Striations in Electromagnetic Stationary Waves

1953 ◽  
Vol 21 (5) ◽  
pp. 389-390 ◽  
Author(s):  
Grant O. Gale
Keyword(s):  
Stationary Waves

Numerical simulation of plane and spatial nonlinear stationary waves in a two-layer fluid of arbitrary depth

2008 ◽  
Vol 43 (1) ◽  
pp. 118-124
Author(s):  
A. A. Bocharov ◽  
G. A. Khabakhpashev ◽  
O. Yu. Tsvelodub
Keyword(s):  
Numerical Simulation ◽  
Stationary Waves

Ultrasonic Stationary Waves

Nature ◽  
1927 ◽  
Vol 120 (3022) ◽  
pp. 476-477 ◽  
Author(s):  
R. W. BOYLE
Keyword(s):  
Stationary Waves

Tropical influence on boreal summer mid-latitude stationary waves

2011 ◽  
Vol 37 (9-10) ◽  
pp. 1783-1798 ◽  
Author(s):  
Hervé Douville ◽  
S. Bielli ◽  
C. Cassou ◽  
M. Déqué ◽  
N. M. J. Hall ◽  
...  
Keyword(s):  
Boreal Summer ◽  
Stationary Waves

Interactions between stationary waves and ice sheets: linear versus nonlinear atmospheric response

2011 ◽  
Vol 38 (5-6) ◽  
pp. 1249-1262 ◽  
Author(s):  
Johan Liakka ◽  
Johan Nilsson ◽  
Marcus Löfverström
Keyword(s):  
Ice Sheets ◽  
Stationary Waves ◽  
Atmospheric Response

A discussion on advanced methods of energy conversion- Magnetohydrodynamic power generation - Wave growth in m .h.d. generators

1967 ◽  
Vol 261 (1123) ◽  
pp. 461-470 ◽  
Keyword(s):  
Thermodynamic Properties ◽  
Acoustic Waves ◽  
Subsonic Flow ◽  
Flow Direction ◽  
Noble Gas ◽  
Travelling Waves ◽  
Combustion Products ◽  
Stationary Waves ◽  
Ohmic Dissipation ◽  
Steady Current

It has been shown that in an m.h.d. generator, acoustic waves can grow due to the coupling of fluctuations in electrical conductivity, Hall parameter and thermodynamic properties of the gas, with the ohmic dissipation and electromagnetic body forces. A new analysis of this phenomenon is presented in which waves travelling at an arbitrary angle to the flow direction in a plane perpendicular to the magnetic field are considered. In contrast to McCune’s (1964) treatment the thermodynamic properties are not restricted to perfect gas laws; and the condition for spatially and temporally growing waves is examined using a general dispersion relation which includes both these types of wave. We consider in detail (i) stationary waves in supersonic flow, and (ii) travelling waves in the subsonic flow found in the G.E.G.B. 200 MW thermal input generator being built at Marchwood, and a possible power station m.h.d. generator. It is found that the waves in the 200 MW rig which burns kerosene in oxygen will be damped. But in an oil-air combustion products generator for Hall parameters of order 3 or greater, it is found that stationary waves which grow rapidly may occur at Mach numbers greater than about 1-7; and in subsonic flow waves propagating antiparallel to the steady current vector may be amplified, though the growth rate is not excessive. In noble gas m.h.d. generators these waves are more unstable than in the oil, air combustion products generator.

scholarly journals ON DIVERSITY OF CONFIGURATIONS GENERATED BY EXCITABLE CELLULAR AUTOMATA WITH DYNAMICAL EXCITATION INTERVALS

2012 ◽  
Vol 23 (12) ◽  
pp. 1250085 ◽  
Author(s):  
ANDREW ADAMATZKY
Keyword(s):  
Cellular Automata ◽  
Lower Boundary ◽  
Morphological Diversity ◽  
Excitable Media ◽  
Stationary Waves ◽  
Future Studies ◽  
Time Dynamics ◽  
Wide Range ◽  
Localized Excitations ◽  
Upper Boundary

