Sample records for wind tower network

  1. Towers for Offshore Wind Turbines

    NASA Astrophysics Data System (ADS)

    Kurian, V. J.; Narayanan, S. P.; Ganapathy, C.

    2010-06-01

    Increasing energy demand coupled with pollution free production of energy has found a viable solution in wind energy. Land based windmills have been utilized for power generation for more than two thousand years. In modern times wind generated power has become popular in many countries. Offshore wind turbines are being used in a number of countries to tap the energy from wind over the oceans and convert to electric energy. The advantages of offshore wind turbines as compared to land are that offshore winds flow at higher speed than onshore winds and the more available space. In some land based settings, for better efficiency, turbines are separated as much as 10 rotor diameters from each other. In offshore applications where only two wind directions are likely to predominate, the distances between the turbines arranged in a line can be shortened to as little as two or four rotor diameters. Today, more than a dozen offshore European wind facilities with turbine ratings of 450 kw to 3.6 MW exist offshore in very shallow waters of 5 to 12 m. Compared to onshore wind turbines, offshore wind turbines are bigger and the tower height in offshore are in the range of 60 to 80 m. The water depths in oceans where offshore turbines can be located are within 30 m. However as the distance from land increases, the costs of building and maintaining the turbines and transmitting the power back to shore also increase sharply. The objective of this paper is to review the parameters of design for the maximum efficiency of offshore wind turbines and to develop types offshore towers to support the wind turbines. The methodology of design of offshore towers to support the wind turbine would be given and the environmental loads for the design of the towers would be calculated for specific cases. The marine corrosion on the towers and the methods to control the corrosion also would be briefly presented. As the wind speeds tend to increase with distance from the shore, turbines build father offshore will be able to capture more wind energy. Currently two types of towers are considered. Cylindrical tubular structures and truss type structures. But truss type structures have less weight and flexibility in design. The construction of the offshore towers to harness the wind energy is also presented. The results will include the calculation of wind and wave forces on the tower and the design details for the tower.

  2. Wind tower augmentation of wind turbines

    NASA Astrophysics Data System (ADS)

    Bahadori, M. N.

    The operating principle of the 'Baud-Geers' wind towers traditionally used in Iran for ventilation and passive cooling of architectural structures is presently adapted to house a vertical axis wind turbine. Unlike annular diffuser-augmented, horizontal axis wind turbines, the 'wind tower' does not have to be trained into the wind and generates less noise. It may also be either free standing or incorporated into the structure of existing buildings. Attention is given to the continuity and energy equations of this system, and to the results of wind tunnel model testing which ascertained turbine load factor and augmentation ratio.

  3. Probabilistic analysis of mean-response along-wind induced vibrations on wind turbine towers using wireless network data sensors

    NASA Astrophysics Data System (ADS)

    Velazquez, Antonio; Swartz, Raymond A.

    2011-04-01

    Wind turbine systems are attracting considerable attention due to concerns regarding global energy consumption as well as sustainability. Advances in wind turbine technology promote the tendency to improve efficiency in the structure that support and produce this renewable power source, tending toward more slender and larger towers, larger gear boxes, and larger, lighter blades. The structural design optimization process must account for uncertainties and nonlinear effects (such as wind-induced vibrations, unmeasured disturbances, and material and geometric variabilities). In this study, a probabilistic monitoring approach is developed that measures the response of the turbine tower to stochastic loading, estimates peak demand, and structural resistance (in terms of serviceability). The proposed monitoring system can provide a real-time estimate of the probability of exceedance of design serviceability conditions based on data collected in-situ. Special attention is paid to wind and aerodynamic characteristics that are intrinsically present (although sometimes neglected in health monitoring analysis) and derived from observations or experiments. In particular, little attention has been devoted to buffeting, usually non-catastrophic but directly impacting the serviceability of the operating wind turbine. As a result, modal-based analysis methods for the study and derivation of flutter instability, and buffeting response, have been successfully applied to the assessment of the susceptibility of high-rise slender structures, including wind turbine towers. A detailed finite element model has been developed to generate data (calibrated to published experimental and analytical results). Risk assessment is performed for the effects of along wind forces in a framework of quantitative risk analysis. Both structural resistance and wind load demands were considered probabilistic with the latter assessed by dynamic analyses.

  4. Evaluation of a wind power parameterization using tower observations

    Microsoft Academic Search

    Steven M. Lazarus; Jennifer Bewley

    2005-01-01

    The spatial and temporal components of a published wind power parameterization method are evaluated using observed winds (9 m to 90 m) from 7 years of data collected at four towers in the Kennedy Space Center\\/Cape Canaveral Air Force Station network. The temporal component is governed by two parameterization inputs which represent the amplitude and mean of an assumed sinusoidal

  5. Towers for Offshore Wind Turbines

    Microsoft Academic Search

    V. J. Kurian; S. P. Narayanan; C. Ganapathy

    2010-01-01

    Increasing energy demand coupled with pollution free production of energy has found a viable solution in wind energy. Land based windmills have been utilized for power generation for more than two thousand years. In modern times wind generated power has become popular in many countries. Offshore wind turbines are being used in a number of countries to tap the energy

  6. Wind turbine tower for storing hydrogen and energy

    DOEpatents

    Fingersh, Lee Jay (Westminster, CO)

    2008-12-30

    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.

  7. Lifting system and apparatus for constructing wind turbine towers

    DOEpatents

    Livingston, Tracy; Schrader, Terry; Goldhardt, James; Lott, James

    2011-02-01

    The disclosed invention is utilized for mounting a wind turbine and blade assembly on the upper end of a wind turbine tower. The invention generally includes a frame or truss that is pivotally secured to the top bay assembly of the tower. A transverse beam is connected to the frame or truss and extends fore of the tower when the frame or truss is in a first position and generally above the tower when in a second position. When in the first position, a wind turbine or blade assembly can be hoisted to the top of the tower. The wind turbine or blade assembly is then moved into position for mounting to the tower as the frame or truss is pivoted to a second position. When the turbine and blade assembly are secured to the tower, the frame or truss is disconnected from the tower and lowered to the ground.

  8. Summary of tower designs for large horizontal axis wind turbines

    NASA Technical Reports Server (NTRS)

    Frederick, G. R.; Savino, J. M.

    1986-01-01

    Towers for large horizontal axis wind turbines, machines with a rotor axis height above 30 meters and rated at more than 500 kW, have varied in configuration, materials of construction, type of construction, height, and stiffness. For example, the U.S. large HAWTs have utilized steel truss type towers and free-standing steel cylindrical towers. In Europe, the trend has been to use only free-standing and guyed cylindrical towers, but both steel and reinforced concrete have been used as materials of construction. These variations in materials of construction and type of construction reflect different engineering approaches to the design of cost effective towers for large HAWTs. Tower designs are the NASA/DOE Mod-5B presently being fabricated. Design goals and requirements that influence tower configuration, height and materials are discussed. In particular, experiences with United States large wind turbine towers are elucidated. Finally, current trends in tower designs for large HAWTs are highlighted.

  9. 77 FR 37653 - Utility Scale Wind Towers From the People's Republic of China: Alignment of Final Countervailing...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-22

    ...Administration [C-570-982] Utility Scale Wind Towers From the People's Republic...duty (CVD) investigation of utility scale wind towers (wind towers) from the...1\\ See Utility Scale Wind Towers From the People's...

  10. Summary of tower designs for large horizontal axis wind turbines

    SciTech Connect

    Frederick, G.R.; Savino, J.M.

    1986-01-01

    Towers for large horizontal axis wind turbines, machines with a rotor axis height above 30 meters and rated at more than 500 kW, have varied in configuration, materials of construction, type of construction, height, and stiffness. For example, the US large HAWTs have utilized steel truss type towers and free-standing steel cylindrical towers. In Europe, the trend has been to use only free-standing and guyed cylindrical towers, but both steel and reinforced concrete have been used as materials of construction. These variations in materials of construction and type of construction reflect different engineering approaches to the design of cost effective towers for large HAWTs. Tower designs are reviewed beginning with the historic Smith-Putnam HAWT and progressing through the NASA/DOE Mod-5B presently being fabricated. Design goals and requirements that influence tower configuration, height and materials are discussed. In particular, experiences with United States large wind turbine towers are elucidated. Finally, current trends in tower designs for large HAWTs are highlighted. The material discussed in this paper will be beneficial to those companies contemplating the development and/or manufacture of large HAWTs. Foundation designs are not discussed in this paper.

  11. A Meso-Climatology Study of the High-Resolution Tower Network Over the Florida Spaceport

    NASA Technical Reports Server (NTRS)

    Case, Jonathan L.; Bauman, William H., III

    2004-01-01

    Forecasters at the US Air Force 45th Weather Squadron (45 WS) use wind and temperature data from the tower network over the Kennedy Space Center (KSC) and Cape Canaveral Air Force Station (CCAFS) to evaluate Launch Commit Criteria and to issue and verify temperature and wind advisories, watches, and warnings for ground operations. The Spaceflight Meteorology Group at the Johnson Space Center in Houston, TX also uses these data when issuing forecasts for shuttle landings at the KSC Shuttle Landing Facility. Systematic biases in these parameters at any of the towers could adversely affect an analysis, forecast, or verification for all of these operations. In addition, substantial geographical variations in temperature and wind speed can occur under specific wind directions. Therefore, the Applied Meteorology Unit (AMU), operated by ENSCO Inc., was tasked to develop a monthly and hourly climatology of temperatures and winds from the tower network, and identify the geographical variation, tower biases, and the magnitude of those biases. This paper presents a sub-set of results from a nine-year climatology of the KSC/CCAFS tower network, highlighting the geographical variations based on location, month, times of day, and specific wind direction regime. Section 2 provides a description of the tower mesonetwork and instrumentation characteristics. Section 3 presents the methodology used to construct the tower climatology including QC methods and data processing. The results of the tower climatology are presented in Section 4 and Section 5 summarizes the paper.

  12. Development of wind turbine towers using fiber reinforced polymers

    NASA Astrophysics Data System (ADS)

    Ungkurapinan, Nibong

    With an ongoing trend in the wind turbine market, the size of wind turbines has been increasing continuously. Larger wind turbines imply an increase in size, weight, and loads acting on the wind turbine tower. This requires towers to be stronger and stiffer, and consequently leads to bigger tower diameters. Because of their size and weight, transportation and erection require heavy equipment that makes the use of such towers prohibitive in remote communities. To tackle this problem, a research program was initiated at the University of Manitoba to develop the technology required for the fabrication of wind turbine towers constructed of fiber reinforced polymers (FRP) for use in remote communities in Canada. The research program was carried out in stages. During the first stage, a feasibility study and an analytical investigation on various shapes of FRP towers were conducted. The concept of a multi-cellular composite tower was examined in great detail and the finite element results showed that such a tower could result in almost 45 percent reduction in weight. In the second stage of this research program, a robotic filament winding machine was designed and constructed in the Composites Laboratory of the University of Manitoba. It was used to fabricate the multi-cell tower specimens for testing. The third stage of the research program involved the experimental investigation, which was carried out in three phases. In the first phase, two single cell specimens were tested to failure under lateral loading. The specimens were 8 ft (2.44 m) long. The second phase involved the testing of two single cells loaded in compression. The third phase of the experimental investigation involved the testing of two eight-cell jointed tower specimens. The specimens were octagonal and tapered, with a diameter of 21.4 in (543 mm) at the base and 17.4 in (441 mm) at the top. They were 16 ft (4.88 m) in height and tested as cantilever under static loading. Local buckling was the dominant failure mode of the specimens tested. One of these towers was subsequently repaired and retested to determine whether repairing would restore the original strength of the tower. The last stage of the research program, various finite element models were developed to analyze the structural behavior of tested specimens. The results from finite element models were validated through comparison with experimental results. The finite element models gave a very good prediction of the structural performance of the FRP towers tested.

  13. Galloping of internally resonant towers subjected to turbulent wind

    NASA Astrophysics Data System (ADS)

    Zulli, Daniele; Di Egidio, Angelo

    2014-09-01

    Bifurcation analysis of a structure constituted by two towers, linked by a viscous device at the tip and subjected to turbulent wind, is carried out. The towers have geometrical and mechanical parameters so that the steady part of the wind, whose contribution is evaluated in the framework of the steady theory, induces a 1:1 resonant double-Hopf bifurcation. The turbulent part of the wind, assumed as composed by two frequencies that are equal and double to the main frequency of the unlinked towers, respectively, induces parametric and external harmonic forces. These forces interact with the self-excitation due to the steady part of the wind, bringing imperfection in the bifurcation scenario. Transitions from resonant to non-resonant cases are analyzed in terms of behavior charts, and post-critical dynamics is studied in the space of bifurcation parameters.

  14. Computer Simulation of Cooling Effect of Wind Tower on Passively Ventilated Building

    E-print Network

    Seryak, J.; Kissock, J. K.

    2002-01-01

    . The net force upward on the air in the wind tower, Fnet, is: Fnet = Fi ? Fo - Fg (7) where Fi and Fo are the forces due to air pressure at the inlet and outlet of the wind tower, and Fg is the force... (10) where Ac is the cross sectional area of the wind tower, Pi and Po are the air pressures at the inlet and outlet of the wind tower, h is the height of the wind tower, rhoi is the density of air in the wind tower and g is the acceleration...

  15. 77 FR 14342 - Utility Scale Wind Towers From the People's Republic of China: Notice of Postponement of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-09

    ...Administration [C-570-982] Utility Scale Wind Towers From the People's Republic...countervailing duty investigation of utility scale wind towers from the People's Republic of China. See Utility Scale Wind Towers From the People's...

  16. 77 FR 29315 - Utility Scale Wind Towers From the People's Republic of China and the Socialist Republic of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-17

    ...A-570-981, A-552-814] Utility Scale Wind Towers From the People's Republic...antidumping duty investigations of utility scale wind towers from the People's Republic...1\\ See Utility Scale Wind Towers From the People's...

  17. Some techniques for reducing the tower shadow of the DOE/NASA mod-0 wind turbine tower. [wind tunnel tests to measure effects of tower structure on wind velocity

    NASA Technical Reports Server (NTRS)

    Burley, R. R.; Savino, J. M.; Wagner, L. H.; Diedrich, J. H.

    1979-01-01

    Wind speed profile measurements to measure the effect of a wind turbine tower on the wind velocity are presented. Measurements were made in the wake of scale models of the tower and in the wake of certain full scale components to determine the magnitude of the speed reduction (tower shadow). Shadow abatement techniques tested on the towers included the removal of diagonals, replacement of diagonals and horizontals with round cross section members, installation of elliptical shapes on horizontal members, installation of airfoils on vertical members, and application of surface roughness to vertical members.

  18. Simulation model of wind turbine 3p torque oscillations due to wind shear and tower shadow

    Microsoft Academic Search

    Dale S. L. Dolan; Peter W. Lehn

    2006-01-01

    To determine the control structures and possible power quality issues, the dynamic torque generated by the blades of a wind turbine must be represented. This paper presents an analytical formulation of the generated aerodynamic torque of a three-bladed wind turbine including the effects of wind shear and tower shadow. The comprehensive model includes turbine-specific parameters such as radius, height, and

  19. Simulation Model of Wind Turbine 3p Torque Oscillations due to Wind Shear and Tower Shadow

    Microsoft Academic Search

    Dale S. L. Dolan; P. W. Lehn

    2006-01-01

    To determine control structures and possible power quality issues, the dynamic torque generated by the blades of a wind turbine must be represented. This paper presents an analytical formulation of the generated aerodynamic torque of a three bladed wind turbine including effects of wind shear and tower shadow. The comprehensive model includes turbine specific parameters such as radius, height, and

  20. Numerical model for the flow within the tower of a tornado-type wind energy system

    SciTech Connect

    Ayad, S.S.

    1981-11-01

    A two-equation turbulence model is used to predict numerically the flow within the tower of a tornado-type wind energy system. Calculations are carried out for a tower in a uniform flow. Both cases of closed-bottom tower and simulated turbine flow with a variety of turbine-to-tower diameter ratios and turbine flow rates are considered. Calculated values of pressure for closed-bottom tower are compared with experimental values. 11 refs.

  1. The effectiveness of wind walls in reducing the intake flow rate into a cooling tower

    SciTech Connect

    Bender, T.J.; Rezkallah, K.S.; Bergstrom, D.J. [Univ. of Saskatchewan, Saskatoon, Saskatchewan (Canada). Dept. of Mechanical Engineering

    1995-12-31

    Cooling towers operating in western Canada are often subject to adverse weather, which can hinder their performance. In particular, during winter months, cooling towers may experience strong winds and sub-freezing temperatures, which can lead to large ice formations at the windward intake. These ice accumulations may be partly attributed to increased flow through the windward intake. The present study examines the use of wind walls placed upstream of the cooling tower to control the flow rate entering the intakes. A 1:25 scale model cooling tower was tested in the simulated atmospheric boundary layer of a wind tunnel to investigate the effect of different wind wall configurations.

  2. Analysis of Wind Characteristics at United States Tall Tower Measurement Sites

    NASA Astrophysics Data System (ADS)

    Elliott, D.; Schwartz, M.; Scott, G.; Haymes, S.

    2008-12-01

    A major initiative of the U.S. Department of Energy (DOE) is to ensure that 20% of the country's electricity is produced by wind energy by the year 2030. An understanding of the boundary layer characteristics, especially at elevated heights greater than 80 meters (m) above the surface is a key factor for wind turbine design, wind plant layout, and identifying potential markets for advanced wind technology. The wind resource group at the DOE National Renewable Energy Laboratory is analyzing wind data collected at tall (80+ m) towers across the United States. The towers established by both public and private initiative, measure wind characteristics at multiple levels above the surface, with the highest measurement levels generally between 80 and 110 m. A few locations have measurements above 200 m. Measurements of wind characteristics over a wide range of heights are useful to: (1) characterize the local and regional wind climate; (2) validate wind resource estimates derived from numerical models; and (3) directly assess and analyze specific wind resource characteristics such as wind speed shear over the turbine blade swept area. The majority of the available public tall tower measurement sites are located between the Appalachian and Rocky Mountains. The towers are not evenly distributed among the states. The states with the largest number of towers include Indiana, Iowa, Missouri, and Kansas. These states have five or six towers collecting data. Other states with multiple tower locations include Texas, Oklahoma, Minnesota, and Ohio. The primary consideration when analyzing the data from the tall towers is identifying tower flow effects that not only can produce slightly misleading average wind speeds, but also significantly misleading wind speed shear values. In addition, the periods-of-record of most tall tower data are only one to two years in length. The short data collection time frame does not significantly affect the diurnal wind speed pattern though it does complicate analysis of seasonal wind patterns. The tall tower data analysis revealed some distinct regional features of wind shear climatology. For example, the wind shear exponent (alpha) at the towers in the Central Plains is generally between 0.15 and 0.25, greater than the commonly used 1/7 power law exponent value of 0.143. Another characteristic of Central Plains wind climatology was that winds from the south had alpha values of 0.2 to 0.3, while northerly winds had lower alpha values from 0.1 to 0.2. The wind resource at a particular tower is affected not only by the regional climatology but also by local conditions such as terrain, surface roughness, and structure of the lower boundary layer.

  3. Wind Speeds as Measured by Cup and Sonic Anemometers and Influenced by Tower Structure

    Microsoft Academic Search

    Yutaka Izumi; Morton L. Barad

    1970-01-01

    Wind tunnel and field experiments have shown that the fast-response three-component sonic anemometer is a highly accurate wind speed sensor. When sonic anemometers were used as reference sensors for wind speed, slower response cup anemometers were found to consistently overestimate the wind speed. Despite measures taken during a field program in Kansas to minimize tower influence on wind measurements, the

  4. SHM BASED SYSTEM DESIGN OFA WIND TURBINE TOWER USING A MODAL SENSITIVITY BASED BAYES DETECTOR

    E-print Network

    Boyer, Edmond

    SHM BASED SYSTEM DESIGN OFA WIND TURBINE TOWER USING A MODAL SENSITIVITY BASED BAYES DETECTOR Mads of the NREL 5MW wind turbine tower subjected to bending fatigue and horizontal circumferential cracking of SHM malfunction. These threats make it difficult to find industrial partners for real world

  5. Performance prediction of a cooling tower using artificial neural network

    Microsoft Academic Search

    M. Hosoz; H. M. Ertunc; H. Bulgurcu

    2007-01-01

    This paper describes an application of artificial neural networks (ANNs) to predict the performance of a cooling tower under a broad range of operating conditions. In order to gather data for training and testing the proposed ANN model, an experimental counter flow cooling tower was operated at steady state conditions while varying the dry bulb temperature and relative humidity of

  6. Improvement of risk estimate on wind turbine tower buckled by hurricane

    E-print Network

    Li, Jingwei

    2013-01-01

    Wind is one of the important reasonable resources. However, wind turbine towers are sure to be threatened by hurricanes. In this paper, method to estimate the number of wind turbine towers that would be buckled by hurricanes is discussed. Monte Carlo simulations show that our method is much better than the previous one. Since in our method, the probability density function of the buckling probability of a single turbine tower in a single hurricane is obtained accurately but not from one approximated expression. The result in this paper may be useful to the design and maintenance of wind farms.

  7. Tower and rotor blade vibration test results for a 100-kilowatt wind turbine

    NASA Technical Reports Server (NTRS)

    Linscott, B. S.; Shapton, W. R.; Brown, D.

    1976-01-01

    The predominant natural frequencies and mode shapes for the tower and the rotor blades of the ERDA-NASA 100-kW wind turbine were determined. The tests on the tower and the blades were conducted both before and after the rotor blades and the rotating machinery were installed on top of the tower. The tower and each blade were instrumented with an accelerometer and impacted by an instrumented mass. The tower and blade structure was analyzed by means of NASTRAN, and computed values agree with the test data.

  8. Wake characteristics of a tower for the DOE-NASA MOD-1 wind turbine

    NASA Technical Reports Server (NTRS)

    Savino, J. M.; Wagner, L. H.; Nash, M.

    1978-01-01

    A 1/40th scale model of a tower concept designed for a MOD-1 wind power turbine was tested in a low speed wind tunnel. Wake wind speed profiles were measured, and from these were determined local values of wake minimum velocity ratio, average velocity ratio, and width over a range of tower elevations and wind approach angles. Comparison with results from two other all tubular models (MOD-0 and eight leg designs) tested earlier in the same tunnel indicated that wake width and flow blockage at the rotor plane of rotation were slightly larger for the MOD-1 tower than for the other two models. The differences in wake characteristics were attributed to differences in tower geometry and member dimensions.

  9. Wake characteristics of an eight-leg tower for a MOD-0 type wind turbine

    NASA Technical Reports Server (NTRS)

    Savino, J. M.; Wagner, L. H.; Sinclair, D.

    1977-01-01

    Low speed wind tunnel tests were conducted to determine the flow characteristics of the wake downwind of a 1/25th scale, all tubular eight leg tower concept suitable for application to the DOE-NASA MOD-0 wind power turbine. Measurements were made of wind speed profiles, and from these were determined the wake local minimum velocity, average velocity, and width for several wind approach angles. These data are presented herein along with tower shadow photographs and comparisons with data from an earlier lattice type, four leg tower model constructed of tubular members. Values of average wake velocity defect ratio and average ratio of wake width to blade radius for the eight leg model were estimated to be around 0.17 and 0.30, respectively, at the plane of the rotor blade. These characteristics suggest that the tower wake of the eight leg concept is slightly less than that of the four leg design.

  10. EERE News: World Trade Center's Freedom Tower to Feature Wind Turbines

    NSDL National Science Digital Library

    The DOE Office of Energy Efficiency and Renewable Energy posts a weekly electronic newsletter. This January 7, 2004 issue of features a story about the wind turbines which will be part of the forthcoming Freedom Tower to be located at the site of the World Trade Center. The story includes links to the press release from the architects, images of the Freedom Tower design, as well as images of the proposed wind turbine installation.

  11. Portuguese Lookout Towers Network Optimization Using Automatic Positioning Algorithms

    Microsoft Academic Search

    Joel P. Almeida; Paulo Relvas; Luís Silva; Filipe X. Catry; Francisco C. Rego; Teresa Santos

    Although new surveillance means have been deployed in Portugal in the last few years, such as automatic detection camera systems, the National Lookout Towers Network (NLTN) is still the main organized fire detection system, having a total of 236 observation posts. These posts have been placed gradually over the last decades, resulting in a under optimized network. To evaluate the

  12. Optimization research on the structure of horizontally-arranged indirect air-cooling tower under strong wind condition

    NASA Astrophysics Data System (ADS)

    Chen, Guoyong; Gu, Hongfang; Wang, Haijun; Qin, Yongbo

    2013-07-01

    Strong wind has a significant impact on the heat radiation of the air-cooling system. In this research, a numerical calculation model of 2×1000MW horizontally arranged air-cooling tower is established to simulate the flow distribution and heat exchanging capability of three different structures-horizontally-arranged indirect air-cooling tower, tower with guide wall outside, and tower with a cross wall inside-under high-speed wind and extreme-speed wind conditions. The result reveals that the structure with the guide wall outside the tower only works under strong wind condition while the structure with cross wall inside shows the anti-wind capability under both high-speed wind and extreme-speed wind conditions.

  13. Investigation of Natural Draft Cooling Tower Performance Using Neural Network

    NASA Astrophysics Data System (ADS)

    Mahdi, Qasim S.; Saleh, Saad M.; Khalaf, Basima S.

    In the present work Artificial Neural Network (ANN) technique is used to investigate the performance of Natural Draft Wet Cooling Tower (NDWCT). Many factors are affected the rang, approach, pressure drop, and effectiveness of the cooling tower which are; fill type, water flow rate, air flow rate, inlet water temperature, wet bulb temperature of air, and nozzle hole diameter. Experimental data included the effects of these factors are used to train the network using Back Propagation (BP) algorithm. The network included seven input variables (Twi, hfill, mw, Taiwb, Taidb, vlow, vup) and five output variables (ma, Taowb, Two, ?p, ?) while hidden layer is different for each case. Network results compared with experimental results and good agreement was observed between the experimental and theoretical results.

  14. Recycled Towers

    NSDL National Science Digital Library

    Integrated Teaching and Learning Program,

    Students learn about material reuse by designing and building the strongest and tallest towers they can, using only recycled materials. They follow design constraints and build their towers to withstand earthquake and high wind simulations.

  15. Shaking table test and numerical analysis of offshore wind turbine tower systems controlled by TLCD

    NASA Astrophysics Data System (ADS)

    Chen, Jianbing; Liu, Youkun; Bai, Xueyuan

    2015-03-01

    A wind turbine system equipped with a tuned liquid column damper (TLCD) is comprehensively studied via shaking table tests using a 1/13-scaled model. The effects of wind and wave actions are considered by inputting response-equivalent accelerations on the shaking table. The test results show that the control effect of the TLCD system is significant in reducing the responses under both wind-wave equivalent loads and ground motions, but obviously varies for different inputs. Further, a blade-hub-tower integrated numerical model for the wind turbine system is established. The model is capable of considering the rotational effect of blades by combining Kane's equation with the finite element method. The responses of the wind tower equipped with TLCD devices are numerically obtained and compared to the test results, showing that under both controlled and uncontrolled conditions with and without blades' rotation, the corresponding responses exhibit good agreement. This demonstrates that the proposed numerical model performs well in capturing the wind-wave coupled response of the offshore wind turbine systems under control. Both numerical and experimental results show that the TLCD system can significantly reduce the structural response and thus improve the safety and serviceability of the offshore wind turbine tower systems. Additional issues that require further study are discussed.

  16. A method to avoid negative damped low frequent tower vibrations for a floating, pitch controlled wind turbine

    Microsoft Academic Search

    T J Larsen; T D Hanson

    2007-01-01

    Wind turbines mounted on floating platforms is subjected to completely different and soft foundation properties, than seen for onshore wind turbines. This leads to much lower natural frequencies, related to the rigid body motion of the structure which again leads to an unfavorable coupling between tower motion and the pitch control of the turbine. The tower motion in combination with

  17. Wind stress measurements during the Tower Ocean Wave and Radar Dependence Experiment

    Microsoft Academic Search

    G. L. Geernaert; K. L. Davidson; S. E. Larsen; T. Mikkelsen

    1988-01-01

    During the Tower Ocean Wave and Radar Dependence Experiment (TOWARD), near-continuous measurements of the wind drag were conducted using the dissipation technique. An intercomparison between these measurements and direct stress magnitudes using a sonic anemometer was performed over 3 days of the experiment. The results indicated that the dissipation technique compared well to the directly determined values when conditions were

  18. NREL National Wind Technology Center (NWTC): M2 Tower; Boulder, Colorado (Data)

    DOE Data Explorer

    Jager, D.; Andreas, A.

    The National Wind Technology Center (NWTC), located at the foot of the Rocky Mountains near Boulder, Colorado, is a world-class research facility managed by NREL for the U.S. Department of Energy. NWTC researchers work with members of the wind energy industry to advance wind power technologies that lower the cost of wind energy through research and development of state-of-the-art wind turbine designs. NREL's Measurement and Instrument Data Center provides data from NWTC's M2 tower which are derived from instruments mounted on or near an 82 meter (270 foot) meteorological tower located at the western edge of the NWTC site and about 11 km (7 miles) west of Broomfield, and approximately 8 km (5 miles) south of Boulder, Colorado. The data represent the mean value of readings taken every two seconds and averaged over one minute. The wind speed and direction are measured at six heights on the tower and air temperature is measured at three heights. The dew point temperature, relative humidity, barometric pressure, totalized liquid precipitation, and global solar radiation are also available.

  19. Tower wake/blade interaction noise of a wind turbine

    NASA Astrophysics Data System (ADS)

    Nishiwaki, Hideo; Takeda, Katsumi

    1987-10-01

    A scale model of a 1.5m dia. two-bladed windturbine was used in an anechoic chamber that provided a free-stream velocity of 8m/s. The blades used were a 1.5/8 scale model of a test machine for a local energy utilization project promoted by the Science and Technology Agency. The height of the tower from the ground level was 1.8m. The acoustic measurements were made in a circle of 1.6m downstream from the machine at the height of the windmill centerline. The noise level of the on-axis spectra was about 15dB larger than that of the off-axis. This is a result of the dipole nature of the acoustic impulse. The Wortmann airfoil (FX 77-W series) was employed for the blade profiles and the Reynolds number was 10(5), based on the tip chord length. The experiment revealed that the sound intensity at each harmonic was not proportional to the axial and radial extents of the wake. The elliptic slender configuration was the quietest, while the square configuration was the loudest. From a practical point of view, it is suggested that the circular section is most suitable for the tower leg.

  20. Investigation on the impact of the environment wind velocity on the indirect air-cooling tower performance

    NASA Astrophysics Data System (ADS)

    Qin, Yongbo; Gu, Hongfang; Wang, Haijun; Chen, Guoyong

    2013-07-01

    The wind velocity plays a crucial role in the operation characteristic of indirect cooling tower. In this paper a 2×330MW vertical arrangement indirect air-cooled system was taken as research object, and numerical simulation method was used to analyze the relative influence of the wind speed, ranging from 4m/s to 18m/s, on the outlet water temperature of cooling tower, the outlet air temperature of radiator, the facing wind speed of the fan segment and on the outlet air speed of the cooling tower. The result shows that the impact of the natural wind speed on the cooling tower efficiency varies greatly and this impact increases as the wind speed increases.

  1. Numerical simulation of fluid flow and thermal performance of a dry-cooling tower under cross wind condition

    Microsoft Academic Search

    M. D. Su; G. F. Tang; S. Fu

    1999-01-01

    Using the finite volume method (FVM), the fluid flow and temperature distribution around and in a dry-cooling tower under cross wind are simulated numerically. Since the flow is turbulent, the k–? turbulence model is used. The numerical results are used to estimate the heat transfer between radiators of the tower and air around it. The numerical results are also compared

  2. A practical application combining wireless sensor networks and Internet of Things: Safety Management System for Tower Crane Groups.

    PubMed

    Zhong, Dexing; Lv, Hongqiang; Han, Jiuqiang; Wei, Quanrui

    2014-01-01

    The so-called Internet of Things (IoT) has attracted increasing attention in the field of computer and information science. In this paper, a specific application of IoT, named Safety Management System for Tower Crane Groups (SMS-TC), is proposed for use in the construction industry field. The operating status of each tower crane was detected by a set of customized sensors, including horizontal and vertical position sensors for the trolley, angle sensors for the jib and load, tilt and wind speed sensors for the tower body. The sensor data is collected and processed by the Tower Crane Safety Terminal Equipment (TC-STE) installed in the driver's operating room. Wireless communication between each TC-STE and the Local Monitoring Terminal (LMT) at the ground worksite were fulfilled through a Zigbee wireless network. LMT can share the status information of the whole group with each TC-STE, while the LMT records the real-time data and reports it to the Remote Supervision Platform (RSP) through General Packet Radio Service (GPRS). Based on the global status data of the whole group, an anti-collision algorithm was executed in each TC-STE to ensure the safety of each tower crane during construction. Remote supervision can be fulfilled using our client software installed on a personal computer (PC) or smartphone. SMS-TC could be considered as a promising practical application that combines a Wireless Sensor Network with the Internet of Things. PMID:25196106

  3. Vibration Based Wind Turbine Tower Foundation Design Utilizing Soil-Foundation-Structure Interaction

    NASA Astrophysics Data System (ADS)

    Al Satari, P. E. Mohamed; Hussain, S. E. Saif

    2008-07-01

    Wind turbines have been used to generate electricity as an alternative energy source to conventional fossil fuels. This case study is for multiple wind towers located at different villages in Alaska where severe arctic weather conditions exist. The towers are supported by two different types of foundations; large mat or deep piles foundations. Initially, a Reinforced Concrete (RC) mat foundation was utilized to provide the system with vertical and lateral support. Where soil conditions required it, a pile foundation solution was devised utilizing a 30? thick RC mat containing an embedded steel grillage of W18 beams supported by 20?-24? grouted or un-grouted piles. The mixing and casting of concrete in-situ has become the major source of cost and difficulty of construction at these remote Alaska sites. An all-steel foundation was proposed for faster installation and lower cost, but was found to impact the natural frequencies of the structural system by significantly softening the foundation system. The tower-foundation support structure thus became near-resonant with the operational frequencies of the wind turbine leading to a likelihood of structural instability or even collapse. A detailed 3D Finite-Element model of the original tower-foundation-pile system with RC foundation was created using SAP2000. Soil springs were included in the model based on soil properties obtained from the geotechnical consultant. The natural frequency from the model was verified against the tower manufacturer analytical and the experimental values. Where piles were used, numerous iterations were carried out to eliminate the need for the RC and optimize the design. An optimized design was achieved with enough separation between the natural and operational frequencies to prevent damage to the structural system eliminating the need for any RC encasement to the steel foundation or grouting to the piles.

  4. A method to avoid negative damped low frequent tower vibrations for a floating, pitch controlled wind turbine

    NASA Astrophysics Data System (ADS)

    Larsen, T. J.; Hanson, T. D.

    2007-07-01

    Wind turbines mounted on floating platforms is subjected to completely different and soft foundation properties, than seen for onshore wind turbines. This leads to much lower natural frequencies, related to the rigid body motion of the structure which again leads to an unfavorable coupling between tower motion and the pitch control of the turbine. The tower motion in combination with the aerodynamics and the pitch control will be poor or even negative damped which causes large transient loads if not accounted for. The reason for this low damping is shown to be caused by a too fast pitch regulation compared to the motion of the tower or in other words the lowest control-structure natural frequency must be lower than the lowest critical tower frequency. A control algorithm is presented including the tuning method (pole-placement) to ensure the desired control frequency which provides stable tower vibration modes.

  5. Assessment of wind turbine seismic risk : existing literature and simple study of tower moment demand.

    SciTech Connect

    Prowell, Ian (University of California, San Diego, CA); Veers, Paul S.

    2009-03-01

    Various sources of risk exist for all civil structures, one of which is seismic risk. As structures change in scale, the magnitude of seismic risk changes relative to risk from other sources. This paper presents an introduction to seismic hazard as applied to wind turbine structures. The existing design methods and research regarding seismic risk for wind turbines is then summarized. Finally a preliminary assessment is made based on current guidelines to understand how tower moment demand scales as rated power increases. Potential areas of uncertainty in the application of the current guidelines are summarized.

  6. Comparison of Triton SODAR Data to Meteorological Tower Wind Measurement Data in Hebei Province, China

    SciTech Connect

    Yuechun, Y.; Jixue, W.; Hongfang, W.; Guimin, L.; Bolin, Y.; Scott, G.; Elliott, D.; Kline, D.

    2012-01-01

    With the increased interest in remote sensing of wind information in recent years, it is important to determine the reliability and accuracy of new wind measurement technologies if they are to replace or supplement conventional tower-based measurements. In view of this, HydroChina Corporation and the United States National Renewable Energy Laboratory (NREL) conducted a comparative test near a wind farm in Hebei Province, China. We present the results of an analysis characterizing the measurement performance of a state-of-the-art Sound Detection and Ranging (sodar) device when compared to a traditional tower measurement program. NREL performed the initial analysis of a three-month period and sent the results to HydroChina. When another month of data became available, HydroChina and their consultant Beijing Millenium Engineering Software (MLN) repeated NREL's analysis on the complete data set, also adding sensitivity analysis for temperature, humidity, and wind speed (Section 6). This report presents the results of HydroChina's final analysis of the four-month period.

  7. Influence of Multiple Cutouts on the Buckling of Large-Scale Thin-Walled Cylindrical Shells of Desulphurizing Tower under Wind Loading

    Microsoft Academic Search

    Dengfeng Wang; Yuanqing Wang; Yongjiu Shi; Pingzhou Cao

    2011-01-01

    The desulphurizing tower used in the power plant is the key environmental protection facility to eliminate the air pollution. Multiple cutouts are opened on the tower wall because of the technology requirement. The presence of multiple cutouts will influence the stability of tower under wind loading. On the project background of the large-scale thin-walled cylindrical shells of a practical desulphurizing

  8. Space-time VMS computation of wind-turbine rotor and tower aerodynamics

    NASA Astrophysics Data System (ADS)

    Takizawa, Kenji; Tezduyar, Tayfun E.; McIntyre, Spenser; Kostov, Nikolay; Kolesar, Ryan; Habluetzel, Casey

    2014-01-01

    We present the space-time variational multiscale (ST-VMS) computation of wind-turbine rotor and tower aerodynamics. The rotor geometry is that of the NREL 5MW offshore baseline wind turbine. We compute with a given wind speed and a specified rotor speed. The computation is challenging because of the large Reynolds numbers and rotating turbulent flows, and computing the correct torque requires an accurate and meticulous numerical approach. The presence of the tower increases the computational challenge because of the fast, rotational relative motion between the rotor and tower. The ST-VMS method is the residual-based VMS version of the Deforming-Spatial-Domain/Stabilized ST (DSD/SST) method, and is also called "DSD/SST-VMST" method (i.e., the version with the VMS turbulence model). In calculating the stabilization parameters embedded in the method, we are using a new element length definition for the diffusion-dominated limit. The DSD/SST method, which was introduced as a general-purpose moving-mesh method for computation of flows with moving interfaces, requires a mesh update method. Mesh update typically consists of moving the mesh for as long as possible and remeshing as needed. In the computations reported here, NURBS basis functions are used for the temporal representation of the rotor motion, enabling us to represent the circular paths associated with that motion exactly and specify a constant angular velocity corresponding to the invariant speeds along those paths. In addition, temporal NURBS basis functions are used in representation of the motion and deformation of the volume meshes computed and also in remeshing. We name this "ST/NURBS Mesh Update Method (STNMUM)." The STNMUM increases computational efficiency in terms of computer time and storage, and computational flexibility in terms of being able to change the time-step size of the computation. We use layers of thin elements near the blade surfaces, which undergo rigid-body motion with the rotor. We compare the results from computations with and without tower, and we also compare using NURBS and linear finite element basis functions in temporal representation of the mesh motion.

  9. Space-Time VMS Computation of Wind-Turbine Rotor and Tower Aerodynamics

    NASA Astrophysics Data System (ADS)

    McIntyre, Spenser W.

    This thesis is on the space{time variational multiscale (ST-VMS) computation of wind-turbine rotor and tower aerodynamics. The rotor geometry is that of the NREL 5MW offshore baseline wind turbine. We compute with a given wind speed and a specified rotor speed. The computation is challenging because of the large Reynolds numbers and rotating turbulent ows, and computing the correct torque requires an accurate and meticulous numerical approach. The presence of the tower increases the computational challenge because of the fast, rotational relative motion between the rotor and tower. The ST-VMS method is the residual-based VMS version of the Deforming-Spatial-Domain/Stabilized ST (DSD/SST) method, and is also called "DSD/SST-VMST" method (i.e., the version with the VMS turbulence model). In calculating the stabilization parameters embedded in the method, we are using a new element length definition for the diffusion-dominated limit. The DSD/SST method, which was introduced as a general-purpose moving-mesh method for computation of ows with moving interfaces, requires a mesh update method. Mesh update typically consists of moving the mesh for as long as possible and remeshing as needed. In the computations reported here, NURBS basis functions are used for the temporal representation of the rotor motion, enabling us to represent the circular paths associated with that motion exactly and specify a constant angular velocity corresponding to the invariant speeds along those paths. In addition, temporal NURBS basis functions are used in representation of the motion and deformation of the volume meshes computed and also in remeshing. We name this "ST/NURBS Mesh Update Method (STNMUM)." The STNMUM increases computational efficiency in terms of computer time and storage, and computational exibility in terms of being able to change the time-step size of the computation. We use layers of thin elements near the blade surfaces, which undergo rigid-body motion with the rotor. We compare the results from computations with and without tower, and we also compare using NURBS and linear finite element basis functions in temporal representation of the mesh motion.

