Author: Allan D. PIERCE
Publisher:
ISBN:
Category :
Languages : en
Pages : 38
Book Description
This paper is concerned with the propagation of acoustic waves in temperature-and wind-stratified atmospheres in the geometrical acoustics' approximation. The basic theory of Blokhintzev is shown to hold for propagation in the atmosphere, even when gravitational forces and pressure gradients are included, if wave periods are sufficiently short. The 'ray-tracing' equations are derived from the eikonal approximation using Cauchy's method of characteristics, and the boundary conditions on these equations appropriate to a point source are discussed. Previous approximate methods of integrating the ray-tracing equations with the neglect of cross-winds are discussed, and a formulation due to Lee is corrected. A numerical method is introduced which alloys cross-winds to be taken into account. An extension of this method, to include earth curvature effects, is also included. (Author).
Geometrical Acoustics' Theory of Waves from a Point Source in a Temperature-and Wind-stratified Atmosphere
Author: Allan D. PIERCE
Publisher:
ISBN:
Category :
Languages : en
Pages : 38
Book Description
This paper is concerned with the propagation of acoustic waves in temperature-and wind-stratified atmospheres in the geometrical acoustics' approximation. The basic theory of Blokhintzev is shown to hold for propagation in the atmosphere, even when gravitational forces and pressure gradients are included, if wave periods are sufficiently short. The 'ray-tracing' equations are derived from the eikonal approximation using Cauchy's method of characteristics, and the boundary conditions on these equations appropriate to a point source are discussed. Previous approximate methods of integrating the ray-tracing equations with the neglect of cross-winds are discussed, and a formulation due to Lee is corrected. A numerical method is introduced which alloys cross-winds to be taken into account. An extension of this method, to include earth curvature effects, is also included. (Author).
Publisher:
ISBN:
Category :
Languages : en
Pages : 38
Book Description
This paper is concerned with the propagation of acoustic waves in temperature-and wind-stratified atmospheres in the geometrical acoustics' approximation. The basic theory of Blokhintzev is shown to hold for propagation in the atmosphere, even when gravitational forces and pressure gradients are included, if wave periods are sufficiently short. The 'ray-tracing' equations are derived from the eikonal approximation using Cauchy's method of characteristics, and the boundary conditions on these equations appropriate to a point source are discussed. Previous approximate methods of integrating the ray-tracing equations with the neglect of cross-winds are discussed, and a formulation due to Lee is corrected. A numerical method is introduced which alloys cross-winds to be taken into account. An extension of this method, to include earth curvature effects, is also included. (Author).
ESSA Technical Report IER-ITSA
Author:
Publisher:
ISBN:
Category : Meteorology
Languages : en
Pages : 988
Book Description
Publisher:
ISBN:
Category : Meteorology
Languages : en
Pages : 988
Book Description
Ionospheric Effects of Atmospheric Waves
Author: Thomas Martin Georges
Publisher:
ISBN:
Category : Ionosphere
Languages : en
Pages : 356
Book Description
Publisher:
ISBN:
Category : Ionosphere
Languages : en
Pages : 356
Book Description
Scientific and Technical Aerospace Reports
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 704
Book Description
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 704
Book Description
Technical Abstract Bulletin
Author:
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 760
Book Description
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 760
Book Description
Government-wide Index to Federal Research & Development Reports
Author:
Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 732
Book Description
Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 732
Book Description
Acoustic Echo Sounding as Related to Air Pollution in Urban Environments
Author: W. R. Simmons
Publisher:
ISBN:
Category : Air
Languages : en
Pages : 84
Book Description
The feasibility of operating an acoustic echo sounder in an urban or industrial environment, without serious degradation in performance and without contributing to noise pollution, is confirmed. Anechoic absorbers placed about the acoustic antenna are the key to improving the sounder performance. Optimum operating frequencies are between 1 and 2 kHz. The design and operation of the all solid state circuitry is described.
Publisher:
ISBN:
Category : Air
Languages : en
Pages : 84
Book Description
The feasibility of operating an acoustic echo sounder in an urban or industrial environment, without serious degradation in performance and without contributing to noise pollution, is confirmed. Anechoic absorbers placed about the acoustic antenna are the key to improving the sounder performance. Optimum operating frequencies are between 1 and 2 kHz. The design and operation of the all solid state circuitry is described.
Collected Reprints, 1972-73
Author: Wave Propagation Laboratory
Publisher:
ISBN:
Category : Atmosphere
Languages : en
Pages : 546
Book Description
Publisher:
ISBN:
Category : Atmosphere
Languages : en
Pages : 546
Book Description
ESSA Technical Reort IER.
Author: United States. Environmental Science Services Administration
Publisher:
ISBN:
Category :
Languages : en
Pages : 358
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 358
Book Description
Collected Reprints
Author:
Publisher:
ISBN:
Category : Atmosphere
Languages : en
Pages : 548
Book Description
Publisher:
ISBN:
Category : Atmosphere
Languages : en
Pages : 548
Book Description