|
|
|
Title: Estimates of the Spatial Extent of High Frequencies from Spherical Blast Waves
Accession Number: 01054191
Record Type: Component
Availability: Institute of Noise Control Engineering Iowa State University, 210 Marston Hall Abstract: This paper presents an analysis that illustrates how the shock structure of a finite-amplitude waveform changes as it propagates. Because of the interaction of nonlinear effects, spherical spreading, and atmospheric absorption, the shock fronts thicken as the wave propagates. The larger shock widths result in longer rise times and less high frequency energy. Preliminary calculations show that high frequency energy above 10 kHz extends to a range of approximately 10-75 m. This range defines the area around a blast event where bats may be affected. However, dispersion has not been included in the calculations, and this can have a significant effect on shock rise times at certain frequencies8. In addition, factors such as ground impedance and atmospheric conditions are not included. Furthermore, the shock width is approximated by using a steepening sinusoid in this initial model. The waveforms created by actual explosions are more complicated. Additional computations to include these factors are planned for the future.
Monograph Accession #: 01054353
Language: English
Corporate Authors: Institute of Noise Control Engineering Iowa State University, 210 Marston Hall Transportation Research Board 500 Fifth Street, NW Authors: Loubeau, AlexandraSparrow, Victor WEditors: Burroughs, Courtney BMaling, George CPagination: pp 193-201
Publication Date: 2004
Conference:
Noise-Con 04. The 2004 National Conference on Noise Control Engineering
Location:
Baltimore Maryland, United States Media Type: CD-ROM
Features: Figures
(7)
; References
(18)
TRT Terms: Uncontrolled Terms: Subject Areas: Energy; Environment; Highways; I15: Environment
Files: TRIS, TRB
Created Date: Jul 16 2007 2:20PM
|