  10. The PNL single-tower measurement model of rotationally sampled turbulent wind, with user's guide for STRS2PC

    SciTech Connect

    Connell, J.R.; Morris, V.R.; Powell, D.C.; Gower, G.L.

    1988-06-01

    This report describes a single-tower rotationally sampled wind model, STRS-2, that approximates a set of time series of turbulent wind experienced by individual points rotating in circles in a crosswind plane using measurements from anemometers arrayed vertically along a single line. The purposes of the model are (1) to use turbulence measurements made economically from conventional single-tower arrays of anemometers, (2) to incorporate measures characteristics of the wind at specific sites under consideration for operation of wind turbines, spanning the height range if interest, and (3) to estimate the unmeasured turbulence characteristics in the crosswind plane that spans the disk of the rotor blades. 17 refs., 15 figs., 5 tabs.

  11. US Wind Farmers Network

    SciTech Connect

    Lisa Daniels; DOE Project Officer - Keith Bennett

    2005-04-15

    Through this program Windustry representatives have produced, widely used, and distributed new materials and have participated in a wide variety of wind energy events, meetings, and conferences. In this work Windustry representatives have sought to reach a broad audience and grow interest and enthusiasm for wind energy. At the same time, Windustry representatives have sought to provide tools, detailed case studies, and other technical resources that deepen Windustry constituency's knowledge of wind energy options. All of this has served to facilitate development of many actual wind energy projects, particularly projects that emphasize local and community benefits.

  12. Design, fabrication, and initial test of a fixture for reducing the natural frequency of the Mod-O wind turbine tower

    NASA Technical Reports Server (NTRS)

    Winemiller, J. R.; Sullivan, T. L.; Sizemore, R. L.; Yee, S. T.

    1979-01-01

    It was desired to observe the behavior of a two bladed wind turbine where the tower first bending natural frequency is less than twice the rotor speed. The system then passes through resonance when accelerating to operating speed. The frequency of the original Mod-O tower was reduced by placing it on a spring fixture. The fixture is adjustable to provide a range of tower bending frequencies. Fixture design details are given and behavior during initial operation is described.

  13. Effect of rotor configuration on guyed tower and foundation designs and estimated costs for intermediate site horizontal axis wind turbines

    NASA Technical Reports Server (NTRS)

    Frederick, G. R.; Winemiller, J. R.; Savino, J. M.

    1982-01-01

    Three designs of a guyed cylindrical tower and its foundation for an intermediate size horizontal axis wind turbine generator are discussed. The primary difference in the three designs is the configuration of the rotor. Two configurations are two-blade rotors with teetering hubs - one with full span pitchable blades, the other with fixed pitch blades. The third configuration is a three-bladed rotor with a rigid hub and fixed pitch blades. In all configurations the diameter of the rotor is 38 meters and the axis of rotation is 30.4 meters above grade, and the power output is 200 kW and 400 kW. For each configuration the design is based upon for the most severe loading condition either operating wind or hurricane conditions. The diameter of the tower is selected to be 1.5 meters (since it was determined that this would provide sufficient space for access ladders within the tower) with guy rods attached at 10.7 meters above grade. Completing a design requires selecting the required thicknesses of the various cylindrical segments, the number and diameter of the guy rods, the number and size of soil anchors, and the size of the central foundation. The lower natural frequencies of vibration are determined for each design to ensure that operation near resonance does not occur. Finally, a cost estimate is prepared for each design. A preliminary design and cost estimate of a cantilever tower (cylindrical and not guyed) and its foundation is also presented for each of the three configurations.

  14. Constraining CO2 tower measurements in an inhomogeneous area with anthropogenic emissions using a combination of car-mounted instrument campaigns, aircraft profiles, transport modeling and neural networks

    NASA Astrophysics Data System (ADS)

    Schmidt, A.; Rella, C.; Conley, S. A.; Goeckede, M.; Law, B. E.

    2013-12-01

    The NOAA CO2 observation network in Oregon has been enhanced by 3 new towers in 2012. The tallest tower in the network (270 m), located in Silverton in the Willamette Valley is affected by anthropogenic emissions from Oregon's busiest traffic routes and urban centers. In summer 2012, we conducted a measurement campaign using a car-mounted PICARRO CRDS CO2/CO analyzer. Over 3 days, the instrument was driven over 1000 miles throughout the northwestern portion of Oregon measuring the CO/ CO2 ratios on main highways, back roads in forests, agricultural sites, and Oregon's biggest urban centers. By geospatial analyses we obtained ratios of CO/ CO2 over distinct land cover types divided into 10 classes represented in the study area. Using the coupled WRF-STILT transport model we calculated the footprints of nearby CO/ CO2 observation towers for the corresponding days of mobile road measurements. Spatiotemporally assigned source areas in combination with the land use classification were then used to calculate specific ratios of CO (anthropogenic origins) and CO2 to separate the anthropogenic portion of CO2 from the mixing ratio time series measured at the tower in Silverton. The WRF modeled boundary layer heights used in out study showed some differences compared to the boundary layer heights derived from profile data of wind, temperature, and humidity measured with an airplane in August, September, and November 2012, repeatedly over 5 tower locations. A Bayesian Regularized Artificial Neural Network (BRANN) was used to correct the boundary layer height calculated with WRF with a temporal resolution of 20 minutes and a horizontal resolution of 4 km. For that purpose the BRANN was trained using height profile data from the flight campaigns and spatiotemporally corresponding meteorological data from WRF. Our analyses provide information needed to run inverse modeling of CO2 exchange in an area that is affected by sources that cannot easily be considered by biospheric models. The results help to account for regional anthropogenic influences using long-term tower data and supporting short-term campaigns. Figure 1: The footprint areas of 2 NOAA observation towers (72 m inlet at Walton and 212 m inlet at Silverton) during the 3-day campaign with the car-mounted PICARRO CRDS on July 10 (a), July 11 (b), and July 12 (c) 2012 together with the main roads and urban centers. The orange lines show the routes driven during those days.

  15. A virtual tall tower network for understanding continental sources and sinks of CO2

    SciTech Connect

    Davis, K.J.; Richardson, S.J.; Miles, N.L.

    2007-03-09

    Our understanding of the North American terrestrial carbon cycle is limited by both a lack of continental atmospheric CO2 data, and by a need for methods to interpret these and other continental data with confidence. In response to this challenge a rapid expansion of the N. American carbon cycle observational network is underway. This expansion includes a network of continuous, continental CO2 mixing ratio observations being collected at a subset of AmeriFlux towers. Progress in developing this resource includes instrument development, site installation, calibration and intercalibration efforts, and initiation of a uniform data product. Progess in applying these data include proposed methods for interpreting surface layer measurements in atmospheric inversions (the virtual tall towers approach), examination of coherence patterns in continental mixing ratios in response to weather and climate, and application of these mixing ratio measurements in formal atmospheric inversions. Future work will merge these methods with interpretation of flux towers observations of terrestrial carbon fluxes in an effort to create a single coherent diagnosis of North American terrestrial carbon fluxes over a multi-year period.

  16. Effect of rotor configuration on guyed tower and foundation designs and estimated costs for intermediate-size horizontal-axis wind turbines

    SciTech Connect

    Frederick, G.R.; Winemiller, J.R.; Savino, J.M.

    1982-03-01

    Three designs of a guyed cylindrical tower and its foundation for an intermediate size horizontal axis wind turbine generator are discussed. The primary difference in the three designs is the configuration of the rotor. Two configurations are two-blade rotors with teetering hubs - one with full span pitchable blades, the other with fixed pitch blades. The third configuration is a three-bladed rotor with a rigid hub and fixed pitch blades. In all configurations the diameter of the rotor is 38 meters and the axis of rotation is 30.4 meters above grade, and the power output is 200 kW and 400 kW. For each configuration the design is based upon for the most severe loading condition - either operating wind or hurricane conditions. The diameter of the tower is selected to be 1.5 meters (since it was determined that this would provide sufficient space for access ladders within the tower) with guy rods attached at 10.7 meters above grade. Completing a design requires selecting the required thicknesses of the various cylindrical segments, the number and diameter of the guy rods, the number and size of soil anchors, and the size of the central foundation. The lower natural frequencies of vibration are determined for each design to ensure that operation near resonance does not occur. Finally, a cost estimate is prepared for each design. A preliminary design and cost estimate of a cantilever tower (cylindrical and not guyed) and its foundation is also presented for each of the three configurations. The estimated costs of the guyed towers and the cantilever towers are compared with the installed costs of truss type towers and foundations of the 200 kW Mod-0A wind turbines at Block Island and Culebra.

  17. Analysis of Wind Characteristics at United States Tall Tower Measurement Sites

    Microsoft Academic Search

    D. Elliott; M. Schwartz; G. Scott; S. Haymes

    2008-01-01

    A major initiative of the U.S. Department of Energy (DOE) is to ensure that 20% of the country's electricity is produced by wind energy by the year 2030. An understanding of the boundary layer characteristics, especially at elevated heights greater than 80 meters (m) above the surface is a key factor for wind turbine design, wind plant layout, and identifying

  18. The effect of the heat exchanger arrangement and wind-break walls on the performance of natural draft dry-cooling towers subjected to cross-winds

    Microsoft Academic Search

    A. F. du Preez; D. G. Kröger

    1995-01-01

    In most full scale dry-cooling towers rectangular heat exchanger bundles are arranged either vertically around the circumference of the tower or horizontally in the inlet cross-section of the tower. A numerical procedure is used in the present paper to investigate the influence of the particular arrangement on the performance of a tower in windy conditions with the results being verified

  19. 77 FR 33422 - Utility Scale Wind Towers From the People's Republic of China: Preliminary Affirmative...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-06

    ...Product Co., Ltd. (Titan Metal) and changed to...L. Award for Baotou Rare Earth High and New Technology...Wind), Titan Lianyungang Metal Products Co. Ltd. (Titan...and Shenyang Titan Metal Co., Ltd. (Titan...

  20. Mapping AmeriFlux footprints: Towards knowing the flux source area across a network of towers

    NASA Astrophysics Data System (ADS)

    Menzer, O.; Pastorello, G.; Metzger, S.; Poindexter, C.; Agarwal, D.; Papale, D.

    2014-12-01

    The AmeriFlux network collects long-term carbon, water and energy flux measurements obtained with the eddy covariance method. In order to attribute fluxes to specific areas of the land surface, flux source calculations are essential. Consequently, footprint models can support flux up-scaling exercises to larger regions, often based on remote sensing data. However, flux footprints are not currently being routinely calculated; different approaches exist but have not been standardized. In part, this is due to varying instrumentation and data processing methods at the site level. The goal of this work is to map tower footprints for a future standardized AmeriFlux product to be generated at the network level. These footprints can be estimated by analytical models, Lagrangian simulations, and large-eddy simulations. However, for many sites, the datasets currently submitted to central databases generally do not include all variables required. The AmeriFlux network is moving to collection of raw data and expansion of the variables requested from sites, giving the possibility to calculate all parameters and variables needed to run most of the available footprint models. In this pilot study, we are applying state of the art footprint models across a subset of AmeriFlux sites, to evaluate the feasibility and merit of developing standardized footprint results. In addition to comparing outcomes from several footprint models, we will attempt to verify and validate the results in two ways: (i) Verification of our footprint calculations at sites where footprints have been experimentally estimated. (ii) Validation at towers situated in heterogeneous landscapes: here, variations in the observed fluxes are expected to correlate with spatiotemporal variations of the source area composition. Once implemented, the footprint results can be used as additional information within the AmeriFlux database that can support data interpretation and data assimilation. Lastly, we will explore the expandability of this approach to other flux networks by collaborating with and including sites from the ICOS and NEON networks in our analyses. This can enable utilizing the footprint model output to improve network interoperability, thus further promoting synthesis analyses and understanding of system-level questions in the future.

  1. Quality-Controlled Wind Data from the Kennedy Space Center 915 Megahertz Doppler Radar Wind Profiler Network

    NASA Technical Reports Server (NTRS)

    Dryden, Rachel L.

    2011-01-01

    The National Aeronautics and Space Administration s (NASA) Kennedy Space Center (KSC) has installed a five-instrument 915-Megahertz (MHz) Doppler Radar Wind Profiler (DRWP) system that records atmospheric wind profile properties. The purpose of these profilers is to fill data gaps between the top of the KSC wind tower network and the lowest measurement altitude of the KSC 50-MHz DRWP. The 915-MHz DRWP system has the capability to generate three-dimensional wind data outputs from approximately 150 meters (m) to 6,000 m at roughly 15-minute (min) intervals. NASA s long-term objective is to combine the 915-MHz and 50-MHz DRWP systems to create complete vertical wind profiles up to 18,300 m to be used in trajectory and loads analyses of space vehicles and by forecasters on day-of-launch (DOL). This analysis utilizes automated and manual quality control (QC) processes to remove erroneous and unrealistic wind data returned by the 915-MHz DRWP system. The percentage of data affected by each individual QC check in the period of record (POR) (i.e., January to April 2006) was computed, demonstrating the variability in the amount of data affected by the QC processes. The number of complete wind profiles available at given altitude thresholds for each profiler in the POR was calculated and outputted graphically, followed by an assessment of the number of complete wind profiles available for any profiler in the POR. A case study is also provided to demonstrate the QC process on a day of a known weather event.

  2. Tower-supported solar-energy collector

    NASA Technical Reports Server (NTRS)

    Selcuk, M. K.

    1977-01-01

    Multiple-collector tower system supports three receiver/concentrators that absorb solar energy reflected from surrounding field of heliostats. System overcomes disadvantages of tower-supported collectors. Booms can be lowered during heavy winds to protect arms and collectors.

  3. SWECS tower dynamics analysis methods and results

    NASA Technical Reports Server (NTRS)

    Wright, A. D.; Sexton, J. H.; Butterfield, C. P.; Thresher, R. M.

    1981-01-01

    Several different tower dynamics analysis methods and computer codes were used to determine the natural frequencies and mode shapes of both guyed and freestanding wind turbine towers. These analysis methods are described and the results for two types of towers, a guyed tower and a freestanding tower, are shown. The advantages and disadvantages in the use of and the accuracy of each method are also described.

  4. Half-hourly atmospheric 13CO2 observed by cavity ring-down spectroscopy analyzer in the USDA Forest Service Climate Tower Network

    NASA Astrophysics Data System (ADS)

    Lai, C.; Hollinger, D. Y.; Massman, W. J.; Clark, K. L.; Bible, K.; Vose, J.; Desai, A. R.; Kolka, R.; Richardson, A. D.; Hom, J. L.; Evans, R.; Forest Service Climate Tower Network

    2011-12-01

    Network-wide measurements of atmospheric 13CO2 enable the partitioning of global CO2 into oceanic and terrestrial sources and sinks by a 'double-deconvolution' approach. The approach is sensitive to small changes in the13C/12C signatures associated with terrestrial photosynthesis (?) and respiration (?13CR). Flask-based measurements have provided robust estimates of terrestrial 13C discrimination at seasonal time scales. These canopy-level 13C observations were in general agreement with our leaf-level understanding of physiological responses to environmental variation, though many relationships remain empirical. An improved temporal resolution of 13C measurements in stress-sensitive ecosystems by a coordinated network would strategically provide much-needed data to further develop mechanistic models for the assessment of continental-scale carbon budget. Here we present high-precision, continuous 13CO2 measurements made by Picarro cavity ring-down spectroscopy instrument at a subset of AmeriFlux towers (Wind River, GLEES, Howland, Silas Little, and Coweeta) in the new USDA Forest Service Climate Tower Network. Most of these sites have long eddy flux and meteorological records and a history of participating in syntheses. Half-hourly average CO2, H2O and 13CO2 mixing ratios have been recorded at 3 canopy heights (1m aboveground, mid- and above-canopy) since 2010. Analyzer-dependent sensitivity to temperature fluctuation, water vapor concentration, and CO2 concentration were carefully evaluated and their performances were compared between the 5 Picarro analyzers. We also compared the self-generated calibration functions with manufacturer specifications. Large discrepancies were noted in some cases, suggesting the need to independently evaluate these still-evolving spectroscopy analyzers by the users. Upon careful calibration, these analyzers were capable of producing continuous 13CO2 data that gave good agreement when compared to flask measurements. Diurnal and vertical profiles of atmospheric 13CO2 measured in the 5 USFS-managed forests are presented and discussed.

  5. Global Network of Slow Solar Wind N. U. Crooker1

    E-print Network

    Zhao, Xuepu

    Global Network of Slow Solar Wind N. U. Crooker1 Center for Space Physics, Boston University of the slow solar wind. Synoptic maps of solar wind speed predicted by the Wang-Sheeley-Arge model during selected periods of solar cycle 23, however, show many areas of slow wind displaced from the streamer belt

  6. Wind Power Plant Prediction by Using Neural Networks: Preprint

    SciTech Connect

    Liu, Z.; Gao, W.; Wan, Y. H.; Muljadi, E.

    2012-08-01

    This paper introduces a method of short-term wind power prediction for a wind power plant by training neural networks based on historical data of wind speed and wind direction. The model proposed is shown to achieve a high accuracy with respect to the measured data.

  7. Assessing and improving the representativeness of monitoring networks: The European flux tower network example

    NASA Astrophysics Data System (ADS)

    Sulkava, Mika; Luyssaert, Sebastiaan; Zaehle, SöNke; Papale, Dario

    2011-09-01

    It is estimated that more than 500 eddy covariance sites are operated globally, providing unique information about carbon and energy exchanges between terrestrial ecosystems and the atmosphere. These sites are often organized in regional networks like CarboEurope-IP, which has evolved over the last 15 years without following a predefined network design. Data collected by these networks are used for a wide range of applications. In this context, the representativeness of the current network is an important aspect to consider in order to correctly interpret the results and to quantify uncertainty. This paper proposes a cluster-based tool for quantitative network design, which was developed in order to suggest the best network for a defined number of sites or to assess the representativeness of an existing network to address the scientific question of interest. The paper illustrates how the tool can be used to assess the performance of the current CarboEurope-IP network and to improve its design. The tool was tested and validated with modeled European GPP data as the target variable and by using an empirical upscaling method (Artificial Neural Network (ANN)) to assess the improvements in the ANN prediction with different design scenarios and for different scientific questions, ranging from a simple average GPP of Europe to spatial, temporal, and spatiotemporal variability. The results show how quantitative network design could improve the predictive capacity of the ANN. However, the analysis also reveals a fundamental shortcoming of optimized networks, namely their poor capacity to represent the spatial variability of the fluxes.

  8. Convection towers

    DOEpatents

    Prueitt, M.L.

    1994-02-08

    Convection towers which are capable of cleaning the pollution from large quantities of air and of generating electricity utilize the evaporation of water sprayed into the towers to create strong airflows and to remove pollution from the air. Turbines in tunnels at the skirt section of the towers generate electricity. Other embodiments may also provide fresh water, and operate in an updraft mode. 5 figures.

  9. KALMAN-FILTER BASED DATA FUSION FOR NEUTRALAXIS TRACKING FOR DAMAGE DETECTION IN WIND-TURBINE TOWERS

    E-print Network

    Boyer, Edmond

    KALMAN-FILTER BASED DATA FUSION FOR NEUTRALAXIS TRACKING FOR DAMAGE DETECTION IN WIND-TURBINE Monitoring, Strain Sensors, Wind Turbine, Neutral Axis tracking, Kalman Filter INTRODUCTION Ever since to the advancements in the field of materials engineering and manufacturing methods. Newer, bigger wind turbines which

  10. Variation in bat and bird fatalities at wind energy facilities: assessing the effects of rotor size and tower height

    Microsoft Academic Search

    Robert M. R. Barclay; E. F. Baerwald; J. C. Gruver

    2007-01-01

    Wind energy is a rapidly growing sector of the alternative energy industry in North America, and larger, more productive turbines are being installed. However, there are concerns regarding bird and bat fatalities at wind turbines. To assess the influence of turbine size on bird and bat fatalities, we analyzed data from North American wind energy facili- ties. Diameter of the

  11. Balsa Towers

    NSDL National Science Digital Library

    Techtronics Program,

    Students groups use balsa wood and glue to build their own towers using some of the techniques they learned from the associated lesson. While general guidelines are provided, give students freedom with their designs and encourage them to implement what they have learned about structural engineering. The winning team design is the tower with the highest strength-to-weight ratio.

  12. Devils Tower

    USGS Multimedia Gallery

    Devils Tower is a laccolith in the Black Hills of Wyoming. A laccolith forms when molten magma forces its way into a rock formation, then cools and hardens. As the surrounding rock erodes away, the hardened former magma remains....

  13. Coit Tower

    NSDL National Science Digital Library

    Bisson, Mimi.

    Located on top of Telegraph Hill, Coit Tower was the result of a significant donation by Lillie Coit in the 1920s and the ingenuity of the New Deal program initiated by President Franklin Delano Roosevelt. When Lillie Coit passed away in 1929, she left substantial donations to a number of institutions, including the city and county of San Francisco. Shortly after this gift, plans were made to create a memorial to Coit on Telegraph Hill in the form of a single elegant tower. Of course, when the structure was finished, it was largely unadorned on the inside. This situation was soon changed, as a number of artists employed under the auspices of the Public Works Art Project began to work on a number of lovely frescoes depicting scenes from California history. On this site, visitors can learn about the history of Coit Tower, and also view the remarkable works of art that are located within the structure.

  14. Reducing Wind Tunnel Data Requirements Using Neural Networks

    NASA Technical Reports Server (NTRS)

    Ross, James C.; Jorgenson, Charles C.; Norgaard, Magnus

    1997-01-01

    The use of neural networks to minimize the amount of data required to completely define the aerodynamic performance of a wind tunnel model is examined. The accuracy requirements for commercial wind tunnel test data are very severe and are difficult to reproduce using neural networks. For the current work, multiple input, single output networks were trained using a Levenberg-Marquardt algorithm for each of the aerodynamic coefficients. When applied to the aerodynamics of a 55% scale model of a U.S. Air Force/ NASA generic fighter configuration, this scheme provided accurate models of the lift, drag, and pitching-moment coefficients. Using only 50% of the data acquired during, the wind tunnel test, the trained neural network had a predictive accuracy equal to or better than the accuracy of the experimental measurements.

  15. Tokyo Tower

    E-print Network

    Hacker, Randi; Tsutsui, William; Ashworth, William

    2007-01-03

    with a certain pop celebrity cach?: Godzilla destroyed it in one film, Mothra used it as a nest in another, and the psychic Uri Geller once bounced telekinetic rays off it to bend spoons and fix broken clocks all over Tokyo. Who knows what else the Tower...

  16. Experimental investigation of the dynamic installation of a slip joint connection between the monopile and tower of an offshore wind turbine

    NASA Astrophysics Data System (ADS)

    Segeren, M. L. A.; Hermans, K. W.

    2014-06-01

    The failure of the traditional grouted connections of offshore wind turbines has led to the investigation of alternatives that provide a connection between the foundation pile and the turbine tower. An alternative to the traditional joint is a steel-to-steel connection also called a slip joint. To ensure a proper fit of the slip joint a dynamic installation of the joint is proposed. In this contribution, the effectiveness of harmonic excitation as an installation procedure is experimentally investigated using a 1:10 scaled model of the joint. During the dynamic installation test the applied static load, settlements and dynamic response of the joint are monitored using respectively load cells, taut wires and strain gauges placed both inside and outside the conical surfaces. The results show that settlement occurs only when applying a harmonic load at specific forcing frequencies. The settlement stabilizes to a certain level for each of the specific frequencies, indicating that a controlled way of installation is possible. The results show that it is essential to vibrate at specific frequencies and that a larger amplitude of the harmonic force does not automatically lead to additional settlement.

  17. Performance of cool towers under various climates in Jordan

    Microsoft Academic Search

    Ali A Badran

    2003-01-01

    The concept of cool towers, which is a modern version of the historical wind catchers was re-visited. In contrast with the expression of cooling towers, which usually refers to equipment used to cool the water in power stations, air conditioning plants etc., cool towers are used to cool the air to provide comfort conditions for occupants. The main driving force

  18. Surface and Tower Meteorological Instrumentation at NSA Handbook - January 2006

    SciTech Connect

    MT Ritsche

    2006-01-30

    The Surface and Tower Meteorological Instrumentation at Atqasuk (METTWR2H) uses mainly conventional in situ sensors to measure wind speed, wind direction, air temperature, dew point and humidity mounted on a 10-m tower. It also obtains barometric pressure, visibility, and precipitation data from sensors at or near the base of the tower. In addition, a Chilled Mirror Hygrometer is located at 1 m for comparison purposes. Temperature and relative humidity probes are mounted at 2 m and 5 m on the tower. For more information, see the Surface and Tower Meteorological Instrumentation at Atqasuk Handbook.

  19. Virtual Tower

    SciTech Connect

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

    1997-08-01

    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.

  20. Evapotranspiration and energy flux observations from a global tower network with a critical analysis of uncertainties

    NASA Astrophysics Data System (ADS)

    Stoy, P. C.

    2012-12-01

    Eddy covariance studies tend to focus on the flux of carbon dioxide despite the central role of surface-atmosphere water and energy exchange in the climate system. The under-utilization of water and energy flux data is due in part to uncertainties, including the lack of observed energy balance closure. Across 173 FLUXNET sites, energy balance closure averaged 0.84 with best average closure in evergreen broadleaf forests and savannas (0.91-0.94) and worst average closure in crops, deciduous broadleaf forests, mixed forests and wetlands (0.70-0.78). The simplest explanatory model using information criteria analyses cannot exclude landscape-level heterogeneity. This finding is in empirical agreement with studies that suggest that secondary circulations, likely attributable to landscape-scale variability, are related to lack of energy balance closure, although unmeasured storage terms cannot be ruled out as a dominant contributor. Keeping uncertainties in mind, evapotranspiration and sensible heat flux follow expected seasonal patterns, and the magnitude of evapotranspiration in temperate ecosystems approached that of tropical ecosystems during the peak growing season. Latent heat exchange is constrained by an exponentially-decreasing function of vapor pressure deficit, consistent with theories of optimal stomatal behavior. Forests tended to have cooler surface temperatures when controlled for net radiation than did short-statured ecosystems, and further investigations revealed the importance of efficient heat and water vapor transport in forest canopies that are well-coupled to the atmosphere. The value of energy and water flux data from FLUXNET increases as uncertainties become better-understood, and careful interpretations of tower-level water and energy flux data will ultimately improve our understanding of the role of terrestrial ecosystems in the Earth system.

  1. 'Towers in the Tempest' Computer Animation Submission

    NASA Technical Reports Server (NTRS)

    Shirah, Greg

    2008-01-01

    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.

  2. Improvement of Offshore Wind Resource Modeling in the Mid-

    E-print Network

    Firestone, Jeremy

    Interaction Tower ­ 23 m NOAA Buzzard's Bay Tower ­ 25 m Cape Wind Tower (60 m from 2003-2011; just platform at height ·Restoration of Cape Wind facility ·Instrumentation of other existing towers, like ASITImprovement of Offshore Wind Resource Modeling in the Mid- Atlantic Bight Wind Energy Symposium

  3. 2004 Savannah River Cooling Tower Collection (U)

    SciTech Connect

    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)

    2005-05-01

    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.

  4. Upward lightning observations from towers in Rapid City, South Dakota and comparison with National Lightning Detection Network data, 2004-2010

    NASA Astrophysics Data System (ADS)

    Warner, Tom A.; Cummins, Kenneth L.; Orville, Richard E.

    2012-10-01

    We report on upward lightning observations from ten tall towers (91-191 m) in Rapid City, South Dakota, USA and compare with National Lightning Detection Network (NLDN) data. A total of 81 upward flashes were observed from 2004-2010 using GPS time-stamped optical sensors, and in all but one case, visible flash activity preceded the development of the upward leaders. Time-correlated analysis showed that the NLDN recorded an event within 50 km of towers and within 500 ms prior to upward leader development from the tower(s) for 83% (67/81) of the upward flashes. A preceding positive cloud-to-ground stroke (+CG) was detected in 57% (46/81) of the cases, and a preceding positive intracloud flash (+IC) in 23% (19/81) of the cases. However, 8 of the 19 NLDN-indicated +IC events were actually +CG strokes based on optical observations. Preceding negative intracloud flashes (-IC) were recorded for 2% (2/81) of the cases. Analysis also showed that for 44% (36/81) of the upward flashes, the NLDN reported subsequent negative cloud-to-ground (-CG) strokes and/or -IC events at one or more tower locations. Of the 151 subsequent events, 70% (105/151) were -CG reports and 30% (46/151) were listed as -IC events. The geometric mean/median location accuracy and peak current for subsequent events were 194 m/206 m and -12.9 kA/-12.4 kA respectively. These correlated observations suggest that a majority of the upward lightning flashes were triggered by a preceding flash with the dominant triggering type being the +CG flash.

  5. Nocturnal wind direction shear and its potential impact on pollutant transport

    SciTech Connect

    Bowen, B.M.; Baars, J.A.; Stone, G.L.

    1997-09-01

    The estimation of transport and diffusion of airborne pollutants during the nighttime is challenging, especially over complex terrain where gravity driven drainage flows may be overlain with wind from a different direction. This study investigates the character of wind direction shear in the lowest 100 m using tower measurements from a complex, semi-arid site where local thermally-driven flows are common. the effects of wind direction shear on plume transport are studied by simulating a hypothetical elevated term release. This is accomplished by first simulating transport and dispersion using wind measurements from only the 12-m level from a network of towers. This case represents the approach commonly taken at many facilities where a network of short towers is available. Then the release is modeled using wind measurements made at four levels in the lowest 100 m. The differences between the two simulations are significant and would lead to very different responses in an emergency situation.

  6. Optimizing the Design of a Wind Farm Collection Network

    E-print Network

    Hertz, Alain

    produced through eco-friendly means, such as wind turbines or solar panels. In this article we study of collecting the energy produced by the turbines and sending it to a known sub-station. The network building costs, are known. Each type of link (UG cable or transmission line) has a limited capacity. Also

  7. WIND TURBINE CONNECTED TO THE ELECTRICAL NETWORK

    Microsoft Academic Search

    SYNCHRONOUS POWER

    He brings forth the wind from His storehouses. Psalms 135:7 Only a few hardy people in the United States live where 60 Hz utility power is not readily available. The rest of us have grown accustomed to this type of power. The utility supplies us reliable power when we need it, and also maintains the transmission and distribution lines and

  8. Devil's Tower Geology

    NSDL National Science Digital Library

    National Park Service (NPS)

    This site from the National Park Service briefly addresses the geology of Devil's Tower. The evolution of various theories on the formation of the tower are discussed. A slide show of the emplacement of the tower is also available.

  9. Design of a Wind Power Generation Monitoring System Based on Wireless Sensor Network

    Microsoft Academic Search

    Li Lin; Shen Ming-xia

    2010-01-01

    Wind energy is one kind of purity, non-polluting, renewable new energy. Real-time monitoring wind power generation system is an important action bearing with steady operation of system and high efficiency exploiting wind power resources. A novel intelligent monitoring system plan for wind power generation based on wireless sensor networks is proposed in this paper, which employs many high technologies such

  10. Ocean breeze monitoring network at the Oyster Creek Nuclear Plant

    SciTech Connect

    Heck, W.

    1987-01-01

    The Oyster Creek Nuclear Generating Station (OCNGS) is located in New Jersey 10 km west of the Atlantic Ocean. Routine meteorological monitoring at the station has consisted of a single meteorological tower 120 m high and instrumented at the 10-m, 46-m, and 116-m levels. An analysis of 5 yr of data from this tower showed the OCNGS is affected by an ocean breeze approx. 1 day out of 4 during May through August. This suggested the need for meteorological monitoring in addition to the single met tower at OCNGS. As a result of the 1985 OCNGS meteorological monitoring study, GPU Nuclear established an ocean breeze monitoring network in the fall of 1986. It is a permanent part of OCNGS meteorological monitoring and consists of the same sites as used in the 1985 field study. Meteorological towers are located at the ocean site, the inland site, and at OCNGS. The ocean tower is 13 m (43 ft) high, the inland tower 10 m (33 ft), and the OCNGS tower 116 m (380 ft). Wind speed, wind direction, and temperature are measured on each tower; delta-temperature is also measured on the main tower. The instruments are calibrated in the spring, summer, and fall. The network is operated and maintained by GPU Nuclear Environmental Controls. The ocean breeze monitoring network and meteorological information system forms the basis for including the effects of the ocean breeze in OCNGS emergency off-site dose assessment.

  11. Recommendations for a wind profiling network to support Space Shuttle launches

    NASA Technical Reports Server (NTRS)

    Zamora, R. J.

    1992-01-01

    The feasibility is examined of a network of clear air radar wind profilers to forecast wind conditions before Space Shuttle launches during winter. Currently, winds are measured only in the vicinity of the shuttle launch site and wind loads on the launch vehicle are estimated using these measurements. Wind conditions upstream of the Cape are not monitored. Since large changes in the wind shear profile can be associated with weather systems moving over the Cape, it may be possible to improve wind forecasts over the launch site if wind measurements are made upstream. A radar wind profiling system is in use at the Space Shuttle launch site. This system can monitor the wind profile continuously. The existing profiler could be combined with a number of radars located upstream of the launch site. Thus, continuous wind measurements would be available upstream and at the Cape. NASA-Marshall representatives have set the requirements for radar wind profiling network. The minimum vertical resolution of the network must be set so that the wind shears over the depths greater than or = 1 km will be detected. The network should allow scientists and engineers to predict the wind profile over the Cape 6 hours before a Space Shuttle launch.

  12. Experimental study of effects of separation distance between twin high-rise tower models on gaseous diffusion behind the downwind tower model

    Microsoft Academic Search

    Masaaki Ohba

    1998-01-01

    Twin high-structures give rise to the additional complexity of a nearby structure. The separation distances between twin high-rise towers have especially large effects on the flow and the concentration fields around them. Wind tunnel experiments have shown that the primary effect of the upwind tower is to retard the flow separation on the top and sides of the downwind tower,

  13. Towers for Earth Launch

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A.; Lyons, Valerie J. (Technical Monitor)

    2002-01-01

    This report lists some characteristics of a hypothetical 15 kilometer tower for launching spacecraft, the advantages of launching from high altitude, and some equations pertaining to launch from a 15 kilometer tower.

  14. Aerodynamic tower shake force analysis for VAWT

    SciTech Connect

    Loth, J.L.

    1985-02-01

    Vertical axis wind turbines (VAWT) are subjected to blade lift forces which vary continuously in both magnitude and direction. These blade lift forces are transmitted via the blade support arms to the tower. The resulting tower force vector is a composite of: a downwind and a crosswind average force component, rotating force vectors, and force vectors oscillating in the crosswind direction. The frequency of the rotating and oscillating forces are multiples of the product of Bw, where B is the number of blades used and ..omega.. is the rotor angular velocity. The magnitude of the largest tower shake force vector is of the same order as the average downwind force component, and may represent a serious design constraint in the calculation of the required tower stiffness. A closed-form solution for the tower force vectors has been derived, by introducing a suitable wind interference model. It shows that the magnitude of the largest tower shake force vector, using a threebladed rotor, is four times smaller than a two-bladed rotor. The Betz limit and the optimum tip speed ratio as a function of solidity has been derived by comparison with two semicylindrical actuators in series.

  15. Cooling tower reconstruction

    Microsoft Academic Search

    A. A. Sukhov; A. G. Venzhega; V. N. Beizer; A. V. Kovalenko

    1983-01-01

    At the majority of coking plants the primary gas cooler water cooling cycle uses cooling towers with natural tower draft. The Yasinovka Coke Works installed three such cooling towers with capacity of 1000 m³\\/hr of water each with irrigation surface of 1000 m². The water distribution is gravity-flow, unpressurized. The construction of one cooling tower consumes 610 m³ of lumber.

  16. Exploiting inertia of wind turbines in power network frequency control: A model predictive control approach

    Microsoft Academic Search

    N. P. G. van Deelen; A. Jokic; P. P. J. van den Bosch; R. M. Hermans

    2011-01-01

    With the expected increase in penetration level of wind turbine generators in the near future, it will be necessary for them to participate in power network frequency control. In this paper we exploit the inertia of wind turbine generators us- ing model predictive control (MPC). In this way wind turbines can actively contribute to primary control. Safe operation is possible

  17. A numerical study of interacting buoyant cooling-tower plumes

    Microsoft Academic Search

    R. B. Bornoff; M. R. Mokhtarzadeh-Dehghan

    2001-01-01

    The compact design of mechanical cooling towers necessitates that the plumes are issued into the cross-wind in close proximity. An improved understanding of the interaction of adjacent plumes is therefore required for better design of such cooling towers, which may lead to a reduction in their environmental impact. This paper presents the results of a numerical investigation into the interaction

  18. System stability of large wind power networks: A Danish study case

    Microsoft Academic Search

    Vladislav Akhmatov

    2006-01-01

    The article describes the considerations and the results of the investigation on short-term voltage stability carried out on a large wind power network model that is similar to a part of the Danish power grid. In the investigated power network, around 50% of the electricity consumption is covered by wind turbines and local combined heat and power (CHP) units. A

  19. Application of Neural Networks to Wind tunnel Data Response Surface Methods

    NASA Technical Reports Server (NTRS)

    Lo, Ching F.; Zhao, J. L.; DeLoach, Richard

    2000-01-01

    The integration of nonlinear neural network methods with conventional linear regression techniques is demonstrated for representative wind tunnel force balance data modeling. This work was motivated by a desire to formulate precision intervals for response surfaces produced by neural networks. Applications are demonstrated for representative wind tunnel data acquired at NASA Langley Research Center and the Arnold Engineering Development Center in Tullahoma, TN.

  20. Beneath the shadow of the Tower Soldiers' Tower

    E-print Network

    Beneath the shadow of the Tower Soldiers' Tower Schedule of Events October-November 2013 As of Oct. 21, 2013 Telephone: 416-978-3485 (office) E-mail: soldiers.tower@utoronto.ca Soldiers' Tower Web Site: www.alumni.utoronto.ca/tower Facebook: www.facebook.com/soldierstower U of T Events web site: www

  1. Variation characteristics of regional synchronous wind in Hami, Xinjiang of Northwest China

    NASA Astrophysics Data System (ADS)

    Huang, Linhong; Song, Lili; Li, Gang; Xin, Yu

    2015-04-01

    From several towers in Hami, Xinjiang of Northwest China, built by the national wind power resources professional observation network, we selected three towers with synchronous 10-min average wind speed data for one year (May 2011-April 2012) under strict quality control. The towers are located where large-scale wind power development is projected. We analyzed the frequency and variation of extreme wind speed at low wind condition (LWC), rated wind condition (RWC), and cut-out wind condition (CWC), which may significantly impact the electric power grid configuration in large-scale wind power development. The correlation between duration and frequency of LWC/RWC/CWC is obtained. Major findings are: 1) The frequency of CWC is the lowest among all conditions, its synchronous rate at all three towers tends to be zero, and the frequency of LWC is always greater than that of RWC. 2) Among the three towers, the synchronous rate of RWC steadily increases with height, and LWC differs little between different levels. The synchronous rate of LWC concentrates in winter, while that of RWC mainly occurs in spring and summer. Diurnal variation of LWC/RWC during the entire year is significantly different. 3) During the study year, the longest durations of synchronous LWC and RWC among the three towers are up to 640 and 700 min, respectively. The duration and frequency of LWC/RWC can be quantitatively well described by a logarithmic function. Consequently, the synchronous rates of LWC and RWC over any duration in the region can be easily calculated by using the fitting function equation from observed data. These results are of value to the planning of large-scale wind power transmission and grid dispatching in this area.

  2. WindTalker: A P2P-Based Low-Latency Anonymous Communication Network

    NASA Astrophysics Data System (ADS)

    Zhang, Jia; Duan, Haixin; Liu, Wu; Wu, Jianping

    Compared with traditional static anonymous communication networks, the P2P architecture can provide higher anonymity in communication. However, the P2P architecture also leads to more challenges, such as route, stability, trust and so on. In this paper, we present WindTalker, a P2P-based low-latency anonymous communication network. It is a pure decentralized mix network and can provide low-latency services which help users hide their real identity in communication. In order to ensure stability and reliability, WindTalker imports “seed nodes” to help a peer join in the P2P network and the peer nodes can use gossip-based protocol to exchange active information. Moreover, WindTalker uses layer encryption to ensure the information of relayed messages cannot be leaked. In addition, malicious nodes in the network are the major threat to anonymity of P2P anonymous communication, so WindTalker imports a trust mechanism which can help the P2P network exclude malicious nodes and optimize the strategy of peer discovery, tunnel construction, and relaying etc. in anonymous communications. We deploy peer nodes of WindTalker in our campus network to test reliability and analyze anonymity in theory. The network measurement and simulation analysis shows that WindTalker can provide low-latency and reliable anonymous communication services.

  3. Electricity meters for coordinated voltage control in medium voltage networks with wind power

    Microsoft Academic Search

    Ingmar Leisse; Olof Samuelsson; Jörgen Svensson

    2010-01-01

    During the last years the amount of electricity generated by Distributed Energy Resources (DER), especially wind turbines, has been increasing a lot. These Distributed Generation (DG) units are often connected to rural distribution networks, where they have a large impact on the voltage and the network losses. The network voltage at the customers point of connection is an important quality

  4. Cooling Towers, The Debottleneckers 

    E-print Network

    Burger, R.

    1998-01-01

    COOLING TOWERS, THE DEBOITLENECKERS by Robert Burger, Consultant The Burger Cooling Tower Company Dallas, Texas 75234 INTRODUCTION Power generating pl:mts :md petro-chemical works are always expanding. An on-going problem is to identify..., George, Munters Corp. "Cellular Tower Fill" CTI paper TP-67-0 I, 1967 Annual Meeting. [4] Phelps Patent 4,007,241 February 8, 1977. [5] MarJey Bulletin SB-9 5.92. [6] Burger, Robert, "Cooling Tower Technology" Textbook. Jrd edition, 1994 Chapter 6...

