Wave propagation in one-dimensional inhomogeneous random media with an application to lower hybrid waves in fusion plasmas

Journal Article · Sun Jul 01 00:00:00 EDT 1990 · Physics of Fluids B; (USA)

DOI:https://doi.org/10.1063/1.859478· OSTI ID:6733328

Spigler, R ^[1]; Grossmann, W ^[2]

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1. Dipartimento di Metodi e Modelli Matematici per le Scienze Applicate, Universita di Padova, via Belzoni 7, 35131 Padova (Italy)
2. Science Applications International Corporation, 77 Bleecker Street, New York, NY (USA)

Wave propagation in a one-dimensional stratified medium, whose physical parameters are subject to random fluctuations, is considered. The complex-valued reflection coefficient obeys, as a function of the slab width {ital L}, a stochastic Riccati differential equation, associated with an initial-value problem. Using this fact, solving first the boundary-value problem satisfied by the field on (0,{ital L}) is avoided. The reflection coefficient can be computed numerically by a Monte-Carlo-type procedure by the generation of suitable sequences of random numbers aimed at constructing realizations of the stochastic processes that enter the refractive index. An application is made to the propagation of lower hybrid waves'' in thermonuclear (fusion) plasmas for realistic models of the deterministic density profile using available experimental data for the statistics of the random fluctuations. Several functional forms of the density profile are considered, and the relevant physical approximations are discussed. This work generalizes a previous analysis that did not include the inhomogeneous background density profile. Results show that the reflected power is a sensitive function of the form of the density profile.

• DOE Contract Number: AC02-76ER03077; FG02-86ER53223
• OSTI ID: 6733328
• Journal Information: Physics of Fluids B; (USA), Journal Name: Physics of Fluids B; (USA) Vol. 2:7; ISSN PFBPE; ISSN 0899-8221
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700108* -- Fusion Energy-- Plasma Research-- Wave Phenomena
CLOSED PLASMA DEVICES
DIFFERENTIAL EQUATIONS
EQUATIONS
FLUCTUATIONS
HEATING
HIGH-FREQUENCY HEATING
INHOMOGENEOUS PLASMA
LOWER HYBRID HEATING
MONTE CARLO METHOD
NUMERICAL SOLUTION
ONE-DIMENSIONAL CALCULATIONS
PLASMA
PLASMA DENSITY
PLASMA HEATING
RANDOMNESS
RICCATI EQUATION
SCATTERING
SLABS
STOCHASTIC PROCESSES
STRATIFICATION
THERMONUCLEAR DEVICES
TOKAMAK DEVICES
VARIATIONS
WAVE PROPAGATION