Download or read book Multiple station Measurements of Triggered Lightning Electric and Magnetic Fields written by David E. Crawford and published by . This book was released on 1998 with total page 566 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Lightning written by Vladimir A. Rakov and published by Cambridge University Press. This book was released on 2007-01-08 with total page 1485 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lightning: Physics and Effects is the first book that covers essentially all aspects of lightning, including lightning physics, lightning protection and the interaction of lightning with a variety of objects and systems as well as with the environment. It is written in a style that will be accessible to the technical non-expert and is addressed to anyone interested in lightning and its effects. This will include physicists, engineers working in the power, communications, computer and aviation industries, meteorologists, atmospheric chemists, foresters, ecologists, physicians working in the area of electrical trauma and architects. This comprehensive reference volume contains over 300 illustrations, 70 tables containing quantitative information and a bibliography of more than 6000 references.
Download or read book A Multiple station Experiment to Examine the Close Electromagnetic Environment of Natural and Triggered Lightning written by Jason E. Jerauld and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT (con't) : In addition, the induced current was measured in an 14 m grounded conducting structure. The system is automatically turned on and off by sensing the ambient electric field amplitude; and is triggered by simultaneous signals from the two optical sensors viewing the network from opposite orners. In addition to a complete description of the sensors and control system, representative data from both natural and triggered lightning, acquired in 2002, are presented.
Download or read book Rocket Triggered Lightning written by Li Cai and published by Springer Nature. This book was released on with total page 301 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Lightning Electromagnetics written by Robert Gardner and published by Routledge. This book was released on 2017-11-22 with total page 566 pages. Available in PDF, EPUB and Kindle. Book excerpt: A survey of theoretical and experimental research, this book covers all areas of lightning phenomenology. The four sections cover models of fundamental lightning processes, propagation of lightning-induced signals, measurement of lightning parameters, and lightning interaction with systems. The book provides an excellent review of the use of models to support remote sensing efforts. It includes data on high-frequency radiated fields for lightening and an overview of the data available in the frequency and time domains for lightning. The book also presents spectoral and temporal characteristics of lightning in the VHF-UHF frequency range and uses photographic and electromagnetic measurements to examine how lighting chooses a strike point.
Download or read book Lightning Principles Instruments and Applications written by Hans Dieter Betz and published by Springer Science & Business Media. This book was released on 2008-12-04 with total page 641 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lightning represents a natural phenomenon of substantial interest. Due to its complex nature, research continues in many countries and reveals amazing results. Lightning is actively observed because of its relevance to Earth climate and air composition in addition to the classical aspects of related human fatalities and damage to forests, buildings, power lines, aircraft, structures and electronic devices. In this volume, the most important contemporary questions on lightning are addressed and analyzed under many experimental and theoretical aspects. Lightning detection techniques using ground-based and space-borne methods are described, along with network engineering and statistical analysis. Contributions detail research on atmospheric electricity, cloud physics, lightning physics, modeling of electrical storms and middle atmospheric events. Special phenomena such as triggered lightning and sprite observations are examined. Lightning-induced nitrogen oxides and their effects on atmospheric chemistry and climate are discussed. Each topic is presented by international experts in the field. Topics include: * air chemistry * convective storms * infrasound from lightning * lightning and climate change * lightning and precipitation * lightning and radiation * lightning and supercells * lightning and thunderstorms * lightning detection * lightning from space * lighting protection * lightning return strokes * observations and interpretations * spatial distribution and frequency * triggered lightning * weather extremes
Download or read book Lightning Propagation and Ground Attachment Processes from Multiple station Electric Field and X ray Measurements written by Joseph Sean Howard and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT: The Multiple Station Experiment/Thunderstorm Energetic Radiation Array (MSE/TERA) network operating at the International Center for Lightning Research and Testing in Camp Blanding, FL has been used to examine the close RF electric and magnetic field and X-ray environment of cloud-to-ground lightning over a period from 2005 to 2007. Data were obtained for 18 natural and 9 rocket-triggered flashes that are thought to have terminated within or very near the network. The experimental system consisted of electric field sensors (bandwidth of 0.2 Hz to 3 MHz), magnetic field sensors (10 Hz to 3 MHz), dE/dt sensors (DC to 25 MHz), and Xray sensors (primary type had rise and fall times of 0.17 microseconds and 0.9 microseconds, respectively) spread around an area of about 0.5 km2, with the exact number of sensors varying from year to year. For rocket-triggered flashes, the channel-base-current was also measured (DC to 8 MHz). A subset of these measurements, consisting of eight dE/dt sensors and eight X-ray sensors, provided the network with time-of-arrival (TOA) location capabilities. This TOA network, which is the focal point of the present analyses, was used to investigate the spatial and temporal relationship between leader X-ray sources and electric-field-change sources as well as the role of post-leader processes in the production of X rays. The dE/dt portion of the TOA system was also 16 used to track and identify low-altitude processes occurring during the leader phase, attachment process, and return stroke with a higher degree of accuracy than previously possible with similar systems. A comparison of the collected waveforms, combined with these source locations, is used to obtain new insights into some of the more perplexing aspects of lightning, such as the step-formation process, leader propagation near ground, and the attachment process.