  5. Structural Monitoring of Wind Turbines using Wireless Sensor Networks

    E-print Network

    Lynch, Jerome P.

    becomes more critical. Wind power has tremendous potential to provide renewable energy without reliance developed and practical alternative today. Recent studies put the annual wind energy generation capacity from wind (Wiser and Bolinger 2007). By substantially increasing its wind power capacity, the United

  6. Surface and Tower Meteorological Instrumentation at Atqasuk (METTWR2H) Handbook

    SciTech Connect

    Ritsche, MT

    2006-01-01

    The Atqasuk meteorology station (AMET) uses mainly conventional in situ sensors to measure wind speed, wind direction, air temperature, dew point, and humidity mounted on a 10-m tower. It also obtains barometric pressure, visibility and precipitation data from sensors at or near the base of the tower. In addition, a chilled mirror hygrometer (CMH) is located at 1 m for comparison purposes. Temperature and relative humidity (RH) probes are mounted at 2 m and 5 m on the tower.

  7. 18. NORTH TOWER, PORTE COCHERE & FLAG TOWER, LOOKING SOUTHWEST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. NORTH TOWER, PORTE COCHERE & FLAG TOWER, LOOKING SOUTHWEST BY WEST - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  8. 19. NORTH TOWER, PORTE COCHERE & FLAG TOWER, LOOKING SOUTHWEST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. NORTH TOWER, PORTE COCHERE & FLAG TOWER, LOOKING SOUTHWEST - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  9. 36. FLAG TOWER CLOCK ZONE FROM SOUTH TOWER ROOF, LOOKING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    36. FLAG TOWER CLOCK ZONE FROM SOUTH TOWER ROOF, LOOKING NORTH - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  10. 40. CAMPANILE & SOUTHEAST TOWER FROM SOUTH TOWER ROOF, LOOKING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    40. CAMPANILE & SOUTHEAST TOWER FROM SOUTH TOWER ROOF, LOOKING EAST BY NORTHEAST - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  11. 43. TOP OF SOUTHEAST TOWER FROM SOUTH TOWER ROOF, LOOKING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    43. TOP OF SOUTHEAST TOWER FROM SOUTH TOWER ROOF, LOOKING EAST - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  12. 37. NORTH TOWER UPPER ZONE FROM SOUTH TOWER ROOF, LOOKING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    37. NORTH TOWER UPPER ZONE FROM SOUTH TOWER ROOF, LOOKING NORTH - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  13. 47. NORTHWEST TOWER FROM SOUTH TOWER ROOF, LOOKING NORTH BY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    47. NORTHWEST TOWER FROM SOUTH TOWER ROOF, LOOKING NORTH BY NORTHWEST - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  14. Estimation of mesoscale thermospheric wind structure using a network of interferometers

    NASA Astrophysics Data System (ADS)

    Harding, Brian J.; Makela, Jonathan J.; Meriwether, John W.

    2015-05-01

    We introduce a technique for estimating the regional thermospheric wind field from measurements made by a network of interferometers. Unlike previous work, this technique does not make assumptions about the functional form of the wind field and instead uses inverse theory to find the smoothest wind field that agrees with the measurements. This technique is general and applies to any network making radial velocity measurements. We show reconstructions of the thermospheric wind field over the eastern United States and over eastern Brazil, using data from two distinct networks of Fabry-Perot interferometers measuring the Doppler shift of the 630.0 nm airglow emission. In Brazil, we find direct evidence of a convergent wind field during the period of rapid thermospheric temperature increase associated with the equatorial midnight temperature maximum.

  15. Vice President CEO, Tower Foundation

    E-print Network

    Su, Xiao

    Vice President CEO, Tower Foundation Administrative Assistant to the AVP Information Representative Tower Foundation Charitable Gifts Officer Gift Analyst Gift Analyst Gift Analyst Senior Analyst Tower Foundation Stewardship Director Graphic Designer Administrative Assistant Web Communications

  16. Wind

    NSDL National Science Digital Library

    National Energy Education Development (NEED) Project

    2003-01-01

    This document examine wind power as an energy resource. The reading will define wind and discuss topics such as (1) The history of wind machines, (2) Today's windmills, and (3) Types of wind machines. This resource is structured as an informational handout to supplement your energy activities or to generate discussion questions. Copyright 2005 International Technology Education Association

  17. 76 FR 10328 - Grant of Authority for Subzone Status; Vestas Nacelles America, Inc. (Wind Turbine Nacelles, Hubs...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-24

    ...Vestas Nacelles America, Inc. (Wind Turbine Nacelles, Hubs, Blades and Towers...special-purpose subzone at the wind turbine nacelle, hub, blade and tower...manufacturing and warehousing of wind turbine nacelles, hubs, blades and...

  18. Flexible dynamics of floating wind turbines

    E-print Network

    Luypaert, Thomas (Thomas J.)

    2012-01-01

    This work presents Tower Flex, a structural dynamics model for a coupled analysis of offshore floating wind turbines consisting of a tower, a floating platform and a mooring system. In this multi-body, linear frequency-domain ...

  19. Confusion at the Tower

    ERIC Educational Resources Information Center

    Li, Loretta F.

    2014-01-01

    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…

  20. Lost Subways: Tower Hill

    NSDL National Science Digital Library

    Delaitre, Frederic

    This interesting website reviews "lost subways," including photos, articles, and other historical information. The Tower Hill Subway was England's first tube railway under the Thames which was open for public use from 1870-1896. This page offers an overview, timeline, history, description of the tunnel (in French), a bibliography, and a list of online resources about the Tower Hill Subway.

  1. Coastal Ohio Wind Project

    SciTech Connect

    Gorsevski, Peter; Afjeh, Abdollah; Jamali, Mohsin; Bingman, Verner

    2014-04-04

    The Coastal Ohio Wind Project intends to address problems that impede deployment of wind turbines in the coastal and offshore regions of Northern Ohio. The project evaluates different wind turbine designs and the potential impact of offshore turbines on migratory and resident birds by developing multidisciplinary research, which involves wildlife biology, electrical and mechanical engineering, and geospatial science. Firstly, the project conducts cost and performance studies of two- and three-blade wind turbines using a turbine design suited for the Great Lakes. The numerical studies comprised an analysis and evaluation of the annual energy production of two- and three-blade wind turbines to determine the levelized cost of energy. This task also involved wind tunnel studies of model wind turbines to quantify the wake flow field of upwind and downwind wind turbine-tower arrangements. The experimental work included a study of a scaled model of an offshore wind turbine platform in a water tunnel. The levelized cost of energy work consisted of the development and application of a cost model to predict the cost of energy produced by a wind turbine system placed offshore. The analysis found that a floating two-blade wind turbine presents the most cost effective alternative for the Great Lakes. The load effects studies showed that the two-blade wind turbine model experiences less torque under all IEC Standard design load cases considered. Other load effects did not show this trend and depending on the design load cases, the two-bladed wind turbine showed higher or lower load effects. The experimental studies of the wake were conducted using smoke flow visualization and hot wire anemometry. Flow visualization studies showed that in the downwind turbine configuration the wake flow was insensitive to the presence of the blade and was very similar to that of the tower alone. On the other hand, in the upwind turbine configuration, increasing the rotor blade angle of attack reduced the wake size and enhanced the vortices in the flow downstream of the turbine-tower compared with the tower alone case. Mean and rms velocity distributions from hot wire anemometer data confirmed that in a downwind configuration, the wake of the tower dominates the flow, thus the flow fields of a tower alone and tower-turbine combinations are nearly the same. For the upwind configuration, the mean velocity shows a narrowing of the wake compared with the tower alone case. The downwind configuration wake persisted longer than that of an upwind configuration; however, it was not possible to quantify this difference because of the size limitation of the wind tunnel downstream of the test section. The water tunnel studies demonstrated that the scale model studies could be used to adequately produce accurate motions to model the motions of a wind turbine platform subject to large waves. It was found that the important factors that affect the platform is whether the platform is submerged or surface piercing. In the former, the loads on the platform will be relatively reduced whereas in the latter case, the structure pierces the wave free surface and gains stiffness and stability. The other important element that affects the movement of the platform is depth of the sea in which the wind turbine will be installed. Furthermore, the wildlife biology component evaluated migratory patterns by different monitoring systems consisting of marine radar, thermal IR camera and acoustic recorders. The types of radar used in the project are weather surveillance radar and marine radar. The weather surveillance radar (1988 Doppler), also known as Next Generation Radar (NEXRAD), provides a network of weather stations in the US. Data generated from this network were used to understand general migratory patterns, migratory stopover habitats, and other patterns caused by the effects of weather conditions. At a local scale our marine radar was used to complement the datasets from NEXRAD and to collect additional monitoring parameters such as passage rates, flight paths, flight directi

  2. Wind energy prediction using a two-hidden layer neural network

    Microsoft Academic Search

    Giuseppe Grassi; Pietro Vecchio

    2010-01-01

    The power generated by wind turbines changes rapidly because of the continuous fluctuation of wind speed and air density. As a consequence, it can be important to predict the energy production, starting from some basic input parameters. The aim of this paper is to show that a two-hidden layer neural network can represent a useful tool to carefully predict the

  3. THE ARM WIND PROFILER NETWORK EVALUATION OF PAST PERFORMANCE, THE NEW SAMPLING STRATEGY AND FUTURE

    E-print Network

    THE ARM WIND PROFILER NETWORK ­ EVALUATION OF PAST PERFORMANCE, THE NEW SAMPLING STRATEGY Laboratory For presentation at the Atmospheric Radiation Measurement (ARM) Program Science Team Meeting Brookhaven National Laboratory P.O. Box, Upton, NY www.bnl.gov ABSTRACT The ARM Program operates several wind

  4. Concept study and validation of Antarctic telescope tower

    NASA Astrophysics Data System (ADS)

    Lanford, Ephraim; Swain, Mark; Meyers, Catherine; Muramatsu, Tamao; Nielson, Greg; Olson, Valerie; Ronsse, Sebastien; Vinding Nyden, Emily; Hammerschlag, Robert; Little, Patrick

    2006-06-01

    Studies by Mark Swain and a colleague at the Max Planck Institut fur Astronomie, coupled with results from past and ongoing projects at Harvey Mudd College, strongly suggest that it may be possible to achieve imaging performance comparable to the Hubble Space Telescope at relatively low cost using available, commercial products. This is achievable by placing a 2.4 m telescope, with readily available adaptive optics, on a 30 m tower located at a high-elevation geological "dome" in Antarctica. An initial project surveyed relevant tower design approaches, then generated and evaluated six concept designs for telescope towers. Using data for typical and extreme wind at Dome C to generate wind loads, finite element analysis yielded lateral deflections at the top of 0.3 mm for typical winds and 12.1 mm for extreme gusts, with the lowest resonant frequency at 0.7 Hz; some tower concepts are innovative and allow for easy shipment, setup, and relocation. A subsequent project analyzed a tower designed by Hammerschlag and found fundamental resonance frequencies at 4.3 Hz for bending and 5.9 Hz for torsion; this project also designed and simulated an active telescope control system that maintained 17 milliarcsecond pointing error for the telescope atop the tower during typical wind conditions.

  5. FIELD INVESTIGATION OF COOLING TOWER AND COOLING POND PLUMES

    EPA Science Inventory

    Measurements were made relating to the behavior of water-vapor plumes from forced-draft cooling towers and from cooling ponds. There were three categories of measurements. (1) Ambient weather data including temperature, humidity, wind speed and wind direction. These measurements ...

  6. Characterizing the Vertical Flux of CO2 within the Nocturnal Boundary Layer near a Tall Tower

    NASA Astrophysics Data System (ADS)

    Werth, D. W.; Buckley, R.; Kurzeja, R.; Zhang, G.; Parker, M.; Duarte, H.; Leclerc, M.

    2012-12-01

    Understanding the vertical dispersion of carbon dioxide respired from plants at night is crucial to distinguishing local- to regional-scale transport and continental-scale transport in global carbon budgets. When atmospheric conditions are stable, CO2 will be weakly mixed, and nearby detectors above the surface layer will instead sample CO2 carried from large distances. These conditions often prevail during the nighttime, making that period ideal for continental-scale sampling. On the other hand, during periods of moderate or intermittent nocturnal turbulence, locally-respired CO2 will be transported through the surface layer and produce a signal at the detector. In August 2008, a 329m tall TV tower (33.4058N, 81.834W) in Aiken, South Carolina (the "South Carolina Tower" http://www.esrl.noaa.gov/gmd/ccgg/towers/#sct) was incorporated into the NOAA-Global Monitoring Division's Tall Tower network. This site is located within a region that varies from agricultural, broken forests, suburban, urban and industrial. Emissions from several cities (most notably Augusta, GA) and industrial sites are within 50km of the tower and may contribute disproportionately to the nighttime tower readings. To distinguish local and regional sources, it is necessary to characterize vertical turbulent transport at this site. There are several ways to do this, and we focus on three. First, a mesoscale model was run at high-resolution to recreate the winds and temperature observed during a May 2009 nocturnal tracer release field project conducted in the region surrounding the site. The model data then served as input to a Lagrangian transport model. This was done for two eight-hour periods on successive but different nights: one slightly stable, and the other more stable. The coupled mesoscale/transport model was then validated against the tracer data, and was used to calculate the dispersion properties of the tracer and provide a 3-dimensional picture of the plume. For comparison, we apply two other methods to calculate eddy diffusivity. We calculate it directly using sonic anemometer and fast-response CO2 flux and concentration data from the tall tower. The fast response data (10Hz) allows for the explicit calculation of the turbulent transport and, along with the vertical gradient, provide an estimate of the diffusivity. As a third method, the eddy diffusivity can also be calculated by an empirical method that uses as input the turbulent properties measured at the tower. We select one such method and compare the results to the other two estimates.

  7. Development of Meteorological Towers Using Advanced Composite Materials

    NASA Astrophysics Data System (ADS)

    Alshurafa, Sami A.

    The research program involved both numerical and experimental work. The numerical analysis was conducted to simulate the static and dynamic behaviour of the 81 m meteorological FRP guyed tower under wind and ice loading. The FRP tower consisted of 16 segments each made of 3 cells connected together to form an equilateral triangle having equal sides of 450 mm. The segments were interconnected using internal sleeves. Various non-linear finite element models were developed to study a number of design parameters for the 81 m FRP tower such as, different laminates containing a variety of stacking sequences of laminate orientations with various thicknesses, different cable diameters, and appropriate guy cable spacing levels. The effect of pre-stressing the guy cables up to 10 % of their breaking strength was investigated. The effect of fibre volume fraction on the design of the FRP tower was also examined. Furthermore, an 8.6 m FRP tower segment was designed using the finite element analysis and subject to the same loading conditions experienced by the bottom section of the 81 m FRP tower. A modal analysis was carried out for both the 8.6 m FRP tower segment with and without a mass on the top as well as for the 81 m FRP guyed tower to evaluate the vibration performance of these towers. The experimental work involved extensive material testing to define the material properties for use in the analysis of the 81 m FRP tower. It also involved the design and fabrication of a special collapsible mandrel for fabricating the FRP cells for the 8.6 m tower segment. The 8.6 m tower was tested horizontally under static lateral loading to 80 % of its estimated failure load using a "whiffle tree" arrangement, in order to simulate a uniformly distributed wind loading. Later, the same FRP tower was erected in a vertical position and was tested with and without a mass on top under dynamic loading to obtain the natural frequencies. Lastly, a comparative study was conducted between two 81 m FRP towers having different fibre volume fractions and a steel tower having a circular cross section.

  8. Coupled dynamics analysis of wind energy systems

    NASA Technical Reports Server (NTRS)

    Hoffman, J. A.

    1977-01-01

    A qualitative description of all key elements of a complete wind energy system computer analysis code is presented. The analysis system addresses the coupled dynamics characteristics of wind energy systems, including the interactions of the rotor, tower, nacelle, power train, control system, and electrical network. The coupled dynamics are analyzed in both the frequency and time domain to provide the basic motions and loads data required for design, performance verification and operations analysis activities. Elements of the coupled analysis code were used to design and analyze candidate rotor articulation concepts. Fundamental results and conclusions derived from these studies are presented.

  9. Tower Camera Handbook

    SciTech Connect

    Moudry, D

    2005-01-01

    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 comparison with the albedo that can be calculated from downward-looking radiometers, as well as some indication of present weather. Similarly, during spring time, the camera images show the changes in the ground albedo as the snow melts. The tower images are saved in hourly intervals. In addition, two other cameras, the skydeck camera in Barrow and the piling camera in Atqasuk, show the current conditions at those sites.

  10. The Tower Challenge

    NSDL National Science Digital Library

    John Eichinger

    2009-05-30

    This activity is an exciting and highly interactive opportunity for students to exercise their creativity and design skills. Working in cooperative groups, students are challenged to explore the geometry of tower design and construction, first by experime

  11. Hoover Dam Intake Towers

    USGS Multimedia Gallery

    Hoover Dam impounds Lake Mead and provides drinking water and hydroelectric power to the surrounding area. It was constructed between 1931 and 1936. The Intake Towers are where water enters to generate electricity....

  12. Tower O' Power

    NSDL National Science Digital Library

    Integrated Teaching and Learning Program,

    In this activity, students learn about creating a design directly from a CAD (computer-aided design) program. They will design a tower in CAD and manufacture the parts with a laser cutter. A competition determines the tower design with the best strength:weight ratio. Students also investigate basic structural truss concepts and stress concentrations. Partnership with a local college or manufacturing center is necessary for the completion of this project.

  13. Drop Tower Workshop

    NASA Technical Reports Server (NTRS)

    Urban, David

    2013-01-01

    Ground based microgravity facilities are an important proving ground for space experiments, ground-based research and space hardware risk mitigation. An overview of existing platforms will be discussed with an emphasis on drop tower capabilities. The potential for extension to partial gravity conditions will be discussed. Input will be solicited from attendees for their potential to use drop towers in the future and the need for enhanced capabilities (e.g. partial gravity)

  14. Hurricane Frances Rain Towers

    NSDL National Science Digital Library

    Lori Perkins

    2005-04-11

    NASAs TRMM spacecraft allows us to look under Hurricane Frances clouds to see the rain structure. Spikes in the rain structure known as "Hot Towers" indicate storm intensity. The "hot towers" which refers to the tall cumulonimbus, has been seen as one of the mechanisms by which the intensity of a tropical cyclone is maintained. Because of the size (1-5 km) and short duration (30 minute to 2 hours) of these hot towers, studies of these events have been limited to descriptive studies from aircraft observations, although a few have attempted to use the presence of hot towers in a predictive capacity. Before TRMM, no data set exists that can show globally and definitively the presence of these hot towers in cyclone systems. Aircraft radar studies of individual storms lack global coverage. Global microwave or Infrared sensor observations do not provide the needed spatial resolution. With a ground resolution of 5 km, the TRMM Precipitation Radar provided the needed data set for examining the predictive value of hot towers in cyclone intensification.

  15. Surface and Tower Meteorological Instrumentation at Barrow (METTWR4H) Handbook

    SciTech Connect

    Ritsche, MT

    2008-04-01

    The Barrow meteorology station (BMET) uses mainly conventional in situ sensors mounted at four different heights (2m, 10m, 20m and 40m) on a 40 m tower to obtain profiles of wind speed, wind direction, air temperature, dew point and humidity. It also obtains barometric pressure, visibility and precipitation data from sensors at the base of the tower. Additionally, a Chilled Mirror Hygrometer and an Ultrasonic wind speed sensor are located near the 2m level for comparison purposes.

  16. Neural Network Based Interpolation of Wind Tunnel Test Data

    Microsoft Academic Search

    S. Thamarai Selvi; S. Rama; E. Mahendran

    2007-01-01

    The main objective of this research is to design a generalized framework for knowledge based management system (KBMS). This proposed system captures the knowledge of experts and the knowledge acquired is used for designing new systems. Wind Tunnel Test data of missiles has been taken into consideration for knowledge management in this research work and the interpolation of wind tunnel

  17. Technical Status Report for US Wind Farmers Network

    SciTech Connect

    Daniels, Lisa

    2003-02-19

    The theme of the work in this quarter was community-based wind and locally owned wind projects. The work Windustry has done is just beginning to touch the heart of the matter for a hugely interested audience of rural landowners and rural communities. We revised and published a Windustry Newsletter on two farmer owned wind projects called Minwind I and Minwind II. This article was largely researched and written last quarter but the principal individuals that organized the wind projects didn't want any more farmers calling them up than they already had, so they urged us to put a hold on the article or not publish it. This presented a unique problem for Windustry. Up to this point, we had not dealt with generating too much attention for a wind energy project. The story of a group of farmers and individuals pooling their resources for two locally owned commercial-scale wind projects is very compelling and the organizers of the projects were getting a great deal of attention from other farmers that want more details on the project. However, the organizers committed a large amount of their own resources toward the set up of this project which took many hours with their legal counsel and they did not have the capacity or the desire to provide answers for all the other farmers and individuals who were requesting information. Windustry worked with the business entity and did not publish the newsletter until we resolved some of the problems with the high level of interest in this project. Windustry resolved to address this issue by creating a custom track in the state and regional wind energy conference held in Minneapolis, November 21-22, 2002. There were a few sessions in the Landowner and Citizen Workshops track that were specifically created to talk about the ''how-to's for rural landowners to put together their own projects. Also, the conference's Community-Based Wind track addressed what makes a good project and what moneylenders are looking for when they evaluate wind projects. All of this contributed to the general knowledge base for other farmers to understand what it takes to put together their own wind energy enterprise. In a limited way, Windustry is beginning to define, differentiate and explore new types of wind energy business models. A good initial step is defining community-based wind as projects that are publicly owned--by a municipality, a rural electric coop, a county, or public entity like a school system, or hospital or jail. Ultimately, this work will lead to new materials on wind energy business models for rural landowners and communities.

  18. Comparison of Artificial Neural Networks and ARIMA statistical models in simulations of target wind time series

    NASA Astrophysics Data System (ADS)

    Kolokythas, Kostantinos; Vasileios, Salamalikis; Athanassios, Argiriou; Kazantzidis, Andreas

    2015-04-01

    The wind is a result of complex interactions of numerous mechanisms taking place in small or large scales, so, the better knowledge of its behavior is essential in a variety of applications, especially in the field of power production coming from wind turbines. In the literature there is a considerable number of models, either physical or statistical ones, dealing with the problem of simulation and prediction of wind speed. Among others, Artificial Neural Networks (ANNs) are widely used for the purpose of wind forecasting and, in the great majority of cases, outperform other conventional statistical models. In this study, a number of ANNs with different architectures, which have been created and applied in a dataset of wind time series, are compared to Auto Regressive Integrated Moving Average (ARIMA) statistical models. The data consist of mean hourly wind speeds coming from a wind farm on a hilly Greek region and cover a period of one year (2013). The main goal is to evaluate the models ability to simulate successfully the wind speed at a significant point (target). Goodness-of-fit statistics are performed for the comparison of the different methods. In general, the ANN showed the best performance in the estimation of wind speed prevailing over the ARIMA models.

  19. The nominal cooling tower

    SciTech Connect

    Burger, R. [Burger Associates, Dallas, TX (United States)

    1995-12-31

    The heat Rejection Industry defines a nominal cooling tower as circulating three gallons of water per minute (GPM) per ton of refrigeration from entering the tower at 95{degrees}F. Hot Water temperature (HWT) Leaving at 85{degrees}F Cold Water Temperature (CWT) at a Design Wet Bulb of 70{degrees}F (WBT). Manufacturers then provide a selection chart based on various wet bulb temperatures and HWTs. The wet bulb fluctuates and varies through out the world since it is the combination ambient temperature, relative humidity, and/or dew point. Different HWT and CWT requirements are usually charted as they change, so that the user can select the nominal cooling tower model recommended by the manufacturer. Ask any HVAC operator, refinery manager, power generating station operator what happens when the Wet Bulb reaches or exceeds the design WBT of the area. He probably will tell you, {open_quotes}My cooling tower works quite well, but in the summer time, I usually have trouble with it.{close_quotes} This occurs because he is operating a nominal cooling tower.

  20. Periodic pulsations from a three-bladed wind turbine

    Microsoft Academic Search

    Torbjörn Thiringer; Jan-Åke Dahlberg

    2001-01-01

    In this paper, periodic power pulsations from a three-bladed wind turbine are analyzed. The influence of wind shear, wind speed, turbulence intensity, rotor position and tower oscillation is investigated. No clear dependence between the periodic power components and the wind shear or turbulence intensity has been verified. The investigated turbine sometimes produces large power pulsations at the tower resonance frequency.

  1. 69. INTERIOR VIEW OF THE ABSORPTION TOWER BUILDING, ABSORPTION TOWER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    69. INTERIOR VIEW OF THE ABSORPTION TOWER BUILDING, ABSORPTION TOWER UNDER CONSTRUCTION. (DATE UNKNOWN). - United States Nitrate Plant No. 2, Reservation Road, Muscle Shoals, Muscle Shoals, Colbert County, AL

  2. View of the north tower porte cochere and flag tower, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of the north tower porte cochere and flag tower, looking southwest (duplicate of HABS No. DC-141-19) - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  3. 46. OCTAGONAL & WEST TOWERS FROM SOUTH TOWER ROOF, LOOKING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    46. OCTAGONAL & WEST TOWERS FROM SOUTH TOWER ROOF, LOOKING NORTHWEST, WITH WEST WING ROOF - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  4. 41. SOUTHEAST TOWER & EAST WING FROM SOUTH TOWER ROOF, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    41. SOUTHEAST TOWER & EAST WING FROM SOUTH TOWER ROOF, LOOKING EAST BY NORTHEAST - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  5. 42. SOUTHEAST TOWER & EAST WING ROOF FROM SOUTH TOWER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    42. SOUTHEAST TOWER & EAST WING ROOF FROM SOUTH TOWER ROOF, LOOKING EAST BY NORTHEAST - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  6. 45. OCTAGONAL, WEST & NORTHWEST TOWERS FROM SOUTH TOWER ROOF, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    45. OCTAGONAL, WEST & NORTHWEST TOWERS FROM SOUTH TOWER ROOF, LOOKING WEST BY NORTHWEST - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  7. Peak Wind Tool for General Forecasting

    NASA Technical Reports Server (NTRS)

    Barrett, Joe H., III; Short, David

    2008-01-01

    This report describes work done by the Applied Meteorology Unit (AMU) in predicting peak winds at Kennedy Space Center (KSC) and Cape Canaveral Air Force Station (CCAFS). The 45th Weather Squadron requested the AMU develop a tool to help them forecast the speed and timing of the daily peak and average wind, from the surface to 300 ft on KSC/CCAFS during the cool season. Based on observations from the KSC/CCAFS wind tower network , Shuttle Landing Facility (SLF) surface observations, and CCAFS sounding s from the cool season months of October 2002 to February 2007, the AMU created mul tiple linear regression equations to predict the timing and speed of the daily peak wind speed, as well as the background average wind speed. Several possible predictors were evaluated, including persistence , the temperature inversion depth and strength, wind speed at the top of the inversion, wind gust factor (ratio of peak wind speed to average wind speed), synoptic weather pattern, occurrence of precipitation at the SLF, and strongest wind in the lowest 3000 ft, 4000 ft, or 5000 ft.

  8. OPTIMUM METEOROLOGICAL AND AIR POLLUTION SAMPLING NETWORK SELECTION IN CITIES: VOLUME II. EVALUATION OF WIND FIELD PREDICTIONS FOR ST. LOUIS

    EPA Science Inventory

    This report is the second in a series on the development of a method for designing optimum meteorological and air pollution sampling networks and its application for St. Louis, Missouri (see PB-285 484). It involves the evaluation of the wind field network and utilizes wind data ...

  9. Radial basis function network wind tunnel wind speed detection algorithm based on PSO

    Microsoft Academic Search

    Chen Baoyuan; Sun Chenlin; Wu Qian; Lin Xirong

    2011-01-01

    corresponding model based on PS?. The PSO-RBF network has simple network structure, fast learning methods, good generalization ability. And it compared with other methods as a distinct advantage. Through simulation of MATLAB shows, it has small error that between the measured value of anemometer and simulated value of network of based on PSO-RBF, and obvious advantage over other optimization algorithm.

  10. THE TOWER HOUSE, LOOKING WEST. The tower house provided a ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    THE TOWER HOUSE, LOOKING WEST. The tower house provided a water tank on the second floor that gravity fed water to the Kineth house and farm buildings. The one-story addition to the west of the tower provided workshop space. The hog shed is seen on the left of the image and the concrete foundation of the upright silo is in the foreground on the right. - Kineth Farm, Tower House, 19162 State Route 20, Coupeville, Island County, WA

  11. Floating wind turbine system

    NASA Technical Reports Server (NTRS)

    Viterna, Larry A. (Inventor)

    2009-01-01

    A floating wind turbine system with a tower structure that includes at least one stability arm extending therefrom and that is anchored to the sea floor with a rotatable position retention device that facilitates deep water installations. Variable buoyancy for the wind turbine system is provided by buoyancy chambers that are integral to the tower itself as well as the stability arm. Pumps are included for adjusting the buoyancy as an aid in system transport, installation, repair and removal. The wind turbine rotor is located downwind of the tower structure to allow the wind turbine to follow the wind direction without an active yaw drive system. The support tower and stability arm structure is designed to balance tension in the tether with buoyancy, gravity and wind forces in such a way that the top of the support tower leans downwind, providing a large clearance between the support tower and the rotor blade tips. This large clearance facilitates the use of articulated rotor hubs to reduced damaging structural dynamic loads. Major components of the turbine can be assembled at the shore and transported to an offshore installation site.

  12. Analysis of a utility-interactive wind-photovoltaic hybrid system with battery storage using neural network

    Microsoft Academic Search

    Francois Giraud

    1999-01-01

    This dissertation investigates the application of neural network theory to the analysis of a 4-kW Utility-interactive Wind-Photovoltaic System (WPS) with battery storage. The hybrid system comprises a 2.5-kW photovoltaic generator and a 1.5-kW wind turbine. The wind power generator produces power at variable speed and variable frequency (VSVF). The wind energy is converted into dc power by a controlled, tree-phase,

  13. Cooling Towers, Energy Conservation Machines 

    E-print Network

    Burger, R.

    1980-01-01

    ------------~'l:~' COOLING TOWERS, ENERGY CONSERVATION MACHINES 1980 CONFERENCE ON INDUSTRIAL ENERGY CONSERVATION TECHNOLOGY Robert Burger B~rger Associates Dallas, Texas ABSTRACT Cooling towers, in all too many industrial plants, are often...

  14. Thermal Characteristics of Heating Towers

    NASA Astrophysics Data System (ADS)

    Fujita, Toshihiko; Kametani, Shigeki

    Thermal characteristics of heating towers for air-source heat pumps are studied in terms of the overall enthalpy-transfer coefficient. Ka. First. the method of counter-flow calculation is presented taking physical properties of ethylene glycol solutions into account. Next, both cooling-tower and heating-tower experiments are carried out in a small, induced-draft. counterflow tower packed with tubes of a staggerd arrangement. using water and commercial ethylene glycol solutions. The coefficient Ka measured in the heating-tower experiment shows a trend similar to that in the cooling-tower experiment. So. the data on cooling towers will be helpful to the thermal design of heating towers.

  15. Evaporation Tower With Prill Nozzles

    NASA Technical Reports Server (NTRS)

    Du Fresne, E. R.

    1984-01-01

    Tower more efficient than conventional evaporation equipment. Liquids such as milk and fruit juice concentrated by passing them through tiny nozzle to form droplets, then allowing droplets to fall through evacuated tower with cooled walls.

  16. Tower Investigation and the Egg

    NSDL National Science Digital Library

    Center for Engineering Educational Outreach,

    Towers have been a part of developed society for centuries, serving a variety of purposes, from watch towers to modern cell towers. In this activity, student groups design and build three types of towers (guyed or cable-supported, free-standing or self-standing, and monopole), engineering them to meet the requirements that they hold an egg one foot high for 15 seconds.

  17. A radar-based monitoring of the Collserola tower (Barcelona)

    NASA Astrophysics Data System (ADS)

    Luzi, G.; Crosetto, M.; Cuevas-González, M.

    2014-12-01

    This paper reports a set of experiments aiming at evaluating the capability of an innovative radar technique to measure the dynamic response of a 268 m high tower, the Collserola tower located in Barcelona, and its guys; the tension force of some guys is also estimated from the obtained vibration frequencies. The applied procedure was based on the use of a coherent radar system: temporal samples acquired using different observation geometries were processed to retrieve the vibration characteristics of both the tower and its guys. This was attained by observing the tower in a fully remote sensing mode, i.e. several hundred metres from the object, without installing any reflector on the tower, and under micro-tremor and wind-induced excitation. During the campaigns, which were spread over three years, the investigated technique demonstrated its capability to measure the dynamic response for a number of different points of the tower with high repeatability. The performed experiments also allowed distinguishing and characterizing the different contributions of the tower and the guys.

  18. Meteorological Monitoring And Warning Computer Network

    NASA Technical Reports Server (NTRS)

    Evans, Randolph J.; Dianic, Allan V.; Moore, Lien N.

    1996-01-01

    Meteorological monitoring system (MMS) computer network tracks weather conditions and issues warnings when weather hazards are about to occur. Receives data from such meteorological instruments as wind sensors on towers and lightning detectors, and compares data with weather restrictions specified for outdoor activities. If weather violates restriction, network generates audible and visible alarms to alert people involved in activity. Also displays weather and toxic diffusion data and disseminates weather forecasts, advisories, and warnings to workstations.

  19. Remote Survey of the Leaning Tower of Pisa by Interferometric Sensing

    Microsoft Academic Search

    Carlo Atzeni; Alberto Bicci; Devis Dei; Matteo Fratini; Massimiliano Pieraccini

    2010-01-01

    The Leaning Tower of Pisa, one of the world-famous architectural marvels of Italian heritage, needs continuous surveying to assess its stability. In this letter, remote-sensing equipment recently developed by the authors, based on the principle of microwave radar interferometry, has been experimented to measure the frequency response of the Tower without requiring any contact with its structure. Wind and human

  20. Remote Survey of the Leaning Tower of Pisa by Interferometric Sensing

    Microsoft Academic Search

    Carlo Atzeni; Alberto Bicci; Devis Dei; Matteo Fratini; Massimiliano Pieraccini

    2009-01-01

    9 any contact with its structure. Wind and human traffic were used 10 as natural excitation sources, allowing the natural frequencies 11 of the first vibration mode of the Tower to be measured in the 12 north-south and in the west-east directions. Modal shapes of 13 the Tower vibrations were also obtained from data acquired by 14 the radar. 15

  1. Exploding Stars with Magnetic Towers

    Microsoft Academic Search

    Dmitri Uzdensky; Andrew MacFadyen

    2005-01-01

    We consider the formation and propagation of a magnetically dominated outflow, similar to Lynden-Bell's ``magnetic tower,'' inside a collapsing star. We calculate the structure of this flow as it burrows through the stellar envelope. The passage of the tower through the star drives a strong bow shock behind which an over-pressured cocoon forms. In turn, the cocoon collimates the tower

  2. FLYWHEEL ENERGY STORAGE SYSTEM TO IMPROVE THE INTEGRATION OF WIND GENERATORS INTO A NETWORK

    Microsoft Academic Search

    Ludovic Leclercq; Christophe Saudemont; Benoît Robyns; Gabriel Cimuca; Mircea M. Radulescu

    2003-01-01

    The association of a Variable-Speed Wind Generator (VSWG) and a Flywheel Energy Storage System (FESS) with the aim to improve the integration of such generators in a network is studied. A resonant controller-based network connection and a fuzzy-logic supervisory are proposed. A 3 kW test bench is described, and a first experiment which validates the principle of the FESS is

  3. COOLING TOWER PLUME MODEL

    EPA Science Inventory

    A review of recently reported cooling tower plume models yields none that is universally accepted. The entrainment and drag mechanisms and the effect of moisture on the plume trajectory are phenomena which are treated differently by various investigators. In order to better under...

  4. Cooling Towers, The Debottleneckers

    E-print Network

    Burger, R.

    Power generating plants and petro-chemical works are always expanding. An on-going problem is to identify and de-bottle neck restricting conditions of growth. The cooling tower is a highly visible piece of equipment. Most industrial crossflow units...

  5. PERFORMANCE ANALYSIS OF MECHANICAL DRAFT COOLING TOWER

    SciTech Connect

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

    2009-02-10

    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.

  6. Dynamic Modeling and Control of DFIG-Based Wind Turbines Under Unbalanced Network Conditions

    Microsoft Academic Search

    Lie Xu; Yi Wang

    2007-01-01

    This paper presents an analysis and control design of a doubly-fed induction generator (DFIG)-based wind generation system operating under unbalanced network conditions. A DFIG system model in the positive and negative synchronous reference frames is presented. Variations of stator active and reactive powers and generator torque are fully defined in the presence of negative sequence voltage and current. Alternative DFIG

  7. Installation and initial operation of a 4100 watt wind turbine

    NASA Technical Reports Server (NTRS)

    Tryon, H. B.; Richards, T.

    1975-01-01

    The results are presented of 211 days of operation of the 4.1 kilowatt wind turbine, which was the largest commercially available wind turbine. The wind turbine, electric controls and load bank, and the pivoted tower are described.

  8. Coupled Dynamic Analysis of Multiple Unit Floating Offshore Wind Turbine

    E-print Network

    Bae, Yoon Hyeok

    2013-04-23

    floating wind turbines, so the effects of such high-frequency excitations from the tower and blades need to be checked. 5 Another concept for floating offshore wind farms is the Multiple Unit Floating Offshore Wind Turbine (MUFOWT). This model...

  9. Network Power Flow Control of Variable Speed Wind Turbine

    Microsoft Academic Search

    D. Aouzellag; K. Ghedamsi; E. M. Berkouk

    2007-01-01

    In this paper, a grid connected wind power generation scheme using a doubly fed induction generator (DFIG) is studied. The objectives of this paper are: - Modelling and simulating of a DFIG operating in two quadrants (torque-speed plane). - Analysing employs a stator flux vector control algorithm used with a space vector modulated matrix converter controlling rotor current. - Enabling

  10. Automation of Some Operations of a Wind Tunnel Using Artificial Neural Networks

    NASA Technical Reports Server (NTRS)

    Decker, Arthur J.; Buggele, Alvin E.

    1996-01-01

    Artificial neural networks were used successfully to sequence operations in a small, recently modernized, supersonic wind tunnel at NASA-Lewis Research Center. The neural nets generated correct estimates of shadowgraph patterns, pressure sensor readings and mach numbers for conditions occurring shortly after startup and extending to fully developed flow. Artificial neural networks were trained and tested for estimating: sensor readings from shadowgraph patterns, shadowgraph patterns from shadowgraph patterns and sensor readings from sensor readings. The 3.81 by 10 in. (0.0968 by 0.254 m) tunnel was operated with its mach 2.0 nozzle, and shadowgraph was recorded near the nozzle exit. These results support the thesis that artificial neural networks can be combined with current workstation technology to automate wind tunnel operations.

  11. Field measurements of Di Wang Tower during Typhoon York

    Microsoft Academic Search

    Y. L Xu; S Zhan

    2001-01-01

    Di Wang Tower is the highest building located at the hub of the Shenzhen financial and commercial area, about 2km from the Hong Kong border. On 16 September 1999, Typhoon York, which is the strongest typhoon since 1983 and the typhoon of longest duration on record, attacked Hong Kong and Shenzhen. The wind and structural monitoring system installed in Di

  12. New Scientist: Construction of Worlds Largest Tower to Begin

    NSDL National Science Digital Library

    This article from the New Scientist talks about the building of the world's tallest building in Dubai, United Arab Emirates. The tower construction will be completed in 2008 and will result in a structure 800 meters tall. The article discusses how the building has been designed to address a primary concern for buildings of this height--wind.

  13. Active Control of Wind-Tunnel Model Aeroelastic Response Using Neural Networks

    NASA Technical Reports Server (NTRS)

    Scott, Robert C.

    2000-01-01

    NASA Langley Research Center, Hampton, VA 23681 Under a joint research and development effort conducted by the National Aeronautics and Space Administration and The Boeing Company (formerly McDonnell Douglas) three neural-network based control systems were developed and tested. The control systems were experimentally evaluated using a transonic wind-tunnel model in the Langley Transonic Dynamics Tunnel. One system used a neural network to schedule flutter suppression control laws, another employed a neural network in a predictive control scheme, and the third employed a neural network in an inverse model control scheme. All three of these control schemes successfully suppressed flutter to or near the limits of the testing apparatus, and represent the first experimental applications of neural networks to flutter suppression. This paper will summarize the findings of this project.

  14. Tornado type wind turbines

    DOEpatents

    Hsu, Cheng-Ting (Ames, IA)

    1984-01-01

    A tornado type wind turbine has a vertically disposed wind collecting tower with spaced apart inner and outer walls and a central bore. The upper end of the tower is open while the lower end of the structure is in communication with a wind intake chamber. An opening in the wind chamber is positioned over a turbine which is in driving communication with an electrical generator. An opening between the inner and outer walls at the lower end of the tower permits radially flowing air to enter the space between the inner and outer walls while a vertically disposed opening in the wind collecting tower permits tangentially flowing air to enter the central bore. A porous portion of the inner wall permits the radially flowing air to interact with the tangentially flowing air so as to create an intensified vortex flow which exits out of the top opening of the tower so as to create a low pressure core and thus draw air through the opening of the wind intake chamber so as to drive the turbine.

