observed phenomena conformed to the anticipated behavior. More drops will be needed to test the CPW theory with these immiscible systems.

  1. An Optimal Unramified Tower of Function Fields

    Brander, Kristian


    Efficient construction of long algebraic geometric--codes resulting from optimal towers of function fields is known to be difficult. In the following a tower which is both optimal and unramified after its third level, is investigated in the hope that its simple ramification structure can be explo...... be exploited in the construction of algebraic geometric--codes. Results are mostly negative, but help clarifying the difficulties in computing bases of Riemann--Roch spaces....

  2. Dubai Tower%迪拜高塔


    @@ The design for RMJM 83-storey Dubai Tower is a dynamic and elegantly proportioned skyscraper, rising over 400 metres above the Arabian Gulf. Situated at the prominent water' s edge, this crystalline glass tower is intended to provide an iconic and symbolic reference for Dubai in the neighbouring city of Doha, Qatar. The development will contain world-class retail, offices,hotel, serviced apartments and residential units.

  3. Control tower to surgical theater

    Buccioli Matteo


    Full Text Available The main social priority is to reduce public debt and to streamline national health service (NHS costs. Consequently, health managers need to acquire operating methods within their managerial structures so that all available resources are better planned in terms of effectiveness and efficiency, without compromising patient safety. In order to identify the information categories needed to know the whole surgical process is necessary to divide these in two main categories, supply and demand. Demand Information Group (DIG contains the information that identify patients and its needs in terms of care. Instead Supply Information Group (SIG contains information about hospital resources in order to cover the supply. The surgical process analyzed in terms such as industrial production process has the goal of produce the “health product for the patient” and its central part is performed in the operating room by a surgical team. This does not mean that the precedent and subsequent phases of the operating room have minor importance, in fact to obtain a high quality “health product” and reduce to a minimum the clinical risks related to the patient it is necessary that each phase of the process is carried out in the right way. The implementation of a Control Tower Approach allows for the management of productive process, able to guide hospital managers to identify the best strategies and to improve the risk management of patient safety in response to the guidelines of the World Health Organization.

  4. Use of Oriented Spray Nozzles to Set the Vapor-Air Flow in Rotary Motion in the Superspray Space of the Evaporative Chimney-Type Tower

    Dobrego, K. V.; Davydenko, V. F.; Koznacheev, I. A.


    The present paper considers the problem of upgrading the thermal efficiency of chimney-type evaporative cooling towers due to the rotary motion of the vapor-air flow in the superspray space. To set the vapor-air flow in rotary motion, we propose to use the momentum of the sprayed water. It has been shown that the existing parameters of spray nozzles permit setting up to 30% of the water flow momentum in translatory motion, which is enough for changing considerably the aerodynamics of the vapor-air flow in the superspray space and improving the operation of the cooling tower. The optimal angle of axial inclination of the spray cone has been estimated. Recommendations are given and problems have been posed for engineering realization of the proposed technologies in a chimney-type cooling tower.

  5. Sandia National Laboratories, Tonopah Test Range Askania Tower (Building 02-00): Photographs and Written Historical and Descriptive Data

    Ullrich, Rebecca A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Corporate Archives and History Program


    The Askania Tower (Building 02-00) was built in 1956 as part of the first wave of construction at the newly established Tonopah Test Range (TTR). Located at Station 2, near the primary target area at the range, the tower was one of the first four built to house Askania phototheodolites used in tracking test units dropped from aircraft. This report includes historical information, architectural information, sources of information, project information, maps, blueprints, and photographs.

  6. Ventilative Cooling

    Heiselberg, Per Kvols; Kolokotroni, Maria

    This report, by venticool, summarises the outcome of the work of the initial working phase of IEA ECB Annex 62 Ventilative Cooling and is based on the findings in the participating countries. It presents a summary of the first official Annex 62 report that describes the state-of-the-art of ventil......This report, by venticool, summarises the outcome of the work of the initial working phase of IEA ECB Annex 62 Ventilative Cooling and is based on the findings in the participating countries. It presents a summary of the first official Annex 62 report that describes the state...

  7. Public Safety Transmitter Towers, Public safety towers controlled by the FCC and combined with all other types of towers., Published in 2006, Johnson County AIMS.

    NSGIC GIS Inventory (aka Ramona) — This Public Safety Transmitter Towers dataset, was produced all or in part from Other information as of 2006. It is described as 'Public safety towers controlled by...

  8. Cellular Phone Towers - TOWERS_CELLUAR_FCC_ULS_IN: Cellular Towers in Indiana (Bernardin, Lochmueller & Associates, Derived from FCC ULS, Point Shapefile)

    NSGIC GIS Inventory (aka Ramona) — This dataset is a point shapefile of licensed cellular towers downloaded as part of the FCC ULS database of cellular towers in Indiana. The ground condition of this...

  9. PLANT TREES DONATE LOVE——SCITECH Tower & Place Participates in "Green Education Support"

    Bai Yifeng


    @@ On April 14, 2007, SCITECH Tower & Place organized over 70 tenants and employees to participate in the activity of "Planting trees and green education support", a part of the Green territory Project that was sponsored by China Environmental Education Fund in the environment education base in Dashiwo town, Fangshan District, Beijing.

  10. Tower Based Load Measurements for Individual Pitch Control and Tower Damping of Wind Turbines

    Kumar, A. A.; Hugues-Salas, O.; Savini, B.; Keogh, W.


    The cost of IPC has hindered adoption outside of Europe despite significant loading advantages for large wind turbines. In this work we presented a method for applying individual pitch control (including for higher-harmonics) using tower-top strain gauge feedback instead of blade-root strain gauge feedback. Tower-top strain gauges offer hardware savings of approximately 50% in addition to the possibility of easier access for maintenance and installation and requiring a less specialised skill-set than that required for applying strain gauges to composite blade roots. A further advantage is the possibility of using the same tower-top sensor array for tower damping control. This method is made possible by including a second order IPC loop in addition to the tower damping loop to reduce the typically dominating 3P content in tower-top load measurements. High-fidelity Bladed simulations show that the resulting turbine spectral characteristics from tower-top feedback IPC and from the combination of tower-top IPC and damping loops largely match those of blade-root feedback IPC and nacelle- velocity feedback damping. Lifetime weighted fatigue analysis shows that the methods allows load reductions within 2.5% of traditional methods.