Download or read book Electromagnetic Computation Methods for Lightning Surge Protection Studies written by Yoshihiro Baba and published by John Wiley & Sons. This book was released on 2016-05-10 with total page 527 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presents current research into electromagnetic computation theories with particular emphasis on Finite-Difference Time-Domain Method This book is the first to consolidate current research and to examine the theories of electromagnetic computation methods in relation to lightning surge protection. The authors introduce and compare existing electromagnetic computation methods such as the method of moments (MOM), the partial element equivalent circuit (PEEC), the finite element method (FEM), the transmission-line modeling (TLM) method, and the finite-difference time-domain (FDTD) method. The application of FDTD method to lightning protection studies is a topic that has matured through many practical applications in the past decade, and the authors explain the derivation of Maxwell’s equations required by the FDTD, and modeling of various electrical components needed in computing lightning electromagnetic fields and surges with the FDTD method. The book describes the application of FDTD method to current and emerging problems of lightning surge protection of continuously more complex installations, particularly in critical infrastructures of energy and information, such as overhead power lines, air-insulated sub-stations, wind turbine generator towers and telecommunication towers. Both authors are internationally recognized experts in the area of lightning study and this is the first book to present current research in lightning surge protection Examines in detail why lightning surges occur and what can be done to protect against them Includes theories of electromagnetic computation methods and many examples of their application Accompanied by a sample printed program based on the finite-difference time-domain (FDTD) method written in C++ program
Download or read book Properties of Lightning Discharges from Multiple station Wideband Electric Field Measurements written by Stephen M. Davis and published by . This book was released on 1999 with total page 456 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Triggered lightning Properties Inferred from Measured Currents and Very Close Magnetic Fields written by Ashwin B. Jhavar and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT: Very close magnetic fields produced by rocket-triggered lightning measured in 1997, 1999, 2000, and 2001 at Camp Blanding, Florida, are examined. The leader and return stroke contributions to the total magnetic field are estimated and used to infer leader and return-stroke currents. The statistical characteristics of these inferred currents are examined. The return-stroke currents inferred from measured magnetic fields are compared with directly measured ones. Leader currents inferred from measured magnetic fields are compared with those estimated using dE/dt measurements. The statistics of the ratio of leader to return stroke currents are compiled. Current estimates from measured magnetic fields are in reasonable agreement with independent measurements and theoretical predictions found in the literature.
Download or read book The Effects of Lightning and High Altitude Electromagnetic Pulse on Power Distribution Lines written by and published by . This book was released on 1995 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt: We simultaneously recorded the voltages induced by lightning on both ends of an unenergized 448-meter long unenergized electric power line and the lightning vertical electric and horizontal magnetic fields at ground level near the line. The lightning data studied and presented here were due both to cloud lightning and to very close (about 20 m from the line) artificially initiated lightning. For cloud sources, a frequency-domain computer program called EMPLIN was used to calculate induced line voltages as a function of source elevation, angle of incidence, and wave polarization of the radiated cloud discharge pulses in order to compare with the measurements. For very-close lightning, the measured line voltages could be grouped into two categories, those in which multiple, similarly shaped, evenly spaced pulses were observed, which we call oscillatory, and those dominated by a principal pulse with subsidiary oscillations of much smaller amplitude, which we call impulsive. The amplitude of the induced voltage ranged from tens of kilovolts for oscillatory voltages to hundreds of kilovolts for impulsive voltages. A new technique is derived for the calculation of the electromagnetic fields from nearby lightning to ground above an imperfectly conducting ground. This technique was used in conjunction with an existing time domain coupling theory and lightning return stroke model to calculate voltages at either end of the line. The results show fair agreement with the measured oscillatory voltage waveforms if corona is ignored and improved results when corona effects are modeled. The modeling of the impulsive voltage, for which local flashover probably successful. In an attempt to understand better the sources of the line voltages for very close lightning, measurements of the horizontal and vertical electric fields 30 m from triggered lightning were obtained.