  15. Tornado type wind turbines

    SciTech Connect

    Hsu, Ch.-T.

    1984-06-05

    A tornado type wind turbine has a vertically disposed wind collecting tower with spaced apart inner and outer walls and a central bore. The upper end of the tower is open while the lower end of the structure is in communication with a wind intake chamber. An opening in the wind chamber is positioned over a turbine which is in driving communication with an electrical generator. An opening between the inner and outer walls at the lower end of the tower permits radially flowing air to enter the space between the inner and outer walls while a vertically disposed opening in the wind collecting tower permits tangentially flowing air to enter the central bore. A porous portion of the inner wall permits the radially flowing air to interact with the tangentially flowing air so as to create an intensified vortex flow which exits out of the top opening of the tower so as to create a low pressure core and thus draw air through the opening of the wind intake chamber so as to drive the turbine.

  16. An Analysis of Peak Wind Speed Data from Collocated Mechanical and Ultrasonic Anemometers

    NASA Technical Reports Server (NTRS)

    Short, David A.; Wells, Leonard A.; Merceret, Francis J.; Roeder, William P.

    2005-01-01

    This study focuses on a comparison of peak wind speeds reported by mechanical and ultrasonic anemometers at Cape Canaveral Air Force Station and Kennedy Space Center (CCAFS/KSC) on the east central coast of Florida and Vandenberg Air Force Base (VAFB) on the central coast of California. The legacy mechanical wind instruments on CCAFS/KSC and VAFB weather towers are being changed from propeller-and-vane (CCAFS/KSC) and cup-and-vane (VAFB) sensors to ultrasonic sensors under the Range Standardization and Automation (RSA) program. The wind tower networks on KSC/CCAFS and VAFB have 41 and 27 towers, respectively. Launch Weather Officers, forecasters, and Range Safety analysts at both locations need to understand the performance of the new wind sensors for a myriad of reasons that include weather warnings, watches, advisories, special ground processing operations, launch pad exposure forecasts, user Launch Commit Criteria (LCC) forecasts and evaluations, and toxic dispersion support. The Legacy sensors measure wind speed and direction mechanically. The ultrasonic RSA sensors have no moving parts. Ultrasonic sensors were originally developed to measure very light winds (Lewis and Dover 2004). The technology has evolved and now ultrasonic sensors provide reliable wind data over a broad range of wind speeds. However, because ultrasonic sensors respond more quickly than mechanical sensors to rapid fluctuations in speed, characteristic of gusty wind conditions, comparisons of data from the two sensor types have shown differences in the statistics of peak wind speeds (Lewis and Dover 2004). The 45th Weather Squadron (45 WS) and the 30 WS requested the Applied Meteorology Unit (AMU) to compare data from RSA and Legacy sensors to determine if there are significant differences in peak wind speed information from the two systems.

  17. Development of solar tower observatories

    Microsoft Academic Search

    Gudrun Wolfschmidt

    2005-01-01

    Because the horizontal solar telescope, the Snow Telescope in Yerkes Observatory, was affected by air-currents from the warmed-up soil, George Ellery Hale had the idea of a tower telescope. In 1904, the 60-foot tower in Mt. Wilson was ready, in 1908 the 150-foot tower was built with the help of the Carnegie foundation. After World War I, Germany made heavy

  18. STATISTICAL CORRELATIONS OF SURFACE WIND DATA: A COMPARISON BETWEEN A NATIONAL WEATHER SERVICE STATION AND A NEARBY AEROMETRIC MONITORING NETWORK

    EPA Science Inventory

    This report presents a statistical analysis of wind data collected at a network of stations in the Southeast Ohio River Valley. The purpose of this study is to determine the extent to which wind measurements made by the National Weather Service (NWS) station at the Tri-State Airp...

  19. Initial Operation Results and Performance Evaluation of WINDS (Wideband Inter-Networking engineering test and Demonstration Satellite)

    NASA Astrophysics Data System (ADS)

    Arikawa, Yoshihisa; Nakamura, Yasuo; Araki, Tsunehiko; Fujiwara, Yuuichi; Baba, Isao; Baba, Kenichi

    WINDS was launched in late February 2008 to demonstrate technologies enabling an ultra-high data rate communication network. WINDS is performing initial functional verifications of onboard components and systems. This paper describes the initial operation results on orbit and evaluates the performance based on the design and simulation data.

  20. Application of Network Planning to Teaching Wind-Surfing

    ERIC Educational Resources Information Center

    Zybko, Przemyslaw; Jaczynowski, Lech

    2008-01-01

    Study aim: To determine the effects of network planning on teaching untrained subjects windsurfing. Material and methods: Untrained physical education students (n = 390), aged 19-23 years, took part in the study while staying on a summer camp. They were randomly assigned into two groups: experimental (n = 216) and control (n = 174). Two methods of…

  1. Influence of Wind Turbulence on Yaw-control Gears in Wind Turbine

    Microsoft Academic Search

    Kazuo Suzuki; Naoki Hoshino; Noboru Inomata; Hiroshi Kimura; Tamiya Fujiwara

    2009-01-01

    This paper describes an influence of wind turbulence on yaw-control gears of nacelle in a wind power station. This site is located in Tappi cape of Aomori prefecture where is characterized by a big wind turbulence due to the western strong wind and a steep slope of the cape. In this paper two adjacent wind towers are dealt with among

  2. The Physics of Shot Towers

    NASA Astrophysics Data System (ADS)

    Lipscombe, Trevor C.; Mungan, Carl E.

    2012-04-01

    In the late 18th and throughout the 19th century, lead shot for muskets was prepared by use of a shot tower. Molten lead was poured from the top of a tower and, during its fall, the drops became spherical under the action of surface tension. In this article, we ask and answer the question: How does the size of the lead shot depend on the height of the tower? In the process, we explain the basic technology underlying an important historical invention (the shot tower) and use simple physics (Newtonian mechanics and the thermodynamic laws of cooling) to model its operation.

  3. Dynamic Responses and Vibration Control of the Transmission Tower-Line System: A State-of-the-Art Review

    PubMed Central

    Chen, Bo; Guo, Wei-hua; Li, Peng-yun; Xie, Wen-ping

    2014-01-01

    This paper presented an overview on the dynamic analysis and control of the transmission tower-line system in the past forty years. The challenges and future developing trends in the dynamic analysis and mitigation of the transmission tower-line system under dynamic excitations are also put forward. It also reviews the analytical models and approaches of the transmission tower, transmission lines, and transmission tower-line systems, respectively, which contain the theoretical model, finite element (FE) model and the equivalent model; shows the advances in wind responses of the transmission tower-line system, which contains the dynamic effects under common wind loading, tornado, downburst, and typhoon; and discusses the dynamic responses under earthquake and ice loads, respectively. The vibration control of the transmission tower-line system is also reviewed, which includes the magnetorheological dampers, friction dampers, tuned mass dampers, and pounding tuned mass dampers. PMID:25105161

  4. Dynamic responses and vibration control of the transmission tower-line system: a state-of-the-art review.

    PubMed

    Chen, Bo; Guo, Wei-hua; Li, Peng-yun; Xie, Wen-ping

    2014-01-01

    This paper presented an overview on the dynamic analysis and control of the transmission tower-line system in the past forty years. The challenges and future developing trends in the dynamic analysis and mitigation of the transmission tower-line system under dynamic excitations are also put forward. It also reviews the analytical models and approaches of the transmission tower, transmission lines, and transmission tower-line systems, respectively, which contain the theoretical model, finite element (FE) model and the equivalent model; shows the advances in wind responses of the transmission tower-line system, which contains the dynamic effects under common wind loading, tornado, downburst, and typhoon; and discusses the dynamic responses under earthquake and ice loads, respectively. The vibration control of the transmission tower-line system is also reviewed, which includes the magnetorheological dampers, friction dampers, tuned mass dampers, and pounding tuned mass dampers. PMID:25105161

  5. Integration of offshore wind farms through high voltage direct current networks

    NASA Astrophysics Data System (ADS)

    Livermore, Luke

    The integration of offshore wind farms through Multi Terminal DC (MTDC) networks into the GB network was investigated. The ability of Voltage Source Converter (VSC) High Voltage Direct Current (HVDC) to damp Subsynchronous Resonance (SSR) and ride through onshore AC faults was studied. Due to increased levels of wind generation in Scotland, substantial onshore and offshore reinforcements to the GB transmission network are proposed. Possible inland reinforcements include the use of series compensation through fixed capacitors. This potentially can lead to SSR. Offshore reinforcements are proposed by two HVDC links. In addition to its primary functions of bulk power transmission, a HVDC link can be used to provide damping against SSR, and this function has been modelled. Simulation studies have been carried out in PSCAD. In addition, a real-time hardware-in-the-loop HVDC test rig has been used to implement and validate the proposed damping scheme on an experimental platform. When faults occur within AC onshore networks, offshore MTDC networks are vulnerable to DC overvoltages, potentially damaging the DC plant and cables. Power reduction and power dissipation control systems were investigated to ride through onshore AC faults. These methods do not require dedicated fast communication systems. Simulations and laboratory experiments are carried out to evaluate the control systems, with the results from the two platforms compared..

  6. Natural-draft Cooling Tower

    USGS Multimedia Gallery

    Natural-draft cooling towers and one of two intake screens and associated pumps for the Tennessee Valley Authority, Sequoyah Nuclear Power Plant, Tennessee. Natural-draft tower airflow is drawn through the packing or fill (distributed at the base) by means of the small density difference between the...

  7. Weird Geology: The Devil's Tower

    NSDL National Science Digital Library

    Lee Krystek

    This page features a brief introduction to the several theories about the geological processes that formed Devil's Tower, which rises 1,267 feet above the nearby Belle Fourche River and is still considered a sacred place by some Native American Tribes. Information on climbing the tower as well as images and a cross section are provided.

  8. Fluvial network analysis on Titan: Evidence for subsurface structures and west-to-east wind flow, southwestern Xanadu

    E-print Network

    Perfect, Ed

    Fluvial network analysis on Titan: Evidence for subsurface structures and west-to-east wind flow; published 25 November 2009. [1] Data of Titan's surface from the Cassini-Huygens mission show inferred, indicating that a variety of factors control fluvial drainage on Titan. Drainage network patterns

  9. SkyTower Telecommunications

    NSDL National Science Digital Library

    Helios is the name of an unmanned, solar powered aircraft that broke many records and made history on its first successful flight last summer. With more flights scheduled for this summer, there is growing interest in the potential applications of so-called "atmospheric satellites" like Helios. This Web site, operated by the company that developed the prototype, has lots of information about the aircraft, its specifications, and, most importantly, its possible uses. The main focus is on telecommunications; because this kind of aircraft could remain at high altitudes for long periods of time, it could be used as an extremely tall tower that relays signals to and from ground stations. A video clip demonstrating this technology is also provided on the site.

  10. The Tower of London

    NSDL National Science Digital Library

    As one of the most famous complexes of historic structures in the world, it stands to reason that the Tower of London would have a plethora of websites dedicated to exploring its development and rather crucial role in English history. Begun by William the Conquerer, the castle has been improved and added upon numerous times over the past 900 years, and now includes dozens of smaller structures within its walls. Developed by staff members at Knight International, this site is a real treat for those seeking to learn more about this historic site, or those who might be planning a visit in the future. The site contains approximately a dozen different areas of interest, ranging from a fine virtual tour of the grounds, a section devoted to the omnipresent ravens and, of course, a copious amount of materials on the Crown Jewels.

  11. Short-term load and wind power forecasting using neural network-based prediction intervals.

    PubMed

    Quan, Hao; Srinivasan, Dipti; Khosravi, Abbas

    2014-02-01

    Electrical power systems are evolving from today's centralized bulk systems to more decentralized systems. Penetrations of renewable energies, such as wind and solar power, significantly increase the level of uncertainty in power systems. Accurate load forecasting becomes more complex, yet more important for management of power systems. Traditional methods for generating point forecasts of load demands cannot properly handle uncertainties in system operations. To quantify potential uncertainties associated with forecasts, this paper implements a neural network (NN)-based method for the construction of prediction intervals (PIs). A newly introduced method, called lower upper bound estimation (LUBE), is applied and extended to develop PIs using NN models. A new problem formulation is proposed, which translates the primary multiobjective problem into a constrained single-objective problem. Compared with the cost function, this new formulation is closer to the primary problem and has fewer parameters. Particle swarm optimization (PSO) integrated with the mutation operator is used to solve the problem. Electrical demands from Singapore and New South Wales (Australia), as well as wind power generation from Capital Wind Farm, are used to validate the PSO-based LUBE method. Comparative results show that the proposed method can construct higher quality PIs for load and wind power generation forecasts in a short time. PMID:24807030

  12. Short-term Wind Power Prediction for Offshore Wind Farms -Evaluation of Fuzzy-Neural Network Based Models

    E-print Network

    Paris-Sud XI, Université de

    of offshore farms and their secure integration to the grid. Modeling the behavior of large wind farms based wind power forecasting model is described. Its perfor- mance is assessed for offshore conditions offshore wind farms is developed. In order to deal with the spread of the turbines in such cases, methods

  13. Cooling Towers- Energy Conservation Strategies Understanding Cooling Towers

    E-print Network

    Smith, M.

    gets hotter and hotter due to inadequate cooling water. Engineers finally recognize that the limiting factor in production is the quality of the cold water temperature that is returning from the cooling tower. Basic technology will be discussed...

  14. Improvements of wind noise reduction systems in the International Monitoring System infrasound network

    NASA Astrophysics Data System (ADS)

    Kramer, Alfred Christian; Marty, Julien

    2015-04-01

    The objective of this poster is to present the efforts made by the PTS over the last four years to assess and improve the robustness and efficiency of wind noise reduction systems. This work includes the improvement of the design of the pipe arrays by modelling the frequency response of the different types of filtering systems used within the IMS (International Monitoring System) infrasound network. It also includes the investigation and testing of new acoustic filtering system materials / components to improve the robustness of the pipe arrays. Efforts were also put into the improvement of pipe array design in order to enhance their flexibility to adapt to the station environmental conditions. Finally wind noise reduction system design was also enhanced to reduce maintenance activities and costs, as well as to extend their life cycle.

  15. Spatial Representativeness of Flux Tower Sites: A Comparison Between Tower and Aircraft Eddy-Covariance Fluxes

    NASA Astrophysics Data System (ADS)

    Caulton, D.; Shepson, P. B.; Munger, J. W.; Hollinger, D. Y.; Saatchi, S. S.; Moghaddam, M.; Stirm, B. H.

    2013-12-01

    Development and testing of regional and global scale ecosystem models rely on analysis of data from flux towers that have footprint scales (~1 km2) that are much smaller and contain relatively homogeneous land use types. This approach tends to assume that the patchwork approach appropriately represents regions that are, especially on larger scale, much more heterogeneous in terms of land cover, soil moisture, topography and climatology, etc. While aircraft platforms provide snapshot views of NEE, they have access to essentially any environment and can access difficult and heterogeneous environments. We used an instrumented aircraft platform equipped with a 50 Hz wind probe and GPS/INS and a 10 Hz Picarro CO2/H2O analyzer to measure eddy covariance fluxes over larger spatial scales (~20 km2) over and near Howland Forest, ME, Harvard Forest, MA and Duke Forest, NC, as part of the Airborne Observatory of Subcanopy and Subsurface (AirMOSS) mission campaigns. Flux measurements were conducted for varying land cover types in these forests in July, 2012 and June-August, 2013. Measured fluxes will be compared with tower fluxes from each of the three sites to investigate the quality of the aircraft data, and the ability to assess local-regional scale variability and the spatial representativeness of these towers, with respect to the larger scale fluxes. In addition, soil moisture data from a NASA G-III aircraft will be used to investigate spatial representativeness and the soil moisture dependence of the fluxes.

  16. Modular Towers Construction and Diophantine Questions

    E-print Network

    Fried, Michael

    Modular Towers Construction and Diophantine Questions Pierre D`ebes Abstract. Modular towers|). The tower of modular curves X1 (pn ) (n>0) is the original example: the group G is then the dihedral group Dp. There are diophantine conjectures on modular towers, inspired by modular curves: the spirit

  17. You're a What?: Tower Technician

    ERIC Educational Resources Information Center

    Vilorio, Dennis

    2012-01-01

    In this article, the author talks about the role and functions of a tower technician. A tower technician climbs up the face of telecommunications towers to remove, install, test, maintain, and repair a variety of equipment--from antennas to light bulbs. Tower technicians also build shelters and radiofrequency shields for electronic equipment, lay…

  18. WindFloat: A floating foundation for offshore wind turbines

    Microsoft Academic Search

    Dominique Roddier; Christian Cermelli; Alexia Aubault; Alla Weinstein

    2010-01-01

    This manuscript summarizes the feasibility study conducted for the WindFloat technology. The WindFloat is a three-legged floating foundation for multimegawatt offshore wind turbines. It is designed to accommodate a wind turbine, 5 MW or larger, on one of the columns of the hull with minimal modifications to the nacelle and rotor. Potential redesign of the tower and of the turbine

  19. Performance of Tornado Wind Energy Conversion Systems

    SciTech Connect

    Volk, T.

    1982-09-01

    The flow characteristics and power production capabilities of the Tornado Wind Energy Conversion System (TWECS) are examined. Experimental results indicate that the confined vortex in the tower of TWECS rotates approximately as a solid body and only supplements total power production, most of which comes from the tower acting as a bluff body. Wrapped tower experiments were performed by fitting a plastic shroud 360 deg around the tower from the top of the bottom inlet to the tower exit level which transformed the TWECS into a hollow, raised cylinder. Coefficient of power is compared for louvered towers vs. wrapped tower. The fact that the wrapped tower performs as well as the louvered tower suggests that it is the pressure difference between the bottom inlet region and the region above the tower (where the pressure of the ambient flow will be somewhat reduced owing to its acceleration over the bluff body of the tower) which determines the vertical force on the fluid within the tower.

  20. Hoover Dam Intake Towers Panorama

    USGS Multimedia Gallery

    Hoover Dam impounds Lake Mead and provides drinking water and hydroelectric power to the surrounding area. It was constructed between 1931 and 1936. The Intake Towers are where water enters to generate electricity....

  1. Cooling Tower Energy Conservation Optimization 

    E-print Network

    Burger, R.

    1985-01-01

    COOLING TOWER ENERGY CONSERVATION OPTIMIZATION Robert Burger Burger Associates, Inc. Dallas, Texas Energy conservation strategies involve more than examination of fan horsepower. Colder water and pumping head provide vast savings potentials...

  2. Ozonation of cooling tower waters

    NASA Technical Reports Server (NTRS)

    Humphrey, M. F.; French, K. R.; Howe, R. D. (inventors)

    1979-01-01

    Continuous ozone injection into water circulating between a cooling tower and heat exchanger with heavy scale deposits inhibits formation of further deposits, promotes flaking of existing deposits, inhibits chemical corrosion and controls algae and bacteria.

  3. World Federation of Great Towers

    NSDL National Science Digital Library

    The World Federation of Great Towers (WFGT) "is an association of international monuments which join together to foster global awareness and develop international opportunities for promotion." The organization provides this eye-catching site that contains detailed information and pictures of over twenty towers from around the world. After giving a brief background summary of each tower's location and notable characteristics, specifications and technical data are provided to give an impression of the scale of the structures and the engineering skill that was needed in their construction. Although only the buildings that are members of the WFGT are featured online, the collection does a good job of capturing some of the most impressive towers in existence.

  4. A fiber optic wind vane: A conceptual view

    SciTech Connect

    Parker, M.J. [Westinghouse Savannah River Co., Aiken, SC (United States); Heaverly, M. [Met One Instruments, Inc., Grants Pass, OR (United States)

    1996-07-01

    The use of tall towers for the normal operation of meteorological instrumentation is ideal for ensuring that representative measurements are obtained relative to the nearby terrain. Tall towers also expose instrumentation to unwanted environmental side-effects such as lightning surges. The proximity of many industrial observation sites for meteorological towers also introduces unwanted problems including radio frequency interference (RFI) from radio, television, or microwave transmitters, explosive environments, and electrical power cabling. Typical meteorological instrumentation systems incorporate protective mechanisms such as grounding networks, surge protectors and electrical shielding to combat electrical problems. Still, even with elaborate protective systems, damages to instrumentation and a loss of valid data can occur which often results in extended outages. The use of fiber optic technology in meteorological instrumentation holds great promise to eliminate many of the problems associated with monitoring on tall towers. A fiber optic sensor would be impervious to lightning surges and all forms of RFI. The sensor would provide a high signal to noise ratio output since little or no electrical interference would be involved in data transmission. A longer field life for mechanical devices such as a wind vane would be realized since all physical contact points, such as those found in a potentiometer, would be eliminated. Therefore, the precision, resolution, linearity, starting threshold and accuracy could be dramatically improved without the hindrance of moving parts.

  5. Method for predicting impulsive noise generated by wind turbine rotors

    Microsoft Academic Search

    L. A. Viterna

    1982-01-01

    Large wind turbines can generate both broad band and impulsive noises. These noises can be controlled by proper choice of rotor design parameters such as rotor location with respect to the supporting tower, tower geometry and tip speed. A method was developed to calculate the impulsive noise generated when the wind turbine blade experiences air forces that are periodic functions

  6. 7.2.9. Tower 7.2.10. Winterdienstgebude /

    E-print Network

    Berlin,Technische Universität

    .2.9.3.4.3 Überwachung der Notstromversorgung des Towers 7.2.9.3.5 Kälteversorgung des Towers / Cooling Supply of Tower 77.2.9. Tower 7.2.10. Winterdienstgebäude / Snow Service Buildings 7.2.11. Müllzentrale / Waste Area / Tower Operation 7.2.9.2. Wartung und Instandhaltung des Towers / Service and Maintenance on Tower 7

  7. Multi-objective optimization of solar tower power plants

    E-print Network

    Ábrahám, Erika

    Multi-objective optimization of solar tower power plants Pascal Richter Center for Computational · Optimization of solar tower power plants 1/20 #12;Introduction ­ Solar tower power plants Solar tower PS10 (11 of the solar tower Pascal Richter · Optimization of solar tower power plants 2/20 #12;Model of solar tower

  8. Direct adaptive control of wind energy conversion systems using Gaussian networks.

    PubMed

    Mayosky, M A; Cancelo, I E

    1999-01-01

    Grid connected wind energy conversion systems (WECS) present interesting control demands, due to the intrinsic nonlinear characteristics of windmills and electric generators. In this paper a direct adaptive control strategy for WECS control is proposed. It is based on the combination of two control actions: a radial basis zfunction network-based adaptive controller, which drives the tracking error to zero with user specified dynamics, and a supervisory controller, based on crude bounds of the system's nonlinearities. The supervisory controller fires when the finite neural-network approximation properties cannot be guaranteed. The form of the supervisor control and the adaptation law for the neural controller are derived from a Lyapunov analysis of stability. The results are applied to a typical turbine/generator pair, showing the feasibility of the proposed solution. PMID:18252585

  9. Relative importance of parameters affecting wind speed prediction using artificial neural networks

    NASA Astrophysics Data System (ADS)

    Ghorbani, M. A.; Khatibi, R.; Hosseini, B.; Bilgili, M.

    2013-10-01

    In traditional artificial neural networks (ANN) models, the relative importance of the individual meteorological input variables is often overlooked. A case study is presented in this paper to model monthly wind speed values using meteorological data (air pressure, air temperature, relative humidity, and precipitation), where the study also includes an estimate of the relative importance of these variables. Recorded monthly mean data are available at a gauging site in Tabriz, Azerbaijan, Iran, for the period from 2000 to 2005, gauged in the city at the outskirt of alluvial funneling mountains with an established microclimatic conditions and a diurnal wind regime. This provides a sufficiently severe test for the ANN model with a good predictive capability of 1 year of lead time but without any direct approach to refer the predicted results to local microclimatic conditions. A method is used in this paper to calculate the relative importance of each meteorological input parameters affecting wind speed, showing that air pressure and precipitation are the most and least influential parameters with approximate values of 40 and 10 %, respectively. This gained knowledge corresponds to the local knowledge of the microclimatic and geomorphologic conditions surrounding Tabriz.

  10. Observational constraints on U.S. emissions of climate-active and ozone-depleting trace gases from a tall-tower and aircraft sampling network

    NASA Astrophysics Data System (ADS)

    Montzka, S. A.; Miller, B. R.; Siso, C.; Sweeney, C.; Andrews, A. E.; Karion, A.; Neff, D.; Fischer, M. L.; Higgs, J.

    2010-12-01

    Air samples have been regularly collected at a number of tall tower sites and from aircraft profiling locations across the U.S. and Canada during the past 4 to 5 years. Measurements of approximately 50 trace gases in these samples provide a rich dataset of chemical markers related to urban, industrial, oceanic, biomass burning, fossil-fuel burning, atmospheric mixing, photosynthesis, and soil influences. Anthropogenic emission signals are readily apparent in the halocarbon and hydrocarbon data, upon which this talk will focus. Measured correlations between different halocarbons (especially hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs)) show variations as a function of season that are qualitatively consistent with the expected regional and seasonal patterns of use and emission of these industrially-produced chemicals. In some instances, annual mean correlation slopes between different trace gases are well described by the U.S. EPA Greenhouse Gas Emission Inventories, but for others, large differences are observed. Furthermore, interannual changes in correlation slopes are expected for gases that are being phased out (i.e., HCFCs) compared to those for which emissions may be increasing (i.e., HFCs) in the US. This presentation will focus on the regional, seasonal, and interannual variations in trace gas emissions implied from a straightforward analysis of this extensive measurement record.

  11. Data Quality Assessment Methods for the Eastern Range 915 MHz Wind Profiler Network

    NASA Technical Reports Server (NTRS)

    Lambert, Winifred C.; Taylor, Gregory E.

    1998-01-01

    The Eastern Range installed a network of five 915 MHz Doppler Radar Wind Profilers with Radio Acoustic Sounding Systems in the Cape Canaveral Air Station/Kennedy Space Center area to provide three-dimensional wind speed and direction and virtual temperature estimates in the boundary layer. The Applied Meteorology Unit, staffed by ENSCO, Inc., was tasked by the 45th Weather Squadron, the Spaceflight Meteorology Group, and the National Weather Service in Melbourne, Florida to investigate methods which will help forecasters assess profiler network data quality when developing forecasts and warnings for critical ground, launch and landing operations. Four routines were evaluated in this study: a consensus time period check a precipitation contamination check, a median filter, and the Weber-Wuertz (WW) algorithm. No routine was able to effectively flag suspect data when used by itself. Therefore, the routines were used in different combinations. An evaluation of all possible combinations revealed two that provided the best results. The precipitation contamination and consensus time routines were used in both combinations. The median filter or WW was used as the final routine in the combinations to flag all other suspect data points.

  12. Oriented spray-assisted cooling tower

    SciTech Connect

    Bowman, C.F.

    1995-04-18

    Apparatus useful for heat exchange by evaporative cooling when employed in conjunction with a conventional cooling tower. The arrangement includes a header pipe which is used to divert a portion of the water in the cooling tower supply conduit up stream of the cooling tower to a multiplicity of vertical pipes and spray nozzles which are evenly spaced external to the cooling tower so as to produce a uniform spray pattern oriented toward the central axis of the cooling tower and thereby induce an air flow into the cooling tower which is greater than otherwise achieved. By spraying the water to be cooled towards the cooling tower in a region external to the cooling tower in a manner such that the spray falls just short of the cooling tower basin, the spray does not interfere with the operation of the cooling tower, proper, and the-maximum increase in air velocity is achieved just above the cooling tower basin where it is most effective. The sprayed water lands on a concrete or asphalt apron which extends from the header pipe to the cooling tower basin and is gently sloped towards the cooling tower basin such that the sprayed water drains into the basin. By diverting a portion of the water to be cooled to a multiplicity of sprays external to the cooling tower, thermal performance is improved. 4 figs.

  13. The use of real-time off-site observations as a methodology for increasing forecast skill in prediction of large wind power ramps one or more hours ahead of their impact on a wind plant.

    SciTech Connect

    Martin Wilde, Principal Investigator

    2012-12-31

    ABSTRACT Application of Real-Time Offsite Measurements in Improved Short-Term Wind Ramp Prediction Skill Improved forecasting performance immediately preceding wind ramp events is of preeminent concern to most wind energy companies, system operators, and balancing authorities. The value of near real-time hub height-level wind data and more general meteorological measurements to short-term wind power forecasting is well understood. For some sites, access to onsite measured wind data - even historical - can reduce forecast error in the short-range to medium-range horizons by as much as 50%. Unfortunately, valuable free-stream wind measurements at tall tower are not typically available at most wind plants, thereby forcing wind forecasters to rely upon wind measurements below hub height and/or turbine nacelle anemometry. Free-stream measurements can be appropriately scaled to hub-height levels, using existing empirically-derived relationships that account for surface roughness and turbulence. But there is large uncertainty in these relationships for a given time of day and state of the boundary layer. Alternatively, forecasts can rely entirely on turbine anemometry measurements, though such measurements are themselves subject to wake effects that are not stationary. The void in free-stream hub-height level measurements of wind can be filled by remote sensing (e.g., sodar, lidar, and radar). However, the expense of such equipment may not be sustainable. There is a growing market for traditional anemometry on tall tower networks, maintained by third parties to the forecasting process (i.e., independent of forecasters and the forecast users). This study examines the value of offsite tall-tower data from the WINDataNOW Technology network for short-horizon wind power predictions at a wind farm in northern Montana. The presentation shall describe successful physical and statistical techniques for its application and the practicality of its application in an operational setting. It shall be demonstrated that when used properly, the real-time offsite measurements materially improve wind ramp capture and prediction statistics, when compared to traditional wind forecasting techniques and to a simple persistence model.

  14. Effect of Wind Speed on Aerosol Optical Depth over Remote Oceans, Based on Data from the Maritime Aerosol Network

    NASA Technical Reports Server (NTRS)

    Smirnov, A.; Sayer, A. M.; Holben, B. N.; Hsu, N. C.; Sakerin, S. M.; Macke, A.; Nelson, N. B.; Courcoux, Y.; Smyth, T. J.; Croot, P.; Quinn, P. K.; Sciare, J.; Gulev, S. K.; Piketh, S.; Losno, R.; Kinne, S.; Radionov, V. F.

    2012-01-01

    The Maritime Aerosol Network (MAN) has been collecting data over the oceans since November 2006. The MAN archive provides a valuable resource for aerosol studies in maritime environments. In the current paper we investigate correlations between ship-borne aerosol optical depth (AOD) and near-surface wind speed, either measured (onboard or from satellite) or modeled (NCEP). According to our analysis, wind speed influences columnar aerosol optical depth, although the slope of the linear regression between AOD and wind speed is not steep (approx. 0.004 - 0.005), even for strong winds over 10m/s. The relationships show significant scatter (correlation coefficients typically in the range 0.3 - 0.5); the majority of this scatter can be explained by the uncertainty on the input data. The various wind speed sources considered yield similar patterns. Results are in good agreement with the majority of previously published relationships between surface wind speed and ship-based or satellite-based AOD measurements. The basic relationships are similar for all the wind speed sources considered; however, the gradient of the relationship varies by around a factor of two depending on the wind data used

  15. Parametric study of tornado-type wind-energy systems

    SciTech Connect

    Ayad, S.S.

    1981-10-01

    The tornado-type wind energy system uses the pressure drop created by an intense vortex. The vortex is generated in a tower mounted at the turbine exit. The tower serves as a low pressure exhaust for the turbine. In a previous work, the author provided a numerical solution, using the two-equation (k-epsilon) turbulence model, of the tower flow with a uniform wind flow. Results compared favorably with measured values of pressure and showed a turbine diameter of approx. 0.4 times that of the tower to be optimum. In the present work, the author provides results to show the effects of embedding the tower in an atmospheric boundary layer, varying the tower height to diameter ratio, and varying tower diameter using the same system geometry and approach flow conditions. The results indicate a reduction of approx. 28% in power output

  16. Wind Tunnel Construction 

    E-print Network

    Unknown

    2011-08-17

    about $375. Advantages and disadvantages of solar and wind energy Some advantages and disadvantages for using solar or wind energy are presented in Table 1. The main advantage of using renewable energy is that there is no energy cost to pump the wa t e r... tall; otherwise, the towers become very expensive. A windmil?s pumping output is affected by thre factors: wind speed, wheel or blade diame- t e r, and the diameter of the cylinder (Table 3). Wind speed has an important effect on the pumping output...

  17. Observing wind, aerosol particles, cloud and precipitation: Finland's new ground-based remote-sensing network

    NASA Astrophysics Data System (ADS)

    Hirsikko, A.; O'Connor, E. J.; Komppula, M.; Korhonen, K.; Pfüller, A.; Giannakaki, E.; Wood, C. R.; Bauer-Pfundstein, M.; Poikonen, A.; Karppinen, T.; Lonka, H.; Kurri, M.; Heinonen, J.; Moisseev, D.; Asmi, E.; Aaltonen, V.; Nordbo, A.; Rodriguez, E.; Lihavainen, H.; Laaksonen, A.; Lehtinen, K. E. J.; Laurila, T.; Petäjä, T.; Kulmala, M.; Viisanen, Y.

    2014-05-01

    The Finnish Meteorological Institute, in collaboration with the University of Helsinki, has established a new ground-based remote-sensing network in Finland. The network consists of five topographically, ecologically and climatically different sites distributed from southern to northern Finland. The main goal of the network is to monitor air pollution and boundary layer properties in near real time, with a Doppler lidar and ceilometer at each site. In addition to these operational tasks, two sites are members of the Aerosols, Clouds and Trace gases Research InfraStructure Network (ACTRIS); a Ka band cloud radar at Sodankylä will provide cloud retrievals within CloudNet, and a multi-wavelength Raman lidar, PollyXT (POrtabLe Lidar sYstem eXTended), in Kuopio provides optical and microphysical aerosol properties through EARLINET (the European Aerosol Research Lidar Network). Three C-band weather radars are located in the Helsinki metropolitan area and are deployed for operational and research applications. We performed two inter-comparison campaigns to investigate the Doppler lidar performance, compare the backscatter signal and wind profiles, and to optimize the lidar sensitivity through adjusting the telescope focus length and data-integration time to ensure sufficient signal-to-noise ratio (SNR) in low-aerosol-content environments. In terms of statistical characterization, the wind-profile comparison showed good agreement between different lidars. Initially, there was a discrepancy in the SNR and attenuated backscatter coefficient profiles which arose from an incorrectly reported telescope focus setting from one instrument, together with the need to calibrate. After diagnosing the true telescope focus length, calculating a new attenuated backscatter coefficient profile with the new telescope function and taking into account calibration, the resulting attenuated backscatter profiles all showed good agreement with each other. It was thought that harsh Finnish winters could pose problems, but, due to the built-in heating systems, low ambient temperatures had no, or only a minor, impact on the lidar operation - including scanning-head motion. However, accumulation of snow and ice on the lens has been observed, which can lead to the formation of a water/ice layer thus attenuating the signal inconsistently. Thus, care must be taken to ensure continuous snow removal.

  18. 30 WS North Base Wind Study

    NASA Technical Reports Server (NTRS)

    Wheeler, Mark

    2011-01-01

    The 30 Weather Squadron (30 WS) is concerned about strong winds observed at their northern towers without advance warning. They state that terrain influences along the extreme northern fringes of Vandenberg Air Force Base (VAFB) make it difficult for forecasters to issue timely and accurate high wind warnings for northeasterly wind events. These events tend to occur during the winter or early spring when they are under the influence of the Great Basin high pressure weather regime. The Launch Weather Officers (LWOs) have seen these rapid wind increases in the current northern Towers 60, 70 and 71 in excess of their 35 kt operational warning threshold. For this task, the 30 WS requested the Applied Meteorology Unit (AMU) analyze data from days when these towers reported winds in excess of 35 kt and determine if there were any precursors in the observations that would allow the LWOs to better forecast and warn their operational customers for these wind events. The 30 WS provided wind tower data for the cool season (October - March) from the period January 2004-March 20 IO. The AMU decoded and evaluated the wind tower data for 66 days identified by the 30 WS as having high-wind events. Out of the 66 event days, only 30 had wind speed observations of > or =35 kt from at least one of the three northern towers. The AMU analyzed surface and upper air charts to determine the synoptic conditions for each event day along with tower peak wind speed and direction time series and wind rose charts for all 30 event days. The analysis revealed a trend on all event days in which the tower winds shifted to the northeast for a period of time before the first recorded > or =35 kt wind speed. The time periods for the 30 event days ranged from 20 minutes to several hours, with a median value of 110 minutes. This trend, if monitored, could give the 30 WS forecasters a precursor to assist in issuing an operational warning before a high wind event occurs. The AMU recommends developing a high-wind alert capability for VAFB using a local mesoscale model to forecast these wind events. The model should incorporate all of the VAFB local data sets and have a forecast capability of between 2 to 24 hours. Such a model would allow the meteorologists at VAFB to alert the operational customers of high wind events in a timely manner so protective action could be taken.

  19. Impact of SCIG and DFIG Type Wind Turbine on the Stability of Distribution Networks: static and dynamic

    E-print Network

    Pota, Himanshu Roy

    benefits [2], [3]. The effect of control modes of excitation systems for synchronous machines based DG is discussed in [4]. It is shown that, when the synchronous machine based DG is equipped with a voltage fed induction generator (DFIG) type wind turbine in distribution networks. The analysis is carried out

  20. Thin film sensor network for condition assessment of wind turbine blades

    NASA Astrophysics Data System (ADS)

    Laflamme, Simon; Saleem, Hussam; Venkatesh, Chinde; Vaidya, Umesh; Sarkar, Partha; Sauder, Heather

    2014-03-01

    Existing sensing solutions facilitating continuous condition assessment of wind turbine blades are limited by a lack of scalability and clear link signal-to-prognosis. With recent advances in conducting polymers, it is now possible to deploy networks of thin film sensors over large areas, enabling low cost sensing of large-scale systems. Here, we propose to use a novel sensing skin consisting of a network of soft elastomeric capacitors (SECs). Each SEC acts as a surface strain gage transducing local strain into measurable changes in capacitance. Using surface strain data facilitates the extraction of physics-based features from the signals that can be used to conduct condition assessment. We investigate the performance of an SEC network at detecting damages. Diffusion maps are constructed from the time series data, and changes in point-wise diffusion distances evaluated to determine the presence of damage. Results are benchmarked against time-series data produced from off-the-shelf resistive strain gauges. This paper presents data from a preliminary study. Results show that the SECs are promising, but the capability to perform damage detection is currently reduced by the presence of parasitic noise in the signal.

  1. Commissioning through "EDF Tower" construction

    E-print Network

    Rouillot, M.

    2004-01-01

    michel rouillot -architecte d.p.l.g. CommissioningCommissioningthrough through ??EDF TowerEDF Tower? construction? construction by Michel Rouillot Architect D.P.L.G. michel rouillot -architecte d.p.l.g. What is a building project ? michel rouillot... -architecte d.p.l.g. A spatial answerfor a work structure michel rouillot -architecte d.p.l.g. A very strong relationship between many building participants michel rouillot -architecte d.p.l.g. The production of the buildingThe production of the building...

  2. Improving Process Cooling Tower Eddiciency 

    E-print Network

    Turpish, W.

    2013-01-01

    of the Thrity-Fifth Industrial Energy Technology Conference New Orleans, LA. May 21-24, 2013 7 Improving Cooling Tower Efficiency ? Two Improvements in Capacity/Performance 1. Filtration for water quality control Side stream filtration Make up water quality...-Fifth Industrial Energy Technology Conference New Orleans, LA. May 21-24, 2013 16 Improving Cooling Tower Efficiency Make up water softening Effects of hard make up water ?Softening (and filtration) allow increased cycles. ESL-IE-13-05-08 Proceedings...

  3. F-BF Skeleton Tower

    NSDL National Science Digital Library

    This is a task from the Illustrative Mathematics website that is one part of a complete illustration of the standard to which it is aligned. Each task has at least one solution and some commentary that addresses important asects of the task and its potential use. Here are the first few lines of the commentary for this task: How many cubes are needed to build this tower? How many cubes are needed to build a tower like this, but $12$ cubes high? Justify your reasoning. How w...

