Potentials of the Application of the Electrical Transmission Line Theory for Thermal Investigations on Cables

Abstract. In this contribution, similarities and differences between electrical and thermal effects on cables are investigated. In the electrical transmission line theory, a wide variety of methods is known to describe the voltage and current along cables. The potential for the adaption of some of those methods to thermal problems is discussed. Exemplarily, for an unshielded single cable, an analytical solution based on the Laplace transform and an approach based on cascaded equivalent circuits are compared with a numerical reference solution and measurement results.

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Analysis of transmission of vibrations in a porous vibroisolator on the basis of electrical transmission line theory

Journal of Sound and Vibration ◽

10.1016/s0022-460x(87)81336-6 ◽

1987 ◽

Vol 113 (1) ◽

pp. 9-16 ◽

Cited By ~ 1

Author(s):

R. Uklejewski

Keyword(s):

Transmission Line ◽

Electrical Transmission ◽

Transmission Line Theory ◽

Electrical Transmission Line ◽

Line Theory

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On Heaviside's contributions to transmission line theory: waves, diffusion and energy flux

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2017.0457 ◽

2018 ◽

Vol 376 (2134) ◽

pp. 20170457

Author(s):

Christopher Donaghy-Spargo

Keyword(s):

Transmission Line ◽

Transmission Lines ◽

Physical Nature ◽

Electromagnetic Theory ◽

Electrical Transmission ◽

Important Work ◽

Transmission Line Theory ◽

Energy Current ◽

Electrical Transmission Line ◽

Line Theory

This paper surveys some selected contributions of Oliver Heaviside FRS (1850–1925) to classical electromagnetic theory and electrical engineering science. In particular, the paper focuses on his contributions to the development of electrical transmission line theory and his deep insights into the ‘physical’ nature of the phenomena relating to nineteenth century telegraphic problems. Following a brief historical introduction to the life of Heaviside to put his achievements in context, we explore his contributions to the reformulation of Maxwell's equations and the understanding of electromagnetic wave propagation along the external region of transmission lines. This leads naturally to his researches regarding the electromagnetic diffusion process inside the line conductors and his subsequent realization that the circuital parameters, usually assumed constant, are not always so. Finally, taking both these internal and external viewpoints of the conductors, his important work regarding the flow of energy described by his ‘energy current’ concept is presented. This article is part of the theme issue ‘Celebrating 125 years of Oliver Heaviside's ‘Electromagnetic Theory’’.

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Resonant Behaviour of an Acoustical Transmission Line

Australian Journal of Physics ◽

10.1071/ph620513 ◽

1962 ◽

Vol 15 (4) ◽

pp. 513 ◽

Cited By ~ 2

Author(s):

HF Pollard

Keyword(s):

Transmission Line ◽

Normal Mode Analysis ◽

Mode Analysis ◽

Infinite Cylinder ◽

Electrical Transmission ◽

Transmission Line Theory ◽

Electrical Transmission Line ◽

Continuous Waves ◽

Line Theory ◽

Electromagnetic Waveguide

In the passage of elastic waves through a cylindrical rod, phenomena are exhibited that closely resemble those occurring in an electromagnetic waveguide. Following a discussion of the classical Pochhammer-Chree theory for an infinite cylinder, elastic wave propagation in a finite rod is considered under conditions ~hen the rod may be regarded as analogous to an electrical transmission line. In the case of a resonant system, normal mode analysis provides a simplified treatment and it is shown that the results are in agreement with transmission-line theory. A brief discussion is given regarding the identity of the pulse response of a system and its response to continuous waves.

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Three-Dimension Impedance Representation for Microwave Absorptive Ceramics

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.544.489 ◽

2013 ◽

Vol 544 ◽

pp. 489-492

Author(s):

Heng Liu ◽

Zhao Yang Zeng ◽

Yi Min Guo

Keyword(s):

Magnetic Property ◽

Transmission Line ◽

Surface Effect ◽

Three Dimensional ◽

Calculated Data ◽

Three Dimension ◽

Transmission Line Theory ◽

Measurement Results ◽

Line Theory ◽

Electro Magnetic

The application of three-dimension impedance representation for microwave absorptive ceramics was investigated. Based on transmission line theory, the electro-magnetic property of the ceramics was equivalent to impedance of a three-dimensional impedance network, and the surface effect was described by an added layer with certain impedance. Finally the usability of this representation was discussed by comparing the calculated data with the measurement results.

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Existence of High Frequency Electricity at Acupoints and Meridian Flow Observations via the Frequency Spectrum

Journal of Electromagnetic Engineering and Science ◽

10.26866/jees.2020.20.2.96 ◽

2020 ◽

Vol 20 (2) ◽

pp. 96-109

Author(s):

Taeho Son ◽

Moonhee Lee ◽

Choolhyeong Rhee ◽

Namsoo Kim

Keyword(s):

Frequency Spectrum ◽

Human Body ◽

High Frequency ◽

Current Flow ◽

Oriental Medicine ◽

Measured Spectrum ◽

Electrical Transmission ◽

Transmission Line Theory ◽

Electrical Transmission Line ◽

Line Theory

We revealed the existence of high frequency (HF) electricity flowing through the meridians known to oriental medicine by observing these signals at various acupoints on the human body. This was clearly and scientifically demonstrated by recording the frequency spectrum at these acupoints using a spectrum analyzer. The analysis of the measured spectrum found in 5 particular acupoints of each of the 12 meridians showed that a flow exists in these acupoints that could be measured with a spectrum frequency between 1 MHz and 80 MHz and an intensity of –70 to –60 dBm. Since the presence of these spectrums can be equated with the presence of electricity, we can emphatically conclude that high frequency electricity exists in humans and flows through the acupoints used in oriental medicine. The same characteristic frequency spectrums were found at all the acupoints along the same meridian and were shown to have the same type of HF current flow. In this way, we were able to confirm the existence of meridian flow in a scientific manner. In addition, it was found that as the distance from the organ increased, the intensities of the spectrum measured on that meridian decreased, which is exactly the behavior electrical transmission line theory would predict.

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