  11. Adiabatic Rearrangement of Hollow PV Towers

    Eric A Hendricks


    Full Text Available Diabatic heating from deep moist convection in the hurricane eyewall produces a towering annular structure of elevated potential vorticity (PV. This structure has been referred to as a hollow PV tower. The sign reversal of the radial gradient of PV satisfies the Charney-Stern necessary condition for combined barotropic-baroclinic instability. For thin enough annular structures, small perturbations grow exponentially, extract energy from the mean flow, and lead to hollow tower breakdown, with significant vortex structural and intensity change. The three-dimensional adiabatic rearrangements of two prototypical hurricane-like hollow PV towers (one thick and one thin are examined in an idealized framework. For both hollow towers, dynamic instability causes air parcels with high PV to be mixed into the eye preferentially at lower levels, where unstable PV wave growth rates are the largest. Little or no mixing is found to occur at upper levels. The mixing at lower and middle levels is most rapid for the breakdown of the thin hollow tower, consistent with previous barotropic results. For both hollow towers, this advective rearrangement of PV affects the tropical cyclone structure and intensity in a number of ways. First, the minimum central pressure and maximum azimuthal mean velocity simultaneously decrease, consistent with previous barotropic results. Secondly, isosurfaces of absolute angular momentum preferentially shift inward at low levels, implying an adiabatic mechanism by which hurricane eyewall tilt can form. Thirdly, a PV bridge, similar to that previously found in full-physics hurricane simulations, develops as a result of mixing at the isentropic levels where unstable PV waves grow most rapidly. Finally, the balanced mass field resulting from the PV rearrangement is warmer in the eye between 900 and 700 hPa. The location of this warming is consistent with observed warm anomalies in the eye, indicating that in certain instances the hurricane

  12. Stochastic cooling

    Bisognano, J.; Leemann, C.


    Stochastic cooling is the damping of betatron oscillations and momentum spread of a particle beam by a feedback system. In its simplest form, a pickup electrode detects the transverse positions or momenta of particles in a storage ring, and the signal produced is amplified and applied downstream to a kicker. The time delay of the cable and electronics is designed to match the transit time of particles along the arc of the storage ring between the pickup and kicker so that an individual particle receives the amplified version of the signal it produced at the pick-up. If there were only a single particle in the ring, it is obvious that betatron oscillations and momentum offset could be damped. However, in addition to its own signal, a particle receives signals from other beam particles. In the limit of an infinite number of particles, no damping could be achieved; we have Liouville's theorem with constant density of the phase space fluid. For a finite, albeit large number of particles, there remains a residue of the single particle damping which is of practical use in accumulating low phase space density beams of particles such as antiprotons. It was the realization of this fact that led to the invention of stochastic cooling by S. van der Meer in 1968. Since its conception, stochastic cooling has been the subject of much theoretical and experimental work. The earliest experiments were performed at the ISR in 1974, with the subsequent ICE studies firmly establishing the stochastic cooling technique. This work directly led to the design and construction of the Antiproton Accumulator at CERN and the beginnings of p anti p colliding beam physics at the SPS. Experiments in stochastic cooling have been performed at Fermilab in collaboration with LBL, and a design is currently under development for a anti p accumulator for the Tevatron.

  13. Aerodynamical errors on tower mounted wind speed measurements due to the presence of the tower

    Bergstroem, H. [Uppsala Univ. (Sweden). Dept. of Meteorology; Dahlberg, J.Aa. [Aeronautical Research Inst. of Sweden, Bromma (Sweden)


    Field measurements of wind speed from two lattice towers showed large differences for wind directions where the anemometers of both towers should be unaffected by any upstream obstacle. The wind speed was measured by cup anemometers mounted on booms along the side of the tower. A simple wind tunnel test indicates that the boom, for the studied conditions, could cause minor flow disturbances. A theoretical study, by means of simple 2D flow modelling of the flow around the mast, demonstrates that the tower itself could cause large wind flow disturbances. A theoretical study, based on simple treatment of the physics of motion of a cup anemometer, demonstrates that a cup anemometer is sensitive to velocity gradients across the cups and responds clearly to velocity gradients in the vicinity of the tower. Comparison of the results from the theoretical study and field tests show promising agreement. 2 refs, 8 figs

  14. Wind-induced vibration control of long-span power transmission towers

    YIN Peng; LI Li; HU Liang-xia


    We investigated wind-induced vibration control of long-span power transmission towers based on a case study of the Jingdongnan-Nanyang-Jingmen 1000 kV transmission line project in P. R. China. The height of the cup tower is 181 m with a ground elevation of 47 m, which makes it a super flexible and wind-sensitive structure. Therefore, we should analyze the wind-resistant capacity of the system. We simulated applicable transverse fluctuating wind velocity field, developed a lead-rubber damper (LRD) for controlling wind-induced vibration of long-span transmission towers, deduced LRD calculation model parameter, and researched the best layout scheme and installation method of LRD. To calculate the wind-induced response of tower-line coupling system in seven layout schemes, we used the time history analysis method, and obtained the efficiencies of wind-induced vibration control. LRD deformation research proved that the damp of all LRDs was efficient under the designed wind velocity when they were laid along the edge of tower heads. We studied the controlling efficiency resulting from only applying stiffness to the tower poles where the dampers used to be laid under the designed wind velocity. The results show that the controlling efficiency was not ideal when the stiffness is increased on the poles only. Therefore, LRD should contribute to both the stiffness and damp of a structure to effectively reduce the dynamic response of a tower-line coupling system under strong winds. We also discussed the controlling efficiency of LRD under static winds. The results show that there was little difference between displacements derived by the finite element time history method and those obtained by static wind method conducted by a design institute. This means the simulation on space relevant wind velocity field was accurate and reasonable.

  15. The Drop Tower Bremen -An Overview

    von Kampen, Peter; Könemann, Thorben; Rath, Hans J.

    The Center of Applied Space Technology and Microgravity (ZARM) was founded in 1985 as an institute of the University of Bremen, which focuses on research on gravitational and space-related phenomena. In 1988, the construction of ZARM`s drop tower began. Since its inau-guration in September 1990, the eye-catching Drop Tower Bremen with a height of 146m and its characteristic glass roof has become twice a landmark on the campus of the University of Bremen and the emblem of the technology park Bremen. As such an outstanding symbol of space science in Bremen the drop tower provides an european unique facility for experiments under conditions of high-quality weightlessness with residual gravitational accelerations in the microgravity regime. The period of maximum 4.74s of each freely falling experiment at the Drop Tower Bremen is only limited by the height of the drop tower vacuum tube, which was fully manufactured of steal and enclosed by an outer concrete shell. Thus, the pure free fall height of each microgravity drop experiment is approximately 110m. By using the later in-stalled catapult system established in 2004 ZARM`s short-term microgravity laboratory is able to nearly double the time of free fall. This world-wide inimitable capsule catapult system meets scientists` demand of extending the period of weightlessness. During the catapult operation the experiment capsule performs a vertical parabolic flight within the drop tower vacuum tube. In this way the time of microgravity can be extended to slightly over 9s. Either in the drop or in the catapult operation routine the repetition rates of microgravity experiments at ZARM`s drop tower facility are the same, generally up to 3 times per day. In comparison to orbital platforms the ground-based laboratory Drop Tower Bremen represents an economic alternative with a permanent access to weightlessness on earth. Moreover, the exceptional high quality of weightlessness in order of 1e-6 g (in the frequency range below 100

  16. Smart energy option: Reusing wastewater for cooling energy

    Clapham, A. [Boeing Co., Seattle, WA (United States); Jackman, J. [Puget Sound Power and Light Co., Bellevue, WA (United States); Lundt, M.M. [King County Department of Metropolitan Services, Seattle, WA (United States). Water Pollution Control Dept.