  4. Aerodynamic interference between two Darrieus wind turbines

    Microsoft Academic Search

    P. R. Schatzle; P. C. Klimas; H. R. Spahr

    1981-01-01

    The effect of aerodynamic interference on the performance of two curved bladed Darrieus-type vertical axis wind turbines has been calculated using a vortex\\/lifting line aerodynamic model. The turbines have a tower-to-tower separation distance of 1.5 turbine diameters, with the line of turbine centers varying with respect to the ambient wind direction. The effects of freestream turbulence were neglected. For the

  5. Aerodynamic interference between two Darrieus wind turbines

    Microsoft Academic Search

    P. R. Schatzle; P. C. Klimas; H. R. Spahr

    1980-01-01

    The effect of aerodynamic interference on the performance of two curved bladed Darrieus-type vertical axis wind turbines has been calculated using a vortex\\/lifting line aerodynamic model. The turbines have a tower-to-tower separation distance of 1.5 turbine diameters, with the line of turbine centers varying with respect to the ambient wind direction. The effects of freestream turbulence were neglected. For the

  6. MODULAR REPRESENTATIONS FOR MODULAR TOWERS. Darren Semmen

    E-print Network

    Fried, Michael

    MODULAR REPRESENTATIONS FOR MODULAR TOWERS. by Darren Semmen Contents 1. The universal p. Asymptotics of the p-Frattini modules Mn . . . . . . . . . . . . . . . . . . . . . . . 10 5. Modular towers modular representation theory, the key tool being a categorical equivalence due to Gruenberg

  7. Networked Control System Wind Tunnel (NCSWT)-An evaluation tool for networked multi-agent systems

    E-print Network

    Koutsoukos, Xenofon D.

    systems (NCS). NCS are deployed in many environ- ments subject to realistic, complex network interactions, so evaluation of NCS is crucial to ensuring that NCS function as intended. Given the varied nature of NCS, it is appro- priate to use a heterogenous simulation environment to cap- ture the dynamics

  8. Knowledge base for the systematic design of wet cooling towers. Part I: Selection and tower characteristics

    Microsoft Academic Search

    K Kant

    1996-01-01

    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

  9. Long-term observations of meteor winds by the SuperDARN HF radar network

    NASA Astrophysics Data System (ADS)

    Talaat, Elsayed; Ruohoniemi, J. Michael; McCubbin, Elizabeth; Azeem, S. M. Irfan; Greenwald, Raymond

    2012-07-01

    The HF Super Dual Auroral Radar Network (SuperDARN) radars detect a category of backscatter that is due to meteor trails in the mesosphere. The motion of the neutral atmosphere can be inferred and applied to the study of atmospheric tides and planetary waves. The current configurations of longitudinal radar chains in the northern and southern hemispheres have accumulated mesospheric wind measurements continuously since the last solar cycle maximum while the archives of some of the radars span more than a solar cycle. We have analyzed the occurrence of mesospheric tides, planetary wave, and gravity wave activity in the meteor wind data over long periods at several radar stations in both hemispheres. Understanding the behavior of planetary waves and tides is not only crucial to characterizing mesopause variability but also transport in the mesosphere and lower thermosphere. in the mesosphere and lower thermosphere. We examine the seasonal and inter-annual variations of the diurnal, semidiurnal and terdiurnal tides, and planetary waves. We find connections to the quasi-biennial oscillation and to sudden stratospheric warming (SSW) events. We present examples of intensified planetary wave activity that occurred during SSWs. Additionally, we examine the variability in tidal and planetary wave activity over the past solar cycle and correlations with lower atmospheric phenomena and other datasets.

  10. Accurate Monitoring and Fault Detection in Wind Measuring Devices through Wireless Sensor Networks

    PubMed Central

    Khan, Komal Saifullah; Tariq, Muhammad

    2014-01-01

    Many wind energy projects report poor performance as low as 60% of the predicted performance. The reason for this is poor resource assessment and the use of new untested technologies and systems in remote locations. Predictions about the potential of an area for wind energy projects (through simulated models) may vary from the actual potential of the area. Hence, introducing accurate site assessment techniques will lead to accurate predictions of energy production from a particular area. We solve this problem by installing a Wireless Sensor Network (WSN) to periodically analyze the data from anemometers installed in that area. After comparative analysis of the acquired data, the anemometers transmit their readings through a WSN to the sink node for analysis. The sink node uses an iterative algorithm which sequentially detects any faulty anemometer and passes the details of the fault to the central system or main station. We apply the proposed technique in simulation as well as in practical implementation and study its accuracy by comparing the simulation results with experimental results to analyze the variation in the results obtained from both simulation model and implemented model. Simulation results show that the algorithm indicates faulty anemometers with high accuracy and low false alarm rate when as many as 25% of the anemometers become faulty. Experimental analysis shows that anemometers incorporating this solution are better assessed and performance level of implemented projects is increased above 86% of the simulated models. PMID:25421739

  11. Optimal Inflatable Space Towers of High Height

    Microsoft Academic Search

    Alexander Bolonkin

    2002-01-01

    Author provides theory and computations for building inflatable space towers up to a hundred km in height. These towers can be used for tourism; scientific observation of space, earth's surface, weather, top atmosphere, as well as for radio, television, and communication transmissions. These towers can also be used to launch space ships and Earth satellites. These projects are not expensive

  12. Unfolding Manhattan Towers 1 Mirela Damian a

    E-print Network

    O'Rourke, Joseph

    Unfolding Manhattan Towers 1 Mirela Damian a and Robin Flatland b and Joseph O'Rourke c,2 a shape class we call Manhattan Towers, to a nonoverlapping planar orthogonal polygon. The algorithm cuts we pursue in this paper, on a class of shapes not previously considered. We define "Manhattan Tower

  13. Adaptation of amoebae to cooling tower biocides

    Microsoft Academic Search

    S. Srikanth; S. G. Berk

    1994-01-01

    Adaptation of amoebae to four cooling tower Biocides, which included a thiocarbamate compound, tributyltin neodecanoate mixed with quaternary ammonium compounds (TBT\\/QAC), another QAC alone, and an isothiazolin derivative, was studied. Previously we found that amoebae isolated from waters of cooling towers were more resistant to cooling tower biocides than amoebae from other habitats. Acanthamoeba hatchetti and Cochliopodium bilimbosum, obtained from

  14. Costs, laws spur cooling tower sales

    Microsoft Academic Search

    Minerbrook

    1977-01-01

    Industrial cooling towers have had a rapid growth in sales after legislation was passed to prevent companies from disposing of thermal pollutants in waterways and after fuel prices began rising. Mechanical draft towers that circulate air with fans and pumps are used more than natural draft towers. Industries with extensive process heat, those with limited water supplies, and those with

  15. 76 FR 490 - Marking Meteorological Evaluation Towers

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-05

    ...color, portability of these towers, their placement in rural...the safety impacts of these towers on low-level agricultural...concerns of the aerial application industry. The NAAA suggested safety...The FAA recommends that the towers be painted in accordance...

  16. An integrated modeling method for wind turbines

    NASA Astrophysics Data System (ADS)

    Fadaeinedjad, Roohollah

    To study the interaction of the electrical, mechanical, and aerodynamic aspects of a wind turbine, a detailed model that considers all these aspects must be used. A drawback of many studies in the area of wind turbine simulation is that either a very simple mechanical model is used with a detailed electrical model, or vice versa. Hence the interactions between electrical and mechanical aspects of wind turbine operation are not accurately taken into account. In this research, it will be shown that a combination of different simulation packages, namely TurbSim, FAST, and Simulink can be used to model the aerodynamic, mechanical, and electrical aspects of a wind turbine in detail. In this thesis, after a review of some wind turbine concepts and software tools, a simulation structure is proposed for studying wind turbines that integrates the mechanical and electrical components of a wind energy conversion device. Based on the simulation structure, a comprehensive model for a three-bladed variable speed wind turbine with doubly-fed induction generator is developed. Using the model, the impact of a voltage sag on the wind turbine tower vibration is investigated under various operating conditions such as power system short circuit level, mechanical parameters, and wind turbine operating conditions. It is shown how an electrical disturbance can cause more sustainable tower vibrations under high speed and turbulent wind conditions, which may disrupt the operation of pitch control system. A similar simulation structure is used to model a two-bladed fixed speed wind turbine with an induction generator. An extension of the concept is introduced by adding a diesel generator system. The model is utilized to study the impact of the aeroelastic aspects of wind turbine (i.e. tower shadow, wind shears, yaw error, turbulence, and mechanical vibrations) on the power quality of a stand-alone wind-diesel system. Furthermore, an IEEE standard flickermeter model is implemented in a Simulink environment to study the flicker contribution of the wind turbine in the wind-diesel system. By using a new wind power plant representation method, a large wind farm (consisting of 96 fixed speed wind turbines) is modelled to study the power quality of wind power system. The flicker contribution of wind farm is also studied with different wind turbine numbers, using the flickermeter model. Keywords. Simulink, FAST, TurbSim, AreoDyn, wind energy, doubly-fed induction generator, variable speed wind turbine, voltage sag, tower vibration, power quality, flicker, fixed speed wind turbine, wind shear, tower shadow, and yaw error.

  17. A COOLING SYSTEM FOR BUIDINGS USING WIND ENERGY

    E-print Network

    A COOLING SYSTEM FOR BUIDINGS USING WIND ENERGY Hamid Daiyan Islamic Azad University - Semnan in dray land, and only uses wind energy for conditioning. It technologies date back over 1000 years. Wind Branch, Iran hamid.daiyan@semnaniau.ac.ir Abstract In Iranian historical architecture wind tower is used

  18. Wind-Wildlife Impacts Literature Database (WILD)(Fact Sheet)

    SciTech Connect

    Not Available

    2015-01-01

    The Wind-Wildlife Impacts Literature Database (WILD), developed and maintained by the National Wind Technology Center (NWTC) at the National Renewable Energy Laboratory (NREL), is comprised of over 1,000 citations pertaining to the effects of land-based wind, offshore wind, marine and hydrokinetic, power lines, and communication and television towers on wildlife.

  19. Quantifying the hurricane risk to offshore wind turbines

    E-print Network

    Jaramillo, Paulina

    Quantifying the hurricane risk to offshore wind turbines Stephen Rosea , Paulina Jaramilloa,1. Turbine tower buckling has been observed in typhoons, but no offshore wind turbines have yet been built be destroyed by hurricanes in an offshore wind farm. We apply this model to estimate the risk to offshore wind

  20. Cooling towers: Energy conservation strategy

    Microsoft Academic Search

    Burger

    1984-01-01

    This article proposes that practically all cooling towers can be upgraded to perform at higher levels of efficiency, providing a rapid, cost-effective payback. Topics considered include air handling, water distribution, heat transfer surfaces, and the function of lower temperatures. Case histories are presented of an anhydrous ammonia plant, a gasoline petrochemical plant, and a power generating plant. It is shown

  1. The solar towers of Chankillo

    E-print Network

    Sparavigna, Amelia Carolina

    2012-01-01

    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.

  2. EPA'S COOLING TOWER PLUME RESEARCH

    EPA Science Inventory

    A comprehensive review is made of EPA's cooling tower plume research program with particular attention to plume modeling. The research began in 1969 with a modest effort to define the problem and continued through a multidisciplinary research project at a site where a single-cell...

  3. New developments in cooling towers

    Microsoft Academic Search

    Bartz

    1994-01-01

    This article examines developments in power plant cooling systems which include advanced evaporative and dry cooling technologies. Potentials are seen for fabric structures. Developments in cooling tower technology have quietly gained momentum in recent years. Now more choices stand ready to answer just about every need in the power generation industry. As an example, one of the most active areas

  4. Occupational Licensing of Tower Climbers

    Microsoft Academic Search

    Michael S. Landa

    There is a renewed push for occupational licensing in the tower industry; proponents cite improved quality, improved safety and a number of other benefits that would result from licensing. The problem is previous and exhaustive occupational licensing research has proven these \\

  5. IEEE TRANSACTIONS ON ENERGY CONVERSION, VOL. 21, NO. 3, SEPTEMBER 2006 717 Simulation Model of Wind Turbine 3p Torque

    E-print Network

    Lehn, Peter W.

    Turbine 3p Torque Oscillations due to Wind Shear and Tower Shadow Dale S. L. Dolan, Student Member, IEEE quality issues, the dynamic torque generated by the blades of a wind turbine must be represented turbine including the effects of wind shear and tower shadow. The comprehensive model includes turbine

  6. Distributed Array of GPS Receivers for 3D Wind Profile Determination in Wind Farms

    E-print Network

    Gao, Grace Xingxin

    transceivers and pitot tubes are equipped in wind speed sensing payloads, which are lifted by aerostats. The 3D. Traditional wind sensing is done through the construction of large meteorological masts with cup anemometers. Alternative wind sensing techniques entail alternative remote sensing methods to tower-based cup anemometers

  7. Wind for Schools Project Power System Brief, Wind Powering America Fact Sheet Series

    SciTech Connect

    Baring-Gould, I.

    2009-05-01

    Wind Powering America's (WPA's) Wind for Schools project uses a basic system configuration for each school project. The system incorporates a single SkyStream wind turbine, a 70-ft guyed tower, disconnect boxes at the base of the turbine and at the school, and an interconnection to the school's electrical system. This document provides a detailed description of each system component.

  8. Statement of Interest in a New Project, in response to PPARC call of April 26th FHIRN: A next-generation radio network for exploring the 3-dimensional solar wind

    E-print Network

    -generation radio network for exploring the 3-dimensional solar wind Future Heliospheric Imaging Radio Network The solar wind is a supersonically-expanding extension of the solar atmosphere into interplanetary space of the solar wind controls the structure of the entire heliosphere, but direct measurements of the 3D solar

  9. Ozone Treatment For Cooling Towers

    NASA Technical Reports Server (NTRS)

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

    1990-01-01

    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.

  10. DETECTION OF CENTRIPETAL HEAT-ISLAND CIRCULATIONS FROM TOWER DATA IN ST. LOUIS

    EPA Science Inventory

    Hourly averaged meteorological data gathered by a 25-tower network about St. Louis during 1976 are used in a search for centripetal circulations generated by the urban heat island. Considering data collected when the network resultant speed was less than 1.5 m/s, two data classes...

  11. Damage detection in carbon composite material typical of wind turbine blades using auto-associative neural networks

    NASA Astrophysics Data System (ADS)

    Dervilis, N.; Barthorpe, R. J.; Antoniadou, I.; Staszewski, W. J.; Worden, K.

    2012-04-01

    The structure of a wind turbine blade plays a vital role in the mechanical and structural operation of the turbine. As new generations of offshore wind turbines are trying to achieve a leading role in the energy market, key challenges such as a reliable Structural Health Monitoring (SHM) of the blades is significant for the economic and structural efficiency of the wind energy. Fault diagnosis of wind turbine blades is a "grand challenge" due to their composite nature, weight and length. The damage detection procedure involves additional difficulties focused on aerodynamic loads, environmental conditions and gravitational loads. It will be shown that vibration dynamic response data combined with AANNs is a robust and powerful tool, offering on-line and real time damage prediction. In this study the features used for SHM are Frequency Response Functions (FRFs) acquired via experimental methods based on an LMS system by which identification of mode shapes and natural frequencies is accomplished. The methods used are statistical outlier analysis which allows a diagnosis of deviation from normality and an Auto-Associative Neural Network (AANN). Both of these techniques are trained by adopting the FRF data for normal and damage condition. The AANN is a method which has not yet been widely used in the condition monitoring of composite materials of blades. This paper is trying to introduce a new scheme for damage detection, localisation and severity assessment by adopting simple measurements such as FRFs and exploiting multilayer neural networks and outlier novelty detection.

  12. Optical sampling of the flux tower footprint

    NASA Astrophysics Data System (ADS)

    Gamon, J. A.

    2015-03-01

    The purpose of this review is to address the reasons and methods for conducting optical remote sensing within the flux tower footprint. Fundamental principles and conclusions gleaned from over two decades of proximal remote sensing at flux tower sites are reviewed. An organizing framework is the light-use efficiency (LUE) model, both because it is widely used, and because it provides a useful theoretical construct for integrating optical remote sensing with flux measurements. Multiple ways of driving this model, ranging from meteorological measurements to remote sensing, have emerged in recent years, making it a convenient conceptual framework for comparative experimental studies. New interpretations of established optical sampling methods, including the Photochemical Reflectance Index (PRI) and Solar-Induced Fluorescence (SIF), are discussed within the context of the LUE model. Multi-scale analysis across temporal and spatial axes is a central theme, because such scaling can provide links between ecophysiological mechanisms detectable at the level of individual organisms and broad patterns emerging at larger scales, enabling evaluation of emergent properties and extrapolation to the flux footprint and beyond. Proper analysis of sampling scale requires an awareness of sampling context that is often essential to the proper interpretation of optical signals. Additionally, the concept of optical types, vegetation exhibiting contrasting optical behavior in time and space, is explored as a way to frame our understanding of the controls on surface-atmosphere fluxes. Complementary NDVI and PRI patterns across ecosystems are offered as an example of this hypothesis, with the LUE model and light-response curve providing an integrating framework. We conclude that experimental approaches allowing systematic exploration of plant optical behavior in the context of the flux tower network provides a unique way to improve our understanding of environmental constraints and ecophysiological function. In addition to an enhanced mechanistic understanding of ecosystem processes, this integration of remote sensing with flux measurements offers many rich opportunities for upscaling, satellite validation, and informing practical management objectives ranging form assessing ecosystem health and productivity to quantifying biospheric carbon sequestration.

  13. Performance of tornado-type wind turbines with radial inflow supply

    SciTech Connect

    Hsu, C.T.; Ide, H.

    1982-09-01

    Wind tunnel tests were conducted for the performance of tornado-type wind turbines with radial inflow supply from the incoming wind. It was shown that the radial inflow supply was necessary for intensifying a vortex in the wind collecting tower and, consequently, for enhancing the power efficiencies. A maximum power efficiency of 3.8 was obtained for a circular-shaped tower as compared to the value of 0.4 for the conventional windmills.

  14. 24 m meteorological tower data report period: January through December, 1995

    SciTech Connect

    Freeman, D.; Bowen, J.B.; Egami, R.; Coulombe, W.; Crow, D.; Cristani, B.; Schmidt, S.

    1997-12-01

    This report was prepared by the Desert Research Institute (DRI) for the US Department of Energy (DOE). It summarizes meteorological data collected at the 24 meter tower at the Nevada Test Site Hazardous Material Spill Center (HAZMAT) located at Frenchman Flat near Mercury, Nevada, approximately 75 miles northwest of Las Vegas, Nevada. The tower was originally installed in July, 1993 to characterize baseline conditions for an EPA sponsored experimental research program at the HAZMAT. A previous report reported monitoring results for 1994. This report presents results of the monitoring for January--December, 1995, providing: a status of the measurement systems (including any quality assurance activities) during the report period and a summary of the meteorological conditions at the HAZMAT during the report period. The scope of the report is limited to summary data analyses and does not include extensive meteorological analysis. The tower was instrumented at 8 levels. Wind speed, wind direction, and temperature were measured at all 8 levels. Relative humidity was measured at 3 levels. Solar and net radiation were measured at 2 meters above the ground. Barometric pressure was measured at the base of the tower and soil temperature was measured near the base of the tower.

  15. 24 m meteorological tower data report period: January through December, 1996

    SciTech Connect

    Freeman, D.; Bowen, J.; Egami, R.; Coulombe, W.; Crow, D.; Cristani, B.; Schmidt, S.

    1997-12-01

    This report was prepared by the Desert Research Institute (DRI) for the US Department of Energy (DOE). It summarizes meteorological data collected at the 24 meter tower at the Nevada Test Site Hazardous Material Spill Center (HAZMAT) located at Frenchman Flat near Mercury, Nevada, approximately 75 miles northwest of Las Vegas, Nevada. The tower was originally installed in July, 1993 to characterize baseline conditions for an EPA sponsored experimental research program at the HAZMAT. This report presents results of the monitoring for January--December, 1996, providing: a status of the measurement systems during the report period and a summary of the meteorological conditions at the HAZMAT during the report period. The scope of the report is limited to summary data analyses and does not include extensive meteorological analysis. The tower was instrumented at 8 levels. Wind speed, wind direction, and temperature were measured at all 8 levels. Relative humidity was measured at 3 levels. Solar and net radiation were measured at 2 meters above the ground. Barometric pressure was measured at the base of the tower and soil temperature was measured near the base of the tower.

  16. NON-DIVERGENT WIND ANALYSIS ALGORITHM FOR THE ST. LOUIS RAPS (REGIONAL AIR POLLUTION STUDY) NETWORK

    EPA Science Inventory

    An objective wind analysis algorithm capable of producing non-divergent wind fields at up to ten levels in the atmospheric boundary layer for St. Louis, Missouri is described. Wind data collected during the St. Louis Regional Air Pollution Study (RAPS) and averaged over 15-minute...

  17. Atmospheric LIDAR Provides Insight into Land Surface-Atmosphere Exchange at AmeriFlux Towers

    NASA Astrophysics Data System (ADS)

    Wharton, S.; Osuna, J. L.; Newman, J.; Falk, M.; Baldocchi, D. D.; Bible, K.

    2012-12-01

    Lower levels of the planetary boundary layer (PBL) tend towards stable conditions at night with turbulent transfer of mass and energy exchange driven solely by mechanically forced turbulence, either from frictional forces near the ground or at the top of the plant canopy or from "top-down" forced intermittent bursts of turbulence generated from wind shear aloft. Nighttime mixing is further complicated by variable topography which creates complex wind flows including strong, along-valley-axis flows (wind direction shifts) and gravity-driven, mountain-valley flows that are particularly strong at night. Our estimates of terrestrial carbon sink or source magnitudes come primarily from flux towers which measure CO2, H2O, and energy exchange between the vegetated surface and the atmosphere with the eddy covariance technique. Flux towers are usually equipped with instrumentation only to the top of the plant canopy or a few meters above, although in reality, nocturnal wind shear can be strong well above the canopy and produce turbulent eddies which intermittently penetrate the canopy. The structures and drivers of these "top-down" forced events are currently being missed at most flux towers due to lack of instrumentation above the canopy. Here, we present over 800 hours of wind flow observations above two tree canopies for understanding nighttime turbulent transfer. Measurements of wind speed, direction and turbulence were taken with a Laser Detection and Ranging (LIDAR) instrument, co-located at the Tonzi AmeriFlux tower, California and the Wind River AmeriFlux tower, Washington. LIDAR provided high-resolution vertical profiles of wind shear and turbulence up to 200 m above the surface. To assess the contribution of turbulent transport to net ecosystem exchange, we assume that the efficiency of turbulence to transport mass and energy can be represented by the magnitude of turbulent kinetic energy (TKE). Although there are limitations to calculating accurate turbulence measurements from LIDAR, as will be discussed, LIDAR does provide observations well above the canopy for identifying drivers of "top-down" forced turbulence. Here, we show evidence of these intermittent turbulent bursts and identify times when they penetrate the plant canopy and influence CO2 exchange. At the Tonzi AmeriFlux tower, we also show evidence of advective flows driven by complex terrain to the east. The contribution of advective terms to CO2 exchange is often ignored in the carbon flux budget although we provide evidence that it should be considered even at sites with gentle local terrain. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  18. Optimal operation management of fuel cell/wind/photovoltaic power sources connected to distribution networks

    NASA Astrophysics Data System (ADS)

    Niknam, Taher; Kavousifard, Abdollah; Tabatabaei, Sajad; Aghaei, Jamshid

    2011-10-01

    In this paper a new multiobjective modified honey bee mating optimization (MHBMO) algorithm is presented to investigate the distribution feeder reconfiguration (DFR) problem considering renewable energy sources (RESs) (photovoltaics, fuel cell and wind energy) connected to the distribution network. The objective functions of the problem to be minimized are the electrical active power losses, the voltage deviations, the total electrical energy costs and the total emissions of RESs and substations. During the optimization process, the proposed algorithm finds a set of non-dominated (Pareto) optimal solutions which are stored in an external memory called repository. Since the objective functions investigated are not the same, a fuzzy clustering algorithm is utilized to handle the size of the repository in the specified limits. Moreover, a fuzzy-based decision maker is adopted to select the ‘best' compromised solution among the non-dominated optimal solutions of multiobjective optimization problem. In order to see the feasibility and effectiveness of the proposed algorithm, two standard distribution test systems are used as case studies.

  19. Robust Fault Detection of Wind Energy Conversion Systems Based on Dynamic Neural Networks

    PubMed Central

    Talebi, Nasser; Sadrnia, Mohammad Ali; Darabi, Ahmad

    2014-01-01

    Occurrence of faults in wind energy conversion systems (WECSs) is inevitable. In order to detect the occurred faults at the appropriate time, avoid heavy economic losses, ensure safe system operation, prevent damage to adjacent relevant systems, and facilitate timely repair of failed components; a fault detection system (FDS) is required. Recurrent neural networks (RNNs) have gained a noticeable position in FDSs and they have been widely used for modeling of complex dynamical systems. One method for designing an FDS is to prepare a dynamic neural model emulating the normal system behavior. By comparing the outputs of the real system and neural model, incidence of the faults can be identified. In this paper, by utilizing a comprehensive dynamic model which contains both mechanical and electrical components of the WECS, an FDS is suggested using dynamic RNNs. The presented FDS detects faults of the generator's angular velocity sensor, pitch angle sensors, and pitch actuators. Robustness of the FDS is achieved by employing an adaptive threshold. Simulation results show that the proposed scheme is capable to detect the faults shortly and it has very low false and missed alarms rate. PMID:24744774

  20. Cooling Towers, The Neglected Energy Resource

    E-print Network

    Burger, R.

    1985-01-01

    unifor- mity will improve the tower's performance. Counterflow towers with spray systems can be greatly improved by installing the new square spray ABS practically non-clogging nozzles. An added advantage of this newer type nozzle... non-clogging nozzles. Figure 5 - By changing 388 small orifice nozzles to 36 non-clogging square spray type and installing cellular fill, 5°F colder water was obtained. This chart illustrates the rapid payback for converting the tower, illustrated...

  1. INL Wind Farm Project Description Document

    SciTech Connect

    Gary Siefert

    2009-07-01

    The INL Wind Farm project proposes to install a 20 MW to 40 MW wind farm on government property, consisting of approximately ten to twenty full-sized (80-meter hub height) towers with 2 MW turbines, and access roads. This includes identifying the optimal turbine locations, building access roads, and pouring the tower foundations in preparation for turbine installation. The project successfully identified a location on INL lands with commercially viable wind resources (i.e., greater than 11 mph sustained winds) for a 20 to 40 MW wind farm. Additionally, the proposed Wind Farm was evaluated against other General Plant Projects, General Purpose Capital Equipment projects, and Line Item Construction Projects at the INL to show the relative importance of the proposed Wind Farm project.

  2. Optimal Inflatable Space Towers of High Height

    NASA Astrophysics Data System (ADS)

    Bolonkin, Alexander

    2002-01-01

    Author provides theory and computations for building inflatable space towers up to a hundred km in height. These towers can be used for tourism; scientific observation of space, earth's surface, weather, top atmosphere, as well as 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. Towers can be built using present technology. 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 this tower consists a small engine (used only for friction compensation) located at the earth's surface. The tower is separated into sections and has special protection mechanism in case of a damage. Problems involving security, control, repair, and stability of the proposed towers are addressed in subsequent publications. The author is prepared to discuss these and other problems with serious organizations desiring to research and develop these projects.

  3. Optimal inflatable space towers of high height

    NASA Astrophysics Data System (ADS)

    Bolonkin, A.

    Author suggested, developed theory, and computed some projects of an optimal inflatable space tower of the heights some hundreds km. These towers can be used for tourism, scientist observation of space, Earth surface, Earth weather, Earth top atmosphere, and for radio, TV, communication transmissions. These towers can be used for launching of the space ships and Earth s atellites. The computed projects not expensive, do not request rockets. They need only in thin strong films composed from the artificial fibers and fabricated by a current industry. Towers can be built by a current technology. Towers can be explored (for tourism, communication, etc.) in a time of the construction process and give a profit, self- financing for further constriction. They can permanent increase their height. The tower design does not request a work at the high altitudes. All construction works will be making at the Earth surface. Author suggests the transport system for this tower of a high capability, which does not request a power energy issue. The small engine (only for a friction compensation) is located at the Earth surface. The tower is separated on sections and has a special protection of a case of a damage. It is considered also the problems of security, control, repair, etc. of the suggested towers. The author has also solved additional problems, which appear in these projects and which can look as difficult for the given proposal and current technology. The author is prepared to discuss the problems with serious organizations, which want to research and develop these projects.

  4. COOLING TOWER PUMP HOUSE, TRA606. CONNECTION TO COOLING TOWER. PUMPHOUSE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    COOLING TOWER PUMP HOUSE, TRA-606. CONNECTION TO COOLING TOWER. PUMP-HOUSE FLOOR PLAN AND FOUNDATION PLANS. LAYOUT OF SIX COOLING TOWER UNITS. BLAW-KNOX 3150-807-2, 12/1950. INL INDEX NO. 53-0607-62-098-100671, REV. 1. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  5. Cooling Towers, Energy Conservation Strategies 

    E-print Network

    Burger, R.

    1983-01-01

    COOLING TOWERS, ENERGY CONSERVATION STRATEGIES Robert Burger, Burger Associates, Inc., Dallas, Texas EVERY REFRIGERATION INSTALLATION, PETROCHEMICAL FACILITY AND CHEMICAL PLANT HAS A RESOURCE QUIETLY AWAITING EXPLOITATION - COLD WATER...,024 93,402 103,780 150 140.57 36,942 49,256 61,570 73.884 86,198 98,511 110,825 123,139 200 188.65 49.577 66,103 82,629 99.154 115,680 132,206 148,732 165,257 BURGER ASSOCIATES INC. FIGURE 5: RELATIONSHIP BETWEEN HORSE POWER AND ENERGY COSTS...

  6. 78 FR 17183 - Information Collection: Grey Towers Visitor Comment Card

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-20

    ...Forest Service Information Collection: Grey Towers Visitor Comment Card AGENCY: Forest...information collection 0596- 0222, ``Grey Towers Visitor Comment Card'' with 0596-0226...Nicole Bernarsky, USDA Forest Service, Grey Towers National Historic Site,...

  7. APPROACH BRIDGE PORTION OF VALVE TOWER FOOT BRIDGE, AS SEEN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    APPROACH BRIDGE PORTION OF VALVE TOWER FOOT BRIDGE, AS SEEN FROM BELOW, SHOWING VALVE TOWER TO RIGHT. VIEW FACING NORTH - Schofield Barracks Military Reservation, Ku Tree Reservoir, Valve Tower Foot Bridge, Kalakoa Stream, East Range, Wahiawa, Honolulu County, HI

  8. DETAIL OF VALVE TOWER SHOWING SLUICE GATE ON EAST SIDE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL OF VALVE TOWER SHOWING SLUICE GATE ON EAST SIDE OF TOWER. VIEW FACING WEST - Schofield Barracks Military Reservation, Ku Tree Reservoir, Valve Tower, Kalakoa Stream, East Range, Wahiawa, Honolulu County, HI

  9. 98. SOUTH FRONT OF MODEL. FREESTANDING TOWER TOP AT RIGHT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    98. SOUTH FRONT OF MODEL. FREESTANDING TOWER TOP AT RIGHT REPRESENTED ALTERNATE PROPOSAL FOR NORTH TOWER TO MATCH FLAG TOWER - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  10. Session: What have studies of communications towers suggested regarding the impact of guy wires and lights on birds and bats

    SciTech Connect

    Kerlinger, Paul

    2004-09-01

    This session at the Wind Energy and Birds/Bats workshop consisted of one presentation followed by a discussion/question and answer period. The paper ''Wind turbines and Avian Risk: Lessons from Communications Towers'' was given by Paul Kerlinger. The presenter outlined lessons that have been learned from research on communications (not cell) towers and about the impacts of guy wires and lights on birds and bats and how they could be useful to wind energy developers. The paper also provided specific information about a large 'fatality' event that occurred at the Mountaineer, WC wind energy site in May 2003, and a table of Night Migrant Carcass search findings for various wind sites in the US.

  11. Wind energy.

    PubMed

    Leithead, W E

    2007-04-15

    From its rebirth in the early 1980s, the rate of development of wind energy has been dramatic. Today, other than hydropower, it is the most important of the renewable sources of power. The UK Government and the EU Commission have adopted targets for renewable energy generation of 10 and 12% of consumption, respectively. Much of this, by necessity, must be met by wind energy. The US Department of Energy has set a goal of 6% of electricity supply from wind energy by 2020. For this potential to be fully realized, several aspects, related to public acceptance, and technical issues, related to the expected increase in penetration on the electricity network and the current drive towards larger wind turbines, need to be resolved. Nevertheless, these challenges will be met and wind energy will, very likely, become increasingly important over the next two decades. An overview of the technology is presented. PMID:17272245

  12. Summary of wind data from nuclear power plant sites. [USA

    Microsoft Academic Search

    Verholek

    1977-01-01

    A summary of wind data from nuclear power plant sites is presented. National Weather Service archives are an immediately obvious source of wind data, but additional data sources are also available. Utility companies proposing to build nuclear power plants are required to establish on-site meteorological monitoring programs that include towers for collecting wind and temperature data for use in environmental

  13. Arnold Schwarzenegger California Wind Energy

    E-print Network

    upon the accuracy or adequacy of the information in this report. #12;i Acknowledgements The project the commissioning and decommissioning of the Transtower tower. Randy Wells and the staff of Maverick Media as well;iii Abstract This report presents the results of a project designed to improve the accuracy of wind

  14. Coupled Dynamic Analysis of Multiple Unit Floating Offshore Wind Turbine 

    E-print Network

    Bae, Yoon Hyeok

    2013-04-23

    In the present study, a numerical simulation tool has been developed for the rotor-floater-tether coupled dynamic analysis of Multiple Unit Floating Offshore Wind Turbine (MUFOWT) in the time domain including aero-blade-tower dynamics and control...

  15. Dry cooling tower with water augmentation

    Microsoft Academic Search

    R. G. Ireland; V. N. Tramontini

    1981-01-01

    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

  16. Drift eliminators and cooling tower performance

    SciTech Connect

    Becker, B.R. (Univ. of Missouri, Kansas City, MO (United States)); Burdick, L.F. (Marley Cooling Tower Co., Mission, KS (United States))

    1993-06-01

    This article examines the evaluation of wet, mechanical draft cooling tower performance. The topics of the article include evaluation of cooling tower components, a description of the facility used in the evaluations, methodology used, the results of the evaluation, the importance of drift droplet collection efficiency and fan system pressure loss in evaluating the performance of the drift eliminator packs.

  17. A comprehensive approach to cooling tower design

    Microsoft Academic Search

    Nenad Milosavljevic; Pertti Heikkilä

    2001-01-01

    In this paper, a mathematical model for a counterflow wet cooling tower is derived, which is based on one-dimensional heat and mass balance equations using the measured heat transfer coefficient. The balance equations are solved numerically to predict the temperature change of air and water, as well as the humidity as a function of the cooling tower high. Experimental measurements

  18. Modelling of cooling tower splash pack

    Microsoft Academic Search

    A. A. Dreyer; P. J. Erens

    1996-01-01

    A mathematical model and a computer simulation program have been developed for the modelling of counterflow cooling tower splash pack thermal performance. The one-dimensional model uses basic aerodynamic, hydrodynamic and heat\\/mass transfer information to predict the performance of the packing material without depending on cooling tower test data. The predicted transfer characteristics and pressure drop data obtained with the simulation

  19. COKE QUENCH TOWER EMISSION TESTING PROGRAM

    EPA Science Inventory

    The report gives results of a field study to further define quench tower organic emissions, the character and magnitude of which are virtually unknown. (Limited testing in 1976 indicated that a large quantity of organic material was emitted from quench towers, but these data were...

  20. New technology and cooling tower design practices

    Microsoft Academic Search

    Lefevre

    1977-01-01

    When a direct link to the water source, called once-through cooling, is ruled-out, the use of cooling towers to supply cool water to the condensers is a very common option. Cooling towers are an increasingly common choice simply because they are capable of meeting the needs best, in most cases. This, in turn, is a matter of flexibility and economy

  1. CELLULAR TOWER PROLIFERATION IN THE UNITED STATES

    Microsoft Academic Search

    THOMAS A. WIKLE

    ????????. Since the early ????s the growing popularity of cellular communication has wrought dramatic landscape changes on the American scene through an invasion of thou- sands of cellular telephone towers. Objections raised to new tower construction by local residents, interest groups, and regulatory boards range from visual impacts to perceived health risks. This essay traces the origins of wireless telephony,

  2. 3. West elevation of Signal Tower. Delaware, Lackawanna & ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. West elevation of Signal Tower. - Delaware, Lackawanna & Western Railroad, Scranton Yards, Mattes Street Signal Tower, 80 feet Southwest of Railroad Alley & Cedar Avenue, Scranton, Lackawanna County, PA

  3. 2. Signal Tower, looking east. Delaware, Lackawanna & Western ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Signal Tower, looking east. - Delaware, Lackawanna & Western Railroad, Scranton Yards, Mattes Street Signal Tower, 80 feet Southwest of Railroad Alley & Cedar Avenue, Scranton, Lackawanna County, PA

  4. VALVE TOWER FROM HIGH GROUND NEAR APPROACH BRIDGE. VIEW FACING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VALVE TOWER FROM HIGH GROUND NEAR APPROACH BRIDGE. VIEW FACING NORTHEAST - Schofield Barracks Military Reservation, Ku Tree Reservoir, Valve Tower, Kalakoa Stream, East Range, Wahiawa, Honolulu County, HI

  5. Wireless Event-Triggered Controller for a 3D Tower Crane Lab Process Faisal Altaf, Jose Araujo, Aitor Hernandez, Henrik Sandberg and Karl Henrik Johansson

    E-print Network

    Johansson, Karl Henrik

    Wireless Event-Triggered Controller for a 3D Tower Crane Lab Process Faisal Altaf, Jos´e Ara and real-time im- plementation of an event-triggered controller for a nonlin- ear 3D tower crane where-power wireless sensor networks (WSNs) for industrial automation and process con- trol. While WSNs have been

  6. Evaluation of Wind Profiler Data

    NASA Technical Reports Server (NTRS)

    Manobianco, John; Palmblad, Robert

    1999-01-01

    This report presents the Applied Meteorology Unit's evaluation of a "Hypersodar" wind profiler located on KSC adjacent to tower 412. The sodar data used for this evaluation were collected during two different periods in March 1999 and November 1998. The evaluation is performed by calculating sodar data availability as a function of height, and bias and Root Mean Square (RMS) differences of wind speed and direction between sodar and tower 313 observations at comparable heights. The RMS differences in wind speed and wind direction from sodar wind solution B at KSC range from 0.65 m s (exp. -1) - 2.04 m s (exp. -1) and 4.5 - 32.3 deg., respectively. Note that these RMS differences are not bias-corrected. The vendor claims that the accuracy of the wind measurements from the sodar is better than 0.5 m s (exp -1) in speed and 10 deg. in direction. The results of the evaluation described here suggest that such accuracy may be attainable though the data available for this comparison made it impossible to confirm the vendor's claims. The sodar was not aligned with true north and was separated by a distance of 3.5 km from tower 313 used for comparisons in this study.

  7. Carbon Nanotube Tower-Based Supercapacitor

    NASA Technical Reports Server (NTRS)

    Meyyappan, Meyya (Inventor)

    2012-01-01

    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.

  8. Sustainable Energy Solutions Task 1.0: Networked Monitoring and Control of Small Interconnected Wind Energy Systems

    SciTech Connect

    Janet.twomey@wichita.edu

    2010-04-30

    EXECUTIVE SUMARRY This report presents accomplishments, results, and future work for one task of five in the Wichita State University Sustainable Energy Solutions Project: To develop a scale model laboratory distribution system for research into questions that arise from networked control and monitoring of low-wind energy systems connected to the AC distribution system. The lab models developed under this task are located in the Electric Power Quality Lab in the Engineering Research Building on the Wichita State University campus. The lab system consists of four parts: 1. A doubly-fed induction generator 2. A wind turbine emulator 3. A solar photovoltaic emulator, with battery energy storage 4. Distribution transformers, lines, and other components, and wireless and wired communications and control These lab elements will be interconnected and will function together to form a complete testbed for distributed resource monitoring and control strategies and smart grid applications testing. Development of the lab system will continue beyond this project.

  9. Modifying Wind Speed Data Observed from Manual Observation System to Automatic Observation System Using Wavelet Neural Network

    NASA Astrophysics Data System (ADS)

    Wang, Ju-Jie; Zhang, Wen-Yu; Liu, Xin; Wang, Cheng-Yuan

    Recently, manual observations sequence has been gradually replaced by automatic observation sequence. The difference between manual observation sequence and automatic observation sequence is somewhat inevitable. This challenges the homogeneity and the continuity of historical weather data, and influences atmospheric researches and applications. Therefore, based on the understanding of the influence caused by the two observation sequences, how to modify the data of manual observation sequence to automatic observation sequence has become a problem. In this paper, a model, which modifies the wind speed data of manual observation suquence to automatic observation sequence, is established using the wavelet neural network (WNN). The proposed model achieves 13.38% in mean absolute percentage error (MAPE) compared to automatic observation data sequence. For wind speed, it could be a promising candidate for modifying manual observation data sequence to automatic observation data sequence.

  10. The Effect of Variable Speed Wind Turbines on the Operation of Weak Distribution Networks

    Microsoft Academic Search

    Fotis D. Kanellos; N. D. Hatziargyriou

    2002-01-01

    This paper analyses the repercussions from the connection of wind parks (WP) on the operation of weak electric distribution systems, based on simulation results. The effects on the voltage profile caused by variable-speed (VS) wind turbines (WT) are compared to the effects caused by fixed speed (FS) WTs. Both types of WT are assumed to be equipped with asynchronous machines.

  11. The effect of variable-speed wind turbines on the operation of weak distribution networks

    Microsoft Academic Search

    F. D. Kanellos; N. D. Hatziargyriou

    2002-01-01

    This paper analyzes the repercussions from the connection of wind parks (WPs) on the operation of weak electric distribution systems, based on simulation results. The effects on the voltage profile caused by variable-speed (VS) wind turbines (WTs) are compared to the effects caused by fixed-speed (FS) WTs. Both types of WTs are assumed to be equipped with asynchronous machines. In

  12. Review of New Concepts, Ideas and Innovations in Space Towers

    E-print Network

    Krinker, Mark

    2010-01-01

    Under Space Tower the author understands structures having height from 100 km to the geosynchronous orbit and supported by surface of Earths. The classical Space Elevator is not included in space towers. That has three main identifiers which distingue from Space Tower: Space Elevator has part over Geosynchronous Orbit (GSO) and all installation supported only the centrifugal force of Earth, immobile cable connected to surface of Earth, no pressure on the surface. A lot of new concepts, ideas and innovation in space towers were offered, developed and researched in last years especially after 2000. For example: optimal solid space towers, inflatable space towers (include optimal space tower), circle and centrifugal space towers, kinetic space towers, electrostatic space towers, electromagnetic space towers, and so on. Given review shortly summarizes there researches and gives a brief description them, note some their main advantages, shortcomings, defects and limitations.