Download or read book Determining Distance to Lightning Strokes from a Single Station written by Lothar H. Ruhnke and published by . This book was released on 1971 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: A study has been made to use the differences between the decay of electric and magnetic fields near lightning strokes to determine the distance from a single station to the lightning. In our analysis a model of a return stroke is used to compute the waveform of electric and magnetic fields, between l km and 100 km distance, and the associated frequency spectrum. At distances small compared with the length of the return stroke channel, the electric field and also the magnetic field decrease inversely with distance from the stroke. From 3 km to 30 km the electric field, when observed at 1 kHz decreases approximately with the cube of the distance, while the magnetic field decreases with the square of the distance. For distances farther than 30 km, both signals decay inversely with distance. On an observation frequency of 1 kHz, it is possible to determine distances to return stroke channels between 3 km to 30 km by using the ratio of magnetic field to electric field. For this range, this ratio is independent of waveform and magnitude of the lightning signal. A prototype instrument was designed and tested during one thunderstorm season. The instrument uses loop antennas for sensing magnetic fields and horizontal wire antennas for sensing the electric field, and contains sharp filters, amplifiers, and peak voltage detectors. For the output, strip chart recorders are used. Data obtained with this instrument verify the predicted possibility of determining from a single station the distance to lightning strokes.
Download or read book Airborne and Ground Based Lightning Electric and Magnetic Fields and VHF Source Locations for a Two Stroke Ground Flash written by M. A. Uman and published by . This book was released on 1983 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: We have reduced and analyzed the data from a two-stroke lightning flash to ground which occurred in South Florida on July 16, 1981, within a network of four ground stations instrumented for VHF measurements, about 15 km from a ground station instrumented for wide-band electric field measurements, and within 10 km of a WC-130 aircraft operating at 5.2 km and instrumented for wide-band electric and magnetic field measurements. The four-station ground-based VHF measurements allow a reconstruction of the geometry of the flash, which was composed of two separate channels to ground. Electric field system bandwidth for the ground measurement was from 0.02 Hz to about 2 MHz; electric and magnetic field system bandwidths on the aircraft extended to 20 MHz. Ground-based and airborne measurements of fields are presented and shown to be consistent with one another. (Author).
Download or read book Analysis of Parameters of Rocket triggered Lightning Measured During the 1999 and 2000 Camp Blanding Experiment and Modeling of Electric and Magnetic Field Derivatives Using the Transmission Line Model written by Jens Schoene and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT (cont.): It is shown that, if the transmission line model is applicable at early times in the triggered lightning return stroke process, the electric and magnetic radiation field components become the largest components beyond distances of about 15 m but are not dominant for distances less than 100 m. The experimental data presented indicate that measured dE/dt, dB/dt, and dI/dt waveshapes are very similar for the first 150 ns or so after the initiation of the return stroke. It is shown that, based on transmission line modeling, the waveshapes of the dE/dt and dB/dt rising edges are relatively invariant for a return stroke speed v greater than or equal to 2*10 to the 8th power m/s and, further, that the total waveshapes are exactly the same for v = c. Additionally, it is shown that the dE/dt and dB/dt waveshapes do not depend much on channel inclination from the vertical, for inclinations less than 20 degrees and return stroke speeds higher than 10 to the 8th power m/s. The TLM models the electric field derivatives well when the observed inclined channel with its base at the strike rod base or a slightly shifted channel origin is assumed.
Download or read book Methodology and Technology for Power System Grounding written by Jinliang He and published by John Wiley & Sons. This book was released on 2012-11-28 with total page 618 pages. Available in PDF, EPUB and Kindle. Book excerpt: Grounding is the fundamental measures to ensure the safe operation of power systems, including power apparatus and control/monitoring systems, and guarantee the personal safety. Grounding technology is an interdiscipline involving electrical engineering, high voltage technology, electric safety, electromagnetics, numerical analysis, and geological exploration Methodology and Technology for Power System Grounding: Covers all topics related to power system grounding Presents fundaments and theories of grounding systems Well balances technology and methodology related to grounding system design Helps to understand the grounding analysis softwares Highlights the advanced research works in the field of grounding systems Comprehensively introduces numerical analysis methods Discovers impulse ionization phenomenon of soil around the grounding conductors Touches on lightning impulse characteristics of grounding devices for towers and buildings As a comprehensive treatment of the topic, Methodology and Technology for Power System Grounding is ideal for engineers and researchers in power system, lightning protection, and grounding. The book will also better equip postgraduates, senior undergraduate students in electrical engineering.
Download or read book The Lightning Discharge written by Martin A. Uman and published by Courier Corporation. This book was released on 2012-08-21 with total page 395 pages. Available in PDF, EPUB and Kindle. Book excerpt: Absorbing monograph by expert sets forth most of known properties of lightning: cloud and lightning charges, stepped leader, return stroke, dart leader, lightning on other planets, thunder, more. 144 illustrations.
Download or read book Measured Fields and Earth Potentials at 10 and 20 Meters from the Base of Triggered Lightning Channels written by and published by . This book was released on 1993 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