    The King County Department of Metropolitan Services, an airplane manufacturer, and a Seattle utility are ready to begin operating the first commercial effluent-based cooling system for buildings in the Northwest. This paper details the studies undertaken to design the system and how the manufacturer addressed its employees` concerns about a new system. There are several environmental benefits to using effluent as a cooling medium. Considerable energy savings in chiller operations are achieved because the effluent temperature is 10 to 20 degrees cooler than water returned from cooling towers. Another major benefit is water conservation. Conventional cooling towers would consume several million gallons of water each year. By using effluent, the consumption of this water will be avoided. Water run through cooling towers is treated with chemicals to prevent corrosion and biological growth. With the effluent in a closed-loop system, there will be no need to treat the effluent. Consequently there will be a reduction in use of water treatment chemicals that are ultimately discharged into the sewer system. This reduces the treatment load to the county and helps to maintain a cleaner environment. The concept is simple: recover heat wasted from one activity for reuse in another. The delivery is easy: send effluent via a pipeline to customer`s chillers to pick up heat and return that heat to the plant. The selling of this idea is the focus of this paper.

  17. L’avant-corps de la tour philippienne du château de Chinon (Indre-et-Loire : un exemple d’adaptation d’un standard architectural aux contraintes topographiques The projecting part of a Philippe Auguste tower in the stronghold of Chinon (Indre-et-Loire: an example of the adaption of an architectural standard to topographic constraints

    Bastien Lefebvre


    Full Text Available Le “ donjon du Coudray ” est une tour circulaire de type philippien dont le donjon n’est pas entièrement classique, puisque, contrairement aux autres érigés par les ingénieurs de Philippe Auguste, elle est desservie par un avant-corps rectangulaire donnant accès au premier étage. Sa fouille et l’étude fine de ses élévations ont permis de s’assurer que cet avant-corps atypique était bien contemporain de la tour. On a pu en reconstituer avec certitude les parties disparues. Plus qu’un archaïsme contredit par le soin apporté à l’édifice tout entier, les auteurs l’interprètent comme une réponse ponctuelle à une contrainte topographique.The Coudray keep is a circular tower of the Philippe Auguste type. The tower type is not entirely classic, since, as opposed to others erected by the engineers of Philippe Auguste, it is served by a rectangular projection which gives access to the first floor. The excavation and detailed study of its elevations have enabled us to ensure that the unusual projection was really comptemporary with the tower. It was possible to reconstruct its missing sections with certainty. More than just an archaism contradicted by the care given to the building as a whole, the creators construed it as a short term answer to a topographic constraint.

  18. Tilts of the Master Equatorial Tower

    Ahlstrom, H. G., Jr.; Gawronski, W.; Girdner, D.; Noskoff, E.; Sommerville, J. N.


    At the center of the DSS-14 antenna, a tower reaches to the focal point of the antenna dish. The master equatorial (ME) instrument is located at the top of the tower. This instrument precisely (with an accuracy that exceeds that of the antenna) follows the commanded trajectory. Through the optical coupling, the antenna focal point follows the ME. One factor of the antenna pointing precision is the movement of the ME base, i.e., the top of the tower. For this reason, measurements of the ME tower tilts have been taken in order to quantify the tilts, to determine possible causes of the tilting, and to update the antenna pointing budget. They were conducted under three antenna operating modes: during tracking, slewing, and antenna stowing. The measurements indicate that the ME tower tilts introduce significant pointing errors that exceed the required 32-GHz (Ka-band) pointing precision (estimated as 0.8 mdeg for a 0.1-dB gain loss). Four different sources of tilt were identified and require verification.

  19. A very cool cooling system

    Antonella Del Rosso


    The NA62 Gigatracker is a jewel of technology: its sensor, which delivers the time of the crossing particles with a precision of less than 200 picoseconds (better than similar LHC detectors), has a cooling system that might become the precursor to a completely new detector technique.   The 115 metre long vacuum tank of the NA62 experiment. The NA62 Gigatracker (GTK) is composed of a set of three innovative silicon pixel detectors, whose job is to measure the arrival time and the position of the incoming beam particles. Installed in the heart of the NA62 detector, the silicon sensors are cooled down (to about -20 degrees Celsius) by a microfluidic silicon device. “The cooling system is needed to remove the heat produced by the readout chips the silicon sensor is bonded to,” explains Alessandro Mapelli, microsystems engineer working in the Physics department. “For the NA62 Gigatracker we have designed a cooling plate on top of which both the silicon sensor and the...

  20. Simulation of an absorption based solar cooling facility using a geothermal sink for heat rejection

    Salgado, Rafael; Burguete, Ana; Rodríguez, María del Carmen; Rodríguez, Pedro


    An important issue of solar cooling facilities based on absorption cycles and sometimes not given the necessary attention is the recooling process of the absorber and condenser. This is critical in the overall behaviour of the facility because the condensation and absorption temperatures will affect the COP and cooling capacity of the chiller. Most of the time the recooling process is made by using a wet cooling tower in a closed loop through the absorber and condenser. The use of a wet cooli...

  1. The possible use of ancient tower tombs as watchtowers in Syro-Mesopotamia

    Silver, M.; Törmä, M.; Silver, K.; Okkonen, J.; Nuñez, M.


    Traditionally polygonal tower tombs dating from the Greco-Roman era, especially found in the area of Syro-Mesopotamia, have only been treated as funerary structures without discussion of their other possible purposes. In this paper we wish to inquire whether they had other functions as well. The most famous examples of these types of tombs are situated in Palmyra in Syria. They are built of limestone, follow a square layout, and some exceed the height of 20 m. Similar structures are found in the Euphrates valley of Syria. The Finnish project SYGIS that worked in the neighbourhood of the Euphrates and Palmyra during the previous decade studied some of the structures in the region. As far as the tower tombs are concerned, our research suggests that new structural, topographical and spatial aspects can be raised, and GIS (Geographic Information Systems) can be applied for analysing their properties for visibility. The tendency to locate tower tombs along roads and the entrance areas of a city as well as at a mountain edge seems to indicate that the tombs may have had observational functions serving as watch towers. The aspects of the location in terrains are emphasized in the present study, and digital terrain models were utilized using SRTM DEM (Digital Elevation Model) data for carrying out viewshed analyses in order to survey the observational qualities of the towers in Palmyra, on Halabiya, on Jebel Bishri in Syria and Hatra in Iraq.

  2. Cooling technique

    Salamon, Todd R; Vyas, Brijesh; Kota, Krishna; Simon, Elina


    An apparatus and a method are provided. Use is made of a wick structure configured to receive a liquid and generate vapor in when such wick structure is heated by heat transferred from heat sources to be cooled off. A vapor channel is provided configured to receive the vapor generated and direct said vapor away from the wick structure. In some embodiments, heat conductors are used to transfer the heat from the heat sources to the liquid in the wick structure.

  3. CFD simulation of a solar tower

    Koten, Hasan; Yukselenturk, Yalcyn; Yilmaz, Mustafa [Marmara University Mechanical Engineering Department (Turkey)], E-mail:


    With the depletion of fossil fuels and the rising concerns about their impacts on the environment, the use of alternative energy sources has become necessary. Among the alternatives, solar energy, with its unlimited resources and its low impact on the environment, is the most promising. The aim of this paper is to present a numerical model of a regular solar tower. A CFD analysis of the solar tower was performed with a commercial CFD code and velocity fields, temperature measurements and flow characteristics were determined and compared to experimental results available in the literature. It was found that the numerical model is capable of assessing the buoyant air flow in chimneys. In addition results showed that increasing the solar chimney height, solar collector area, or solar irradiance increases power generation capacity while ambient temperature does not significantly affect this capacity. This study provided a numerical model which is proficient in modeling solar towers.