  13. Review of New Concepts, Ideas and Innovations in Space Towers

    E-print Network

    Mark Krinker

    2010-02-11

    Under Space Tower the author understands structures having height from 100 km to the geosynchronous orbit and supported by surface of Earths. The classical Space Elevator is not included in space towers. That has three main identifiers which distingue from Space Tower: Space Elevator has part over Geosynchronous Orbit (GSO) and all installation supported only the centrifugal force of Earth, immobile cable connected to surface of Earth, no pressure on the surface. A lot of new concepts, ideas and innovation in space towers were offered, developed and researched in last years especially after 2000. For example: optimal solid space towers, inflatable space towers (include optimal space tower), circle and centrifugal space towers, kinetic space towers, electrostatic space towers, electromagnetic space towers, and so on. Given review shortly summarizes there researches and gives a brief description them, note some their main advantages, shortcomings, defects and limitations.

  14. Wind turbine/generator set and method of making same

    DOEpatents

    Bevington, Christopher M.; Bywaters, Garrett L.; Coleman, Clint C.; Costin, Daniel P.; Danforth, William L.; Lynch, Jonathan A.; Rolland, Robert H.

    2013-06-04

    A wind turbine comprising an electrical generator that includes a rotor assembly. A wind rotor that includes a wind rotor hub is directly coupled to the rotor assembly via a simplified connection. The wind rotor and generator rotor assembly are rotatably mounted on a central spindle via a bearing assembly. The wind rotor hub includes an opening having a diameter larger than the outside diameter of the central spindle adjacent the bearing assembly so as to allow access to the bearing assembly from a cavity inside the wind rotor hub. The spindle is attached to a turret supported by a tower. Each of the spindle, turret and tower has an interior cavity that permits personnel to traverse therethrough to the cavity of the wind rotor hub. The wind turbine further includes a frictional braking system for slowing, stopping or keeping stopped the rotation of the wind rotor and rotor assembly.

  15. Augmented Reality Tower Technology Assessment

    NASA Technical Reports Server (NTRS)

    Reisman, Ronald J.; Brown, David M.

    2009-01-01

    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.

  16. Coupling a Neural Network-Based forward Model and a Bayesian Inversion Approach to Retrieve Wind Field from Spaceborne Polarimetric Radiometers

    PubMed Central

    Pulvirenti, Luca; Pierdicca, Nazzareno; Marzano, Frank S.

    2008-01-01

    A simulation study to assess the potentiality of sea surface wind vector estimation based on the approximation of the forward model through Neural Networks and on the Bayesian theory of parameter estimation is presented. A polarimetric microwave radiometer has been considered and its observations have been simulated by means of the two scale model. To perform the simulations, the atmospheric and surface parameters have been derived from ECMWF analysis fields. To retrieve wind speed, Minimum Variance (MV) and Maximum Posterior Probability (MAP) criteria have been used while, for wind direction, a Maximum Likelihood (ML) criterion has been exploited. To minimize the cost function of MAP and ML, conventional Gradient Descent method, as well as Simulated Annealing optimization technique, have been employed. Results have shown that the standard deviation of the wind speed retrieval error is approximately 1.1 m/s for the best estimator. As for the wind direction, the standard deviation of the estimation error is less than 13° for wind speeds larger than 6 m/s. For lower wind velocities, the wind direction signal is too weak to ensure reliable retrievals. A method to deal with the non-uniqueness of the wind direction solution has been also developed. A test on a case study has yielded encouraging results.

  17. Wind Monitoring Report for Fort Wainwright's Donnelly Training Area

    SciTech Connect

    Orrell, Alice C.; Dixon, Douglas R.

    2011-01-18

    Using the wind data collected at a location in Fort Wainwright’s Donnelly Training Area (DTA) near the Cold Regions Test Center (CRTC) test track, Pacific Northwest National Laboratory (PNNL) estimated the gross and net energy productions that proposed turbine models would have produced exposed to the wind resource measured at the meteorological tower (met tower) location during the year of measurement. Calculations are based on the proposed turbine models’ standard atmospheric conditions power curves, the annual average wind speeds, wind shear estimates, and standard industry assumptions.

  18. Wind Climate Analyses for SRTC's Central Climatology Site

    SciTech Connect

    Weber, A.H.

    2003-06-23

    This report was written to present climatological summaries of the wind data at the Central Climatology (CC) tower in a convenient format and to point out some features of the wind speed and direction that have not been widely appreciated in the past. Short-term (two-week) wind roses provide a means to demonstrate the temporal and spatial relationships that wind speed and direction undergo using a ten-year database from the CC tower. These relationships are best demonstrated by examining the figures provided in this report or looking at loops of computer-generated images provided by the authors.

  19. Geology of Devils Tower National Monument, Wyoming

    USGS Publications Warehouse

    Robinson, Charles Sherwood

    1956-01-01

    Devils Tower is a steep-sided mass of igneous rock that rises above the surrounding hills and the valley of the Belle Fourche River in Crook County, Wyo. It is composed of a crystalline rock, classified as phonolite porphyry, that when fresh is gray but which weathers to green or brown. Vertical joints divide the rock mass into polygonal columns that extend from just above the base to the top of the Tower. The hills in the vicinity and at the base of the Tower are composed of red, yellow, green, or gray sedimentary rocks that consist of sandstone, shale, or gypsum. These rocks, in aggregate about 400 feet thick, include, from oldest to youngest, the upper part of the Spearfish formation, of Triassic age, the Gypsum Spring formation, of Middle Jurassic age, and the Sundance formation, of Late Jurassic age. The Sundance formation consists of the Stockade Beaver shale member, the Hulett sandstone member, the Lak member, and the Redwater shale member. The formations have been only slightly deformed by faulting and folding. Within 2,000 to 3.000 feet of the Tower, the strata for the most part dip at 3 deg - 5 deg towards the Tower. Beyond this distance, they dip at 2 deg - 5 deg from the Tower. The Tower is believed to have been formed by the intrusion of magma into the sedimentary rocks, and the shape of the igneous mass formed by the cooled magma is believed to have been essentially the same as the Tower today. Devils Tower owes its impressiveness to its resistance to erosion as compared with the surrounding sedimentary rocks, and to the contrast of the somber color of the igneous column to the brightly colored bands of sedimentary rocks.

  20. A model for yawing dynamic optimization of a wind turbine structure

    Microsoft Academic Search

    Karam Y. Maalawi

    2007-01-01

    A novel design optimization model for placing frequencies of a wind turbine tower\\/nacelle\\/rotor structure in free yawing motion is developed and discussed. The main aim is to avoid large amplitudes caused by the yawing-induced vibrations in the case of horizontal-axis wind turbines or rotational motion of the blades about the tower axis in case of vertical-axis wind turbines. This can

  1. 17. VIEW OF THE TOP OF THE TOWER SHOWING BASE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    17. VIEW OF THE TOP OF THE TOWER SHOWING BASE OF TOWER MAST AND WOOD DECKING ON SIGNAL TOWER ROOF. - U.S. Naval Base, Pearl Harbor, Signal Tower, Corner of Seventh Street & Avenue D east of Drydock No. 1, Pearl City, Honolulu County, HI

  2. Optimal sequencing of a cooling tower with multiple cells

    E-print Network

    Zhang, Z.; Liu, J.

    2012-01-01

    This paper evaluates the energy savings potential of multi-cell cooling tower optimal sequencing control methods. Annual tower fan energy usage is calculated for a counter-flow tower with multiple variable-speed fans. Effectiveness-NTU tower model...

  3. Study on dynamic optimum design of tower crane structure

    Microsoft Academic Search

    Weihua Yang; Yourong Li; Zifan Fang; Kongde He

    2011-01-01

    The tower crane is a kind of construction machine which are widely used in the engineering construction, especially in modernized industry and civil construction. As the main skeleton of the tower crane, the design of the metal structure is very important for the operational reliability and the security of tower crane. The former design methods for tower crane structural were

  4. Stabilization of gird connected wind generator during power network disturbances by STATCOM

    Microsoft Academic Search

    M. Jazayeri; M. Fendereski

    2007-01-01

    The response of wind energy installations to gird disturbances is studied in this panel session contribution. For the variable-speed turbine installations, the influence of using various levels of reactive power in-feed from the wind energy installation is investigated. Recently voltage-source or current-source inverter based various FACTS devices have been used for flexible power flow control, secure loading and damping of

  5. Wind for Schools Project Power System Brief

    SciTech Connect

    Not Available

    2007-08-01

    This fact sheet provides an overview of the system components of a Wind Powering America Wind for Schools project. Wind Powering America's (WPA's) Wind for Schools project uses a basic system configuration for each school project. The system incorporates a single SkyStream(TM) wind turbine, a 70-ft guyed tower, disconnect boxes at the base of the turbine and at the school, and an interconnection to the school's electrical system. A detailed description of each system component is provided in this document.

  6. Cooling Towers, The Neglected Energy Resource 

    E-print Network

    Burger, R.

    1985-01-01

    Loving care is paid to the compressors, condensers, and computer programs of refrigeration systems. When problems arise, operator: run around in circles with expensive "fixes", but historically ignore the poor orphan, the cooling tower perched...

  7. Cooling Towers--Energy Conservation Strategies

    E-print Network

    Matson, J.

    A cooling water system can be optimized by operating the cooling tower at the highest possible cycles of concentration without risking sealing and fouling of heat exchanger surfaces, tube bundles, refrigeration equipment, overhead condensers...

  8. Ozone inhibits corrosion in cooling towers

    NASA Technical Reports Server (NTRS)

    French, K. R.; Howe, R. D.; Humphrey, M. F.

    1980-01-01

    Commercially available corona discharge ozone generator, fitted onto industrial cooling tower, significantly reduces formation of scales (calcium carbonate) and corrosion. System also controls growth of algae and other microorganisms. Modification lowers cost and improves life of cooling system.

  9. Cooling Tower Considerations for Energy Optimizations

    E-print Network

    Burger, R.

    1986-01-01

    Energy conservation strategies and production economies involve more than examining the cooling tower fan consumption of horse power. Colder water provides vast potentials for savings. Ask yourself, "What is the dollar and energy utilization value...

  10. On thermal performance of seawater cooling towers

    E-print Network

    Sharqawy, Mostafa H.

    Seawater cooling towers have been used since the 1970s in power generation and other industries, so as to reduce the consumption of freshwater. The salts in seawater are known to create a number of operational problems, ...

  11. Alternative water treatment for cooling towers

    SciTech Connect

    Wilsey, C.A. [Water Clear, Inc., Mound, MN (United States)

    1997-04-01

    Problems commonly found in cooling towers include: calcium scale formation, corrosion, algae and bacterial growth. These problems can inhibit a cooling tower from operating at its most efficient capacity. An energy-saving, cost-efficient method to control each of these problems in tower water will ultimately benefit the owner as well as the environment. Supplemental ionic water purification was developed to overcome the disadvantages associates with a total chemical disinfection system. The concept of supplemental ionic water purification was developed in the early 1900s and later reviewed by NASA in the mid-1960`s. Only in the past seven years have biologists combined copper ions with chlorine to act as a bactericide. The findings have shown that metal compound ions (copper), when absorbed by bacteria, affect the organisms enzyme balance. This combination inhibits the organism`s reproduction and respiration capabilities. This technology has been applied to cooling tower operations as an alternative to a chemical-only regimen.

  12. Projective preservation : reframing Rudolph's Tower for Boston

    E-print Network

    Turner, Jessica K

    2012-01-01

    By 2012, the fate of Paul Rudolph's tower in downtown Boston has been in question for years while a vision of a denser city calls for its demolition. Projected development on the site currently argues that to move forward, ...

  13. Wind driven air pump

    SciTech Connect

    Beisel, V.A.

    1983-05-31

    An improved pump for lifting water from an underground source utilizes a wind motor for driving an oil-less air compressor eliminating oil contamination of ground water which is forced to the surface. The wind motor is movable to face the wind by means of a novel swivel assembly which also eliminates the formation and freezing of condensate within the airline from the compressor. The propeller blades of the wind motor and the tail section are formed from a pair of opposed convex air foil shaped surfaces which provide the propeller blades and the tail section with fast sensitivity to slight changes in wind direction and speed. A novel well tower for supporting the wind motor and compressor and for lifting the water from the underground source is an optional modification which requires no welding and eliminates the problem of condensate freezing in the airline going to the well. The wind driven air pump disclosed is lightweight, can be easily installed, is relatively inexpensive to produce and is virtually maintenance-free and capable of operating in winds exceeding 100 miles per hour.

  14. Soaring Towers: Building with Recycled Materials

    NSDL National Science Digital Library

    TERC

    2010-01-01

    In this activity, learners will build the highest tower they can out of recycled materials. As they work on this activity, they explore which shapes and sizes make good tower bases, which work well in the middle, and how to make sure the configuration is stable, even when some of the shapes are quite irregular. Available as a web page, downloadable pdf, and in Spanish.

  15. Modeling, simulation and control of crude towers

    SciTech Connect

    Hsie, W.L.

    1989-01-01

    A crude tower which separates crude oil into various petroleum fractions, is one of the most complex units in the refining industry. A mathematical model for the rigorous dynamic simulation of a crude tower is developed. The non-linear, coupled modeling equations of a crude tower form a very large set of stiff ordinary differential and algebraic equations. The large dimension and stiffness make the simulation very time consuming. A new model, which is based on a separated component concept, is shown to be able to reduce the dimension and stiffness of the system, and save a large amount of computer time. Several authors who tried to apply the bubble point algorithm (BPA) to solve the modeling equations of crude towers reported difficulties with convergence. In this research, it is shown that the bubble point temperature is extremely sensitive to the error in liquid composition of the components with a wide range of volatility. This sensitivity causes numerical instability of the BPA. The sum of rates algorithm (SRA) is shown to be more suitable for computing the steady state conditions of a crude tower by solving the modeling equations. Once an initial steady-state is reached, the transient responses of the crude tower can be obtained by BPA. The main objective of crude tower control is to maximize the production of more valuable products from the crude feed. This maximization can be accomplished by an effective product quality and pump around control scheme. A computer control algorithm, Quadratic Dynamic Matrix Control (QDMC), is applied to the control of a crude tower. Due to the multivariable and predictive nature of the QDMC algorithm, it handles the interactions of the product quality very effectively.

  16. Cooling Towers, The Neglected Energy Resource 

    E-print Network

    Burger, R.

    1987-01-01

    COOLING TOWERS, THE NEGLECTED ENERGY RESOURCE ROBERT BURGER President, Burger Associates, Inc. Dallas, Texas (USA) Loving care is paid to the compress ors, condensers, and computer programs of refrigeration and air conditioning systems... Handbook Chapter 21, 2. Energy Conservation page 11, (1975). 3. Colder Water 5. Robert Burger, "Cooling Tower Technology" Chapter 8, "Thermal Engineel'ing", (1979). 4. Greater GPM Cooling 6. A Texas college, test report and loca 5. Money Making...

  17. Wind Spires as an Alternative Energy Source

    SciTech Connect

    Majid Rashidi, Ph.D., P.E.

    2012-10-30

    This report discloses the design and development of an innovative wind tower system having an axisymmetric wind deflecting structure with a plurality of symmetrically mounted rooftop size wind turbines near the axisymmetric structure. The purpose of the wind deflecting structure is to increase the ambient wind speed that in turn results in an overall increase in the power capacity of the wind turbines. Two working prototypes were constructed and installed in the summer of 2009 and 2012 respectively. The system installed in the Summer of 2009 has a cylindrical wind deflecting structure, while the tower installed in 2012 has a spiral-shape wind deflecting structure. Each tower has 4 turbines, each rated at 1.65 KW Name-Plate-Rating. Before fabricating the full-size prototypes, computational fluid dynamic (CFD) analyses and scaled-down table-top models were used to predict the performance of the full-scale models. The performance results obtained from the full-size prototypes validated the results obtained from the computational models and those of the scaled-down models. The second prototype (spiral configuration) showed at a wind speed of 11 miles per hour (4.9 m/s) the power output of the system could reach 1,288 watt, when a typical turbine installation, with no wind deflecting structure, could produce only 200 watt by the same turbines at the same wind speed. At a wind speed of 18 miles per hour (8 m/sec), the spiral prototype produces 6,143 watt, while the power generated by the same turbines would be 1,412 watt in the absence of a wind deflecting structure under the same wind speed. Four US patents were allowed, and are in print, as the results of this project (US 7,540,706, US 7,679,209, US 7,845,904, and US 8,002,516).

  18. Science and Technical Considerations for Wind Farm Siting

    NSDL National Science Digital Library

    This instructional module was created at the 2009 ATEEC Fellows Institute on Wind Power. The following sections are provided: An introduction to wind power classes, Offshore turbine tower foundations, Wind speed lab, Wind shear project, Turbulence and links to supporting resources. The classroom lessons include student worksheets. The entire guide may be downloaded in PDF file format. This resource is free to download. Users must first create a login with ATEEC's website to access the file.

  19. Wind, Thermal, and Earthquake Monitoring of the Watts Towers

    E-print Network

    English, Jackson

    2013-01-01

    10°C. The difference between the east and west columns is10°C. The difference between the east and west columns wasdifference in the two columns’ behavior is noticed when looking at the north-south and east-west

  20. Networking CD-ROM.

    ERIC Educational Resources Information Center

    Jordahl, Gregory

    1993-01-01

    Discusses the use of CD-ROM networks in schools. Topics addressed include problems with networking CD-ROM, including accessing the operating system, speed, and the use of multimedia; peer-to-peer networking; client/server networking; drives, jukeboxes, and towers; and full-motion video networks. A sidebar lists CD-ROM servers. (LRW)

  1. Field measurements of boundary layer wind characteristics and wind-induced responses of super-tall buildings

    Microsoft Academic Search

    J. Y. Fu; Q. S. Li; J. R Wu; Y. Q. Xiao; L. L. Song

    2008-01-01

    This paper presents field measurement results of boundary layer wind characteristics over typical open country and urban terrains and wind-induced responses of two super-tall buildings during the passages of windstorms. The field data such as wind speed, wind direction and acceleration responses, etc., were measured from an observation tower with height of 17.5m at a coastal region in Lufeng and

  2. COOLING TOWER PUMP HOUSE, TRA606. SECTION, LAYOUT OF TOWERS. BLAWKNOX ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    COOLING TOWER PUMP HOUSE, TRA-606. SECTION, LAYOUT OF TOWERS. BLAW-KNOX 3150-7-2, 9/1950. INL INDEX NO. 531-0607-00-098-100014, REV. 2. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  3. Characteristics of Winter Lightning that Occurred on a Windmill and its Lightning Protection Tower

    NASA Astrophysics Data System (ADS)

    Takagi, Nobuyuki; Wang, Daohong

    We have obtained the electric current, electric field change, and optical image data or several tens of lightning that hit on a wind turbine and its lightning-protection tower during the past6 non-stop winter seasons from 2005 to 2010. By analyzing the data, we found that the upward lightning hitting on the high structures can be classified into self-initiated and other-triggered types according to whether there is a discharge activity prior to the upward lightning. We also found that although other-triggered upward lightning can start at a relatively lower wind speed, self-initiated upward lightning always started either from the stationary tower under a larger wind speed or from a rotating wind turbine blade. It appears that the wind and by inference the corona discharge shielding do have considerable effect in the initiation of an upward leader. Regarding the initial progression of a positive leader, we found a systematic difference in the speeds of the leaders from the structures that have remarkably different heights. Finally, we discussed the pulse discharges observed in the very initial stages of positive upward leaders and also how to forecast direct strike of upward lightning.

  4. Characteristics of Winter Lightning that Occurred on a Windmill and its Lightning Protection Tower in Japan

    NASA Astrophysics Data System (ADS)

    Wang, Daohong; Takagi, Nobuyuki

    We have observed lightning that struck a wind turbine and its neighboring lightning-protection tower during the past six winter seasons (2005 to 2010) using various lightning observation instruments. Our results show that the upward lightning from high structures can be classified into self-initiated and other-triggered types according to whether there is a discharge activity prior to the upward lightning. Furthermore, we found that although other-triggered upward lightning can start at a relatively low wind speed, self-initiated upward lightning always started either from the stationary tower under a larger wind speeds or from a rotating wind turbine blade. It appears that the wind does have considerable effect in assisting the initiation of an upward leader. In addition, we found that the self-initiated upward positive leaders from structures with different effective heights exhibited remarkably different initial speeds. Higher structures tend to initiate faster upward leaders. Finally, we discussed the pulse discharges observed in the very initial stages of positive upward leaders and how to protect structures from upward lightning as well.

  5. ICT in distribution networks with wind power generation to improve voltage profiles

    Microsoft Academic Search

    V. Calderaro; V. Galdi; S. Raiti; A. Vaccaro

    2004-01-01

    Dispersed generation (DG) is today considered one of the most important openings for electric power systems in a liberalized energy market, able to join the increasing power demands and more and more pressing social and environmental constraints. In most cases, renewable power generation, such as wind power, solar power, or low head hydropower production, guarantees a low environmental impact and

  6. Toward model free atmospheric sensing by aerial robot networks in strong wind fields

    Microsoft Academic Search

    Jack Elston; Maciej Stachura; Eric W. Frew; Ute C. Herzfeld

    2009-01-01

    This paper presents a system for in situ atmospheric sensing using an aerial robot system in the presence of a strong wind field. The geostatistical concept of the variogram is used to characterize regions of the environment with high variability, which is assumed to correlate with scientific interest. After regions of interest are identified, ordered upwind methods are used to

  7. Forecasting of wind speed using wavelets analysis and cascade-correlation neural networks

    E-print Network

    Paris-Sud XI, Université de

    energy consumption), managing energy demand, promoting renewable energy and energy savings are worldwide annual market in Europe after Spain and Germany. The healthy growth of wind energy in France can various reliable and robust tools with the aim of managing energy sources and promoting renewable energy

  8. Reconciling Latent and Sensible Energy Fluxes with Footprints in a Heterogeneous Landscape at an Urban-suburban Tower near Baltimore, Maryland

    NASA Astrophysics Data System (ADS)

    Saliendra, N. Z.; Hom, J. L.; Pouyat, R. V.; Nowak, D.; Heisler, G. M.; Petterson, M.; Yesilonis, I.; Crawford, B.; Grimmond, S.

    2009-12-01

    Measurements of eddy-fluxes in an urban-suburban landscape may create technical difficulties as latent and sensible energy fluxes in the tower’s footprint are non-uniform. In an earlier study, we have found that the average vegetation cover surrounding the Cub Hill tower was 64 %; ranging from 46 to 77 % among 8 wind directions. We measured latent and sensible energy fluxes using a closed-path eddy-covariance system in the Cub Hill tower near Baltimore, Maryland. Half-hourly values of latent and sensible energy fluxes were stratified according to 24 15-degree bins of wind direction in each of the 16-day compositing periods for Normalized Difference Vegetation Index (NDVI) during 3 years of study (2004 to 2006). We used the daytime latent and sensible energy fluxes in the multivariate regression analyses to model fluxes of water vapor or evapotranspiration (ET) and sensible heat (H) as functions of micrometeorological variables (net radiation, temperature, relative humidity, wind speed, and soil moisture), NDVI, and land cover. Empirical models are developed at 16-day intervals for each of the 24 bins of wind direction to establish the relationships between energy fluxes (i.e., latent and sensible) and footprints (i.e., micrometeorology, NDVI, and land cover) around the Cub Hill tower.

  9. Wind Turbine Safety and Function Test Report for the Gaia-Wind 11-kW Wind Turbine

    SciTech Connect

    Huskey, A.; Bowen, A.; Jager, D.

    2010-01-01

    This test was conducted as part of the U.S. Department of Energy's (DOE) Independent Testing project. This project was established to help reduce the barriers to wind energy expansion by providing independent testing results for small wind turbines (SWT). In total, four turbines were tested at the National Wind Technology Center (NWTC) as a part of this project. Safety and function testing is one of up to five tests performed on the turbines, including power performance, duration, noise, and power-quality tests. The results of the testing provide the manufacturers with reports that can be used for small wind turbine certification. The test equipment includes a Gaia-Wind 11-kW wind turbine mounted on an 18-m monopole tower. Gaia-Wind Ltd. manufactured the turbine in Denmark. The system was installed by the NWTC site operations group with guidance and assistance from Gaia-Wind.

  10. Short Term Climatological Wind Data as a Tool for Wind Forecasting

    SciTech Connect

    Parker, MJ

    2004-01-28

    Utilizing short-term climatological wind data can enhance wind speed and wind direction forecasts. An analysis of regional or tower-based wind rose summaries can be useful forecast guides especially when synoptic-scale pressure gradients are weak. Predictive data from multiple models can be plotted against short-term climatological wind data to assess deviations from expected norms and differences between forecast models. Site-specific comparisons between predicted data and observed climatological distributions can provide further insights to the forecaster. These methods can be applied to any location where sufficient climatological data (at least two years) is available.

  11. Wind vanes in the antiquity

    NASA Astrophysics Data System (ADS)

    Lindgrén, S.; Neumann, J.

    1983-06-01

    Mesopotamia: An Akkadian tablet, the original of which was incised between about 1800 and 1600 B.C., makes explicit mention of a wind vane. Further three Sumero-Akkadian “dictionaries” have three different names for the single Akkadian name for wind vane. Since the latest period of flourishing of the Sumerian civilization took place between about 2 100 and 2000 B.C., wind vanes must have been in use in ancient Mesopotamia already about 4000 years ago, i.e. about 2000 years before the Chinese and Greeks had wind vanes. The Mesopotamian wind vanes were made of wood. China: It appears from the old Chinese literature that streamers were in use about the 2nd century B.C. in China for wind vanes. Shortly thereafter, a wind vane in the shape of a bird made of bronze is mentioned in the literature. Greece: The wind vane in the shape of a triton that was fixed, according to Vitruvius, to the top of the Tower of Winds at Athens, must have disappeared before A.D. 1436. Roman Empire: According to a passage in Dio Chrysostom's writtings, streamers appear to have been used for wind vanes. What seems to be the first wind vane in the shape of a cock, was erected in the 2nd century A.D. on the top of the mausoleum of the Flavians, in a North African province of the Roman Empire.

  12. Model validation: Cooling-tower performance

    SciTech Connect

    Miller, P.B.; Starnes, G.L. (Pacific Gas and Electric Co., San Ramon, CA (USA). Technical and Ecological Services)

    1989-11-01

    The purpose of the fill performance validation project is to examine the accuracy of the cooling tower computer models and fill performance data that have recently been made available through EPRI. This project compares actual full scale tower performance test results to those predicted by the tower models. The cooling tower models used in this project include: FACTS/FACTR, developed by the Tennessee Valley Authority (TVA); VERA2D-86/VERAT, developed by CHAM of North America; and TEFERI, developed by Electricite de France. All full scale cooling tower performance test data used to validate the models were collected at PG E's Full Scale Crossflow Testing Facility. Three different fills have been tested in this facility during this project. Test results for one of the fill types (Type T') are directly compared to predictions based on results from the EPRI Small Scale Test Facility. The other full scale test results are used to validate the hybrid fill modeling capabilities of the FACTS computer code. 9 refs., 6 figs., 7 tabs.

  13. *Corresponding author. E-mail: kareem@navier.ce.nd.edu. Journal of Wind Engineering

    E-print Network

    Kareem, Ahsan

    *Corresponding author. E-mail: kareem@navier.ce.nd.edu. Journal of Wind Engineering and Industrial Aerodynamics 77&78 (1998) 725--739 Aerodynamics of Nanjing Tower: A case study Ahsan Kareem *, Scott Kabat Numerical simulations and experimental measurements of the aerodynamics of the Nanjing Tower have been

  14. Establishing a Comprehensive Wind Energy Program

    SciTech Connect

    Fleeter, Sanford [Purdue University

    2012-09-30

    This project was directed at establishing a comprehensive wind energy program in Indiana, including both educational and research components. A graduate/undergraduate course ME-514 - Fundamentals of Wind Energy has been established and offered and an interactive prediction of VAWT performance developed. Vertical axis wind turbines for education and research have been acquired, instrumented and installed on the roof top of a building on the Calumet campus and at West Lafayette (Kepner Lab). Computational Fluid Dynamics (CFD) calculations have been performed to simulate these urban wind environments. Also, modal dynamic testing of the West Lafayette VAWT has been performed and a novel horizontal axis design initiated. The 50-meter meteorological tower data obtained at the Purdue Beck Agricultural Research Center have been analyzed and the Purdue Reconfigurable Micro Wind Farm established and simulations directed at the investigation of wind farm configurations initiated. The virtual wind turbine and wind turbine farm simulation in the Visualization Lab has been initiated.

  15. The 100 kW experimental wind turbine generator project

    NASA Technical Reports Server (NTRS)

    Puthoff, R. L.; Sirocky, P.

    1975-01-01

    The Energy Research and Development Administration and the NASA Lewis Research Center engaged jointly in a Wind Energy Program which included the design and erection of a 100 kW wind turbine generator. This test machine consists of a rotor turbine, transmission, shaft, alternator, and tower. The rotor, measuring 125 feet in diameter and consisting of two variable pitch blades, operates at 40 rpm and generates 100 kW of electrical power at a wind velocity of 18 mph. The entire assembly is placed on top of a tower 100 feet above ground level. The machine was scheduled to be ready for operation in August, 1975.

  16. Long-Term Considerations on Wind Power's Environmental Impact

    E-print Network

    operational phases · Major contributions - Impacts from tower and foundation (e.g. steel production-Cycle Assessment - Present - Products - Lifecycle perspective, processes of different phases - Comprehensive Turbines and Wind Farms · Main impacts from the production of the materials for the wind turbines; not from

  17. High Tip Speed Operation for Offshore Wind Turbines

    Microsoft Academic Search

    Andreas Knauer; Tor David Hanson

    Summary The operation of large offshore wind turbines at high rotational speeds is investigated with focus on rotor aerodynamics, performance for the extended operational range and the potential for tower top mass reductions. 2D aerodynamic investigations were carried out with the program XFOIL on the NACA 63415 airfoil. Several 5 MW wind turbine rotors were designed to operate at tip

  18. The Argonne Boundary Layer Experiments Facility: Using Minisodars to Complement a Wind Profiler Network

    Microsoft Academic Search

    R. L. Coulter; G. Klazura; B. M. Lesht; T. J. Martin; J. D. Shannon; D. L. Sisterson; M. L. Wesely

    1999-01-01

    Summary   A description of the Argonne Boundary Layer Experiments (ABLE) facility, located in southern Kansas, USA, to study the planetary\\u000a boundary layer on a continuous basis is given. The use and role of the minisodars in these studies is shown to be important\\u000a and necessary in the study of surface boundary layers, extension of wind profiles to the surface, and

  19. Examination of objective analysis precision using wind profiler and radiosonde network data

    SciTech Connect

    Mace, G.G.; Ackerman, T.P. [Penn State Univ., University Park, PA (United States)

    1996-04-01

    One of the principal research strategies that has emerged from the science team of the Atmospheric Radiation Measurement (ARM) Program is the use of a single column model (SCM). The basic assumption behind the SCM approach is that a cloud and radiation parameterization embedded in a general circulation model can be effectively tested and improved by extracting that column parameterization from the general circulation model and then driving this single column at the lateral boundaries of the column with diagnosed large-scale atmospheric forcing. A second and related assumption is that the large-scale atmospheric state, and hence the associated forcing, can be characterized directly from observations. One of the primary reasons that the Southern Great Plains (SGP) site is located in Lamont, Oklahoma, is because Lamont is at the approximate center of the NOM Wind Profiler Demonstration Array (WPDA). The assumption was that hourly average wind profiles provided by the 7 wind profilers (one Lamont and six surrounding it in a hexagon) coupled with radiosonde launches every three hours at 5 sites (Lamont plus four of the six profiler locations forming the hexagon) would be sufficient to characterize accurately the large-scale forcing at the site and thereby provide the required forcing for the SCM. The goal of this study was to examine these three assumptions.

  20. Wind resource characterization results to support the Sandia Wind Farm Feasibility Study : August 2008 through March 2009.

    SciTech Connect

    Deola, Regina Anne

    2010-01-01

    Sandia National Laboratories Wind Technology Department is investigating the feasibility of using local wind resources to meet the requirements of Executive Order 13423 and DOE Order 430.2B. These Orders, along with the DOE TEAM initiative, identify the use of on-site renewable energy projects to meet specified renewable energy goals over the next 3 to 5 years. A temporary 30-meter meteorological tower was used to perform interim monitoring while the National Environmental Policy Act (NEPA) process for the larger Wind Feasibility Project ensued. This report presents the analysis of the data collected from the 30-meter meteorological tower.

  1. Cooling tower water conditioning study. [using ozone

    NASA Technical Reports Server (NTRS)

    Humphrey, M. F.; French, K. R.

    1979-01-01

    Successful elimination of cooling tower treatment chemicals was demonstrated. Three towers functioned for long periods of time with ozone as the only treatment for the water. The water in the systems was reused as much as 30 times (cycles of concentration) without deleterious effects to the heat exchangers. Actual system blow-down was eliminated and the only makeup water added was that required to replace the evaporation and mist entrainment losses. Minimum water savings alone are approximately 75.1 1/kg/year. Cost estimates indicate that a savings of 55 percent was obtained on the systems using ozone. A major problem experienced in the use of ozone for cooling tower applications was the difficulty of accurate concentration measurements. The ability to control the operational characteristics relies on easily and accurately determined concentration levels. Present methods of detection are subject to inaccuracies because of interfering materials and the rapid destruction of the ozone.

  2. Engineering photochemical smog through convection towers

    SciTech Connect

    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.

    1995-02-01

    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.

  3. ValidWind applications: wind power prospecting, aerosol transport

    NASA Astrophysics Data System (ADS)

    Wilkerson, T.; Marchant, A.; Apedaile, T.; Scholes, D.; Simmons, J.; Bradford, B.

    2010-10-01

    The ValidWind™ system employs an XL200 laser rangefinder to track small, lightweight, helium-filled balloons (0.33 meters, 0.015 kg). We record their trajectories (range resolution 0.5 meters) and automatically produce local wind profiles in real time. Tracking range is enhanced beyond 2 km by applying retro-reflector tape to the balloons. Aerodynamic analysis shows that ValidWind balloon motion is well coupled to the local wind within relaxation times { 1 second, due to drag forces at subcritical Reynolds numbers Re < 2×105. Such balloons are Lagrangian sensors; i.e., they move with the wind as opposed to being fixed in space. In a field campaign involving many balloons, slight variations in ground level winds at launch lead to trajectory patterns that we analyze to derive 3D maps of the vertical and horizontal wind profiles downwind of the launch area. Field campaigns are focused on likely sites for wind power generation and on facilities from which airborne particulates are emitted. We describe results of wind measurements in Utah near the cities of Clarkston, Logan, and Ogden. ValidWind is a relatively inexpensive wind sensor that is easily and rapidly transported and deployed at remote sites. It is an ideal instrument for wind prospecting to support early decisions required, for example, in siting meteorology towers. ValidWind provides high-resolution, real time characterization of the average and changing 3D wind fields in which wind power turbines and other remote sensors must operate.

  4. Cooling Tower Considerations for Energy Optimizations 

    E-print Network

    Burger, R.

    1986-01-01

    and cellular fill installation. In this Refinery cooling tower (Figure 4) 25,000 gallons per minute of circulating water required a design of 10S°F entering water and .88OF discharge water at an 80°F inlet ambient temperature. The tower consisted of three... produce a sufficlent level of cooling. The retrofit consisted of Imtallirq square spray ABS nonclogglng nozzles and a five foot depth of cellular fill (Flgwre 5) havlng a large flute width of 1.90 inches and separation between layers for possible...

  5. Forecasting Cool Season Daily Peak Winds at Kennedy Space Center and Cape Canaveral Air Force Station

    NASA Technical Reports Server (NTRS)

    Barrett, Joe, III; Short, David; Roeder, William

    2008-01-01

    The expected peak wind speed for the day is an important element in the daily 24-Hour and Weekly Planning Forecasts issued by the 45th Weather Squadron (45 WS) for planning operations at Kennedy Space Center (KSC) and Cape Canaveral Air Force Station (CCAFS). The morning outlook for peak speeds also begins the warning decision process for gusts ^ 35 kt, ^ 50 kt, and ^ 60 kt from the surface to 300 ft. The 45 WS forecasters have indicated that peak wind speeds are a challenging parameter to forecast during the cool season (October-April). The 45 WS requested that the Applied Meteorology Unit (AMU) develop a tool to help them forecast the speed and timing of the daily peak and average wind, from the surface to 300 ft on KSC/CCAFS during the cool season. The tool must only use data available by 1200 UTC to support the issue time of the Planning Forecasts. Based on observations from the KSC/CCAFS wind tower network, surface observations from the Shuttle Landing Facility (SLF), and CCAFS upper-air soundings from the cool season months of October 2002 to February 2007, the AMU created multiple linear regression equations to predict the timing and speed of the daily peak wind speed, as well as the background average wind speed. Several possible predictors were evaluated, including persistence, the temperature inversion depth, strength, and wind speed at the top of the inversion, wind gust factor (ratio of peak wind speed to average wind speed), synoptic weather pattern, occurrence of precipitation at the SLF, and strongest wind in the lowest 3000 ft, 4000 ft, or 5000 ft. Six synoptic patterns were identified: 1) surface high near or over FL, 2) surface high north or east of FL, 3) surface high south or west of FL, 4) surface front approaching FL, 5) surface front across central FL, and 6) surface front across south FL. The following six predictors were selected: 1) inversion depth, 2) inversion strength, 3) wind gust factor, 4) synoptic weather pattern, 5) occurrence of precipitation at the SLF, and 6) strongest wind in the lowest 3000 ft. The forecast tool was developed as a graphical user interface with Microsoft Excel to help the forecaster enter the variables, and run the appropriate regression equations. Based on the forecaster's input and regression equations, a forecast of the day's peak and average wind is generated and displayed. The application also outputs the probability that the peak wind speed will be ^ 35 kt, 50 kt, and 60 kt.

  6. LARGE SCALE DEPLOYMENT OF RENEWABLE ENERGY BY COMBINING WIND FARMS WITH SOLAR THERMAL POWER PLANTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The installation of megawatt-size wind turbines on 65 to 80 meter towers at Class 4 wind sites in Texas has resulted in the cheapest form of renewable energy ($0.04/kWh). However, wind farm output has a diurnal mismatch to the utility electrical loading. Combining solar thermal power plants with w...

  7. Influences of offshore environmental conditions on wind shear profile parameters in Nantucket Sound

    E-print Network

    Massachusetts at Amherst, University of

    on offshore data collected for the Cape Wind project in Nantucket Sound, off the coast of Massachusetts unusable. SITE AND DATA The data [3] used in this project were taken at a tower owned by Cape WindInfluences of offshore environmental conditions on wind shear profile parameters in Nantucket Sound

  8. Wind Energy Opportunities, Challenges, and Progress Within the Federal Government (Poster)

    SciTech Connect

    Robichaud, R.

    2009-05-01

    Wind Powering America (WPA) works with Federal agencies to increase their understanding of wind resources and assessment; facilitate project development activities through Met tower loans, wind data analysis, and technical assistance; and provide advice on RFP development and financing options. This poster provides an overview of WPA's activities with the federal sector.

