Correlation properties of wind noise pressure on the ground surface

2021 ◽  
Vol 150 (4) ◽  
pp. A103-A103
Author(s):  
Richard Raspet ◽  
Craig J. Hickey ◽  
Md A. Samad
Keyword(s):  
Ground Surface ◽  
Wind Noise ◽  
Correlation Properties

Calculations of wind noise underneath a foam covering at the ground surface.

2009 ◽  
Vol 125 (4) ◽  
pp. 2630-2630
Author(s):  
Jiao Yu ◽  
Richard Raspet ◽  
Jeremy Webster ◽  
JohnPaul Abbott
Keyword(s):  
Ground Surface ◽  
Wind Noise

Wind noise measured at the ground surface

2011 ◽  
Vol 129 (2) ◽  
pp. 622-632 ◽  
Author(s):  
Jiao Yu ◽  
Richard Raspet ◽  
Jeremy Webster ◽  
JohnPaul Abbott
Keyword(s):  
Ground Surface ◽  
Wind Noise

Model Calculations of Wind Noise Measured in a Flat Surface Under Turbulent Flow

2008 ◽  
Author(s):  
Jiao Yu ◽  
Richard Raspet ◽  
Jeremy Webster ◽  
Kevin Dillion
Keyword(s):  
Velocity Profile ◽  
Wind Velocity ◽  
Pressure Fluctuations ◽  
Ground Surface ◽  
Theoretical Work ◽  
Wind Noise ◽  
Model Calculations ◽  
Noise Interference ◽  
Boundary Layer Turbulence ◽  
Average Wind

It has been proposed that microphones mounted flush on the ground surface should measure reduced wind noise levels since the microphone does not disturb the flow and the wind velocity at the ground is small. However, there are pressure fluctuations induced on the ground by the interaction of the turbulent fluctuations above the ground with the average wind velocity gradient. Model calculations of the pressure spectrum under different wind velocity profiles have been developed based on the theoretical work of Kraichnan.1 Kraichnan calculated the turbulence-shear contribution to pressure fluctuations under boundary layer turbulence with an exponentially varying flow velocity profile. The calculations presented here incorporate measured outdoor spectra of the turbulence and different models of the velocity profile to investigate pressure fluctuation measurements outdoors at the ground surface. The predicted power spectral densities of the pressure are compared to each other and to measurements. The ultimate purpose of this research is to develop means to minimize wind noise interference in acoustic measurements. [Research supported by the U.S. Army TACOM-ARDEC at Picatinny Arsenal, NJ.]

Aplikasi metode tahanan jenis dalam studi geologi karst Gua Seropan di Gunung Kidul, Yogyakarta

2017 ◽  
Vol 12 (2) ◽  
pp. 105-116
Author(s):  
Pulung A. Pranantya ◽  
Nurlia Sadikin
Keyword(s):  
Fresh Water ◽  
Ground Surface ◽  
Water Source ◽  
Raw Water ◽  
Limited Information ◽  
Resistivity Method ◽  
Central Java ◽  
Underground River ◽  
Initial Exploration

In terms of geology, most areas in south of the Gunungkidul District in Central Java consist of the Wonosari formation limestone. The land is generally very dry and source of raw water is also difficult to reach. Findings on the existence of underground river in caves, however, indicate the potential amount of water within the area, especially in the eastern part of the Gunungkidul District. Although limited information available, some fishermen have discovered that Seropan cave contains fresh water source. This cave is situated at 65 m below the cliff. Initial exploration, which done using a multichannel resistivity method, confirmed the availability of freshwater in the cave and underground river. The isopach of cave depth is found in ranges of 80 200 m below the ground surface. The water of Seropan cave can be utilized by implementing pipeline or by drilling at the suggested point based on the interpretation results, i.e. 110o2223.6388 EL 8o42.874 SL. [DY1][PP2][DY1]Perbaiki grammarIn terms of geology, most areas in south of Gunungkidul District in Central Java consist of the Wonosari formation limestone. The land is generally very dry and source of raw water is also difficult to reach. Findings on the exixtence of underground river in caves, however, indicate potential amount of water within the area especially in eastern part of Gunungkidul District. Although limited information available, some fishermans has discovered that Seropan cave contain fresh water source. This cave is situated at 65 m below the cliff. Initial exploration, which done using multichannel resistivity method, confirmed the availability of freshwater in the cave and underground river. The iso pach of cave depth is found in ranges of 80 200 m below the ground surface. The water of Seropan cave can be utilized by implementing pipeline or by drilling at the suggested point based on the interpretation results i.e. 110o2223.6388 EL 8o42.874 SL.[PP2]Sudah diperbaiki

Sign in / Sign up

Export Citation Format

Share Document