  4. Installing met towers in marine environments

    Hanberg, Jackie [DNV Canada (Canada)


    Onshore measurements are taken to supplement offshore wind resource measurement campaigns. To maximize the quality of the measured data, the conditions presented by marine environments must be well understood and mitigated. This paper discusses the several factors that need attention prior to installation of the met towers. The towers experience high corrosion from their exposure to moist, salt-laden, marine air. Careful instrumentation and material selection can prevent or decrease corrosion. Stainless or galvanized hardware and coating sensor terminals with petroleum jelly are both helpful. Soil in the marine environment has variable moisture levels and is extremely wet, which makes grounding systems and backfill enhancers necessary. Weather conditions in these environments also tend to be unpredictable; hence, towers should be strong enough to handle typical marine weather. In conclusion, successful marine wind resource assessment campaigns require environmental research, careful planning, and awareness of the specific issues.

  5. Engineering photochemical smog through convection towers

    Elliott, S.; Prueitt, M.L.; Bossert, J.E.; Mroz, E.J.; Krakowski, R.A.; Miller, R.L. [Los Alamos National Lab., NM (United States); Jacobson, M.Z.; Turco, R.P. [Los Alamos National Lab., NM (United States)]|[Univ. of California, Los Angeles, CA (United States). Atmospheric Sciences Dept.


    Reverse convection towers have attracted attention as a medium for cleansing modern cities. Evaporation of an aqueous mist injected at the tower opening could generate electrical power by creating descent, and simultaneously scavenge unsightly and unhealthful particulates. The study offered here assesses the influence to tower water droplets on the photochemical component of Los Angeles type smog. The primary radical chain initiator OH is likely removed into aqueous phases well within the residence time of air in the tower, and then reacts away rapidly. Organics do not dissolve, but nighttime hydrolysis of N{sub 2}O{sub 5} depletes the nitrogen oxides. A lack of HOx would slow hydrocarbon oxidation and so also ozone production. Lowering of NOx would also alter ozone production rates, but the direction is uncertain. SO{sub 2} is available in sufficient quantities in some urban areas to react with stable oxidants, and if seawater were the source of the mist, the high pH would lead to fast sulfur oxidation kinetics. With an accommodation coefficient of 10{sup {minus}3}, however, ozone may not enter the aqueous phase efficiently. Even if ozone is destroyed or its production suppressed, photochemical recovery times are on the order of hours, so that tower processing must be centered on a narrow midday time window. The cost of building the number of structures necessary for this brief turnover could be prohibitive. The increase in humidity accompanying mist evaporation could be controlled with condensers, but might otherwise counteract visibility enhancements by recreating aqueous aerosols. Quantification of the divergent forcings convection towers must exert upon the cityscape would call for coupled three dimensional modeling of transport, microphysics, and photochemistry. 112 refs.

  6. Atmospheric extinction in simulation tools for solar tower plants

    Hanrieder, Natalie; Wilbert, Stefan; Schroedter-Homscheidt, Marion; Schnell, Franziska; Guevara, Diana Mancera; Buck, Reiner; Giuliano, Stefano; Pitz-Paal, Robert


    Atmospheric extinction causes significant radiation losses between the heliostat field and the receiver in a solar tower plants. These losses vary with site and time. State of the art is that in ray-tracing and plant optimization tools, atmospheric extinction is included by choosing between few constant standard atmospheric conditions. Even though some tools allow the consideration of site and time dependent extinction data, such data sets are nearly never available. This paper summarizes and compares the most common model equations implemented in several ray-tracing tools. There are already several methods developed and published to measure extinction on-site. An overview of the existing methods is also given here. Ray-tracing simulations of one exemplary tower plant at the Plataforma Solar de Almería (PSA) are presented to estimate the plant yield deviations between simulations using standard model equations instead of extinction time series. For PSA, the effect of atmospheric extinction accounts for losses between 1.6 and 7 %. This range is caused by considering overload dumping or not. Applying standard clear or hazy model equations instead of extinction time series lead to an underestimation of the annual plant yield at PSA. The discussion of the effect of extinction in tower plants has to include overload dumping. Situations in which overload dumping occurs are mostly connected to high radiation levels and low atmospheric extinction. Therefore it can be recommended that project developers should consider site and time dependent extinction data especially on hazy sites. A reduced uncertainty of the plant yield prediction can significantly reduce costs due to smaller risk margins for financing and EPCs. The generation of extinction data for several locations in form of representative yearly time series or geographical maps should be further elaborated.

  7. The new Drop Tower catapult system

    von Kampen, Peter; Kaczmarczik, Ulrich; Rath, Hans J.


    The Center of Applied Space Technology and Microgravity (ZARM) was founded in 1985 as an institute of the University Bremen, which focuses on research on gravitational and space-related phenomena. In 1988, the construction of the "Drop Tower" began. Since then, the eye-catching tower with a height of 146 m and its characteristic glass roof has become the emblem of the technology centre in Bremen. The Drop Tower Bremen provides a facility for experiments under conditions of weightlessness. Items are considered weightless, when they are in "free fall", i.e. moving without propulsion within the gravity field of the earth. The height of the tower limits the simple "free fall" experiment period to max. 4.74 s. With the inauguration of the catapult system in December 2004, the ZARM is entering a new dimension. This world novelty will meet scientists' demands of extending the experiment period up to 9.5 s. Since turning the first sod on May 3rd, 1988, the later installation of the catapult system has been taken into account by building the necessary chamber under the tower. The catapult system is located in a chamber 10 m below the base of the tower. This chamber is almost completely occupied by 12 huge pressure tanks. These tanks are placed around the elongation of the vacuum chamber of the drop tube. In its centre there is the pneumatic piston that accelerates the drop capsule by the pressure difference between the vacuum inside the drop tube and the pressure inside the tanks. The acceleration level is adjusted by means of a servo hydraulic breaking system controlling the piston velocity. After only a quarter of a second the drop capsule achieves its lift-off speed of 175 km/h. With this exact speed, the capsule will rise up to the top of the tower and afterwards fall down again into the deceleration unit which has been moved under the drop tube in the meantime. The scientific advantages of the doubled experiment time are obvious: during almost 10 s of high

  8. Towers and KM3NeT

    Anassontzis, E. G.; Aggouras, G.; Ball, A. E.; Chinowsky, W.; Fahrun, E.; Grammatikakis, G.; Green, C.; Grieder, P.; Katrivanos, P.; Koske, P.; Markopoulos, E.; Minkowsky, P.; Nygren, D.; Papageorgiou, K.; Przybylski, G.; Resvanis, L. K.; Siotis, I.; Sopher, J.; Tsagli, V.; Zhukov, V. A.