  9. Inspection techniques for wind turbine blades using ultrasound and sound waves

    Microsoft Academic Search

    Anne JUENGERT; Christian U. GROSSE

    Facing the climate change the use of renewable energies gains in importance. Especially wind energy will play a major role in the power supply in Central Europe. Due to the increasing number of installed wind energy plants, regular inspections are necessary to avoid accidents. Besides the tower and the gear, the wind turbine blades are highly stressed parts. Suitable non-destructive

  10. VIEW FROM DIVE TOWER CONFERENCE ROOM FACING NORTH (FIRST FLIGHT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW FROM DIVE TOWER CONFERENCE ROOM FACING NORTH (FIRST FLIGHT OF STAIRS) - U.S. Naval Base, Pearl Harbor, Submarine Dive Tower, Intersection of Clark & Morton Streets, Pearl City, Honolulu County, HI

  11. 14. CLOSEUP VIEW OF WINDOW IN SIGNAL TOWER OFFICE FACING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. CLOSE-UP VIEW OF WINDOW IN SIGNAL TOWER OFFICE FACING WEST. - U.S. Naval Base, Pearl Harbor, Signal Tower, Corner of Seventh Street & Avenue D east of Drydock No. 1, Pearl City, Honolulu County, HI

  12. 9. VIEW OF ENTRANCE TO SIGNAL TOWER OFFICE AT TOP ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. VIEW OF ENTRANCE TO SIGNAL TOWER OFFICE AT TOP OF ELEVATOR FACING NORTHWEST. - U.S. Naval Base, Pearl Harbor, Signal Tower, Corner of Seventh Street & Avenue D east of Drydock No. 1, Pearl City, Honolulu County, HI

  13. 1. Perspective of Mattes Street Signal Tower looking southwest. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Perspective of Mattes Street Signal Tower looking southwest. - Delaware, Lackawanna & Western Railroad, Scranton Yards, Mattes Street Signal Tower, 80 feet Southwest of Railroad Alley & Cedar Avenue, Scranton, Lackawanna County, PA

  14. 12. GENERAL INTERIOR VIEW OF SIGNAL TOWER OFFICE FACING NORTH. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. GENERAL INTERIOR VIEW OF SIGNAL TOWER OFFICE FACING NORTH. - U.S. Naval Base, Pearl Harbor, Signal Tower, Corner of Seventh Street & Avenue D east of Drydock No. 1, Pearl City, Honolulu County, HI

  15. 6. Detail of windows in north wall of Signal Tower. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. Detail of windows in north wall of Signal Tower. - Delaware, Lackawanna & Western Railroad, Scranton Yards, Mattes Street Signal Tower, 80 feet Southwest of Railroad Alley & Cedar Avenue, Scranton, Lackawanna County, PA

  16. 4. VIEW, LOOKING SOUTHEAST, SHOWING NORTHWEST ELEVATION OF TOWER ND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. VIEW, LOOKING SOUTHEAST, SHOWING NORTHWEST ELEVATION OF TOWER ND SIGNAL BRIDGE No. 6 AND DWARF SIGNAL IN FOREGROUND - South Station Tower No. 1 & Interlocking System, Dewey Square, Boston, Suffolk County, MA

  17. 7. Detail of first floor doorway to Signal Tower. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Detail of first floor doorway to Signal Tower. - Delaware, Lackawanna & Western Railroad, Scranton Yards, Mattes Street Signal Tower, 80 feet Southwest of Railroad Alley & Cedar Avenue, Scranton, Lackawanna County, PA

  18. TOWER S389, MAGAZINES IN BACKGROUND. Naval Magazine Lualualei, West ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    TOWER S389, MAGAZINES IN BACKGROUND. - Naval Magazine Lualualei, West Loch Branch, Guard-Watch Tower Type, Near A Avenue between Fourth & Sixth Streets, Ninth Street & D Avenue intersection, & F Avenue, Pearl City, Honolulu County, HI

  19. TOWER S389, WITH POLE. MAGAZINES IN BACKGROUND. Naval Magazine ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    TOWER S389, WITH POLE. MAGAZINES IN BACKGROUND. - Naval Magazine Lualualei, West Loch Branch, Guard-Watch Tower Type, Near A Avenue between Fourth & Sixth Streets, Ninth Street & D Avenue intersection, & F Avenue, Pearl City, Honolulu County, HI

  20. INTERIOR OF SA WETSIDE BUILDING. TOP OF CARBONATION TOWERS (SOLVAY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR OF SA WETSIDE BUILDING. TOP OF CARBONATION TOWERS (SOLVAY TOWERS) PROBABLY SAME LEVEL AS NY-300-D-6 BUT OPPOSITE VIEW. - Solvay Process Company, SA Wetside Building, Between Willis & Milton Avenue, Solvay, Onondaga County, NY

  1. 50. NORTHERN VIEW OF NONEVAPORATIVE WASTE WATER TREATMENT COOLING TOWERS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    50. NORTHERN VIEW OF NON-EVAPORATIVE WASTE WATER TREATMENT COOLING TOWERS IN CENTER, AND EVAPORATIVE WASTE WATER COOLING TOWERS ON RIGHT. (Jet Lowe) - U.S. Steel Duquesne Works, Blast Furnace Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  2. North and west sides of the cooling tower, utility building ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    North and west sides of the cooling tower, utility building (building 2606) is in the background at right - March Air Force Base, Strategic Air Command, Cooling Tower, 5220 Riverside Drive, Moreno Valley, Riverside County, CA

  3. View from southwest to northeast of cooling towers for perimeter ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View from southwest to northeast of cooling towers for perimeter acquisition radar building and PAR power plant - Stanley R. Mickelsen Safeguard Complex, Cooling Tower, In Limited Access Area, between Service Roads D & A, Nekoma, Cavalier County, ND

  4. Interior of the mine observation tower building, showing the steel ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior of the mine observation tower building, showing the steel compass ring in the tower. View facing east - U.S. Naval Base, Pearl Harbor, Waipio Peninsula, Waipo Peninsula, Pearl City, Honolulu County, HI

  5. 3. General view showing north elevation of Shell Interlocking Tower ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. General view showing north elevation of Shell Interlocking Tower and electric relay station. - New York, New Haven, & Hartford Railroad, Shell Interlocking Tower, New Haven Milepost 16, approximately 100 feel east of New Rochelle Junction, New Rochelle, Westchester County, NY

  6. View uphill of single chair lift, tower 15 in foreground, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View uphill of single chair lift, tower 15 in foreground, TOWERS 16 and 17 in the distance, LOOKING SOUTH. - Mad River Glen, Single Chair Ski Lift, 62 Mad River Glen Resort Road, Fayston, Washington County, VT

  7. Digital places : rethinking urban elements : the case of the tower

    E-print Network

    Gichuhi, Christopher M. (Christopher Mwethera), 1976-

    2004-01-01

    Problem - How can we make working, living and all aspects of our life in the urban tower more palatable? How can we create environment at the urban tower scale. With technology as one of the biggest drivers of social and ...

  8. 29. Photocopy of 1921 photograph. Glass Negative Box IX, Tower ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    29. Photocopy of 1921 photograph. Glass Negative Box IX, Tower Grove, Missouri Botanical Garden. ITALIAN GARDEN AND NEW PALM HOUSE (DEMOLISHED), LOOKING NORTHEAST - Missouri Botanical Garden, 2345 Tower Grove Avenue, Saint Louis, Independent City, MO

  9. OVERVIEW OF VALVE TOWER FROM NORTHERN SIDE OF BASIN. VIEW ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    OVERVIEW OF VALVE TOWER FROM NORTHERN SIDE OF BASIN. VIEW FACING SOUTHWEST - Schofield Barracks Military Reservation, Ku Tree Reservoir, Valve Tower, Kalakoa Stream, East Range, Wahiawa, Honolulu County, HI

  10. OVERVIEW OF VALVE TOWER FROM EASTERN SIDE OF BASIN SHOWING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    OVERVIEW OF VALVE TOWER FROM EASTERN SIDE OF BASIN SHOWING BRIDGE SUPPORTS ON HILLTOP. VIEW FACING WEST - Schofield Barracks Military Reservation, Ku Tree Reservoir, Valve Tower, Kalakoa Stream, East Range, Wahiawa, Honolulu County, HI

  11. APPROACH BRIDGE PORTION OF VALVE TOWER FOOT BRIDGE, AS SEEN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    APPROACH BRIDGE PORTION OF VALVE TOWER FOOT BRIDGE, AS SEEN FROM ENTRY. VIEW FACING NORTHWEST - Schofield Barracks Military Reservation, Ku Tree Reservoir, Valve Tower Foot Bridge, Kalakoa Stream, East Range, Wahiawa, Honolulu County, HI

  12. 155. Copy of Louis Rosenberg Etching (original in the Tower ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    155. Copy of Louis Rosenberg Etching (original in the Tower City Development Office) EXCAVATION OF TRACK AREA TO THE SOUTH OF HURON ROAD, VIEW WEST TO EAST - Terminal Tower Building, Cleveland Union Terminal, 50 Public Square, Cleveland, Cuyahoga County, OH

  13. TOWER, WEST ELEVATION, SHOWING CONNECTION PIPES FOR TURNOUTS 22 (FOREGROUND) ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    TOWER, WEST ELEVATION, SHOWING CONNECTION PIPES FOR TURNOUTS 22 (FOREGROUND) AND 24. NOTE ?LAZY JACK? TEMPERATURE COMPENSATOR IN FOREGROUND. - Baltimore & Ohio Railroad, Z Tower, State Route 46, Keyser, Mineral County, WV

  14. 8. LOOKING EAST FROM TOP OF WATER TOWER: VIEW SHOWS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. LOOKING EAST FROM TOP OF WATER TOWER: VIEW SHOWS BUILDING #626 AND PORTION OF QUADRANGLE - Fort Sam Houston, San Antonio Depot, Water-Watch Tower, Grayson Street & New Braunfels Avenue, San Antonio, Bexar County, TX

  15. S316, GUARD TOWER ON KOLEKOLE PASS RD. Naval Magazine ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    S316, GUARD TOWER ON KOLEKOLE PASS RD. - Naval Magazine Lualualei, Headquarters Branch, Guard-Watch Tower Type, Off Dent Road & on Kolekole Road near north boundary of installation, Pearl City, Honolulu County, HI

  16. TOWER 450 WITH POLE. Naval Magazine Lualualei, West Loch ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    TOWER 450 WITH POLE. - Naval Magazine Lualualei, West Loch Branch, Guard-Watch Tower Type, Near A Avenue between Fourth & Sixth Streets, Ninth Street & D Avenue intersection, & F Avenue, Pearl City, Honolulu County, HI

  17. S316, GUARD TOWER INTERIOR. Naval Magazine Lualualei, Headquarters Branch, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    S316, GUARD TOWER INTERIOR. - Naval Magazine Lualualei, Headquarters Branch, Guard-Watch Tower Type, Off Dent Road & on Kolekole Road near north boundary of installation, Pearl City, Honolulu County, HI

  18. 3. View looking E from top of World Trade Tower ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. View looking E from top of World Trade Tower with World Trade Tower parapet in foreground. Jet Lowe, photographer, 1982. - Brooklyn Bridge, Spanning East River between Park Row, Manhattan and Sands Street, Brooklyn, New York, New York County, NY

  19. 10. View west along carillon tower axis from base of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. View west along carillon tower axis from base of tower to gates in western estate wall at SR 141 - A. I. Du Pont Estate, Junction of State Route 141 & Rockland Road, Wilmington, New Castle County, DE

  20. View of the campanile and southeast tower looking from the ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of the campanile and southeast tower looking from the south tower roof (duplicate of HABS No. DC-141-40) - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  1. Large Wind Energy Converter: Growian 3 MW

    NASA Technical Reports Server (NTRS)

    Feustel, J. E.; Helm, S.; Koerber, F.

    1980-01-01

    The final report on the projected application of larger-scale wind turbine on the northern German coast is summarized. The designs of the tower, machinery housing, rotor, and rotor blades are described accompanied various construction materials are examined. Rotor blade adjustment devices auxiliary and accessory equipment are examined.

  2. Update on the Purdue University 2-second Drop Tower

    NASA Astrophysics Data System (ADS)

    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 an update on progress for the micro-gravity community. The most noticeable current activity is testing of the air-bag decelerator. The tower is one that will use a free-falling experiment inside of a drag shield to avoid most aerodynamic drag. The airbag is designed from experiences of others yet the small, triangular room in which the tower terminates imposes challenges. The airbag is approximately 1.5m diameter and 1.5m tall. Initial testing led to a desire to increase vent area, and just this week the bag has returned from the shop that was modifying it. On-board computer, battery packs, lighting, and cameras have been acquired. Thanks to Lockheed Martin, one camera is 500 frames per second with 1.3 million 12-bit gray scale pixels per frame. The Spincraft company donated steel hemisphere-cylinders to serve as the nose of the drag shield. Wind tunnel and CFD modeling of the drag shield has been performed by Purdue undergraduate aerospace students. Currently the drag shield structure and experiment package structure are being design and analyzed. The experiment volume is approximately a cylinder 0.45m diameter and 0.6m tall. Tower operation is intended to commence in fall 2010 with inert package drops at full mass and full height. Developing the operations procedures, especially operational safety, are the goals of this work. First science is then expected in the winter. References 1. Y. Chen, "A Study of Capillary Flow in a Vane-wall Gap in Zero Gravity," Ph.D. thesis, School of Aeronautics and Astronautics, Purdue University. August 2003. 2. Y. Chen and S. H. Collicott, "Investigation of the Symmetric Wetting of a Vane-Wall Gap in Propellant Tanks," AIAA Journal, 42, No. 2, pp. 305-314, February 2004. 3. Y. Chen, and S. H. Collicott, "Experimental Study on the Capillary Flow in a Vane-Wall Gap Geometry," AIAA Journal, 43, No. 11, pp. 2395-2403, November, 2005. 4. Y. Chen and S. H. Collicott, "Study of Wetting in an Asymmetrical Vane-Wall Gap in Propellant Tanks," AIAA Journal, 44, 4, pp. 859-867, April 2006. 5. S. L. F

  3. Input turbulence features at a megawatt-size wind turbine, Medicine Bow, Wyoming

    SciTech Connect

    Connell, J.R.; Morris, V.R.; Hinchee, M.E.

    1986-12-01

    In response to recent observations that wind turbulence has a strong effect on wind turbine fatigue life, measurements of turbulent wind velocity profiles have been made at the Medicine Bow, Wyoming, WTS-4 wind turbine site. These measurements were taken at seven levels spanning the WTS-4 rotor height on a single meteorological tower 1.75 rotor diameters upstream of the turbine. Concurrent measurements of rotor response were also made. Analysis of the winds at the Medicine Bow site reveals the influence of atmospheric and geographic conditions on what may at first glance appear to be a 'classic, simple, flat terrain' case. The turbulence data are then analyzed to (1) characterize the wind in terms of fixed-point, single-tower properties and (2) model the wind properties as they would be experienced by points on rotating turbine blades. The STRS-2 model, developed by the Pacific Northwest Laboratory, is used to convert single-tower wind characteristics into those that would be measured from an array of towers arranged in a crosswind line covering the rotor disk. A response function for the flatwise root bending moment of one of the WTS-4 turbine blades is computed using the turbine data and the STRS-2 data. The STRS-2 model provides a substantially improved correlation with wind turbine blade bending moment over other single-tower estimation methods. 14 refs., 10 figs., 1 tab.

  4. Input turbulence features at a megawatt-size wind turbine at Medicine Bow, Wyoming

    SciTech Connect

    Connell, J.R.; Morris, V.R.; Hinchee, M.E.

    1989-02-01

    In response to recent observations that wind turbulence has a strong effect on wind turbine fatigue life, measurements of turbulent wind velocity profiles have been made at the Medicine Bow, Wyo., WTS-4 wind turbine site. These measurements were taken at seven levels spanning the WTS-4 rotor height on a single meteorological tower 1.75 rotor diameters upstream of the turbine. Concurrent measurements of rotor response were also made. Analysis of the winds at the Medicine Bow site reveals the influence of atmospheric and geographic conditions on what may, at first glance, appear to be a classic, simple, flat terrain case. The turbulence data are analyzed to (1) characterize the wind in terms of fixed-point, single-tower properties and (2) model the wind properties as they would be experienced by points on rotating turbine blades. The STRS-2 model, developed by the Pacific Northwest Laboratory, is used to convert single-tower wind characteristics into an estimate of those that would be measured from an array of towers arranged in a crosswind line covering the rotor disk. A response function for the flatwise root bending moment of one of the WTS-4 turbine blades is computed using the turbine data and the STRS-2 data. The STRS-2 model provides a substantially improved correlation with wind turbine blade bending moment over other single-tower estimation methods.

  5. Monitoring the dynamic of suspended sediment using tower-based water spectrum observing system in the Hangzhou Bay

    NASA Astrophysics Data System (ADS)

    Dai, Qian; Gong, Fang; Huang, Haiqing; He, Xianqiang; Chen, Jianyu; Zhu, Qiankun

    2014-10-01

    Dynamic variations of suspended sediment (TSM) in extremely turbid waters of Hangzhou Bay (HZB) have been studied using a tower-based high-frequency water-spectrum observing system. We developed a practical data processing method for the high-frequency water-spectrum observation. In addition, the method was validated by the ASD measurement, and the results showed that the tower-measured normalized water-leaving radiance was consistent with it measured by ASD, with the correlation coefficient greater than 0.90 and the mean relative error of 6.48%. Based on the tower-measured water spectrum, the TSM was retrieved further with high frequency, and the results showed that the TSM in the HZB had significant diurnal and seasonal variations. The diurnal dynamics might mainly be caused by tidal induced resuspension, yet the seasonal variations might be derived by winds largely.

  6. Earthquake resistant design of intake--outlet towers

    Microsoft Academic Search

    A. K. Chopra; C. Y. Liaw

    1975-01-01

    The problem of designing reinforced concrete intake-outlet towers, partially submerged in water, to withstand earthquake ground motion is examined in general terms. It is shown that water surrounding the towers as well as the water inside them significantly affects the response to ground motion and that these hydrodynamic effects should be considered in the design of towers. A rational method

  7. Legionnaires' disease outbreaks and cooling towers with amplified Legionella concentrations

    Microsoft Academic Search

    Brian G. Shelton; W. Dana Flanders; George K. Morris

    1994-01-01

    This study was designed to investigate the possible association of high colony counts of legionellae from cooling towers and evaporative condensers with Legionnaires' disease outbreaks. We obtained legionellae counts from samples of cooling towers and evaporative condensers that were the likely sources of two different Legionnaires' disease outbreaks and compared these counts with those from cooling towers that were not

  8. Improving the efficiency of natural draft cooling towers

    Microsoft Academic Search

    J. Smrekar; J. Oman; B. Širok

    2006-01-01

    This study shows how the efficiency of a natural draft cooling tower can be improved by optimising the heat transfer along the cooling tower (CT) packing using a suitable water distribution across the plane area of the cooling tower. On the basis of cooling air measurements, it is possible to distribute the water in such a way that it approaches

  9. Energy and Mass Transfer Phenomena in Natural Draft Cooling Towers

    Microsoft Academic Search

    B. Sirok; B. Blagojevic; M. Novak; M. Hocevar; F. Jere

    2003-01-01

    In this paper, the development of natural draft cooling towers diagnostics is presented. Diagnostic method is based on measurements of velocity and temperature fields of the airflow in the entire surface area of cooling tower and the raised phenomenological model of heat and mass transfer in a selected reference vertical segment of cooling tower. Velocity and temperature fields of the

  10. Performance characteristics of counter flow wet cooling towers

    Microsoft Academic Search

    Jameel-Ur-Rehman Khan; M. Yaqub; Syed M. Zubair

    2003-01-01

    Cooling towers are one of the biggest heat and mass transfer devices that are in widespread use. In this paper, we use a detailed model of counter flow wet cooling towers in investigating the performance characteristics. The validity of the model is checked by experimental data reported in the literature. The thermal performance of the cooling towers is clearly explained

  11. An investigation into a falling film type cooling tower

    Microsoft Academic Search

    M. Z Anabtawi

    1995-01-01

    A model for a falling film type cooling tower has been developed to investigate the effect of tower parameters as well as the effect of liquid-side thermal resistance on the tower performance. The energy equation is used to determine the temperature distribution across the liquid film. The heat and mass transfer processes between the liquid film and air bulk are

  12. Initial Model For Fires In The World Trade Center Towers

    Microsoft Academic Search

    Ronald G. Rehm; William M. Pitts; Howard R. Baum; David D. Evans; Kuldeep Prasad; Kevin B. McGrattan; Glenn P. Forney

    2003-01-01

    Based on preliminary assumptions and analysis, mathematical models have been used to estimate the behavior of the fires in the twin towers of the World Trade Center (WTC) on September 11, 2001. The hijacked-plane collision with each tower produced significant structural damage, generated a spectacular external fireball, and started burning within the tower. The fuel consumed by the fireball was

  13. 14. General oblique view of Shell Interlocking Tower, north and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. General oblique view of Shell Interlocking Tower, north and west facades, showing over head catenary tower and bridge at right. - New York, New Haven, & Hartford Railroad, Shell Interlocking Tower, New Haven Milepost 16, approximately 100 feel east of New Rochelle Junction, New Rochelle, Westchester County, NY

  14. 6. Detail of northeast corner of Shell Interlocking Tower, showing ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. Detail of northeast corner of Shell Interlocking Tower, showing ornamental east concrete beltcourse and tower shield with bronze numerals. - New York, New Haven, & Hartford Railroad, Shell Interlocking Tower, New Haven Milepost 16, approximately 100 feel east of New Rochelle Junction, New Rochelle, Westchester County, NY

  15. Crosswind and internal flow characteristics of dry cooling towers

    Microsoft Academic Search

    C. M. B. Russell; T. V. Jones; D. W. Holder; H. R. McChesney; M. Verlinden

    1977-01-01

    Experiments are described which were performed to determine how the arrangement of heat exchanger bundles at the base of a natural draft dry cooling tower affects the tower's internal flow and its sensitivity to crosswinds. Model towers with heat exchanger bundles represented by gauze screens were used in tests with no crosswinds at high Re numbers and with crosswind effects

  16. Computerized engineering model for evaporative water cooling towers

    Microsoft Academic Search

    J. E. Park; J. M. Vance; K. E. Cross; N. H. Van Wie

    1978-01-01

    The evaporative cooling tower is often used to reject waste heat from industrial processes, especially power plants and chemical facilities. In particular, huge cooling towers are used for heat rejection from gaseous diffusion plants. The ability to analyze and\\/or predict the performance of these towers is an important process engineering function. A consistent physical model for crossflow and counterflow cooling

  17. Transmission Line Tower-Analysis and Design in Review

    Microsoft Academic Search

    R. A. Kravitz

    1982-01-01

    This paper presents a review of the state of the art and practice of transmission line tower design with specific attention to structure loading conditions, comparison of results using different tower analysis techniques and a commentary on some criteria of the ASCE Manual 52 ''Guide For Design of Steel Transmission Towers.'' This paper also discusses some of the items causing

  18. TOWER OF LIGHT AND MAYA'S TAKE AWAY RETAIL OUTLET

    E-print Network

    TOWER OF LIGHT AND MAYA'S TAKE AWAY RETAIL OUTLET SCOPE OF WORK 19 July 2013 Tower of Light and Maya's Take away Scope of work Final.docx Page 1 1. Introduction The Tower of Lights is a small tuck cooking or must be supported by the kitchen at Mayas. MAYA'S Take Away is a small fast food facility

  19. 36 CFR 7.30 - Devils Tower National Monument.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 2011-07-01 false Devils Tower National Monument. 7.30 Section...THE NATIONAL PARK SYSTEM § 7.30 Devils Tower National Monument. (a) Climbing...any climbing above the talus slopes on Devils Tower. The registrant is also...

  20. 36 CFR 7.30 - Devils Tower National Monument.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 2013-07-01 false Devils Tower National Monument. 7.30 Section...THE NATIONAL PARK SYSTEM § 7.30 Devils Tower National Monument. (a) Climbing...any climbing above the talus slopes on Devils Tower. The registrant is also...

  1. 36 CFR 7.30 - Devils Tower National Monument.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 2010-07-01 false Devils Tower National Monument. 7.30 Section...THE NATIONAL PARK SYSTEM § 7.30 Devils Tower National Monument. (a) Climbing...any climbing above the talus slopes on Devils Tower. The registrant is also...

  2. 36 CFR 7.30 - Devils Tower National Monument.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 2014-07-01 false Devils Tower National Monument. 7.30 Section...THE NATIONAL PARK SYSTEM § 7.30 Devils Tower National Monument. (a) Climbing...any climbing above the talus slopes on Devils Tower. The registrant is also...

  3. 36 CFR 7.30 - Devils Tower National Monument.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 2012-07-01 false Devils Tower National Monument. 7.30 Section...THE NATIONAL PARK SYSTEM § 7.30 Devils Tower National Monument. (a) Climbing...any climbing above the talus slopes on Devils Tower. The registrant is also...

  4. Tower of Hanoi: Evidence for the Cost of Goal Retrieval

    Microsoft Academic Search

    John R. Anderson; Scott Douglass

    2001-01-01

    Past research on the Tower of Hanoi problem has provided clear evidence for the importance of goal–subgoal structures in problem solving. However, the nature of the traditional Tower of Hanoi problem makes it impossible to determine whether there is any special cost associated with storing or retrieving goals. A variation of the Tower of Hanoi problem is described that allows

  5. Dynamic responses analysis and disaster prevention of transmission line under strong wind

    Microsoft Academic Search

    Jingbo Yang; Fengli Yang; Qinghua Li; Dongjie Fu; Zifu Zhang

    2010-01-01

    Dynamic analysis of a typical transmission line section under strong wind was carried out. Firstly, according to the design conditions of the typical transmission line section, a three dimensional finite element analysis model of cup tower-stay frame tower-conductor-ground wire-insulator system was established in ANSYS. The initial tension force of the conductors was applied by the cooling method. Before the wind-induced

  6. Cooling Towers--Energy Conservation Strategies Preservative Spray Treatment Maintains Cooling Tower

    E-print Network

    Reidenback, R.

    Several problems common to most industrial wood framed cooling towers can be easily controlled with annual preservative spray treatment applications to the plenum area framework and drift eliminators. It eliminates the expensive periodic repairs due...

  7. Cooling Towers--Energy Conservation Strategies Preservative Spray Treatment Maintains Cooling Tower 

    E-print Network

    Reidenback, R.

    1991-01-01

    Several problems common to most industrial wood framed cooling towers can be easily controlled with annual preservative spray treatment applications to the plenum area framework and drift eliminators. It eliminates the expensive periodic repairs due...

  8. Queensland University of Technology Drop Tower Facility

    NASA Astrophysics Data System (ADS)

    Plagens, Owen; Hales, Matthew; Castillo, Martin; Steinberg, Theodore

    2012-07-01

    The Queensland University of Technology (QUT) Drop Tower Facility provides access to an inexpensive high quality reduced gravity test environment. This facility is available to and has been used by number of nationally and internationally based organisations, along with researchers from QUT, for scientific and industry related research. The drop tower, located in Brisbane, Australia, allows 2.0 seconds of high quality reduced gravity (˜0.001 g). The cylindrical drop package has a maximum rating of 200 kg with dimensions of 0.8 m diameter and 0.9 m high, and experiences a maximum deceleration of ˜30 g. Current research projects being carried out at the QUT Drop Tower Facility include research in the areas of self-propagating high-temperature synthesis of materials, combustion and fire safety, flammability of metals, characterisation of combustion products, and sol-gel nanomaterials. Keywords: Reduced gravity, microgravity, drop tower, zero gravity, low gravity, combustion, combustion products, nanomaterials, sol-gel, flammability, high temperature synthesis.

  9. Optimized Pointing Strategies for Solar Tower ACTs

    NASA Astrophysics Data System (ADS)

    Scalzo, R. A.; Boone, L.M.; Bramel, D.; Carson, J.; Covault, C.E.; Fortin, P.; Gaunthier, G.; Gingrich, D.; Hanna, D.; Jarvis, A.; Kildea, J.; Mueller, C.; Mukherjee, R.; Ong, R.A.; Ragan, K.; Williams, D.A.; Zweerink, J.

    2003-07-01

    We discuss simulations of novel heliostat pointing configurations designed to improve the angular and energy resolution of a solar tower wavefront-sampling atmospheric Cherenkov telescope. One such configuration will be tested via observations of the Crab Nebula with the STACEE detector in the fall of 2003.

  10. Balsa Tower Walls Brave "Big Buster"

    ERIC Educational Resources Information Center

    Granlund, George

    2008-01-01

    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,…

  11. On the optimum sizing of cooling towers

    Microsoft Academic Search

    M. S Söylemez

    2001-01-01

    The optimum heat and mass transfer area at which minimum cost exists throughout the technical life of forced draft counter-current cooling towers is studied in the present work. Original formulae are developed and presented for the best thermoeconomical performance as a design point.

  12. CFD simulation of wet cooling towers

    Microsoft Academic Search

    Rafat Al-Waked; Masud Behnia

    2006-01-01

    Heat and mass transfer inside a natural draft wet cooling tower (NDWCT) have been investigated numerically under different operating and crosswind conditions. The three-dimensional CFD model has utilized the standard k–? turbulence model as the turbulence closure. The current simulation has adopted both the Eulerian approach for the air phase and the Lagrangian approach for the water phase. The film

  13. Drop tower with no aerodynamic drag

    NASA Technical Reports Server (NTRS)

    Kendall, J. M., Jr.

    1981-01-01

    Cooling air accelerated to match velocity of falling object eliminates drag. 3 meter drop tower with suction fan and specific geometry causes air to accelerate downward at 1 g. Although cooling of molten material released from top is slow because surrounding air moves with it, drop remains nearly spherical.

  14. WET/DRY COOLING TOWER TEST MODULE

    EPA Science Inventory

    The report gives results of an evaluation of the engineering performance of a single-cell wet/dry cooling tower (about 25 MW) in an 18-month field test at San Bernardino, CA. Test objectives included determination of the water conservation and operating characteristics, and verif...

  15. The Legacy of the Texas Tower Sniper

    ERIC Educational Resources Information Center

    Lavergne, Gary

    2007-01-01

    In this article, the author relates the incident that happened at the University of Texas to the tragedy that took place at Virginia Tech. On August 1, 1966, Charles Joseph Whitman ascended the University of Texas Tower, in Austin, and in 96 minutes fired 150 high-powered rounds of ammunition down upon an unsuspecting university family. The…

  16. The Tower and Glass Marbles Problem

    ERIC Educational Resources Information Center

    Denman, Richard T.; Hailey, David; Rothenberg, Michael

    2010-01-01

    The Catseye Marble company tests the strength of its marbles by dropping them from various levels of their office tower, to find the highest floor from which a marble will not break. We find the smallest number of drops required and from which floor each drop should be made. We also find out how these answers change if a restriction is placed on…

  17. Tower Power: Producing Fuels from Solar Energy

    ERIC Educational Resources Information Center

    Antal, M. J., Jr.

    1976-01-01

    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)

  18. Influence of Flow Rotation Within a Cooling Tower on the Aerodynamic Interaction with Crosswind Flow

    NASA Astrophysics Data System (ADS)

    Kashani, M. M. Hemmasian; Dobrego, K. V.

    2014-03-01

    Environmental crosswind changes the aerodynamic pattern inside a cooling tower, destroys uniform and axisymmetric distribution of flow at its inlet and outlet, and may degrade fill zone performance. In this paper, the effect of flow rotation in the over-shower zone of a natural draft cooling tower (NDCT) on the aerodynamic interaction with crosswind is studied numerically. The 3D geometry of an actual NDCT and three models of induced rotation velocity fields are utilized for simulation. It is demonstrated that flow rotation results in homogenization of the aerodynamic field in the over-shower zone. The inhomogeneity of the velocity field in the outlet cross section decreases linearly with rotation intensification. The effect of main stream switching under strong wind conditions is found. It is shown that even moderate flow rotation eliminates this effect.

  19. ETR COOLING TOWER. PUMP HOUSE (TRA645) IN SHADOW OF TOWER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    ETR COOLING TOWER. PUMP HOUSE (TRA-645) IN SHADOW OF TOWER ON LEFT. AT LEFT OF VIEW, HIGH-BAY BUILDING IS ETR. ONE STORY ATTACHMENT IS ETR ELECTRICAL BUILDING. STACK AT RIGHT IS ETR STACK; MTR STACK IS TOWARD LEFT. CAMERA FACING NORTHEAST. INL NEGATIVE NO. 56-3799. Jack L. Anderson, 11/26/1956 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  20. Power coefficient of tornado-type wind turbines

    SciTech Connect

    Rangwalla, A.A.; Hsu, C.T.

    1983-11-01

    In a tornado-type wind turbine the wind collecting tower is equipped with adjustable vanes that can be opened on the windward side and closed on the leeward side. The wind enters the tower tangentially through these open vanes and exits from the top. As a result, a vortex is formed inside the tower. A vertical axis turbine which is located underneath the tower floor admits air vertically and exhausts it into the vortex core. The pressure drop in the vortex core can be high, depending upon the vortex concentration, thus enhancing manyfold the total pressure drop across the turbine. The power coefficient C /SUB p/ of this system depends mainly on how low a pressure can be created in the vortex core. A maximum C /SUB p/ of about 2.5 was obtained by Yen for a spiral shaped tower. This is about 6.25 times the C /SUB p/ of conventional windmills. Analytical studies have been carried out by several investigators to study the C /SUB p/ of this vortex machine. Loth considered the conservation of angular momentum and obtained a C /SUB p/ based on the tower frontal area, which is not impressive.

  1. Wind Power Prediction by a New Forecast Engine Composed of Modified Hybrid Neural Network and Enhanced Particle Swarm Optimization

    Microsoft Academic Search

    Nima Amjady; Farshid Keynia; Hamidreza Zareipour

    2011-01-01

    Following the growing share of wind energy in elec- tric power systems, several wind power forecasting techniques have been reported in the literature in recent years. In this paper, a wind power forecasting strategy composed of a feature selection component and a forecasting engine is proposed. The feature se- lection component applies an irrelevancy filter and a redundancy filter to

  2. Multi-converter operation of variable speed wind turbine driving permanent magnet synchronous generator during network fault

    Microsoft Academic Search

    S. M. Muyeen; R. Takahashi; T. Murata; J. Tamura

    2009-01-01

    The full or partial rating frequency converters, in general, are used widely for the operation of variable speed wind turbine (VSWT) driven wind generators. Among the variable speed wind generators, permanent magnet synchronous generator (PMSG) which uses a full rating frequency converter for grid interfacing is drawing much attention nowadays due to its some salient features. However, considering the factors

  3. Aerodynamic interference between two Darrieus wind turbines

    SciTech Connect

    Schatzle, P.R.; Klimas, P.C.; Spahr, H.R.

    1980-01-01

    The effect of aerodynamic interference on the performance of two curved bladed Darrieus-type vertical axis wind turbines has been calculated using a vortex/lifting line aerodynamic model. The turbines have a tower-to-tower separation distance of 1.5 turbine diameters, with the line of turbine centers varying with respect to the ambient wind direction. The effects of freestream turbulence were neglected. For the cases examined, the calculations showed that the downwind turbine power decrement (1) was significant only when the line of turbine centers was coincident with the ambient wind direction, (2) increased with increasing tip-speed-ratio, and (3) is due more to induced flow angularities downstream than to speed deficits near the downstream turbine.

  4. Wind Turbines Adaptation to the Variability of the Wind Field

    NASA Astrophysics Data System (ADS)

    Ulianov, Yuriy; Martynenko, Gennadii; Misaylov, Vitaliy; Soliannikova, Iuliia

    2010-05-01

    WIND TURBINES ADAPTATION TO THE VARIABILITY OF THE WIND FIELD The subject of our scientific research is wind power turbines (WPT) with the horizontal axis which were now common in the world. Efficient wind turbines work is largely determined by non-stationarity of the wind field, expressed in its gustiness, the presence of vertical and horizontal shifts of wind speed and direction. At critical values of the wind parameters WPT has aerodynamic and mechanical overload, leading to breakdowns, premature wear and reduce the life of the wind turbine. To prevent accidents at the peak values of wind speed it is used the regulatory system of windwheels. WPT control systems provide a process orientation of the wind turbine rotor axis in the line of the mean wind. Wind turbines are also equipped with braking device used to protect against breakdowns when a significant increase in the wind. In general, all these methods of regulation are not always effective. Thus, in practice there may be situations when the wind speed is many times greater than the stated limit. For example, if there are microbursts in the atmospheric boundary layer, low-level wind shears caused by its gust front, storms, etc. It is required for a wind power turbine adaptation to intensive short-term wind impulses and considerable vertical wind shifts that the data about them shall be obtained ahead of time. To do this it is necessary to have the information on the real structure of the wind field in the area of the blade sweep for the minimum range against the wind that is determined by the mean speed and the system action time. The implementation of acoustic and laser traditional wind sounding systems is limited by ambient acoustic noise, by heavy rain, snowfall and by fog. There are free of these disadvantages the inclined radioacoustic sounding (IRASS) technique which works for a system of remote detection and control of wind gusts. IRASS technique is realized as low-potential Doppler pulse radar including combined RF-acoustic antenna installed coaxially with the gondola of the wind power turbine. The work of the technique is synchronized with rotation of blades to eliminate their shielding action. Dangerous in terms of dynamic strength is the wind load pulse, the rise time which is comparable with the period of the natural frequency of the wind turbine elements (blade, tower, rotor, etc.). The amplitude decay of resonant vibrations at critical values of the speed of rotation can be realized through the use of mechanical elastic supports with nonlinear artificial dampers. They have a high coefficient of resistance, but may cause self-excited oscillations. We propose the way to deal with raised vibration of wind turbine elements at the expense of short-term increase of damping in the range of critical rotary axis speeds or during impulsive effects of wind loadings (wind gusts). This is possible through the use of non-linear electromagnetic dampers or active magnetic bearings. Their feature is the possibility of varying the mechanical stiffness and damping properties by changing the electrical parameters of electromagnets. The controlling of these parameters is carried out by the control system (CS) with the information feedback on the spatial-temporal structure of the wind field obtained from IRASS. In the composition of the CS can also be included the rotational speed sensor of the WPT rotor. This approach to the adaptation of wind turbines will allow to reduce vibration and to perform early compensation of the load on their components, which arise under the wind gusts. In addition, corrections about the wind field obtained with IRASS, would increase the mean power of WPT.

  5. Natural draft dry cooling tower modelling

    NASA Astrophysics Data System (ADS)

    Tanimizu, K.; Hooman, K.

    2013-02-01

    Predictions based on a numerical simulation of a natural draft dry cooling tower (NDDCT) has been compared with those obtained theoretically and experimentally. Experiments are conducted in a lab-scale NDDCT and are validated with a three-dimensional numerical simulation of the flow in and around the heat exchangers, which is modelled as a porous medium. Both vertical and horizontal arrangements of the heat exchangers are examined. The experimental, numerical and theoretical approaches lead to very close prediction for the air velocity and temperature at the exit of the cooling tower. Results of this study are expected to be useful for future work on the development of air-cooled condensers for geothermal power plants in Australia.

  6. Warped Kaluza-Klein towers revisited

    SciTech Connect

    Grard, Fernand [Physique Generale et Physique des Particules Elementaires, Universite de Mons-Hainaut, 20 Place du Parc, 7000 Mons (Belgium); Nuyts, Jean [Physique Theorique et Mathematique, Universite de Mons-Hainaut, 20 Place du Parc, 7000 Mons (Belgium)

    2007-12-15

    Inspired by the warped Randall-Sundrum scenario proposed to solve the mass scale hierarchy problem with a compactified fifth extra dimension, a similar model with no metric singularities has been elaborated. In this framework, the Kaluza-Klein reduction equations for a real massless scalar field propagating in the bulk have been studied carefully from the point of view of Hermiticity so as to formulate in a mathematically rigorous way all the possible boundary conditions and corresponding mass eigenvalue towers and tachyon states. The physical masses as observable in our four-dimensional brane are deduced from these mass eigenvalues depending on the location of the brane on the extra dimension axis. Examples of mass towers and tachyons and related field probability densities are presented from numerical computations performed for some arbitrary choices of the parameters of the model.

  7. The IFSI Experimental Gravitation Group drop tower

    NASA Astrophysics Data System (ADS)

    Iafolla, Valerio; Fiorenza, Emiliano; Lefevre, Carlo; Nozzoli, Sergio; Peron, Roberto; Reale, Andrea; Santoli, Francesco

    The Experimental Gravitation Group of Istituto di Fisica dello Spazio Interplanetario (IFSI-INAF) has recently completed the development of a drop tower in its laboratories. This new facility is used in the context of the wide range of activities of the Group, in particular for testing high-sensitivity accelerometers and gradiometers. These instruments will be mainly operated in free fall conditions and this facility will be used for simulating these conditions. The tower has an height of 10 m (7-8 m effective fall height). Its capabilities include a magnetic release mechanism, a (variable acceleration) recovery system and will include a telemetry system. Following a description of the facility, the main foreseen uses will be discussed, among them: tests of accelerometer working position stability, release transient effects, capability of test mass initial attitude and angular velocity control, repeatability.

  8. 2/21/2014 Downsizing Wind Energyfor Your Phone | Glacial EnergyBlog -Commercial Electric Savings, Electric Provider, Electric Supplier http://blog.glacialenergy.com/2014/02/19/downsizing-wind-energy-for-your-phone/ 1/2

    E-print Network

    Chiao, Jung-Chih

    and portable size. A typical wind turbine these days is about 114 meters tall; the micro windmills Rao, they often envision the massive, towering wind turbines that line hilltops and shorelines, generating power and Chiao have developed are 1.8 mm tall. They are more than 63 thousand times smaller than a wind turbine

  9. Cooling Towers, The Neglected Energy Resource

    E-print Network

    Burger, R.

    practically non-clogging nozzles, Figure 4. An added advantage of this newer type nozzle is that maintenance and cleaning are greatly simplified due to upwards of 75% fewer nozzles required than the conventional small orifice conieal pattern spray units...-09-78 Proceedings from the Ninth Annual Industrial Energy Technology Conference, Houston, TX, September 16-18, 1987 Figure 4 Cellular fill and square spray non-clogging nozzles grantly mllximize performance ?of cooling towers. After sandblasting and coating...

  10. Graph Tower Dichromatic Polynomial Olivier Ramare

    E-print Network

    Ramaré, Olivier

    Graph Tower Dichromatic Polynomial Olivier Ramar´e UMR CNRS 8524 Universit´e de Lille I F-59655 - Villeneuve d'Ascq - France Olivier.Ramare@univ-lille1.fr Daniel Tanr´e UMR CNRS 8524 Universit´e de Lille I F-59655 - Villeneuve d'Ascq - France Daniel.Tanre@univ-lille1.fr March 25, 2008 Abstract Starting from

  11. Using Virtual Tall Tower [CO2] Data in Inverse Models to Reduce Uncertainty in Global and Regional Estimates of Carbon Flux

    Microsoft Academic Search

    J. Skidmore; A. Denning; K. R. Gurney; K. J. Davis; P. J. Rayner

    2003-01-01

    Previous studies in optimization of carbon observing networks considered any global grid cell as eligible for selection as a measurement site. In reality, measurement of mean CO2 over highly variable terrestrial regions is very impractical and expensive. A global network of eddy covariance flux towers already exists where continuous measurements of CO2 are taken, as well as measurements of sensible

  12. Investigations of the Tornado Wind-Energy System. Final report, September 1978-April 1980

    SciTech Connect

    Yen, J.T.