Excitable cellular automata with dynamical excitation interval exhibit a wide range of space-time dynamics based on an interplay between propagating excitation patterns which modify excitability of the automaton cells. Such interactions leads to formation of standing domains of excitation, stationary waves and localized excitations. We analyzed morphological and generative diversities of the functions studied and characterized the functions with highest values of the diversities. Amongst other intriguing discoveries we found that upper boundary of excitation interval more significantly affects morphological diversity of configurations generated than lower boundary of the interval does and there is no match between functions which produce configurations of excitation with highest morphological diversity and configurations of interval boundaries with highest morphological diversity. Potential directions of future studies of excitable media with dynamically changing excitability may focus on relations of the automaton model with living excitable media, e.g. neural tissue and muscles, novel materials with memristive properties and networks of conductive polymers.

An experimental investigation of the nature and origin of microseisms at St. Louis, Missouri

1940 ◽  
Vol 30 (2) ◽  
pp. 139-178
Author(s):  
J. Emilio Ramirez
Keyword(s):  
Wave Length ◽  
Vertical Axis ◽  
The Other ◽  
Wave Form ◽  
Stationary Waves ◽  
Retrograde Motion ◽  
Time Signals ◽  
Group Form ◽  
Triangular Network ◽  
The Waves

Summary Over a period of six months, from July to December, 1938, an investigation on microseismic waves has been carried out in the Department of Geophysics of St. Louis University. Four electromagnetic seismographs, specially designed for recording microseisms, were installed in the city of St. Louis in the form of a triangular network. Two of these were E-W components, one at the St. Louis University Gymnasium and the other 6.4 km. due west at Washington University. The other two were arranged as N-S components, one at the St. Louis University Gymnasium and one 6.3 km. due south at Maryville College. The speed of the photographic paper was 60 mm/min., and time signals were recorded automatically and simultaneously on each paper from the same clock every minute and at shorter intervals from a special pendulum and “tickler” combination by means of telephone wires. The results have demonstrated beyond doubt that microseismic waves are traveling and not stationary waves. The same waves have been identified at each one of the stations of the network, and also at Florissant, 21.8 km. away from St. Louis University. The speed of microseismic waves at St. Louis was determined from several storms of microseisms and it was found to be 2.67±0.03 km/sec. The direction of microseisms was also established for most of the storms and it was found that about 80 per cent of incoming microseisms at St. Louis were from the northeast quadrant during the interval from July to December, 1938. No microseisms were recorded from the south, west, or southwest. The period of the waves varied between 3.5 and 7.5 sec. The average period was about 5.4 sec. The microseismic wave length was therefore of the order of 14¼ km. A study of the nature of microseismic waves from the three Galitzin-Wilip components of the Florissant station reveals in the waves many of the characteristics of the Rayleigh waves; that is, the particles in the passage of microseismic waves move in elliptical orbits of somewhat larger vertical axis and with retrograde motion. A comparison carried over a period of more than a year between microseisms and microbarometric oscillations recorded by specially designed microbarographs showed no direct relationship between the two phenomena in wave form, group form, period, or duration of storms. The source of microseisms is to be found not over the land, but rather out over the surface of the ocean. The amplitudes of microseisms depend only on the intensity and widespread character of barometric lows traveling over the ocean. Several correlations between the two phenomena seem to make this conclusion rather evident. Special emphasis is laid on the fact that all the determined directions of incoming microseisms at St. Louis point to a deep barometric low over the ocean. The period of microseisms seems to be a function of the distance between the station and the source of microseisms. The exact mechanism by which barometric lows over the ocean water result in the production of microseisms needs further investigation. Large microseisms have been produced without any indication of surf near the coasts, or with winds blowing from the land toward the ocean.

Sign in / Sign up

Export Citation Format

Share Document