    NESTOR Collaboration has deployed one NESTOR module of the deep-sea neutrino telescope at a depth of 4000 m, 14 km off the southwest coast of Greece. The deployment site provides excellent environmental data. Power and data were transferred through a 30 km electro-optical cable to the shore laboratory. In this report, we describe briefly the detector and the well-defined procedure for recovery and deployment of a detector attached to the electro-optical cable and we depict the deployment of several towers and complementary independent strings acoustically connected to the towers.

  9. Flangeless Connections in Steel Tubular Wind Towers

    Heistermann, Christine; Tran, Anh Tuan; Veljkovic, Milan, ed. lit.; Rebelo, Carlos


    Extensive research is conducted on the improvement of renewable energies. One field is the use of wind energy, where the tower construction is one of the main issues. This paper deals with new ideas and ongoing research in this area. To raise the height of steel tubular towers, fatigue as the design limit and constraints due to transportation issues have to be overcome. Changes in the cross-section are considered as one of possible solutions. This work presents an extensive finite element stu...

  10. Dolmen and Tower Tombs (3600 - 2000 BC)

    Steimer-Herbet, Tara


    In the proto-historic period, the territory of contemporary Jordan was covered with megalithic tombs of two types that correspond to different livelihoods, associated with more or less arid environments. Thus, sedentary settlements developed dolmen necropolises, while the steppe was covered with tower tombs. Figure II.15 — Tower Tombs and Dolmens in Ancient Bronze Time. In Jordan, the construction of megalithic tombs began in the early 4th millennium BC and faded at the turn of the 2nd mille...

  11. Study on the Application of the Groundcover Plants in the Roof Greening:Setting Roof Greening Projects Surrounding the Yellow Crane Tower of Wuhan City as an Example%地被植物在屋顶绿化中的运用——以武汉市武昌区黄鹤楼周边屋顶绿化项目为例

    陈杰; 龚颖; 闫森


    城市的生态化是后工业时代对城市综合功能提出的必然要求,屋顶绿化的发展已成为趋势.园地制宜、有针对性地分选择绿化植物是屋顶绿化建设成败的关键.该文章结合黄鹤楼周边屋顶绿化工程,认为可以通过对地被植物的合理配置以及控制性的造景,使屋顶绿化获得理想的景观效果和生态效应.%The ecological development is an inevitable request of comprehensive urban function in the post-industrial era. The roof greening is becoming a trend of modern times. The application of the right plants according to the specific local conditions is crucial to the success of the green roof construction. Combined with the roof greening projects surrounding the Yellow Crane Tower, the article puts forward that the rational allocation of groundcover plants and the controlled landscaping can make both ideal landscape and ecological effects of the roof greening.

  12. Thermal Effect of the Cable-Stayed Bridge Tower

    Zhang Hai-long; Li Jun; Liu Chang-guo; Jiang Tian-hua; Wei jun


    This paper studies the thermal effect of the cable-stayed bridge tower based on full time accurate measurement and finite element analysis on Xiantao Hanjiang River Highway Bridge. The measured results and the displacement variation of top tower show that the tower rotates periodically when it is exposed in sunshine. But the tower column will not decline when there is no sunshine. In spite of in winter or in summer, the period when the tower column changed smallest is from 0∶00 am to 5∶00 am. The time period when the tower column has maximum deviation lags behind the time when the tower column has maximum temperature difference, and this phenomenon is obvious in winter. The conclusions also have directive value in predicting the tower deformations and their directions in construction control of cable-stayed bridge, and in verifying the finite element program.

  13. Low-cost Triangular Lattice Towers for Small Wind Turbines

    Adhikari, Ram Chandra

    This thesis focuses on the study of low-cost steel and bamboo triangular lattice towers for small wind turbines. The core objective is to determine the material properties of bamboo and assess the feasibility of bamboo towers. Using the experimentally determined buckling resistance, elastic modulus, and Poisson's ratio, a 12 m high triangular lattice tower for a 500W wind turbine has been modeled as a tripod to formulate the analytical solutions for the stresses and tower deflections, which enables design of the tower based on buckling strength of tower legs. The tripod formulation combines the imposed loads, the base distance between the legs and tower height, and cross-sectional dimensions of the tower legs. The tripod model was used as a reference for the initial design of the bamboo tower and extended to finite element analysis. A 12 m high steel lattice tower was also designed for the same turbine to serve as a comparison to the bamboo tower. The primary result of this work indicates that bamboo is a valid structural material. The commercial software package ANSYS APDL was used to carry out the tower analysis, evaluate the validity of the tripod model, and extend the analysis for the tower design. For this purpose, a 12 m high steel lattice tower for a 500 W wind turbine was examined. Comparison of finite element analysis and analytical solution has shown that tripod model can be accurately used in the design of lattice towers. The tower designs were based on the loads and safety requirements of international standard for small wind turbine safety, IEC 61400-2. For connecting the bamboo sections in the lattice tower, a steel-bamboo adhesive joint combined with conventional lashing has been proposed. Also, considering the low durability of bamboo, periodic replacement of tower members has been proposed. The result of this study has established that bamboo could be used to construct cost-effective and lightweight lattice towers for wind turbines of 500 Watt

  14. Third symposium: Solar cooling practice. Proceedings; Drittes Symposium: Solares Kuehlen in der Praxis. Tagungsband

    Jakob, U. (comp.)


    The hot summer of 2003, with more than three degrees higher average daily temperatures and about 20 percent higher insolation, increased the demand for environment-friendly cooling technologies. Thermal cooling with solar energy or waste heat will prevent extreme loads on the public grids. Large-scale projects like the Umweltamt Augsburg office building and an office tower in Kosovo have shown that solar cooling is practically feasible. New developments in liquid absorption are presented both by the producer and in a pilot project involving an Amberg office building. New technologies like diffusion-absorption refrigerators or high-performance two-stage absorption refrigerators were presented at the symposium as well. Attendants were planners, architects, engineers, scientists, and engineers working in air conditioning, solar and refrigeration engineering. The programme was complemented by a general introduction to the market and technology of thermal cooling and by economic efficiency analyses. [German] Nach dem Spitzensommer 2003 mit mehr als 3 Grad hoeheren mittleren Tagestemperaturen und knapp 20% mehr Einstrahlung stellt sich verstaerkt die Frage nach umweltfreundlichen Kuehltechnologien. Um die extreme Belastung der Stromnetze zu vermeiden, bieten sich thermische Kuehlverfahren an, die mit Solarenergie oder Abwaerme betrieben werden. Betriebserfahrungen mit erprobten Technologien in grossen Bauvorhaben wie im Umweltamt Augsburg oder in einem Buerotower im Kosovo zeigen, dass schon heute solares Kuehlen in der Praxis machbar ist. Neuentwicklungen in der Fluessigsorption werden sowohl vom Hersteller praesentiert als auch in einem grosstechnischen Pilotprojekt in einem Amberger Buerobau vorgestellt. Auch neue Technologien wie Diffusions-Absorptionskaeltemaschinen oder zweistufige Absorptionskaelteanlagen mit hohen Leistungszahlen duerfen bei dem Symposium nicht fehlen. Das Symposium richtet sich an Planer, Architekten, Ingenieure, Wissenschaftler und Ingenieure

  15. Water Cooled Mirror Design

    Dale, Gregory E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Holloway, Michael Andrew [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pulliam, Elias Noel [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)


    This design is intended to replace the current mirror setup being used for the NorthStar Moly 99 project in order to monitor the target coupon. The existing setup has limited movement for camera alignment and is difficult to align properly. This proposed conceptual design for a water cooled mirror will allow for greater thermal transfer between the mirror and the water block. It will also improve positioning of the mirror by using flexible vacuum hosing and a ball head joint capable of a wide range of motion. Incorporating this design into the target monitoring system will provide more efficient cooling of the mirror which will improve the amount of diffraction caused by the heating of the mirror. The process of aligning the mirror for accurate position will be greatly improved by increasing the range of motion by offering six degrees of freedom.

  16. ATLAS - Liquid Cooling Systems

    Bonneau, P.


    Photo 1 - Cooling Unit - Side View Photo 2 - Cooling Unit - Detail Manifolds Photo 3 - Cooling Unit - Rear View Photo 4 - Cooling Unit - Detail Pump, Heater and Exchanger Photo 5 - Cooling Unit - Detail Pump and Fridge Photo 6 - Cooling Unit - Front View

  17. Optimization of steel monopod offshore-towers under probabilistic constraints

    Vrouwenvelder, A.C.W.M.


    In this work, economical design implementation of a circular steel monopod-offshore-tower, which is subjected to the extreme wave loading, is presented. The mass of the tower is considered as the objective function. The thickness and radius of the cross-section of the tower are adopted as design var

  18. Balsa Tower Walls Brave "Big Buster"

    Granlund, George


    Like many technology teachers, the author, a technology education teacher at Arthur Hill High School in Saginaw, Michigan, tries to stretch his budget by "milking" each student activity for maximum benefit. In the technology department, they use balsa wood towers to teach the basics of structural engineering. To get the most from their materials,…

  19. FORIDA Towers - Analysis of steel transition piece

    Jensen, Lars Rom; Dollerup, Niels; Damkilde, Lars

    This report is a detailed analysis of the transition piece connecting the hybrid wind turbine towers lower UHPFRC part with the top steel part. The analysis of the transition piece includes a validation of the Service Limit State (SLS), the Ultimate Limit State (ULS) and the Fatigue loads. The an...

  20. Gravity Helped Terrorists Destory Twin Towers



    Though terrorists triggered (触发) the collapse (倒塌) of the World Trade Center's Twin Towers, much of the energy--calculated by a physicist to have been at least 2 percent that of the atomic bomb dropped on Hiroshima(广岛)--was supplied by nature's most ubiquitous(普通存在的)force: gravity.

  1. Tower Power: Producing Fuels from Solar Energy

    Antal, M. J., Jr.


    This article examines the use of power tower technologies for the production of synthetic fuels. This process overcomes the limitations of other processes by using a solar furnace to drive endothermic fuel producing reactions and the resulting fuels serve as a medium for storing solar energy. (BT)

  2. The Tower of Hanoi and Inductive Logic

    Merrotsy, Peter


    In the "Australian Curriculum," the concept of mathematical induction is first met in the senior secondary subject Specialist Mathematics. This article details an example, the Tower of Hanoi problem, which provides an enactive introduction to the inductive process before moving to more abstract and cognitively demanding representations.…

  3. Design considerations for concentrating solar power tower systems employing molten salt.

    Moore, Robert Charles; Siegel, Nathan Phillip; Kolb, Gregory J.; Vernon, Milton E.; Ho, Clifford Kuofei


    The Solar Two Project was a United States Department of Energy sponsored project operated from 1996 to 1999 to demonstrate the coupling of a solar power tower with a molten nitrate salt as a heat transfer media and for thermal storage. Over all, the Solar Two Project was very successful; however many operational challenges were encountered. In this work, the major problems encountered in operation of the Solar Two facility were evaluated and alternative technologies identified for use in a future solar power tower operating with a steam Rankine power cycle. Many of the major problems encountered can be addressed with new technologies that were not available a decade ago. These new technologies include better thermal insulation, analytical equipment, pumps and values specifically designed for molten nitrate salts, and gaskets resistant to thermal cycling and advanced equipment designs.

  4. Update on the Purdue University 2-second Drop Tower

    Collicott, Steven

    A small drop tower of approximately one second drop duration was built in the School of Aero-nautics and Astronautics at Purdue University beginning in 1998 and operated until summer 2007. This inexpensive tower in an old airplane hanger, was built largely by Yongkang Chen, now a Research Professor at Portland State University in Oregon, USA. In about 7 years of operations, the tower generated sufficient science results for Chen's PhD thesis[1] (summarized in three AIAA Journal papers[2-4]), Fitzpatrick's MS thesis[5], two industry projects for since-canceled advanced rodent habitats for ISS, and one project for NASA Marshall. In addition to the science use, Purdue undergraduate students designed, built, and performed simpler fluids experiments for their own career advancement, including a novel investigation of the impact of imperfect repeatability of initial conditions on a zero-g fluids experiment. The tower was also used for outreach to school children. It is most satisfying that Chen's PhD research in this small tower, and subsequent discussions and interactions, helped Weislogel to propose the two Vane Gap tests in his highly successful Capillary Fluids Experiment (CFE) in the International Space Station in 2006 and 2007[6]. Chen as been involved in the remodeling of these two Vane Gap cylinders for subsequent re-launch to ISS for a second round of experiments expected in 2010 and 2011. In August 2007 the School of Aeronautics and Astronautics at Purdue University moved into the new Neil Armstrong Hall of Engineering and construction on a new 2-second drop tower began. A vertical shaft of nearly 23 meters was designed into the building. An approximately 80 m2 general-use fluids lab is at the top level, and a small access room of approximately 9 m2 is at the bottom. However, construction of the new $57M building created only the space for the science facility, not the science facility itself. The science facility is under construction and this paper presents

  5. WRI 50: Strategies for Cooling Electric Generating Facilities Utilizing Mine Water

    Joseph J. Donovan; Brenden Duffy; Bruce R. Leavitt; James Stiles; Tamara Vandivort; Paul Ziemkiewicz


    Power generation and water consumption are inextricably linked. Because of this relationship DOE/NETL has funded a competitive research and development initiative to address this relationship. This report is part of that initiative and is in response to DOE/NETL solicitation DE-PS26-03NT41719-0. Thermal electric power generation requires large volumes of water to cool spent steam at the end of the turbine cycle. The required volumes are such that new plant siting is increasingly dependent on the availability of cooling circuit water. Even in the eastern U.S., large rivers such as the Monongahela may no longer be able to support additional, large power stations due to subscription of flow to existing plants, industrial, municipal and navigational requirements. Earlier studies conducted by West Virginia University (WV 132, WV 173 phase I, WV 173 Phase II, WV 173 Phase III, and WV 173 Phase IV in review) have identified that a large potential water resource resides in flooded, abandoned coal mines in the Pittsburgh Coal Basin, and likely elsewhere in the region and nation. This study evaluates the technical and economic potential of the Pittsburgh Coal Basin water source to supply new power plants with cooling water. Two approaches for supplying new power plants were evaluated. Type A employs mine water in conventional, evaporative cooling towers. Type B utilizes earth-coupled cooling with flooded underground mines as the principal heat sink for the power plant reject heat load. Existing mine discharges in the Pittsburgh Coal Basin were evaluated for flow and water quality. Based on this analysis, eight sites were identified where mine water could supply cooling water to a power plant. Three of these sites were employed for pre-engineering design and cost analysis of a Type A water supply system, including mine water collection, treatment, and delivery. This method was also applied to a ''base case'' river-source power plant, for comparison. Mine

  6. Marginal costs of water savings from cooling system retrofits: a case study for Texas power plants

    Loew, Aviva; Jaramillo, Paulina; Zhai, Haibo


    The water demands of power plant cooling systems may strain water supply and make power generation vulnerable to water scarcity. Cooling systems range in their rates of water use, capital investment, and annual costs. Using Texas as a case study, we examined the cost of retrofitting existing coal and natural gas combined-cycle (NGCC) power plants with alternative cooling systems, either wet recirculating towers or air-cooled condensers for dry cooling. We applied a power plant assessment tool to model existing power plants in terms of their key plant attributes and site-specific meteorological conditions and then estimated operation characteristics of retrofitted plants and retrofit costs. We determined the anticipated annual reductions in water withdrawals and the cost-per-gallon of water saved by retrofits in both deterministic and probabilistic forms. The results demonstrate that replacing once-through cooling at coal-fired power plants with wet recirculating towers has the lowest cost per reduced water withdrawals, on average. The average marginal cost of water withdrawal savings for dry-cooling retrofits at coal-fired plants is approximately 0.68 cents per gallon, while the marginal recirculating retrofit cost is 0.008 cents per gallon. For NGCC plants, the average marginal costs of water withdrawal savings for dry-cooling and recirculating towers are 1.78 and 0.037 cents per gallon, respectively.


    Dave Murnane; Renauld Washington


    This Topical Report is presented to satisfy reporting requirements in the Statement of work section J.5 page 120 per Department of Energy contract DE-AC26-01NT41093. The project does not contain any imperial research data. This report describes the assembly of Commercial off the shelf (COTS) items configured in a unique manner to represent new and innovative technology in the service of size reduction and material handling at DOE sites, to assist in the D&D effort currently underway at the designated DOE Facilities.



    Based on the analysis of air flow and heat transfer in the dry-cooling tower for Harmon system, a combined iteration method is presented to solve the coupled heat transfer and draft equations derived from theoretical and empirical formulas, with the size of the exchangers and the cooling tower or the systematic parameters being determined. Taking the 686 MW unit as an example, the present calculating results are well agreed with those of the real case, and thus the method presented is practical and feasible for reasonable design of Harmon system.

  9. Cool visitors


    Pictured, from left to right: Tim Izo (saxophone, flute, guitar), Bobby Grant (tour manager), George Pajon (guitar). What do the LHC and a world-famous hip-hop group have in common? They are cool! On Saturday, 1st July, before their appearance at the Montreux Jazz Festival, three members of the 'Black Eyed Peas' came on a surprise visit to CERN, inspired by Dan Brown's Angels and Demons. At short notice, Connie Potter (Head of the ATLAS secretariat) organized a guided tour of ATLAS and the AD 'antimatter factory'. Still curious, lead vocalist Will.I.Am met CERN physicist Rolf Landua after the concert to ask many more questions on particles, CERN, and the origin of the Universe.

  10. Research of Embedded Tower Crane Monitoring System Based on FCS

    Xijian Zheng


    Full Text Available To compensate for the lack of traditional safety limit device of tower crane, a design scheme of embedded tower crane intelligent monitoring system based on Fieldbus Control System was proposed. By this, online collection and transmission of tower crane real-time conditions were achieved, which could effectively improve the reliability and anti-interference of the system. Embedded development technology was used to build ARM-based master control platform. Embedded Linux cross-compiler environment was also built. Combining with embedded programming software, human-computer interaction interface of tower crane intelligent monitoring system was built, storage and display of tower crane’s online parameters were also realized. The use of the technology has opened up a new field of tower crane condition monitoring application. The research of this paper may provide reference for tower crane safety monitoring and fault diagnosing.

  11. Simplified models for assessing heat and mass transfer in evaporative towers

    Angelis, Alessandra De; Lorenzini, Giulio


    The aim of this book is to supply valid and reasonable parameters in order to guide the choice of the right model of industrial evaporative tower according to operating conditions which vary depending on the particular industrial context: power plants, chemical plants, food processing plants and other industrial facilities are characterized by specific assets and requirements that have to be satisfied. Evaporative cooling is increasingly employed each time a significant water flow at a temperature which does not greatly differ from ambient temperature is needed for removing a remarkable heat l




    Full Text Available Transmission line towers are used to support conductors carrying extra high voltage (EHV electric transmission lines and one or two ground wires at suitable distance. These also carry vary heavy currents, to the tune of several hundred amperes. This has necessitated the use of tall towers to support the transmission line conductors carrying EHV. The cost of transmission line tower is 30% to 40% of total cost of transmission line. The problem of efficiently designing structural system involves reliability constraints imposed at both serviceability and ultimate limit state. Methods are developed using structural reliability principle to evaluate time dependent reliability of structure. These methods enable the impact on safety and serviceability of uncertainties in loading conditions, structural degradation due to aggressive environment to be assessed qualitatively. The prediction of service life of damaged or deteriorated steel structures remains at the stage of parametric studies, inspite of intensive research on corrosion in steel structures for the past three decades. Service live of steel structures is limited by the susceptibility of the member to corrosion. Oxidation of iron leads to the formulation of various products (such as ferrous and ferric oxides, some of which occupy much greater volume than the original iron that gets consumed by the corrosion process. At this stage the member loses its ability to resist the forces. This project is a study on reliability assessment of 220 kV transmission towers. In this the 220 kV tower consists of 33.935 m height arranged in 12 height Panels and it contain 225 members. The wind load on tower for zone –II condition is calculated according to IS Code IS: 802 (part – 1/Section – 1: 1995. The tower is analyzed as space truss for full load condition using STAAD Pro 2007. In this work the variation of reliability index of members with decrease in area of cross section are studied. The compression

  13. 北京市顺义区涉奥场所淋浴热水及中央空调冷却塔水嗜肺军团菌污染调查%Investigation of Water Contamination of Cooling Towers of Centralized Air Conditioning and Shower Caused by Legionella Pneumophila in Olympics-related Places in Shunyi District of Beijing

    王瑞霞; 刘晓涛; 荆洪波; 梁和平; 甄国新; 黄晓凤; 谈敦芳


    [Objective]To ensure the Beijing Olympic Games holding harmoniously and successfully, to provide healthy and safe public places for the world's athletes and guests, and provide technical guidance for health security in Shunyi District during the Olympic Games.[Methods]Shunyi Center for Disease Control and Prevention (CDC) investigated shower hot water and central air conditioning cooling water samples from 8 Olympic related public places in July 11 to August 8, 2008. According to appendix A.1, methods for detecting of Legionella pneumophila, of Beijing local standards, BDI 1/485-2007 "Health Management Norms of Central Air Conditioning Ventilation System in Public Places," legionella pneumophila was detected whether existed in water samples.[Results]In all 6 hot water samples, 2 samples were detected legionella, the detection rate was 33.3%; and 2 of l 8 cooling water samples was positive, the detection rate was 11.1%.[Conclusion]Legionella contamination exists in central air-conditioning cooling water and shower hot water in Shunyi district, it is proposed to strengthen the monitoring of legionella in the environmental water.%目的 为了保障北京奥运会和谐、顺利举办,向中外运动员及宾客提供安全卫生的公共场所,为顺义区奥运卫生保障提供技术指导.方法 顺义区疾病预防控制中心于2008年7月11日-8月12日对顺义区8家涉奥公共场所的淋浴热水及中央空调冷却水水样进行调查.依据北京市地方标准BD 11/485-2007附录A.1空调系统冷却(凝)水中嗜肺军团菌检验方法,对水样中的军团菌进行检测.结果 共采集淋浴热水6件,2件检出嗜肺军团菌,检出率为33.3%;采集冷却水18件,2件检出嗜肺军团菌,检出率为11.1%.结论 顺义区中央空调冷却塔水及生活热水中存在军团菌污染,建议加强对环境水中军团菌的监测.

  14. Wind-induced response analysis of a wind turbine tower including the blade-tower coupling effect

    Xiao-bo CHEN; Jing LI; Jian-yun CHEN


    To analyze wind-induced response characteristics of a wind turbine tower more accurately, the blade-tower coupling effect was investigated. The mean wind velocity of the rotating blades and tower was simulated according to wind shear effects,and the fluctuating wind velocity time series of the wind turbine were simulated by a harmony superposition method. A dynamic finite element method (FEM) was used to calculate the wind-induced response of the blades and tower. Wind-induced responses of the tower were calculated in two cases (one included the blade-tower coupling effect, and the other only added the mass of blades and the hub at the top of the tower), and then the maximal displacements at the top of the tower of the tow cases were compared with each other. As a result of the influence of the blade-tower coupling effect and the total base shear of the blades, the maximal displacement of the first case increased nearly by 300% compared to the second case. To obtain more precise analysis, the blade-tower coupling effect and the total base shear of the blades should be considered simultaneously in the design of wind turbine towers.

  15. International Ventilation Cooling Application Database

    Holzer, Peter; Psomas, Theofanis Ch.; OSullivan, Paul


    The currently running International Energy Agency, Energy and Conservation in Buildings, Annex 62 Ventilative Cooling (VC) project, is coordinating research towards extended use of VC. Within this Annex 62 the joint research activity of International VC Application Database has been carried out, ...

  16. Dynamic analysis of the Milad Tower

    Wilhelm, Edwin; Ford, Mitchell; Coelho, Darren; Lawler, Lachlan; Ansourian, Peter; Alonso-Marroquin, Fernando; Tahmasebinia, Faham


    This report involves the modelling of the Milad Tower using the finite element analysis program Strand7. A dynamic analysis was performed on the structure in order to understand the deflections and stresses as a result of earthquake and wind loading. In particular, Linear Static as well as Natural Frequency and Spectral Response solvers were used to determine the behaviour of the structure under loading. The findings of the report highlight that the structure was modelled accurately with the outputs representing realistic values. The report suggests that the design of the beams, columns, slabs and all structural members was sufficient enough to support the tower during maximum loading cases. The governing load case was earthquake loading.

  17. Solar Physics at the Einstein Tower

    Denker, C; Rendtel, J; Arlt, K; Balthasar, H; Diercke, A; Manrique, S J González; Hofmann, A; Kuckein, C; Önel, H; Pavai, V Senthamizh; Staude, J; Verma, M


    The solar observatory Einstein Tower (Einsteinturm) at the Telegrafenberg in Potsdam is both a landmark of modern architecture and an important place for solar physics. Originally built for high-resolution spectroscopy and measuring the gravitational redshift, research shifted over the years to understanding the active Sun and its magnetic field. Nowadays, telescope and spectrographs are used for research and development, i.e., testing instruments and in particular polarization optics for advanced instrumentation deployed at major European and international astronomical and solar telescopes. In addition, the Einstein Tower is used for educating and training of the next generation astrophysicists as well as for education and public outreach activities directed at the general public. This article comments on the observatory's unique architecture and the challenges of maintaining and conserving the building. It describes in detail the characteristics of telescope, spectrographs, and imagers; it portrays some of ...

  18. Solar physics at the Einstein Tower

    Denker, C.; Heibel, C.; Rendtel, J.; Arlt, K.; Balthasar, Juergen H.; Diercke, A.; González Manrique, S. J.; Hofmann, A.; Kuckein, C.; Önel, H.; Senthamizh Pavai, V.; Staude, J.; Verman, M.


    The solar observatory Einstein Tower ({Einsteinturm}) at the Telegrafenberg in Potsdam is both a landmark of modern architecture and an important place for solar physics. Originally built for high-resolution spectroscopy and measuring the gravitational redshift, research shifted over the years to understanding the active Sun and its magnetic field. Nowadays, telescope and spectrographs are used for research and development, i.e., testing instruments and in particular polarization optics for advanced instrumentation deployed at major European and international astronomical and solar telescopes. In addition, the Einstein Tower is used for educating and training of the next generation astrophysicists as well as for education and public outreach activities directed at the general public. This article comments on the observatory's unique architecture and the challenges of maintaining and conserving the building. It describes in detail the characteristics of telescope, spectrographs, and imagers; it portrays some of the research and development activities.

  19. Optical study of solar tower power plants

    Eddhibi, F.; Ben Amara, M.; Balghouthi, M.; Guizani, A.


    The central receiver technology for electricity generation consists of concentrating solar radiation coming from the solar tracker field into a central receiver surface located on the top of the tower. The heliostat field is constituted of a big number of reflective mirrors; each heliostat tracks the sun individually and reflects the sunlight to a focal point. Therefore, the heliostat should be positioned with high precision in order to minimize optical losses. In the current work, a mathematical model for the analysis of the optical efficiency of solar tower field power plant is proposed. The impact of the different factors which influence the optical efficiency is analyzed. These parameters are mainly, the shading and blocking losses, the cosine effect, the atmospheric attenuation and the spillage losses. A new method for the calculation of blocking and shadowing efficiency is introduced and validated by open literature.

  20. Damping of wind turbine tower vibrations

    Brodersen, Mark Laier; Pedersen, Mikkel Melters

    Damping of wind turbine vibrations by supplemental dampers is a key ingredient for the continuous use of monopiles as support for offshore wind turbines. The present thesis consists of an extended summary with four parts and appended papers [P1-P4] concerning novel strategies for damping of tower...... dominated vibrations.The first part of the thesis presents the theoretical framework for implementation of supplemental dampers in wind turbines. It is demonstrated that the feasibility of installing dampers at the bottom of the tower is significantly increased when placing passive or semiactive dampers...... that a minimum of three braces in a symmetric circumferential configuration are needed to introduce homogeneous damping in the two lowest vibration modes, independent of the rotor direction. A novel hybrid viscous damper concept is described in the second part. The hybriddamper consists of a viscous dash...