    1980-05-01

    Tornado-type Wind Energy Systems (TWES) use the core of a vortex in a hollow tower to provide a low pressure exhaust reservoir for a wind turbine. Wind tunnel data are presented, and previous and planned test programs are described, including the evolution of tower design from the spiral-cross-sectional design through the passive omnidirectional design to the fixed-vane omnidirectional design. A larger model with a 15-ft height tower and a 30-in. diameter turbine is described, including details on design, configuration, and instrumentation, plus details on the test-rig for testing the 30-in. turbine under a staight-flow environment. Results on turbine efficiency, tip-speed-ratio, and turbine disk loading coefficient are presented and discussed. A new cost analysis is presented that makes cost estimates for large TWES systems using the measured performance of small models without scaling laws, plus the tower cost estimates deduced from the simple structural anlaysis. (LEW)

  13. Legionella in Puerto Rico cooling towers

    SciTech Connect

    Negron-Alviro, A.; Perez-Suarez, I.; Hazen, T.C. [Univ. of Puerto Rico, Rio Piedras (Puerto Rico)

    1988-12-31

    Water samples from air conditioning cooling towers receiving different treatment protocols on five large municipal buildings in San Juan, Puerto Rico were assayed for various species and serogroups of Legionella spp. using direct immunofluorescence. Several water quality parameters were also measured with each sample. Guinea pigs were inoculated with water samples to confirm pathogenicity and recover viable organisms. Legionella pneumophila (1-6), L. bozemanii, L. micdadei, L. dumoffii, and L. gormanii were observed in at least one of the cooling towers. L. pneumophila was the most abundant species, reaching 10{sup 5} cells/ml, within the range that is considered potentially pathogenic to humans. A significantly higher density of L. pneumophila was observed in the cooling tower water that was not being treated with biocides. Percent respiration (INT) and total cell activity (AODC), were inversely correlated with bacterial density. This study demonstrates that Legionella spp. are present in tropical air-conditioning cooling systems, and without continuous biocide treatment may reach densities that present a health risk.

  14. Water-conserving cooling tower treatment

    SciTech Connect

    Mathie, A.J. [A.J. Mathie Company, Roy, UT (United States)

    1996-12-31

    Water conservation in cooling towers and evaporative coolers can finally become a reality. Also, fouled closed hot and chilled water systems can be restored to near original efficiency using the same technology. The barrier limiting the traditional water treatment industry from serious involvement in water conservation is the lack of a really good chemical to control scale. Poor scale inhibitors are the reason for a heavy bleed. Minerals concentrated by evaporation is wasted to the sewer while low solids make-up water fills the tower. Water conservation is important because of the increasing usable water shortage, the cost to add infrastructure to deliver increasing amounts of water to accommodate growth and the limitations imposed on disposal to the sewer. Now, due to innovations in chemical treatment, users of cooling towers and evaporative coolers can conserve water. In this presentation the author assumes the audience has some knowledge of traditional water treatment. Except for a few general references to establish common understanding, the author confines his remarks to discussing an advanced technology developed by DIAS, Inc., and the economics of its use.

  15. Large CO2 reductions via offshore wind power matched to inherent storage in energy end-uses

    E-print Network

    Jacobson, Mark

    develop methods for assessing offshore wind resources, using a model of the vertical structureLarge CO2 reductions via offshore wind power matched to inherent storage in energy end-uses Willett of the planetary boundary layer (PBL) over water and a wind- electric technology analysis linking turbine and tower

  16. BOREAS AFM-06 Mean Wind Profile Data

    NASA Technical Reports Server (NTRS)

    Wilczak, James; Hall, Forrest G. (Editor); Newcomer, Jeffrey A. (Editor); Smith, David E. (Technical Monitor)

    2000-01-01

    The Boreal Ecosystem-Atmosphere Study (BOREAS) Airborne Fluxes and Meteorology (AFM)-6 team from the National Oceanic and Atmospheric Administration/Environment Technology Laboratory (NOAA/ETL) operated a 915-MHz wind/Radio Acoustic Sounding System (RASS) profiler system in the Southern Study Area (SSA) near the Old Jack Pine (OJP) tower from 21 May 1994 to 20 Sep 1994. The data set provides wind profiles at 38 heights, containing the variables of wind speed; wind direction; and the u-, v-, and w-components of the total wind. The data are stored in tabular ASCII files. The mean wind profile data are available from the Earth Observing System Data and Information System (EOSDIS) Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC). The data files are available on a CD-ROM (see document number 20010000884).

  17. Dynamic blade loading in the ERDA/NASA 100 kW and 200 kW wind turbines

    NASA Technical Reports Server (NTRS)

    Spera, D. A.; Janetzke, D. C.; Richards, T. R.

    1977-01-01

    Dynamic blade loads, including aerodynamic, gravitational, and inertial effects, are presented for two large horizontal-axis wind turbines: the ERDA-NASA 100 kW Mod-0 and 200 kw Mod-0A wind power systems. Calculated and measured loads are compared for an experimental Mod-0 machine in operation. Predicted blade loads are also given for the higher power Mod-0A wind turbine now being assembled for operation as part of a municipal power plant. Two major structural modifications have been made to the Mod-0 wind turbine for the purpose of reducing blade loads. A stairway within the truss tower was removed to reduce the impulsive aerodynamic loading caused by the tower wake on the downwind rotor blades. Also, the torsional stiffness of the yaw drive mechanism connecting the turbine nacelle to the tower was doubled to reduce rotor-tower interaction loads. Measured reductions in load obtained by means of these two modifications equaled or exceeded predictions.

  18. National Wind Technology Center (Fact Sheet)

    SciTech Connect

    Not Available

    2011-12-01

    This overview fact sheet is one in a series of information fact sheets for the National Wind Technology Center (NWTC). Wind energy is one of the fastest growing electricity generation sources in the world. NREL's National Wind Technology Center (NWTC), the nation's premier wind energy technology research facility, fosters innovative wind energy technologies in land-based and offshore wind through its research and testing facilities and extends these capabilities to marine hydrokinetic water power. Research and testing conducted at the NWTC offers specialized facilities and personnel and provides technical support critical to the development of advanced wind energy systems. From the base of a system's tower to the tips of its blades, NREL researchers work side-by-side with wind industry partners to increase system reliability and reduce wind energy costs. The NWTC's centrally located research and test facilities at the foot of the Colorado Rockies experience diverse and robust wind patterns ideal for testing. The NWTC tests wind turbine components, complete wind energy systems and prototypes from 400 watts to multiple megawatts in power rating.

  19. Dynamics testing and modeling of NTS microwave tower

    SciTech Connect

    Weaver, H.J.; Burdick, R.B.; Woehrle, T.G.; McCallen, D.B.

    1987-01-15

    A dynamic evaluation of a typical NTS microwave tower was recently performed. This evaluation consisted of constructing a finite element model of the tower (using the GEMINI code). This model was then verified by performing a modal, or dynamic, test on the tower and then adjusting the finite element parameters so that the predicted resonant frequencies and mode shapes were in agreement with those actually measured. Based on the results of this dynamic evaluation it was found that the one of the modes of the guy wires coupled directly into the second mode of the microwave tower itself. In addition to this particular evaluation, this project has produced a ''calibrated'' finite element model of a typical NTS microwave tower that should be very useful in understanding the basic dynamics involved. Using this model, it is possible to predict the response motion and critical stresses in a tower when exposed to nuclear event ground motion.

  20. Performance improvement through participation in the Cooling Tower Institute

    SciTech Connect

    Stackhouse, D. [Ecodyne Cooling Tower Services, Somerville, NJ (United States)

    1995-02-01

    The Cooling Tower Institute (CTI) is an organization devoted to the design, operation, and maintenance of Cooling Towers. It consists of cooling tower users, equipment suppliers, and manufacturers working jointly to improve the state of the cooling tower {open_quotes}art{close_quotes}. This is primarily accomplished through the three primary technical committees: Engineering Standards, Performance and Technology, and Water Treatment. These committees develop, review, and update the CTI Codes and Standards which provide a common basis for the specification, performance testing, operation, and maintenance of Cooling Towers. The paper will discuss the operation of the CTI and how utility users can improve cooling tower performance and operation through the technical resources of the CTI as well as through active participation in CTI technical committees and seminars.

  1. Performance characteristics of an induced draft, counterflow, spray cooling tower

    E-print Network

    Jones, Charles Edward

    1951-01-01

    ~ 17 VXX. Interpretation of Data. . . . . . . . . . . . ~ ~ 87 3Dll i 0 Cz' spry s ~ ~ ~ ~ ~ ~ ~ e ~ ~ ~ ~ ~ ~ ~ ~ ~ 0 SS TA3LES I. Sym&ols and Daflnltions . ~ II, Nozzle Specifications. , ' ~ ~ ~ III, Tabu1sted Results. . . ~ . ~ ~ ~ ~ 8 e... ~ ~ 18 ~ ~ s Sl Experimental Tower. ~ nozzle Arrangements ~ ~. . . . . ~. . . ~ Page ~ ~ ~ 11 Tower characteristic, KaV/L, plotted against water rate, L, for three nozzle arrange- ment s ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ t ~ ~ ~ ~ ~ o ~ ~ ~ 16 Tower...

  2. 37. VIEW LOOKING SOUTH AT THE STATIC TEST TOWER. THIS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    37. VIEW LOOKING SOUTH AT THE STATIC TEST TOWER. THIS VIEW SHOWS TWO MAJOR CHANGES TO THE STATIC TEST TOWER: THE ADDITION OF THE NASA LOGO TO THE FACADE AND THE ADDITION OF THE UPPER STAGES TO THE JUPITER MISSILE IN THE WEST POSITION ON THE TOWER TO REPRESENT THE JUNO II CONFIGURATION. 1961, PHOTOGRAPHER UNKNOWN, FRED ORDWAY COLLECTION, U. S. SPACE AND ROCKET CENTER, HUNTSVILLE, AL. - Marshall Space Flight Center, Saturn Propulsion & Structural Test Facility, East Test Area, Huntsville, Madison County, AL

  3. 10. Photocopy of photograph of tower as constructed at Cape ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. Photocopy of photograph of tower as constructed at Cape Henlopen, Delaware, September 1926 (original photograph in National Archives and Records Service, Still Pictures Branch, RG 26, 26-LG-22-A), photographer G.W. Hitchens, September 10, 1926. "New Tower. Camera Station West 100 ft." - Mispillion Lighthouse, Beacon Tower, South bank of Mispillion River at it confluence with Delaware River at northeast end of County Road 203, 7 miles east of Milford, Milford, Sussex County, DE

  4. Harbater-Mumford Components and Towers of Moduli Spaces

    E-print Network

    Fried, Michael

    of projective systems of k-rational points on certain towers (Hn)n0 of algebraic varieties (given with maps Hn+1 is reached in the final section. To any system (Gn)n0 can be attached a tower (Hn)n0 of algebraic varieties. As an application, we construct, for every projective system (Gn)n0 of finite groups, a tower of corresponding

  5. Isoprene emissions and impacts in an ecological transition region inferred from tall tower measurements

    NASA Astrophysics Data System (ADS)

    Hu, L.; Millet, D. B.; Baasandorj, M.; Griffis, T. J.; Turner, P. A.; Helmig, D.; Curtis, A.; Jacques, H.

    2014-12-01

    We present a full year of continuous in-situ measurements of isoprene and its oxidation products methyl vinyl ketone and methacrolein (MVK+MACR) by PTR-MS from a 244 m tall tower in the US Upper Midwest (KCMP tall tower). The tower is located at an ecological transition between isoprene-emitting deciduous forest to the north and east, and predominantly non-isoprene-emitting agricultural landscapes to the west and south. Based on independent cartridge measurements and a source-tracer analysis, we estimate that anthropogenic interferences (or anthropogenic isoprene) contribute on average 20% of the observed PTR-MS m/z 69 signal during daytime in summer at the KCMP tall tower (and up to 80% at night). Interferences for MVK+MACR at m/z 71 are small (7%). After removing these interferences, the observed isoprene and MVK+MACR mixing ratios show pronounced seasonal cycles, reaching maxima of 2540 pptv (isoprene) and 2790 pptv (MVK+MACR) during summer. The KCMP tall tower is impacted both by nearby isoprene sources (with transport time within an isoprene lifetime) and more distant regional isoprene sources (with transport time exceeding an isoprene lifetime), as indicated by daytime enhancements of isoprene (but little MVK+MACR) under southwest winds, and enhancements of MVK+MACR (but little isoprene) under transport from other directions. We find that the GEOS-Chem chemical transport model driven with the MEGANv2.1 biogenic inventory can reproduce the observed isoprene mixing ratios to within model uncertainty once improved land cover and temperature estimates are implemented in the model. However, a model low bias in MVK+MACR of (25% - 66%) cannot be resolved, even across diverse model assumptions for chemistry, atmospheric mixing, and land cover. This suggests that, while isoprene emissions in the immediate vicinity of the KCMP tall tower are adequately captured, the model is still underestimating emissions across the broader region. Using the loss of HOx radicals relative to the loss of NOx radicals (LHOx/LNOx) in the model as an indicator, we find that this region experiences a strong seasonal shift between VOC-limited chemistry in the spring and fall and NOx-limited or transitional chemistry in the summer, and that this transition is driven by the temporal and spatial distribution of isoprene emissions.

  6. Numerical study of the performance of tornado-type wind energy systems

    SciTech Connect

    Ayad, S.S.

    1983-03-01

    The tornado-type wind energy system was proposed to utilize the pressure drop created by an intens vortex in a tower. The tower serves as a low pressure exhaust for the turbine. The author carried out a numerical solution of the tower flow, using the two-equation (kappa-epsilon) turbulence model, for the small size system tested by Yen, with a 0.127-m- (5-in.-) diam tower standing in a uniform wind flow. A comparison of the results with the measured pressure values verified the model. In the present work the same numerical model is used for a system with a tower that is completely embedded in an atmospheric boundary layer. The results show, for a tower in a boundary layer of the one-seventh power-law profile, about a 28% reduction of the values of power coefficient from those for a tower in a uniform stream. Calculations for the performance of a system with different tower heights and the same tower and turbine diameters show a sharp decrease of power for H/D less than or equal to 0.5. Analysis of the tangential velocity shows that the vortex should be maintained up to heights /ZETA//D less than or equal to 0.9 to avoid the decrease in power extraction. Numerical predictions are made for systems with tower diameters between 0.5 and 8 m (1.64 and 26.24 ft) using the same system geometry and approach flow conditions. The results show that the scale effect is negligible for systems of 4-m tower diameter or larger.

  7. 8. STATIC TEST TOWER NORTHWEST ELEVATION FROM THE POWER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. STATIC TEST TOWER - NORTHWEST ELEVATION FROM THE POWER PLANT TEST STAND. - Marshall Space Flight Center, Saturn Propulsion & Structural Test Facility, East Test Area, Huntsville, Madison County, AL

  8. 5. Elevated view across Stillwell Avenue showing control tower and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. Elevated view across Stillwell Avenue showing control tower and storefronts. Looking east by northeast. - Stillwell Avenue Station, Intersection of Stillwell & Surf Avenues, Brooklyn, Kings County, NY

  9. Interior detail of tower space; camera facing southwest. Mare ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior detail of tower space; camera facing southwest. - Mare Island Naval Shipyard, Defense Electronics Equipment Operating Center, I Street, terminus west of Cedar Avenue, Vallejo, Solano County, CA

  10. 44. ARTS AND INDUSTRIES BUILDING FROM SOUTH TOWER ROOF, LOOKING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    44. ARTS AND INDUSTRIES BUILDING FROM SOUTH TOWER ROOF, LOOKING SOUTHEAST - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  11. VERRAZANONARROWS BRIDGE, STATEN ISLAND TOWER, FORT WADSWORTH IN BACKGROUND LEFT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VERRAZANO-NARROWS BRIDGE, STATEN ISLAND TOWER, FORT WADSWORTH IN BACKGROUND LEFT - Verrazano-Narrows Bridge, Spanning Narrows between Fort Hamilton (Brooklyn) & Staten Island, Brooklyn, Kings County, NY

  12. The Damaging Effects of Earthquake Excitation on Concrete Cooling Towers

    SciTech Connect

    Abedi-Nik, Farhad [SADRA Institute of Higher Education, Tehran (Iran, Islamic Republic of); Sabouri-Ghomi, Saeid [K.N.T University of Technology, Tehran (Iran, Islamic Republic of)

    2008-07-08

    Reinforced concrete cooling towers of hyperbolic shell configuration find widespread application in utilities engaged in the production of electric power. In design of critical civil infrastructure of this type, it is imperative to consider all the possible loading conditions that the cooling tower may experience, an important loading condition in many countries is that of the earthquake excitation, whose influence on the integrity and stability of cooling towers is profound. Previous researches have shown that the columns supporting a cooling tower are sensitive to earthquake forces, as they are heavily loaded elements that do not possess high ductility, and understanding the behavior of columns under earthquake excitation is vital in structural design because they provide the load path for the self weight of the tower shell. This paper presents the results of a finite element investigation of a representative 'dry' cooling tower, using realistic horizontal and vertical acceleration data obtained from the recent and widely-reported Tabas, Naghan and Bam earthquakes in Iran. The results of both linear and nonlinear analyses are reported in the paper, the locations of plastic hinges within the supporting columns are identified and the ramifications of the plastic hinges on the stability of the cooling tower are assessed. It is concluded that for the (typical) cooling tower configuration analyzed, the columns that are instrumental in providing a load path are influenced greatly by earthquake loading, and for the earthquake data used in this study the representative cooling tower would be rendered unstable and would collapse under the earthquake forces considered.

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

    NASA Technical Reports Server (NTRS)

    Bolonkin, Alexander

    2003-01-01

    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.

  14. 9. DETAIL, NORTH FRONT, CENTRAL (TALLEST) TOWER, FROM THE NORTHWEST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. DETAIL, NORTH FRONT, CENTRAL (TALLEST) TOWER, FROM THE NORTHWEST - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  15. 39. CLOSER VIEW OF CAMPANILE FROM SOUTH TOWER ROOF, LOOKING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    39. CLOSER VIEW OF CAMPANILE FROM SOUTH TOWER ROOF, LOOKING NORTHEAST - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  16. Wind turbine/generator set having a stator cooling system located between stator frame and active coils

    DOEpatents

    Bevington, Christopher M.; Bywaters, Garrett L.; Coleman, Clint C.; Costin, Daniel P.; Danforth, William L.; Lynch, Jonathan A.; Rolland, Robert H.

    2012-11-13

    A wind turbine comprising an electrical generator that includes a rotor assembly. A wind rotor that includes a wind rotor hub is directly coupled to the rotor assembly via a simplified connection. The wind rotor and generator rotor assembly are rotatably mounted on a central spindle via a bearing assembly. The wind rotor hub includes an opening having a diameter larger than the outside diameter of the central spindle adjacent the bearing assembly so as to allow access to the bearing assembly from a cavity inside the wind rotor hub. The spindle is attached to a turret supported by a tower. Each of the spindle, turret and tower has an interior cavity that permits personnel to traverse therethrough to the cavity of the wind rotor hub. The wind turbine further includes a frictional braking system for slowing, stopping or keeping stopped the rotation of the wind rotor and rotor assembly.

  17. Dry cooling tower with water augmentation

    SciTech Connect

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

    1981-06-23

    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.

  18. 2D-4D Correspondence: Towers of Kinks versus Towers of Monopoles in N=2 Theories

    E-print Network

    Pavel A. Bolokhov; Mikhail Shifman; Alexei Yung

    2012-02-25

    We continue to study the BPS spectrum of the N=(2,2) CP(N-1) model with the Z_N-symmetric twisted mass terms. We focus on analysis of the "extra" towers found previously in [1], and compare them to the states that can be identified in the quasiclassical domain. Exact analysis of the strong-coupling states shows that not all of them survive when passing to the weak-coupling domain. Some of the states decay on the curves of the marginal stability (CMS). Thus, not all strong-coupling states can be analytically continued to weak coupling to match the observable bound states. At weak coupling, we confirm the existence of bound states of topologically-charged kinks and elementary quanta. Quantization of the U(1) kink modulus leads to formation of towers of such states. For the Z_N-symmetric twisted masses their number is by far less than N-1 as was conjectured previously. We investigate the quasiclassical limit and show that out of N possible towers only two survive in the spectrum for odd N, and a single tower for even N. In the case of CP^2 theory the related CMS are discussed in detail. In these points we overlap and completely agree with the results of Dorey and Petunin. We also comment on 2D-4D correspondence.

  19. Comparison of methane emissions from wetlands measured from aircraft and towers

    NASA Astrophysics Data System (ADS)

    Conley, S. A.; Faloona, I. C.; Drexler, J. Z.; Anderson, F. E.; Baldocchi, D. D.; Sturtevant, C. S.; Verfaillie, J. G.; Knox, S. H.

    2013-12-01

    The ability to estimate surface fluxes from light, fixed-wing aircraft is investigated during two flights over Twitchell Island, a heavily managed peatland dominated by irrigated crops approximately 6 km x 3 km in the Sacramento Delta. Flux towers provide a continuous measurement at a single point, while airborne fluxes provide a snapshot of a large area at a given time. The ability to integrate the two methods would provide a means to estimate a continuous regional flux from tower measurements. The single engine airplane (Mooney TLS), provided by Scientific Aviation, was flown around the island while concurrent flux measurements (latent & sensible heat, CO2, CH4) were being made from 4 m towers at two locations on the surface. The flux estimate made with the airplane uses horizontal mean wind measured in real-time from the airplane and the methane mixing ratio measured onboard with a Picarro f2301 analyzer. During the flights there was clear periodicity in all scalars measured coincident with the flight time required to circle the island (~6 minutes), indicating a connection between the surface and the observed signal in the airplane. For methane, higher mixing ratios were observed on the downwind side of the island. An internal boundary layer was observed, which we believe resulted from the Montezuma Hills wind farms upwind of Twitchell Island. Scalars were well-mixed throughout the depth of that internal boundary layer (~500m), which is shown to be consistent with a theoretical estimate of the internal boundary layer given the transition from the wind farm to the island vegetation. Surface emissions were estimated using a mass-balance approach where each of the terms in the scalar budget equation are estimated using a least squares minimization of the data while the airplane was within 10 km of the center of the island and the altitude was below 300 meters. Surface emission of methane during the first flight was estimated at 36 × 13 nmol m-2 s-1. During the same time period, the flux measured from the ground stations within the rice fields on the island was estimated at 44 nmol m-2 s-1. The close agreement suggests that this technique has great potential for integrating flux tower measurements over larger areas.

  20. Solar power tower development: Recent experiences

    SciTech Connect

    Tyner, C.; Kolb, G.; Prairie, M. [and others

    1996-12-01

    Recent experiences with the 10 MW{sub e} Solar Two and the 2.5 MW{sub t} TSA (Technology Program Solar Air Receiver) demonstration plants are reported. The heat transfer fluids used in these solar power towers are molten-nitrate salt and atmospheric air, respectively. Lessons learned and suggested technology improvements for next-generation plants are categorized according to subsystem. The next steps to be taken in the commercialization process for each these new power plant technologies is also presented.

  1. 75 FR 16732 - Action Affecting Export Privileges; Aqua-Loop Cooling Towers, Co.

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-02

    ...COMMERCE Bureau of Industry and Security Action...Aqua-Loop Cooling Towers, Co. In the Matter...Aqua-Loop Cooling Towers, Co. The Bureau of Industry and Security, U...Aqua-Loop Cooling Towers, Co....

  2. 47 CFR 73.1692 - Broadcast station construction near or installation on an AM broadcast tower.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...Broadcast station construction near or installation on an AM broadcast tower. 73.1692...Broadcast station construction near or installation on an AM broadcast tower. ...the AM station, as follows: (a) Installations on an AM nondirectional tower....

  3. A Remotely Piloted Aircraft (RPA) as a Measurement Tool for Wind-Energy Research

    NASA Astrophysics Data System (ADS)

    Wildmann, Norman; Bange, Jens

    2014-05-01

    In wind energy meteorology, RPA have the clear advantage compared to manned aircraft that they allow to fly very close to the ground and even in between individual wind turbines in a wind farm. Compared to meteorological towers and lidar systems, the advantage is the flexibility of the system, which makes it possible to measure at the desired site on short notice and not only in main wind direction. At the Center of Applied Geoscience at the University of Tübingen, the research RPA MASC (Multi-purpose Airborne Sensor Carrier) was developed. RPA of type MASC have a wingspan of about 3 m and a maximum take-off weight of 7.5 kg, including payload. The standard meteorological payload includes instruments for temperature, humidity, barometric pressure and wind measurement. It is possible to resolve turbulence fluctuations of wind and temperature up to 20 Hz. The autopilot ROCS (Research Onboard Computer System), which is developed at the Institute of Flight Mechanics and Control, University of Stuttgart, makes it possible to automatically follow predefined waypoints at constant altitude and airspeed. At a cruising speed of 24 m/s and a battery life of approx. one hour, a range of 80 km is feasible. The project 'Lidar Complex', funded by the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety, is part of the research network 'WindForS', based in Southern Germany. The goal of the project is to establish lidar technology for wind energy plant site evaluation in complex terrain. Additional goals are the comparison of different measurement techniques and the validation of wind-field models in not IEC 61400 conform terrain. It is planned to design a turbulent wind-field generator, fed by real measurement data, which can be used to analyse WEC behaviour. Two test sites were defined for the 'Lidar Complex' project, one in IEC-conform terrain about 15 km from the Baltic Sea, the other in the Swabian Alb, only 2 km downstream of a 100 m steep escarpment. At both sites, flight measurements were performed in 2013 with the RPA MASC. The data that was collected allows to investigate the influence of thermal stability of the atmosphere at the test site and turbulence intensity around individual wind energy converters (WECs). Several measurement flights were done to investigate the wake structure downstream a running WEC. Preliminary results will be presented as well as an outlook for future research with the instrument.

  4. An improved method for predicting seasonal and annual shadowing from cooling tower plumes

    NASA Astrophysics Data System (ADS)

    Carhart, R. A.; Policastro, A. J.; Dunn, W. E.

    An improved model developed at Argonne National Laboratory and the University of Illinois (ANL/UI) for predicting long-term shadowing due to cooling tower plumes is presented, and its assumption are compared with those used in previous models. The model is based on a method for the selection of representative categories of similar plumes developed by Dunn and Policastro (Dunn, 1980, Proc. IAHR Cooling Tower Workshop, San Francisco; Policastro et al., 1984, Report EPRI CS-3403-CCM). At a given site this method reduces the large number of meteorological data cases in a season or year to a much smaller number (?35) of representative cases, each of which will have a predicted plume substantially different from the others. Plume predictions for the reduced set of category representative cases are then made with the validated ANL/UI plume model. With category representative plume shape, wind speed, wind direction and sun angles available for each hour, full effects of sun angles for the latitude and longitude of the site to be studied are included. The ANL/UI model yields seasonal and annual isopleths of hours of additional shadowing or of percentage reduction in total and direct solar energy arriving at the ground on a horizontal surface. Results for two hypothetical sites with 500 MWe generating capacity are presented and contrasted, one at Syracuse, NY, and the other at Spokane, WA.

  5. Floating Offshore Wind Turbine Dynamics: Large-Angle Motions in Euler-Space

    E-print Network

    Sweetman, Bert

    Floating Offshore Wind Turbine Dynamics: Large-Angle Motions in Euler-Space Bert Sweetman Texas A&M University Lei Wang Texas A&M University Abstract: Floating structures have been proposed to support offshore-angle rigid body rotations of a floating wind turbine in the time domain. The tower and rotor-nacelle assembly

  6. Experimental validation of soil–structure interaction of offshore wind turbines

    Microsoft Academic Search

    S. Bhattacharya; S. Adhikari

    2011-01-01

    Estimating the natural frequencies of a wind turbine system consisting rotor, nacelle, tower, foundation and surrounding soil is one of the important design considerations. This paper experimentally investigates the behaviour of a model wind turbine supported on a particular type of foundation called a monopile. Monopile is a single large diameter (2.5–4m) long slender column inserted deep into the ground.

  7. Structural Dynamics of Offshore Wind Turbines subject to Extreme Wave Loading

    Microsoft Academic Search

    N ROGERS

    SYNOPSIS With interest increasing in the installation of wind turbines offshore of the UK and the preferred foundation method likely to be monopiles rather than gravity foundations, attention must be focussed on the structural analysis and design of the monopile and tower. While the effects of operational loads and wind loads are well understood, the consequences of wave loading need

  8. Development of Fully Coupled Aeroelastic and Hydrodynamic Models for Offshore Wind Turbines: Preprint

    Microsoft Academic Search

    J. M. Jonkman; P. D. Sclavounos

    2006-01-01

    Aeroelastic simulation tools are routinely used to design and analyze onshore wind turbines, in order to obtain cost effective machines that achieve favorable performance while maintaining structural integrity. These tools employ sophisticated models of wind-inflow; aerodynamic, gravitational, and inertial loading of the rotor, nacelle, and tower; elastic effects within and between components; and mechanical actuation and electrical responses of the

  9. Submarine tower escape decompression sickness risk estimation.

    PubMed

    Loveman, G A M; Seddon, E M; Thacker, J C; Stansfield, M R; Jurd, K M

    2014-01-01

    Actions to enhance survival in a distressed submarine (DISSUB) scenario may be guided in part by knowledge of the likely risk of decompression sickness (DCS) should the crew attempt tower escape. A mathematical model for DCS risk estimation has been calibrated against DCS outcome data from 3,738 exposures of either men or goats to raised pressure. Body mass was used to scale DCS risk. The calibration data included more than 1,000 actual or simulated submarine escape exposures and no exposures with substantial staged decompression. Cases of pulmonary barotrauma were removed from the calibration data. The calibrated model was used to estimate the likelihood of DCS occurrence following submarine escape from the United Kingdom Royal Navy tower escape system. Where internal DISSUB pressure remains at - 0.1 MPa, escape from DISSUB depths < 200 meters is estimated to have DCS risk < 6%. Saturation at raised DISSUB pressure markedly increases risk, with > 60% DCS risk predicted for a 200-meter escape from saturation at 0.21 MPa. Using the calibrated model to predict DCS for direct ascent from saturation gives similar risk estimates to other published models. PMID:25109085

  10. Detail of conning tower atop the submarine. Note the wire ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail of conning tower atop the submarine. Note the wire rope wrapped around the base of the tower, which may have been used in an attempt to pull the submarine offshore. - Sub Marine Explorer, Located along the beach of Isla San Telmo, Pearl Islands, Isla San Telmo, Former Panama Canal Zone, CZ

  11. The Sun Tower: An Inquiry Tool for a Dynamic Universe.

    ERIC Educational Resources Information Center

    Lester, Dan; Sissom, Betty; Camden, Linda

    2000-01-01

    Explains the use of a Sun Tower in different activities at elementary grade levels while addressing national and state science standards. Shows the movement and motion of the sun in the sky. Introduces an activity that includes the sun tower in which students observe the changes of shadows every half hour. (YDS)

  12. 7. Keeper's house, fog signal house and light tower, view ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Keeper's house, fog signal house and light tower, view north northeast, west and south sides of keeper's house and tower, southwest and southeast sides of fog signal house - West Quoddy Head Light Station, At eastern tip of West Quaddy Head, Lubec, Washington County, ME

  13. 16. TYPICAL VIEW OF PEARL HARBOR FROM SIGNAL TOWER OFFICE, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    16. TYPICAL VIEW OF PEARL HARBOR FROM SIGNAL TOWER OFFICE, LOOKING OUT AT MAIN CHANNEL ENTRANCE, WITH FORD ISLAND ON THE RIGHT. - U.S. Naval Base, Pearl Harbor, Signal Tower, Corner of Seventh Street & Avenue D east of Drydock No. 1, Pearl City, Honolulu County, HI

  14. 1. Light tower and fog signal house, view south southeast, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Light tower and fog signal house, view south southeast, east and north sides of tower, northeast and northwest sides of signal house - Libby Island Light Station, At southern tip of Libby Island at entrance to Machias Bay, Machiasport, Washington County, ME

  15. 2. Fog signal house and light tower, view west southwest, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Fog signal house and light tower, view west southwest, southeast and northeast sides of signal house, east and north sides of tower - Libby Island Light Station, At southern tip of Libby Island at entrance to Machias Bay, Machiasport, Washington County, ME

  16. 15. TYPICAL VIEW OF PEARL HARBOR FROM SIGNAL TOWER OFFICE, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. TYPICAL VIEW OF PEARL HARBOR FROM SIGNAL TOWER OFFICE, LOOKING OUT TOWARD ARIZONA MEMORIAL AND FORD ISLAND. - U.S. Naval Base, Pearl Harbor, Signal Tower, Corner of Seventh Street & Avenue D east of Drydock No. 1, Pearl City, Honolulu County, HI

  17. 25. Wood quench tower, chemical tank on right, hot gas ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    25. Wood quench tower, chemical tank on right, hot gas pipes between coke ovens and compressor building XX), coal conveyor to pulverizer building on right, water tank to left of quench tower. Looking north/northwest - Rouge Steel Company, 3001 Miller Road, Dearborn, Wayne County, MI

  18. 9. VIEW, LOOKING SOUTHEAST, ALONG CENTERLINE FROM SOUTH CANTILEVER TOWER. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. VIEW, LOOKING SOUTHEAST, ALONG CENTERLINE FROM SOUTH CANTILEVER TOWER. Note emergency bracing installed beneath collapsed tower, and crumpled vertical members at right and left. - Smith River Bridge, CA State Highway 199 Spanning Smith River, Crescent City, Del Norte County, CA

  19. PBF Cooling Tower. Camera facing southwest. Round piers will support ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    PBF Cooling Tower. Camera facing southwest. Round piers will support Tower's wood "fill" or "packing." Black-topped stack in far distance is at Idaho Chemical Processing Plant. Photographer: John Capek. Date: October 16, 1968. INEEL negative no. 68-4097 - Idaho National Engineering Laboratory, SPERT-I & Power Burst Facility Area, Scoville, Butte County, ID

  20. Design of cooling towers by the effectiveness-NTU method

    Microsoft Academic Search

    H. Jaber; R. L. Webb

    1989-01-01

    This paper develops the effectiveness-NTU, number of transfer units, design method for cooling towers. The definitions for effectiveness and NTU are totally consistent with the fundamental definitions used in heat exchanger design. Sample calculations are presented for counter and crossflow cooling towers. Using the proper definitions, a person competent in heat transfer design can easily use the same basic method

  1. PBF Cooling Tower contextual view. Camera facing southwest. West wing ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    PBF Cooling Tower contextual view. Camera facing southwest. West wing and north facade (rear) of Reactor Building (PER-620) is at left; Cooling Tower to right. Photographer: Kirsh. Date: November 2, 1970. INEEL negative no. 70-4913 - Idaho National Engineering Laboratory, SPERT-I & Power Burst Facility Area, Scoville, Butte County, ID

  2. Data Center Economizer Cooling with Tower Water; Demonstration of a

    E-print Network

    LBNL-6660E Data Center Economizer Cooling with Tower Water; Demonstration of a Dual Heat Exchanger exchanger was configured to use higher temperature water produced by a cooling tower alone. The other coil Rack Cooling Device H.C. Coles, S. Greenberg Environmental Energy Technologies Division November 2012

  3. Performance of cooling tower in south of Tunisia

    Microsoft Academic Search

    Lakdar Kairouani; Mohamed Hassairi; Zermani Tarek

    2004-01-01

    This paper presents a mathematical model for the numerical prediction of the performance of crossflow cooling towers. The mathematical model is based on the heat and mass transfer equations. The leading parameters are the Lewis number Le, the number of transfer units U, the percentage of water evaporation, the water losses and the tower efficiency. This model is used to

  4. Application of CFD to closed-wet cooling towers

    Microsoft Academic Search

    G Gan; S. B Riffat; L Shao; P Doherty

    2001-01-01

    Computational fluid dynamics (CFD) is applied to predicting the performance of closed-wet cooling towers (CWCTs) for chilled ceilings according to the cooling capacity and pressure loss. The prediction involves the two-phase flow of gas and water droplets. The predicted thermal performance is compared with experimental measurement for a large industrial CWCT and a small prototype cooling tower. CFD is then

  5. Aircraft Impact Analyses of the World Trade Center Towers

    Microsoft Academic Search

    D. Isobe; Z. Sasaki

    Although some official statements have been released by the Federal Emergency Management Agency (FEMA) and the National Institute of Standards and Technology (NIST), the 9\\/11 tragedy of the New York World Trade Center (WTC) towers still remains as an unresolved mystery since the progressive collapse sequence of the towers was unnaturally rapid. We sought the true cause of the collapse

  6. 32. VIEW LOOKING EAST AT THE STATIC TEST TOWER WHILE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    32. VIEW LOOKING EAST AT THE STATIC TEST TOWER WHILE A JUPITER MISSILE IS BEING POSITIONED ONTO THE TEST TOWER. DATE AND PHOTOGRAPHER UNKNOWN, MSFC PHOTO LAB. - Marshall Space Flight Center, Saturn Propulsion & Structural Test Facility, East Test Area, Huntsville, Madison County, AL

  7. 4. North elevation of Shell Interlocking Tower showing structure built ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. North elevation of Shell Interlocking Tower showing structure built into slope of railroad right-of-way. - New York, New Haven, & Hartford Railroad, Shell Interlocking Tower, New Haven Milepost 16, approximately 100 feel east of New Rochelle Junction, New Rochelle, Westchester County, NY

  8. 5. General oblique view of Shell Interlocking Tower to southwest, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. General oblique view of Shell Interlocking Tower to southwest, showing east and north facades. Relay station is on far left. - New York, New Haven, & Hartford Railroad, Shell Interlocking Tower, New Haven Milepost 16, approximately 100 feel east of New Rochelle Junction, New Rochelle, Westchester County, NY

  9. 11. General view of Shell Interlocking Tower, west and south ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. General view of Shell Interlocking Tower, west and south facades, view from railroad grade, looking northeast. - New York, New Haven, & Hartford Railroad, Shell Interlocking Tower, New Haven Milepost 16, approximately 100 feel east of New Rochelle Junction, New Rochelle, Westchester County, NY

  10. 13. View of Truss tower and pivot pier locking east. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. View of Truss tower and pivot pier locking east. When the draw is open, the two arms of the truss act as cantilevers supported by the truss tower. A counterweight in the shorter of the bridge keeps the span in proper balance. - Center Street Swing Bridge, Southwest of Public Square, Cleveland, Cuyahoga County, OH

  11. Guard tower structural design concept for perimeter security systems

    Microsoft Academic Search

    Risse

    1983-01-01

    Facilities that require outdoor perimeter sensor fields to furnish perimeter penetration alarms can often benefit by the inclusion of manned guard towers in the total security plan. Acquisition and maintenance costs of closed circuit television to provide adequate visual assessment may be too costly and perhaps tower personnel could perform other functions such as monitoring vehicles or personnel in the

  12. Photographic determination of drift characteristics. [A cooling tower research tool

    Microsoft Academic Search

    Hoffman

    1977-01-01

    Droplet photography is a well developed scientific tool that has already enjoyed much application in a wide spectrum of industries. It holds much potential as a cost effective accurate tool for cooling tower research and performance technology. Used in the laboratory, inside or outside the tower, it may be used to study drift characteristics and movement, drift eliminator performance, water

  13. Retrenching the Purse: Finite Sequence Numbers, and the Tower Pattern

    E-print Network

    Banach, Richard

    Retrenching the Purse: Finite Sequence Numbers, and the Tower Pattern Richard Banach 1 , Michael industrial scale application, and notably, was the first verification to achieve ITSEC level E6 certification developments of this kind: the Tower Pattern. 1 Introduction The Mondex Electronic Purse [18], produced

  14. $500 Charter Society $5,000 Tower Club

    E-print Network

    Danforth, Bryan Nicholas

    $2.500 $500 Charter Society Other $ $5,000 Tower Club $1,000 Quadrangle Club $250 Please share Museum of Art 002101 Hotel School 000603 Industrial and Labor Relations 000807 Lab of Ornithology 003664 CORNELL'S GIVING SOCIETIES: Presidents Circle $25,000 and up Dean's Circle $10,000-$24,999 Tower Club $5

  15. Power Tower Technology Roadmap and cost reduction plan

    Microsoft Academic Search

    Thomas R. Mancini; Jesse A. Gary; Gregory J. Kolb; Clifford Kuofei Ho

    2011-01-01

    Concentrating solar power (CSP) technologies continue to mature and are being deployed worldwide. Power towers will likely play an essential role in the future development of CSP due to their potential to provide dispatchable solar electricity at a low cost. This Power Tower Technology Roadmap has been developed by the U.S. Department of Energy (DOE) to describe the current technology,

  16. Retrenching the Purse: Finite Sequence Numbers, and the Tower Pattern

    E-print Network

    Banach, Richard

    Retrenching the Purse: Finite Sequence Numbers, and the Tower Pattern Richard Banach , Michael industrial scale application, and notably, was the first verification to achieve ITSEC level E6 certification developments of this kind: the Tower Pattern. 1 Introduction The Mondex Electronic Purse [18], produced

  17. 16. Detail, northeast facade, operator's bow window and tower; note ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    16. Detail, northeast facade, operator's bow window and tower; note condition of slates on tower skirt roof, missing section of gutter at left side of skirt roof, missing window panes; note also knee braces carried on masonry ancons; view to southwest, 90mm lens. - Southern Pacific Depot, 559 El Camino Real, San Carlos, San Mateo County, CA

  18. Transmission Line Tower Analysis and Design in Review

    Microsoft Academic Search

    R. A. Kravitz

    1982-01-01

    This paper presents a review of the state of the art and practice of transmission line tower design with specific attention to structure loading conditions, comparison of results using different tower analysis techniques and a comnentary on some criteria of the ASCE Manual 52 \\

  19. Within compound, from Guard Tower (Building 5762), looking southwest, Technical ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Within compound, from Guard Tower (Building 5762), looking southwest, Technical Equipment Building (Building 5760) to left, Microwave Tower (associated with Building 5769) and Civil Engineering Storage Building (Building 5766) to left - Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

  20. 10. View east from northwest (port) elevator tower to northeast ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. View east from northwest (port) elevator tower to northeast (starboard) elevator tower. Muzzle of deck torpedo tube projects from wall at lower right. - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI